tag:theconversation.com,2011:/au/topics/spring-8125/articlesSpring – The Conversation2024-02-29T17:37:28Ztag:theconversation.com,2011:article/2239302024-02-29T17:37:28Z2024-02-29T17:37:28ZPlants are flowering earlier than ever – here’s how they sense the seasons<p>Hedgerows in mid-February might have traditionally appeared white with snow; this year the white was the work of blackthorn blossoms – a harbinger of spring. Although a welcome sign after a wet and gloomy winter, the early flowering brings unease for experienced season watchers. Has this plant always flowered in mid-February, I wondered, or is something changing?</p>
<p>Fortunately, the science of recording and understanding seasonal events, phenology, has a long history in Britain. <a href="https://www.robertmarsham.co.uk/">Robert Marsham</a>, an 18th-century naturalist, kept records of the appearance of the flowers, birds and insects in his Norfolk village as far back as 1736. Marsham’s descendants continued the recording until 1958. The Woodland Trust maintains the tradition with <a href="https://naturescalendar.woodlandtrust.org.uk/">Nature’s Calendar</a>, a scheme in which members of the public are invited to record various seasonal events.</p>
<p><a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2021.2456">Detailed analysis</a> of almost half a million plant records by scientists in 2022 showed that when all species were considered together the average flowering time in the UK had advanced by a month over the last 40 years. There was variation between species. Hawthorn, the common hedgerow plant, is generally flowering 13 days earlier than it did in the early 1980s while the flowers of the horse chestnut tree appear ten days earlier.</p>
<p>The climate has warmed rapidly since the 1980s. By flowering earlier, plants recognise that winters are becoming shorter and milder. They sense the days getting warmer and alter their spring development in a manner akin to humans feeling warmth on their skin and so stepping out with fewer layers of clothing. The precise mechanisms for detecting these cues differ between plants and animals, but both are responding to the climate as it changes. </p>
<h2>Detecting light and heat without eyes and skin</h2>
<p>Plants detect the shortening days of autumn with a pigment called phytochrome that is particularly sensitive to wavelengths in the red region of the electromagnetic spectrum. The longer autumn nights alter the quality of this red light. While this subtle shift escapes humans (our eyes are not sensitive to this part of the spectrum) a plant can detect this transition and start to change.</p>
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<img alt="A bench next to a woodland at sunset." src="https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578640/original/file-20240228-18-qoad8t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Plants detect subtle changes in red light and instigate dormancy as autumn descends.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/romantic-autumn-mood-sunset-lake-ammersee-690569119">Art180/Shutterstock</a></span>
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<p>Just as the autumn can engineer a drop in the level of the hormone serotonin in our blood, a plant that has sensed winter’s approach will increase the production of a hormone called abscisic acid. This has multiple effects. In deciduous trees, twigs stop growing and develop tough winter buds capable of surviving frost and snow and leaves fall off.</p>
<p>Growth in spring is determined by similar triggers of light length and temperature, but temperature typically has the more significant role. If plants only paid attention to light, they’d run the risk of starting growth when fatal frosts are still a threat or of missing good growing time in mild early spring days. Temperature detection determines when spring flowers appear. This is why global heating is evident in the earlier appearance of these flowers.</p>
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<p><em>Do the seasons feel increasingly weird to you? You’re not alone. Climate change is distorting nature’s calendar, causing plants to flower early and animals to emerge at the wrong time.</em></p>
<p><em>This article is part of a series, <a href="https://theconversation.com/uk/topics/wild-seasons-152175?utm_source=InArticleTop&utm_medium=TCUK&utm_campaign=WS">Wild Seasons</a>, on how the seasons are changing – and what they may eventually look like.</em></p>
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<p>It isn’t fully understood how plants detect temperature. Some of it may be due to a growth-stalling hormone in its cells breaking down when the air falls below a certain temperature, which in turn allows a growth hormone to increase. </p>
<p>While humans have nerves in their skin to detect temperature, plants probably rely on pigments, though the mechanism isn’t fully understood. Heat is part of the same electromagnetic spectrum that phytochrome is sensitive to, so possibly this pigment is involved. Whatever mechanisms are responsible for initiating growth, temperature also determines how fast plants grow.</p>
<h2>Flowers and pollinators out of sync</h2>
<p>Insect pollinators like bees must synchronise their life cycles so that they are on the wing when the blossoms on which they feed emerge. The timing of their emergence from winter is also determined by the effects of temperature and day length and mediated by hormones. </p>
<p>Evolution working on many generations of pollinators has generated a tight link between the emergence of flowers and that of their pollinators. If the appearance of flowers and pollinators isn’t synchronised, the insects have no nectar and the plants aren’t fertilised. </p>
<p>A similar link exists between the emergence of leaves and the insect herbivores that graze on them. The rapidity of climate change and slight differences in how the two groups respond risk breaking this synchrony with serious consequences for both sides.</p>
<p><a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2021.2142">A large study</a> by German scientists looking at when flowers and their pollinators emerged between 1980 and 2020 found a complex picture. Both responded to climate change with earlier flowering and appearances, but the plants had made a greater shift. </p>
<p>There was variation between insect groups, bees and butterflies had shifted in synchrony with the plants, but this wasn’t observed in hoverflies. There was also variation between species of these insects.</p>
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<img alt="A white butterfly on a purple flower." src="https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=409&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=409&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=409&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578642/original/file-20240228-30-erxph1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Plants and insects co-evolved to emerge at roughly the same time in Spring.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/blackveined-white-butterfly-aporia-crataegi-perfect-79443766">Marek Mierzejewski/Shutterstock</a></span>
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<p>Even when plants and their dependent insects change timings in synchrony, the next stage of the food chain may not be so flexible. Oak leaves are fed upon by the oak moth caterpillar. This, in turn, is the primary food of the chicks of birds such as blue tits and pied flycatchers <a href="https://www.nature.com/articles/s41559-018-0543-1">link text</a>. Chicks have hatched at roughly the same time, while oak leaves and caterpillars have appeared earlier and so far remain in synchrony. But for how long?</p>
<p>Blackthorn blossoms remain a welcome relief from winter and a sign that spring is on its way. But they are also a sign of climate change: an unfolding experiment on the timing and synchrony of plants and animals – and the intricate food chains that they are part of.</p><img src="https://counter.theconversation.com/content/223930/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Ashton does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Rising air temperatures mean shorter winters and earlier springs.Paul Ashton, Professor of Botany, Edge Hill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2245812024-02-28T22:31:32Z2024-02-28T22:31:32ZHow climate change is messing up the ocean’s biological clock, with unknown long-term consequences<figure><img src="https://images.theconversation.com/files/578761/original/file-20240228-30-1ljbi.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3199%2C2400&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A satellite image of a phytoplankton bloom off the coast of St. John's, N.L.</span> <span class="attribution"><span class="source">(NASA, MODIS Rapid Response)</span></span></figcaption></figure><p>Every year in the <a href="https://www.ncesc.com/geographic-faq/what-is-the-middle-and-lower-latitude/">mid-latitudes</a> of the planet, a peculiar phenomenon known as the <a href="https://earthobservatory.nasa.gov/features/Phytoplankton">phytoplankton</a> <a href="https://doi.org/10.1111/gcb.13858">spring bloom</a> occurs. Visible from space, spectacular large and ephemeral filament-like shades of green and blue are <a href="https://doi.org/10.1029/2012GL052756">shaped by the ocean currents</a>.</p>
<p>The phytoplankton blooms are comprised of a myriad of microscopic algae cells growing and accumulating at the ocean’s surface as a result of the onset of longer days and fewer storms — often associated with the move into spring.</p>
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Read more:
<a href="https://theconversation.com/how-climate-change-induced-stress-is-altering-fish-hormones-with-huge-repercussions-for-reproduction-213140">How climate change-induced stress is altering fish hormones — with huge repercussions for reproduction</a>
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<p>The timing of the phytoplankton spring bloom is, however, <a href="https://doi.org/10.1111/gcb.13886">likely to be altered</a> in response to climate change. Changes which will affect — for good or ill — the many species that are <a href="https://doi.org/10.1146/annurev-marine-052913-021325">ecologically adapted</a> to benefit from the enhanced feeding opportunity that blooms represent at crucial stages of their development.</p>
<h2>Fine-tuned ecological adaptation</h2>
<p>Phytoplankton blooms are, in some aspects, <a href="https://doi.org/10.1111/gcb.14650">metronomes of the annual oceanic cycles</a> around which many species’ biological clocks are synced to.</p>
<p>One example is the zooplankton <a href="https://zooplankton.nl/en/diversity/copepods/"><em>Calanus finmarchicus</em></a>, a class of micro-organism only capable of swimming up and down through the water column. <em>Calanus finmarchicus</em> usually spend the winter in <a href="https://doi.org/10.1146/annurev-marine-010816-060505">diapause</a> — the marine version of hibernation — surviving on their accumulated energy reserves in the deep ocean. At the moment they deem appropriate in the spring, they raise from the abyss to graze on the bloom and reproduce.</p>
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<a href="https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image of a Calanoid Copepod." src="https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578760/original/file-20240228-7861-gu0ol7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">An image of an individual in the Calanoid Copepod group. The Calanoid Copepod is one of three groups of animals within the general category of Copepods, encompassing around 10,000 species. The Calanus finmarchicus is a member of the Calanoid Copepods group.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Fish and shellfish, too, are adapted to this natural metronome. </p>
<p>For some species, such as shrimp, females strategically lay their eggs in the water in advance of these blooms so their young will have ample food supplies from the moment they hatch</p>
<p>As incredible as it seems, some species can “calculate” the egg incubation period so that eggs hatch on average <a href="https://doi.org/10.1126/science.1173951">within a week</a> of the expected spring bloom.</p>
<h2>A question of timing</h2>
<p>This, unfortunately, is where climate change is entering into the equation. What was normal in the past may well be changing more rapidly than marine species can adapt. </p>
<p>Zooplankton and fish larvae constitutes the bulk of what ocean scientists call secondary production. Secondary production is a <a href="https://doi.org/10.1139/f2012-050">key trophic level</a> that links primary production (the phytoplankton using the sun’s light to produce biomass) and higher trophic levels, such as fish and marine mammals.</p>
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<a href="https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite image of a phytoplankton bloom." src="https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=607&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=607&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=607&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=762&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=762&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578762/original/file-20240228-30-q7p1qc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=762&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A massive phytoplankton bloom seen off the Northern coast of Norway. Phytoplankton blooms can reach thousands of square kilometres in size.</span>
<span class="attribution"><span class="source">(ESA, Envisat Pillars)</span></span>
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<p>This grand relationship is known as a <a href="https://doi.org/10.1016/j.tree.2016.08.010">trophic cascade</a>, as the zooplankton are eaten by the small fish and the small fish, in turn, are eaten by the bigger fish. A whole ecosystem beating on a clock largely determined by the timing of the phytoplankton spring bloom, hopefully in sync with the biological clocks of other species.</p>
<p>Any change to the timing of the spring bloom, for example as a result of climate change, can potentially have catastrophic consequences for the survival of zooplankton populations alongside the fishes and ecosystems which rely upon this abundant foodstuff. </p>
<p>This theory is known as the <a href="https://doi.org/10.1016/S0065-2881(08)60202-3">match/mismatch hypothesis</a> and postulates that the consumer’s energy demand should “match” the peak resource availability</p>
<h2>A new understanding</h2>
<p>On the Newfoundland and Labrador shelf in the Northwest Atlantic, the spring bloom <a href="https://doi.org/10.1002/jgrg.20102">generally starts</a> earlier in the south (mid-March on the Grand Banks of Newfoundland) and later in the north (late April on the southern Labrador shelf).</p>
<p>The south-to-north progression of the bloom was long believed to be related to the <a href="https://doi.org/10.1093/plankt/fbm035">annual retreat of sea ice</a> in the region.
But with the duration and spatial extent of the sea ice season being <a href="https://publications.gc.ca/collections/collection_2023/mpo-dfo/Fs97-6-3544-eng.pdf">dramatically reduced</a> in Atlantic Canada over the recent years, the relationship between sea ice and the timing of the bloom weakened.</p>
<p>I — alongside a team of researchers from across Canada — <a href="https://doi.org/10.1002/lol2.10347">proposed a new theory</a> to explain the initiation of the spring bloom on the Newfoundland and Labrador shelf. </p>
<p>Our theory points to transition from winter to spring as being key to trigger the bloom. In winter, cold and stormy conditions keep the ocean well mixed. However, the arrival of spring brings calmer winds and warming temperatures — coupled with increased freshwater flows. These conditions cause the ocean to reorganize into layers of different density — a phenomenon called <a href="https://doi.org/10.1093/plankt/fbv021">re-stratification</a>.</p>
<p>Re-stratification effectively prevents the phytoplankton cells of the upper layers from becoming easily mixed in the maelstrom of oceanic forces.
Their accumulation at the ocean’s surface creates the bloom.</p>
<p>This new mechanism successfully predicts the timing of the phytoplankton spring bloom over more than two decades. It also allows us to better understand the impacts that climate change is having upon our oceans.</p>
<h2>Ecological significance</h2>
<p>Located at the confluence of sub-arctic and sub-tropical ocean currents, the Newfoundland and Labrador shelf is naturally subjected to <a href="https://doi.org/10.5194/essd-13-1807-2021">large fluctuations</a> of its climate, with impacts on the timing of the bloom.</p>
<p>Our study has shown that a warmer climate is associated with earlier re-stratification, earlier phytoplankton blooms and a higher abundance of key zooplankton species such as <em>Calanus finmarchicus</em> in the region.</p>
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Read more:
<a href="https://theconversation.com/climate-change-is-further-reducing-fish-stocks-with-worrisome-implications-for-global-food-supplies-217428">Climate change is further reducing fish stocks with worrisome implications for global food supplies</a>
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<p>This discovery opens the door to a better understanding of bloom dynamics and the oceanic conditions driving the health of the ecosystem.</p>
<p>The good news for a cold region such as the Newfoundland and Labrador shelf is that a warmer climate with milder springs, like the ones we have <a href="https://www.dfo-mpo.gc.ca/csas-sccs/Publications/ResDocs-DocRech/2022/2022_040-eng.html">seen in recent years</a>, will lead to more and more abundant levels of phytoplankton — with clear benefits to ecosystem productivity. </p>
<p>However, for how long these changes will remain positive in a changing climate we cannot say.</p><img src="https://counter.theconversation.com/content/224581/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Frédéric Cyr does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Recent research sheds light on the ocean’s annual ‘biological clock’ and highlights the key dynamics that make it susceptible to climate change.Frédéric Cyr, Adjunct Professor, Physical Oceanography, Memorial University of NewfoundlandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2135902023-10-25T10:49:23Z2023-10-25T10:49:23ZHow climate change is affecting the seasons<figure><img src="https://images.theconversation.com/files/555566/original/file-20231024-29-a074ma.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C3686%2C3637&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beautiful-autumnal-scenery-tree-tunnel-regents-747085630">I Wei Huang/Shutterstock</a></span></figcaption></figure><p>Autumn has finally arrived in the UK following an <a href="https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/weather/learn-about/uk-past-events/interesting/2023/2023_05_september_heatwave.pdf">unusually sunny September</a>. The days are growing shorter, the temperature cooler, and the leaves are changing colour. </p>
<p>The delayed onset of autumn in 2023 is not a one off. It’s actually part of a broader trend in which the shift from summer to winter is happening later in the year. My <a href="https://www.researchgate.net/publication/259844410_C_Jeganathan_J_Dash_and_PM_Atkinson_2014_Remotely_sensed_trends_in_the_phenology_of_northern_high_latitude_terrestrial_vegetation_controlling_for_land_cover_change_and_vegetation_type_Remote_Sensing_o">own research</a> that I’ve carried out over the past 13 years points towards climate change as the likely culprit.</p>
<p>One of the most noticeable effects of climate change is the changing patterns of vegetation seasonality around us. This includes the timing of important biological events such as bud burst, the appearance of the first leaves, flowering and leaf fall.</p>
<p>In general, the appearance of the first leaf marks the arrival of spring, while leaf fall signals the beginning of autumn. The timing of these events is changing, particularly in the northern hemisphere, where spring appears to be starting earlier and autumn’s onset is being delayed.</p>
<p>Traditionally, monitoring vegetation seasonality involved meticulously documenting these seasonal events year after year. The earliest records of spring events in the UK date back to 1736, when naturalist <a href="https://www.britannica.com/science/phenology#:%7E:text=Robert%20Marsham%E2%80%99s%20observations">Robert Marsham</a> began recording the timing of spring events in Norwich, England. </p>
<p>Today, satellite data has become an essential tool for tracking changes in vegetation seasonality. This data can be used to estimate vegetation vigour (an indicator of vegetation’s condition, strength and lushness). Changes can then be used to identify the start and end of each growing season.</p>
<h2>Longer growing seasons</h2>
<p>Climate researchers now have nearly five decades of satellite observations at their disposal. Analysis of this data reveals that spring has advanced by approximately 15 days, while autumn has been delayed by a similar amount. The overall outcome has been the extension of the growing season by an entire month over the past three decades.</p>
<p>The shift in the timing of the seasons is particularly pronounced at higher latitudes. Vegetation situated more than 55° north of the equator, such as in the larch forests of northern Russia, has shown a trend towards an extended growing season, increasing by up to one day per year.</p>
<p>A longer growing season is not necessarily a bad thing. It means a longer period of photosynthesis, which theoretically could boost <a href="https://www.britannica.com/technology/carbon-sequestration">net carbon uptake</a> – although there is <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2022JG006900">no concrete evidence</a> for this yet.</p>
<p>But an earlier onset of the growing season exposes plants to the risk of damage from spring frosts and an increased vulnerability to summer drought. <a href="https://www.science.org/doi/10.1126/sciadv.aba2724">Research</a> has found that an early spring in central and northern Europe in 2018 promoted increased vegetation growth. This, in turn, contributed to soil losing its moisture quickly, amplifying summer drought conditions.</p>
<figure class="align-center ">
<img alt="A view of a coniferous forest with a sea bay and hills in the distance." src="https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/555571/original/file-20231024-29-9r2jaf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The shift in the timing of the seasons is particularly pronounced at higher latitudes.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beautiful-autumn-landscape-view-larch-trees-2207472441">Andrei Stepanov/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Role of climate change</h2>
<p>Temperature is <a href="https://www.nature.com/articles/nclimate3277">one of the primary factors</a> influencing vegetation growth at high northerly latitudes. So, an earlier onset of spring and a later arrival of autumn are probably driven by the rising global mean temperature. Since 1981, the global mean temperature has increased by <a href="https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202213">0.18°C per decade</a>.</p>
<p>Nonetheless, the influence of temperature on the duration of the growing season may change depending on the type of vegetation. In ecosystems primarily dominated by forests, a warmer climate <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2022JG006900">can lead to</a> more photosynthesis and increased vegetation productivity. </p>
<p>On the other hand, in a warmer climate, more water evaporates from the Earth’s surface, drying out the soil. This could adversely affect the growth of plants with shallow roots, such as grasses and herbaceous plants.</p>
<p>Another consequence of climate change is the increased frequency of droughts during the peak of the growing season. Drought conditions result in severe water stress for plants, leading to the premature shedding of leaves or a change in their colour, a phenomenon often referred to as a “false autumn”. </p>
<p>The UK <a href="https://www.bbc.co.uk/news/science-environment-62582186">experienced such conditions</a> in August 2022, when there was an early leaf fall and the browning of leaves, as the country grappled with an <a href="https://www.reuters.com/world/uk/extreme-weather-warning-force-britain-new-heatwave-hits-2022-08-11/">extreme heatwave</a>.</p>
<p>A longer and drier growing season can also increase the risk of forest fires. A <a href="https://www.science.org/doi/10.1126/science.1128834">US study</a> from 2006 revealed a significant surge in wildfire activity within the forests of the northern Rockies from the mid-1980s. This change was closely linked to increased spring and summer temperatures and an earlier spring snowmelt.</p>
<figure class="align-center ">
<img alt="Yellow and orange maple leaves on the ground in the sunlight." src="https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/555574/original/file-20231024-21-pk0kuk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Trees sometimes shed their leaves early when under stress.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/yellow-orange-maple-leaves-forest-on-1988839673">MVolodymyr/Shutterstock</a></span>
</figcaption>
</figure>
<p>Climate change is having a clear impact on vegetation growth and seasonality. But the extent and severity of its impact varies depending on the type of plant and where it grows.</p>
<p>The availability of satellite data spanning the past 50 years is a valuable resource for capturing changes in the duration of the vegetation growing season. This data is helping scientists quantify the scale and consequences of these changes, providing insights into how plants are responding to our warming climate.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 20,000+ readers who’ve subscribed so far.</a></em></p>
<hr><img src="https://counter.theconversation.com/content/213590/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jadu Dash does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Autumn is arriving later in the year – climate change is probably to blame.Jadu Dash, Professor of Remote Sensing in Geography and Environmental Science, University of SouthamptonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2136432023-10-01T19:16:32Z2023-10-01T19:16:32ZOur mood usually lifts in spring. But after early heatwaves and bushfires, this year may be different<p>When we think of spring, we might imagine rebirth and renewal that comes with the warmer weather and longer days. It’s usually a time to celebrate, flock to <a href="https://floriadeaustralia.com">spring flower festivals</a> and spend more time in nature.</p>
<p>Spending time in nature or doing things outside, such as <a href="https://journals.sagepub.com/doi/abs/10.1177/1757913915589845">exercising</a> or <a href="https://www.sciencedirect.com/science/article/pii/S2352827321002093">gardening</a>, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0272494419301185">lifts our mood</a>.</p>
<p>But this year, with an <a href="https://twitter.com/Reuters/status/1704325785627050136">early start</a> to the bushfire season, and the <a href="https://theconversation.com/worried-about-heat-and-fire-this-summer-heres-how-to-prepare-212443">promise of</a> long, hot months ahead, we may see our views about the warmer months start to shift.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1704325785627050136"}"></div></p>
<p>For some people, the coming months are not a celebration. They are something to fear, or feel sad about.</p>
<p>In particular, communities and emergency responders who have experienced bushfires or drought in the past may see rising levels of <a href="https://search.informit.org/doi/pdf/10.3316/ielapa.588776016823324">stress and anxiety</a> as they face the months ahead.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/here-comes-the-sun-how-the-weather-affects-our-mood-19183">Here comes the sun: how the weather affects our mood</a>
</strong>
</em>
</p>
<hr>
<h2>How’s this spring different?</h2>
<p>In recent weeks, the Australian Bureau of Meteorology has <a href="http://www.bom.gov.au/climate/enso/">declared</a> two climate events are now under way: <a href="https://theconversation.com/explainer-el-nino-and-la-nina-27719">El Niño</a> and a positive <a href="http://www.bom.gov.au/climate/iod/">Indian Ocean Dipole</a>. </p>
<p>These events predict warmer, drier conditions through to summer, as well as more intense heatwaves, bushfires and droughts.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1703999811136205005"}"></div></p>
<p>In temperate and subtropical regions, our summers are on average <a href="https://australiainstitute.org.au/wp-content/uploads/2020/12/P834-Out-of-Season-WEB.pdf">becoming</a> hotter and longer, and winters are becoming warmer and shorter. Climate change is the <a href="https://www.csiro.au/en/research/environmental-impacts/climate-change/climate-change-information">primary driver</a> of these shifts.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-el-nino-and-la-nina-27719">Explainer: El Niño and La Niña</a>
</strong>
</em>
</p>
<hr>
<h2>What happens to our mood as the temperature rises?</h2>
<p>Hotter temperatures and prolonged heat is linked to <a href="https://link.springer.com/article/10.1007/s40641-019-00121-2">aggression</a> and <a href="https://link.springer.com/article/10.1007/s00420-010-0534-2">higher rates</a> of emergency hospital admissions due to health conditions, heat-related injuries, and mental health concerns. </p>
<p>After an extreme weather event or disaster, rates of anxiety, depression and post-traumatic stress <a href="https://pubmed.ncbi.nlm.nih.gov/33227944/">rise</a>. </p>
<p>Many Australians have already experienced the psychological and physical <a href="https://journals.sagepub.com/doi/abs/10.1177/00048674221107872">impacts</a> of bushfires, droughts, floods and heatwaves. </p>
<p>For some communities and individuals, experiencing these types of events may mean they are <a href="https://www.sciencedirect.com/science/article/pii/S0887618520301110">more</a> resilient or prepared for the future. For others, the anticipation of rising heat or other climatic threats may cause <a href="https://www.mdpi.com/1660-4601/10/1/1">concern</a>. They may also prompt <a href="https://journals.sagepub.com/doi/full/10.1177/00048674221107872">pre-traumatic stress</a> – the stress that comes ahead of expected loss or trauma.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1466521425888620550"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/worried-about-heat-and-fire-this-summer-heres-how-to-prepare-212443">Worried about heat and fire this summer? Here's how to prepare</a>
</strong>
</em>
</p>
<hr>
<h2>Anxiety, anger and sadness</h2>
<p>As climate-related events become more widespread, people may also become increasingly affected by feelings such as anxiety, anger and sadness.</p>
<p><a href="https://www.nature.com/articles/s41558-021-01251-y">Climate anxiety</a> refers to the fear, dread and worry about climate change. Anxiety can be a helpful response as it allows us to prepare and respond to future threats. For instance, climate anxiety <a href="https://www.sciencedirect.com/science/article/pii/S0272494422001323">may help prompt</a> pro-environmental behaviour and climate action, such as attending a protest. But this type of anxiety can also become <a href="https://www.sciencedirect.com/science/article/pii/S0887618520300773">overwhelming</a>.</p>
<p>The loss of wildlife and nature due to bushfires can leave people feeling <a href="https://www.mdpi.com/1660-4601/19/4/2461">grief</a> over what’s lost, and <a href="https://www.sciencedirect.com/science/article/pii/S2667278221000018">anger</a> about the lack of action to prevent these losses.</p>
<p>Losses could also be more personal, including damage to health, livelihoods, homes, or even the ability to do enjoyable outdoor activities, such as playing sports or exercising outside.</p>
<p>Another experience, solastalgia, is the “homesickness you have when you are still at home”. <a href="https://pubmed.ncbi.nlm.nih.gov/18027145/#:%7E:text=As%20opposed%20to%20nostalgia%2D%2D,connected%20to%20their%20home%20environment.">Researchers suggest</a> solastalgia is a type of distress when someone perceives negative changes and gradual deterioration to their own home environment. These feelings could arise when we notice seasonal and environmental changes to the places we love and call home.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/youre-not-the-only-one-feeling-helpless-eco-anxiety-can-reach-far-beyond-bushfire-communities-129453">You're not the only one feeling helpless. Eco-anxiety can reach far beyond bushfire communities</a>
</strong>
</em>
</p>
<hr>
<h2>But there are things you can do</h2>
<p>Heading into the hotter months, strong <a href="https://www.sciencedirect.com/science/article/pii/S0887618520301110">community</a> support, cohesion and preparedness may be especially important. There are also things you can do to maintain and manage your mental health and wellbeing. Though more research is needed to understand which strategies work best, health professionals <a href="https://headspace.org.au/assets/Factsheets/headspace_how-to-cope-with-the-stress-of-natural-disasters_Fact-Sheet_FA01_DIGI-1.pdf">suggest</a>:</p>
<ul>
<li><p>connecting with others, especially people you trust and who support your wellbeing </p></li>
<li><p>finding ways to connect with your community either in person (for example, through <a href="https://theconversation.com/how-community-gardening-could-ease-your-climate-concerns-211316">community gardening</a>) or online (for example, via discussion groups)</p></li>
<li><p>being mindful of your physical and psychological safety (for instance, especially during climate-related events) and, if you need it, seeking professional support</p></li>
<li><p>taking a break from distressing media content when needed. </p></li>
</ul>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/keeping-your-cool-in-a-warming-world-8-steps-to-help-manage-eco-anxiety-212174">Keeping your cool in a warming world: 8 steps to help manage eco-anxiety</a>
</strong>
</em>
</p>
<hr>
<p>Understandably, people may continue to be anxious about the seasons to come with the ongoing threat of climate change.</p>
<p>To avoid becoming overwhelmed, you can also respond to and channel your distressing feelings. You can <a href="https://link.springer.com/article/10.1007/s12144-022-02735-6">take part in</a> community-led climate action projects, and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0272494419301185">spend time outdoors</a> and in nature (even for <a href="https://www.tandfonline.com/doi/abs/10.1080/17439760.2018.1557242">short bursts of time</a>). </p>
<p>These actions might help uphold the positive links between wellbeing and nature, no matter the season.</p>
<hr>
<p><em>If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14.</em></p><img src="https://counter.theconversation.com/content/213643/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tara Crandon receives funding from the Child and Youth Mental Health group at QIMR Berghofer Medical Research Institute.</span></em></p>We’ve had an early start to the bushfire season and there’s more to come. No wonder spring isn’t always a celebration.Tara Crandon, Psychologist and PhD Candidate, QIMR Berghofer Medical Research InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2057202023-05-18T14:37:02Z2023-05-18T14:37:02ZDecolonize your garden: This long weekend, dig into the complicated roots of gardening — Listen<p>The May long weekend is the unofficial start of summer. And for those of you with home gardens or access to community space, this is the weekend to dust off your gardening tools and visit the garden centre for the growing season ahead.</p>
<p>As we approach the start of gardening season, it’s good time to ask some questions about its origins.</p>
<p>Whether you plan to get marigolds, plant a vegetable garden or create a pollinator patch — all gardens have complicated roots. </p>
<p>In fact, the practice of gardening is <a href="https://www.architectural-review.com/essays/the-coloniality-of-planting">deeply tied to colonialism</a> — from the <a href="https://www.noemamag.com/the-long-shadow-of-colonial-science">formation of botany as a science</a>, to the <a href="https://www.nature.com/articles/s41559-022-01865-1">spread of seeds, species and knowledge.</a> </p>
<iframe height="200px" width="100%" frameborder="no" scrolling="no" seamless="" src="https://player.simplecast.com/92c92d2a-9628-4da6-9b3f-8bf5ec67d7cf?dark=true"></iframe>
<p><em><a href="https://dont-call-me-resilient.simplecast.com/episodes/decolonize-your-garden-this-long-weekend-visit-the-complicated-roots-of-gardening-listen">In this episode of Don’t Call Me Resilient</a>, we explore the complicated roots of the garden, including who gets to garden. We also discuss practical tips about what to plant with an eye to Indigenous knowledge. We speak with researcher Jacqueline L. Scott and also chat with community activist, Carolynne Crawley, who leads workshops that integrate Indigenous teachings into practice.</em></p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=826&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=826&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=826&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1039&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1039&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526840/original/file-20230517-5572-g2q2yt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1039&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Watercolor illustration of Tulipa sylvestris in I Cinque libri di piante.</span>
<span class="attribution"><span class="source">Pietro Antonio Michiel, Venice ca. 1550–1576, Biblioteca Nazionale Marciana.</span></span>
</figcaption>
</figure>
<h2>Coveted tulips</h2>
<p>Some of the most recognizable plants today, such as <a href="https://www.smithsonianmag.com/history/there-never-was-real-tulip-fever-180964915/">tulips</a>, are the result of early colonial conquests. Originally found growing wild in the valleys where current China and Tibet meet Afghanistan and Russia, tulips were first cultivated in Istanbul as early as 1055. </p>
<p>Later, after they were hybridized and commodified by the Dutch, they became highly coveted status symbols because of their gorgeous, but fleeting, blooms. </p>
<p>Exploratory botanical voyages by colonial European powers were integral to the expansion of empire. These trips fueled the big business of collecting global plant samples and also led to the emergence of botany as a scientific discipline. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=465&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=465&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=465&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=585&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=585&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526841/original/file-20230517-21-yooz26.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=585&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">227 figures of plant anatomical segments with descriptive text. Botany. Plant anatomy. Plant morphology. Plants. Roots (Botany). Roots (Botany) – Morphology. Roots (Botany) – Anatomy. Rootstocks. Tubers. Leaves. Leaves – Morphology. Flowers – Morphology. Flowers. Fruit – Morphology. Bulbs (Plant anatomy). Plants – Variation. Botany – France. Stems (Botany).</span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<h2>Botanical gardens served as labs</h2>
<p>Botanical gardens played a key role, serving as the laboratories where plant specimens were organized, ordered and named. <a href="https://doi.org/10.1016/j.fsisyn.2021.100196">“Scientific objectivity”</a> asserted a Eurocentric point of view, disrupting and displacing Indigenous Knowledge and ecological practices. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=383&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=383&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=383&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526842/original/file-20230517-12607-80m0ex.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A 1913 illustrated depiction of African American people picking cotton.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:CottonpickHoustonWhere17.png">Jerome H. Farbar: 'Houston: Where Seventeen Railroads Meet the Sea.' Page 31/40, 'Cotton Pickers'</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The movement and transfer of plants around the world went hand in hand with the transportation of people to provide a labour force, through slavery and indentured servitude. </p>
<p>The plantation system cleared out local ecosystems and replaced traditional farming methods with growing cash crops — like <a href="https://www.nytimes.com/interactive/2019/08/14/magazine/sugar-slave-trade-slavery.html">sugar-cane</a>, <a href="https://thecorrespondent.com/222/the-history-of-tea-is-darker-than-a-builders-brew">tea</a> and <a href="https://www.vox.com/identities/2019/8/16/20806069/slavery-economy-capitalism-violence-cotton-edward-baptist">cotton.</a> These were products meant for European curiosities, markets and profit and not for the local populations.</p>
<h2>Plant and racial hierarchies</h2>
<p>This colonial system of <a href="https://open.oregonstate.education/cultivatedplants/chapter/colonialagriculture/">organizing agriculture</a> laid the groundwork for <a href="https://www.sapiens.org/biology/race-scientific-taxonomy/">categorizing people</a> in a similar way, establishing a social hierarchy which dehumanized non-Europeans, helping justify slavery and Indigenous genocide, and eventually leading to racial categories.</p>
<p>This history has shaped our current relationships to the land, and our gardens. It also informs beliefs about land ownership and access; who has a right to enjoy the land, versus who is expected to be working on it. Who has the literal and figurative space and freedom to garden?</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=435&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=435&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=435&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=547&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=547&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526848/original/file-20230517-13420-luw1sy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=547&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On the left is a lawn (Stephen Cobb/Unsplash) and on the right is a native plant garden in Streeterville, Chicago (Shutterstock).</span>
</figcaption>
</figure>
<h2>Shifting attitudes</h2>
<p>But the soil is shifting. There is a growing shift away from <a href="https://www.theglobeandmail.com/canada/article-is-it-time-to-decolonize-your-lawn/">the colonial status symbol of the lawn</a> and <a href="https://chatelaine.com/living/quiet-quitting-garden/">manicured gardens</a>, in favour of <a href="https://broadview.org/lorraine-johnson-interview/">pollinator-friendly</a> <a href="https://www.nytimes.com/2022/07/13/realestate/why-some-of-your-annuals-should-be-native-plants.html">native plants</a>. </p>
<p>There is also a growing understanding that <a href="https://broadview.org/grandfather-teachings-gardening/">centuries-old Indigenous land-based knowledge</a> and practices — like <a href="https://www.theguardian.com/us-news/2019/nov/21/wildfire-prescribed-burns-california-native-americans">controlled burns</a> — can help manage wildfires, and foster a more resilient landscape.</p>
<p>With concerns about our climate crisis growing, one of the possible avenues for <a href="https://theconversation.com/how-urban-gardens-can-boost-biodiversity-and-make-cities-more-sustainable-162810">creating more sustainable cities may very well lie in our gardens</a>.</p>
<p>Could we have an impact simply by thinking a little differently about the seeds we sow and the “weeds” we pull?</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=993&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=993&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=993&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1248&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1248&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526851/original/file-20230517-10717-ww5ofa.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1248&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Monarch butterfly on purple coneflowers.</span>
<span class="attribution"><span class="source">Jeffrey Hamilton/Unsplash</span></span>
</figcaption>
</figure>
<h2>Listen and Follow</h2>
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<h2>Resources</h2>
<p><a href="https://www.nationalobserver.com/2021/01/29/news/tiffany-traverse-rare-indigenous-seed-project">Tiffany Traverse on seeds and their endless power to give, heal and grow</a> - <em>Canada’s National Observer</em></p>
<p><a href="https://www.architectural-review.com/essays/the-coloniality-of-planting">The coloniality of planting: legacies of racism and slavery in the practice of botany</a> - <em>The Architectural Review</em></p>
<p><a href="https://www.noemamag.com/the-long-shadow-of-colonial-science/">The Long Shadow Of Colonial Science</a> - <em>Noema Magazine</em></p>
<p><a href="https://www.theglobeandmail.com/canada/article-is-it-time-to-decolonize-your-lawn/">Is it time to decolonize your lawn?</a> - <em>Globe and Mail</em></p>
<p><a href="https://turtleprotectors.com">Turtle Protectors</a> in Toronto’s High Park</p>
<p><a href="https://gardeningoutloud.substack.com/p/guest-episode-1-spring-joy-with-ateqah">Spring joy with Ateqah Khaki</a> - <em>Gardening Out Loud</em></p>
<h2>From the archives - in The Conversation</h2>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-the-colonial-past-of-botanical-gardens-can-be-put-to-good-use-104786">How the colonial past of botanical gardens can be put to good use</a>
</strong>
</em>
</p>
<hr>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/director-of-science-at-kew-its-time-to-decolonise-botanical-collections-141070">Director of science at Kew: it's time to decolonise botanical collections</a>
</strong>
</em>
</p>
<hr>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-shortage-of-native-seeds-is-slowing-land-restoration-across-the-us-which-is-crucial-for-tackling-climate-change-and-extinctions-199049">A shortage of native seeds is slowing land restoration across the US, which is crucial for tackling climate change and extinctions</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526355/original/file-20230515-24343-lszaxe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An aerial view of small green seedlings in pots.</span>
<span class="attribution"><span class="source">Markus Spiske PG/Unsplash</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/205720/count.gif" alt="The Conversation" width="1" height="1" />
As we approach the start of gardening season, it’s a good time to ask some questions about what to plant and who gets to plant.Vinita Srivastava, Host + Producer, Don't Call Me ResilientAteqah Khaki, Associate Producer, Don't Call Me ResilientLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2053342023-05-12T15:17:55Z2023-05-12T15:17:55ZDrought recedes in Britain after a wet spring – but much of Europe is parched<p>Be careful what you wish for. Britain’s seesaw rainfall patterns that began last winter have continued, with an on-off pattern of <a href="https://rdg.today/hosepipe-bans-could-be-enforced-after-remarkably-dry-winter/">dry</a> and then wet months for many areas.</p>
<p>In the south of England, last year’s drought was still affecting parts of the UK <a href="https://www.gov.uk/government/news/plan-now-to-avoid-drought-next-summer-national-drought-group-told">in early December</a>, with stores of water in reservoirs and groundwater lower than usual. Seemingly endless rain followed over Christmas and January, before <a href="https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2023/february-and-winter-stats">one of the driest Februaries on record</a> led to renewed <a href="https://www.gov.uk/government/news/one-hot-dry-spell-away-from-drought-returning-this-summer-national-drought-group-warns">warnings of drought</a>.</p>
<p>Hydrologists like me were pointing to <a href="https://www.bbc.co.uk/programmes/m001k0dq">low stocks of water in aquifers and rivers</a>, raising our eyebrows and sucking our teeth like car mechanics faced with a blown gasket. We need rain, we said, or reservoirs will dry up, crops will fail, and restrictions on how much water people can use, like hosepipe bans, may be necessary.</p>
<p>Well, we got it. England and Wales had their <a href="https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2023/march-2023-weather-review">wettest March in 40 years</a> and April continued the wet trend, although rainfall was more patchy. The reason was that the jet stream, the fast-flowing and meandering air current high up in the atmosphere which governs a lot of weather in Britain and north-west Europe, shifted south. This pulled cold air down from the Arctic in early March. </p>
<p>Much of Britain shivered under this blanket of cold, with snow and ice blocking roads and closing schools. Then westerly winds returned, pulling cyclonic weather systems off the ocean in a stream of wet weather.</p>
<p>In April, the jet stream shifted north, leading to unsettled weather and lots of the April showers that we tend to expect of a British spring.</p>
<p>The result is that the hydrology of England and Wales – the state of the water supply in rocks, soils, rivers and reservoirs – has bounced back. In some areas, it has bounced back so quickly that there have been floods. The heavy thunderstorms of recent days in parts of south-west England caused flash flooding of the kind that scientists <a href="https://theconversation.com/intense-downpours-in-the-uk-will-increase-due-to-climate-change-new-study-200385">expect to see more</a> of as a result of the warmer atmosphere created by climate change.</p>
<p>Parts of southern England now have higher levels of water in rivers and aquifers than we would expect at this time of year. Kent had almost <a href="https://www.southernwater.co.uk/water-for-life/regional-rainfall">twice the expected rainfall</a> for April. Of course, this raises the risk of flooding – and almost any part of the country can flood, especially from such sudden, intense downpours falling onto concreted urban areas or saturated ground.</p>
<p>Scotland offers an interesting counterpoint. With only average rainfall over the past couple of months, parts of the country remain dry, with low river flows in the north heading into summer. Other regions look more normal for this time of year.</p>
<h2>The European drought continues</h2>
<p>The drought has been broken in much of the UK. But other parts of western Europe, which the British Isles had been sharing dry conditions with, remain parched. Spain and Portugal are seriously water-stressed, as is southern France and northern Africa. </p>
<p>As supermarket shoppers in the UK can attest, this has hit supplies of fresh fruit and vegetables in recent months. Spain’s grain harvest, one of its key crops for many farmers, <a href="https://www.euronews.com/green/2023/04/19/drought-threatens-grain-harvests-in-spain">now appears threatened</a>, with soils unable to sustain growth.</p>
<p>The long-running drought across Europe means that some major rivers continue to have low flows. The Po in north Italy and the Rhine, the arteries of western European industry, are both still down on where they should be.</p>
<p>When they are disrupted by flood or drought, big rivers that flow across international borders can heighten political and economic tensions. Low water levels in Europe have disrupted electricity supplies from normally reliable hydroelectric plants and some transport of materials and goods along the Rhine has had to shift to road and rail.</p>
<p>As in Britain, the risk of sudden heavy rain can easily cause dangerous flooding, even while drought continues. Two people recently died in northern Italy when floods caused by exceptional downpours saw rivers swell dangerously. Yet, after months of dry conditions beforehand, the same region may still be in drought.</p>
<h2>El Niño returns</h2>
<p>The climate of the British isles has always been variable. Perhaps the last year indicates that it is now extremely variable. When we think of variable British weather, this usually means rain when you don’t want it – such as when you’re <a href="https://news.sky.com/video/kings-coronation-royal-fans-scramble-for-ponchos-in-the-rain-12874340">trying to crown a king</a>. But variable weather increasingly implies temperature. </p>
<p>The summer of 2022 broke records for heat (temperatures in England topped 40°C for the first time). And we are now facing a situation in which El Niño – the major pattern of ocean currents and temperatures in the equatorial Pacific – is <a href="https://theconversation.com/four-possible-consequences-of-el-nino-returning-in-2023-198105">shifting into a positive, warming phase</a>. This will likely mean that background global heating, which has continued to build up in the atmosphere and oceans, will return with gusto in the next year or two. The extremes are here to stay.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
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<p class="fine-print"><em><span>Hannah Cloke advises the Environment Agency, the European Centre for Medium-range Weather Forecasts, the Copernicus Emergency Management Service, local and national governments and humanitarian agencies on the forecasting and warning of natural hazards. She is a member of the UKRI Natural Environment Research Council, a fellow of the European Centre for Medium-range Weather Forecasts and a fellow of the Centre for Natural Hazards & Disaster Science in Sweden. Her research is funded by the UKRI Engineering & Physical Sciences Research Council, the UKRI Natural Environment Research Council and the Foreign, Commonwealth & Development Office.</span></em></p>March 2023 was the wettest for 40 years in England and Wales.Hannah Cloke, Professor of Hydrology, University of ReadingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2025532023-03-30T15:20:57Z2023-03-30T15:20:57ZHay fever: why some people suffer from it and others don’t<figure><img src="https://images.theconversation.com/files/518169/original/file-20230329-28-d70vsm.jpg?ixlib=rb-1.1.0&rect=0%2C11%2C7360%2C4891&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/vibrant-blonde-middle-aged-woman-sneeze-622469891">Octa corp/Shutterstock</a></span></figcaption></figure><p>While the arrival of spring brings blooming flowers and trees, it also marks the beginning of allergy season for many people. Those who suffer from hay fever may start to notice <a href="https://www.nhs.uk/conditions/hay-fever/">familiar symptoms</a> such as sneezing, itchy eyes and a runny nose. </p>
<p>Hay fever, also known as allergic rhinitis, affects up to <a href="https://europepmc.org/article/med/17153005">42% of people</a> and can significantly impact their quality of life during the spring and summer months.</p>
<p>When a person with hay fever comes into contact with an allergen (pollen), their immune system mistakenly identifies it as a threat and produces an antibody called <a href="https://bestpractice.bmj.com/topics/en-gb/232">immunoglobulin E</a>, or IgE, to neutralise it. The IgE antibodies then attach themselves to a type of immune cells called mast cells, which are found in the nose, eyes and lungs. </p>
<p>When the allergen comes into contact with the IgE antibodies on the mast cells, it triggers the release of histamine and other proteins, causing inflammation and the symptoms of hay fever.</p>
<p>But why do so many people get hay fever, while others don’t? There are a range of factors at play.</p>
<h2>Genetics, immunity and the environment</h2>
<p>Genetic factors play a significant role in determining a person’s <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3151648/">susceptibility to hay fever</a>. Several genes, including those involved in immune system regulation and response, have been linked to an increased risk of developing hay fever. </p>
<p>Research has shown that the heritability – that is, the degree to which differences in people’s genes account for variations in their traits – ranges from <a href="https://www.frontiersin.org/articles/10.3389/fgene.2020.00270/full">33% to 91%</a> for hay fever. So, if people in your family have hay fever, you’re more likely to have it too.</p>
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Read more:
<a href="https://theconversation.com/do-i-have-covid-or-hay-fever-heres-how-to-tell-188030">Do I have COVID or hay fever? Here’s how to tell</a>
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<p>Some people’s immune systems <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573758/">may overreact to allergens</a>, leading to an allergic response and the development of hay fever. In fact, having other allergies, asthma, allergic dermatitis or eczema can <a href="https://www.mayoclinic.org/diseases-conditions/hay-fever/symptoms-causes/syc-20373039">increase your risk</a> of developing hay fever.</p>
<p>Environmental factors such as exposure to <a href="https://acaai.org/allergies/allergic-conditions/hay-fever/">air pollution, tobacco smoke and other irritants</a> may also make a person more susceptible to hay fever. This can be due to damage to the nasal passages and respiratory system, making it easier for allergens to enter the body and trigger an allergic response. Similarly, <a href="https://bmcpediatr.biomedcentral.com/articles/10.1186/1471-2431-10-61">exposure to second-hand smoke</a> in early life is a risk factor for later development of hay fever.</p>
<p>Some people may be <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5346329/">exposed to allergens</a> more frequently or in larger amounts than others, making them more susceptible to developing hay fever. This can be due to living in an area with high levels of pollen or being exposed to certain allergens at work, for example.</p>
<h2>Why can symptoms be worse in some seasons more than others?</h2>
<p>The amount of pollen or other allergens in the air can vary from year to year and season to season. In some years, the pollen count may be higher, leading to more severe hay fever symptoms.</p>
<p>Weather conditions, such as temperature, humidity and wind, <a href="https://link.springer.com/article/10.1007/s00484-017-1457-3">can affect</a> the amount and distribution of pollen in the air. A rainy spring may wash away some of the pollen, while a warm, dry summer may lead to more pollen production.</p>
<p>The body’s immune system can also change over time, which can affect how it responds to allergens. This means someone who had severe hay fever symptoms in the past may experience milder symptoms as they get older.</p>
<p>Indeed, hay fever can develop at any age, but it’s more common in <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/all.12002?casa_token=PWxI6ub0HtcAAAAA:a4GPzguEcA3aYK9Fu52clDTxPGFXsDuWml80jtViPIg8ilQDIcgOj58wwxcShXoz6q2br7L6eDAQ">children and young adults</a>. As a person ages, their immune system may become less reactive to allergens, leading to <a href="https://www.karger.com/article/Abstract/237398">a reduction in hay fever symptoms</a>.</p>
<figure class="align-center ">
<img alt="A young boy rubs his eyes." src="https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/518172/original/file-20230329-14-vosz9f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Hay fever is common in children.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/boy-rubbing-eye-child-pollen-allergy-2155315549">Dragana Gordic/Shutterstock</a></span>
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<p>People may be exposed to different allergens in <a href="https://link.springer.com/article/10.1007/s00484-017-1457-3">different years or seasons</a>, which can affect the severity of their symptoms. For example, someone who is allergic to grass pollen will be triggered at different times to those triggered by certain tree pollen.</p>
<p>Lifestyle factors such as stress, diet and exercise <a href="https://www.sciencedirect.com/science/article/pii/S0006899314014735?casa_token=H5zT4lQU1WwAAAAA:BiRy8aE-6zJT08dG5V5SDgo451zVC1wUFsAw67n0VwWXB58anEQ9n_rR5iiXyTLycoqT-2o">can affect the immune system</a> and may contribute to the severity of hay fever symptoms. For example, stress can weaken the immune system, making it <a href="https://www.immunology.theclinics.com/article/S0889-8561(10)00080-9/fulltext">more susceptible to allergens</a>. </p>
<p>Climate change is also altering the quantity and composition <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/all.14476">of pollen</a> that plants release, as well as the timing. Increasing temperatures and atmospheric carbon dioxide levels are causing some plants <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2222.2004.02061.x">to produce more pollen</a>, while other species are shifting their flowering periods to earlier in the year. This means pollen seasons are starting earlier, lasting longer, and becoming more intense.</p>
<h2>Tips for managing hay fever</h2>
<p><strong>Avoid allergens:</strong> Try to <a href="https://www.uptodate.com/contents/trigger-avoidance-in-allergic-rhinitis-beyond-the-basics">avoid exposure to allergens</a> that trigger your hay fever symptoms. This may mean staying indoors during high pollen counts or wearing a mask if you’re working outdoors.</p>
<p><strong>Use air filters:</strong> Consider using <a href="https://www.sciencedirect.com/science/article/pii/S0091674909013177?casa_token=CkTL0kWie5kAAAAA:yvBLfFgn9XJPlenxxkLdy4zPxxbXRorx0dDamOIaE6oYYlg4o_o0xn4Ay9IzbhcsJSpF1dE">Hepa (high-efficiency particulate air) air filters</a> in your home or workplace to help remove allergens from the air. </p>
<p><strong>Keep windows closed:</strong> <a href="https://www.nhs.uk/conditions/hay-fever/">Closing windows</a> during high pollen counts will prevent allergens from entering your home.</p>
<p><strong>Take antihistamines:</strong> These are <a href="https://www.nhs.uk/medicines/cetirizine/">medications</a> that help reduce hay fever symptoms by blocking the effects of histamine, which is released during an allergic reaction.</p>
<p><strong>Consider immunotherapy:</strong> <a href="https://www.ncbi.nlm.nih.gov/books/NBK279487/">Immunotherapy</a>, also known as allergy shots, can help reduce hay fever symptoms by desensitising your immune system to specific allergens over time.</p>
<p><strong>Manage stress:</strong> Stress <a href="https://journals.sagepub.com/doi/pdf/10.1177/1559827610395467?casa_token=FsgTLcz27JEAAAAA:7DCZvxNdzd184MqZ2VLQ5rmaZQ6vU00NUJ6UR8fLDeX6YrEBf43gst7eUMp30OrA5qc6hjAJfQ">can make hay fever symptoms worse</a>, so try to manage it through techniques such as meditation, yoga or deep-breathing exercises.</p>
<p>It’s important to talk to your doctor before starting any new medications or treatments for hay fever.</p><img src="https://counter.theconversation.com/content/202553/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Our genetics, immune systems and conditions in the environment around us can all play a role in susceptibility to hay fever.Samuel J. White, Senior Lecturer in Genetic Immunology, Nottingham Trent UniversityPhilippe B. Wilson, Professor of One Health, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2009752023-03-14T12:24:27Z2023-03-14T12:24:27ZClimate change threatens spring wildflowers by speeding up the time when trees leaf out above them<figure><img src="https://images.theconversation.com/files/514776/original/file-20230311-17-7x9lo1.jpg?ixlib=rb-1.1.0&rect=23%2C0%2C3970%2C2952&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Native wildflowers, such as these Dutchman’s breeches (_Dicentra cucullaria_) that bloom early in spring are losing access to sunlight as trees leaf out earlier.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/26pTuFq">Katja Schulz/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>For <a href="https://nativeplantherald.prairienursery.com/2020/04/spring-ephemerals-in-the-woodland/">short-lived spring wildflowers</a> such as <a href="https://www.wildflower.org/plants/result.php?id_plant=anqu">wood anemone (<em>Anemone quinquefolia</em>)</a> and <a href="https://www.wildflower.org/plants/result.php?id_plant=dicu">Dutchman’s breeches (<em>Dicentra cucullaria</em>)</a>, timing is everything. These fleeting plants, known as ephemerals, grow in temperate forests around the world, leafing out and flowering early in spring before the trees towering above them leaf out. Emerge too early, and it will still be winter; emerge too late, and it will be too shady under the forest canopy for essential photosynthesis to happen. </p>
<p>Over their evolutionary history, these plants have figured out the best timing for their survival. But climate change is altering spring growing conditions, and plant life is changing along with it. </p>
<p>There are many examples of plants shifting flowering time in response to warming temperatures, such as <a href="http://dx.doi.org/10.1088/1748-9326/ac6bb4">cherry blossoms opening earlier and earlier</a> each year. However, when one part of an ecosystem shifts, will all the organisms that depend on it successfully shift too? Or will they be out of luck? And what if interconnected species respond to change at different rates, leading to disruptions in long-standing ecological relationships?</p>
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<figcaption><span class="caption">Participants in the federally funded USA National Phenology Network collect, store and share data on the timing of life cycle events in plants and animals and how climate change is altering those cycles.</span></figcaption>
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<p>Researchers have been asking these types of questions about phenology – the timing of biological events – <a href="https://press.uchicago.edu/ucp/books/book/chicago/W/bo8829988.html">related to climate change</a> for years. But most studies have focused on plant-animal interactions, like pollinators coming out at the <a href="https://doi.org/10.1042/ETLS20190139">wrong time for flowers</a>. Far fewer have analyzed plant-plant interactions, such as spring ephemerals that need time to grow before trees leaf out above them and block the sunlight.</p>
<p><a href="https://www.rprimacklab.com/">Our research group</a> has investigated the mismatch between understory wildflowers and canopy trees around Concord, Massachusetts, using historical observations recorded by Henry David Thoreau, the author of “<a href="https://www.gutenberg.org/files/205/205-h/205-h.htm">Walden,” his classic account of life in the woods</a>. We found that trees in Concord were more sensitive to spring temperatures than wildflowers were, and that this resulted in earlier tree leaf-out that <a href="https://doi.org/10.1111/ele.13224">reduced available light in the understory</a>. </p>
<p>This finding was an important first step, but we wanted to know whether these patterns persisted in other temperate forests in North America and across the Northern Hemisphere. Our 2023 study shows that <a href="https://doi.org/10.1111/1365-2745.14021">the answer is yes</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A plant with small purple flowers on the forest floor." src="https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=509&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=509&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=509&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=640&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=640&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514778/original/file-20230311-16-lzomuu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=640&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Round-lobed hepatica (<em>Hepatica americana</em>) is an early-blooming wildflower with blue, white or pink flowers, most often found in shaded woodlands.</span>
<span class="attribution"><a class="source" href="https://plants.ces.ncsu.edu/plants/hepatica-americana/">Frtiz Flohr Reynolds/NC State Extension</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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</figure>
<h2>North American mismatches</h2>
<p>For this research we used specimens from herbariums – collections of plants that have been pressed, dried and cataloged. The plants we examined were collected across eastern North America over the past 100 years. We evaluated over 3,000 pressed plant specimens to chart leafing-out time for trees and flowering time for spring wildflowers. </p>
<p>The vast scale of this study was made possible because herbaria have digitized millions of photographs of plant specimens and <a href="https://naturalhistory.si.edu/research/botany/news-and-highlights/digitized">made them available online</a> over the past decade. Before this resource existed, researchers had to travel to many museums scattered around the country. </p>
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<figcaption><span class="caption">The herbarium at the Royal Botanic Gardens in Kew, England, is one of the world’s largest and supports genetic research on plants from around the globe.</span></figcaption>
</figure>
<p>Historical weather records are <a href="https://prism.oregonstate.edu">also available online now</a>. This allows researchers to determine spring temperatures for the year and place where each specimen was collected.</p>
<p>Our study enabled us to confirm the results of our work in Concord. We found that as temperatures warm, deciduous trees across eastern north America are advancing their leaf-out timing faster than native wildflowers are responding.</p>
<p>For example, during cooler springs with 24-hour average March and April temperatures of 41 degrees Fahrenheit (5 degrees Celsius), trees leafed out 13 days after native wildflowers. This gave the flowers almost two weeks of full sun on the forest floor. However, during warmer springs, with average temperatures of 58 F (15 C), trees leafed out only 10 days after native wildflowers. This gave the wildflowers about 25% less full sunlight time during which to photosynthesize. </p>
<p>As spring temperatures warm even further with climate change, we expect wildflowers will have even shorter periods of full sunlight. This can mean a sizable decrease in the flowers’ energy supply and ability to survive, grow and reproduce.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A pink three-lobed wildflower." src="https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514779/original/file-20230311-3323-eiamcv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Trilliums, like this <em>Trillium grandiflorum</em>, bloom from February through June across North America depending on their location.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Trillium_grandiflorum#/media/File:Trillium_grandiflorum_pink1.jpg">Eric Hill/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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</figure>
<p>We also observed that trees and wildflowers in the warmer southern part of their ranges advanced their leaf-out and flowering times faster, respectively, than those in colder northern locations. In these zones, we found greater timing differences between trees and wildflowers. This means the potential for phenological mismatch, where native wildflowers are more likely to be shaded out by trees, is greater in the southeast U.S. than in areas farther north.</p>
<h2>Parallels and differences on other continents</h2>
<p>For a 2022 study, we collaborated with colleagues from China and Germany to evaluate over 5,000 tree and wildflower specimens collected over the past 120 years. We wanted to see to whether the phenological mismatches that we documented in North America could also be found in temperate forests of <a href="https://doi.org/10.1038/s41467-022-34936-9">East Asia and central Europe</a>. </p>
<p>Our team found a common pattern across all three continents. Trees and wildflowers are active earlier now than in the past, and they are active earlier in warm years and places. </p>
<p>However, in a surprising twist, we didn’t see the North American pattern of trees being more sensitive than wildflowers on the other two continents. In Europe, wildflowers and canopy trees seemed to be shifting together over time. In Asia, the understory wildflowers were shifting more than the trees — meaning they might get more light, not less, in a warmer future.</p>
<p>The differences we found among the three regions were due primarily to variation in the sensitivities of the trees to temperature. Trees in eastern North America responded more strongly to temperature shifts, while Asian trees responded less strongly.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1633812385709408256"}"></div></p>
<p>These results suggest that eastern North American trees have become especially sensitive to temperature as a way of adapting to this region’s <a href="https://earthathome.org/hoe/ne/climate/#">highly variable climate</a>. In contrast, trees in East Asia are apparently more sensitive to other environmental cues, such as day length, when it comes to the timing of spring growth.</p>
<h2>Informing forest management</h2>
<p>Our results pose questions for further research. If spring temperatures aren’t the primary cues determining leaf-out and flowering times of trees and wildflowers in East Asia, what are those cues? How does the declining spring light window for wildflowers in eastern North America affect their energy budgets and ability to survive, grow and flower?</p>
<p>Another question is whether there are any practical management techniques, such as thinning overstory trees or removing invasive plants, that can help wildflowers deal with the ongoing challenges of climate change. Such strategies could help people appreciate and conserve the full range of plants in the forests we depend on and cherish around the world.</p><img src="https://counter.theconversation.com/content/200975/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard B. Primack receives funding from the National Science Foundation. </span></em></p><p class="fine-print"><em><span>Benjamin R. Lee receives funding from the National Science Foundation and Morton Arboretum</span></em></p><p class="fine-print"><em><span>Tara K. Miller received funding from the National Science Foundation. </span></em></p>Many beloved wildflowers bloom in early spring, while trees are still bare and the flowers have access to sunlight. Climate change is throwing trees and wildflowers out of sync.Richard B. Primack, Professor of Biology, Boston UniversityBenjamin R. Lee, Postdoctoral Fellow in Biology, University of PittsburghTara K. Miller, Policy Research Specialist, Repair Lab, University of VirginiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1940412022-11-09T00:25:16Z2022-11-09T00:25:16ZHay fever can sometimes be more serious than we think. This is why we should know our treatment options<figure><img src="https://images.theconversation.com/files/493724/original/file-20221107-11-xo27jm.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C7054%2C3537&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/sick-woman-sneezing-blowing-nose-photo-1366461485">shutterstock</a></span></figcaption></figure><p>Hay fever (also known as allergic rhinitis) is a catch-all term that covers a group of ailments that cause sneezing, a runny nose, and itchy and red eyes.</p>
<p>Hay fever affects <a href="https://www.aihw.gov.au/getmedia/f155276c-b1c1-4bb9-94de-e7e09555bce4/13567.pdf.aspx?inline=true">millions</a> of people in Australia. Ask your friends and colleagues about hay fever and chances are several will report they have it. However, they will probably describe different triggers, symptoms and <a href="https://www.allergy.org.au/patients/allergic-rhinitis-hay-fever-and-sinusitis/guide-to-common-allergenic-pollen">seasons</a> when it occurs. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1590076998306566145"}"></div></p>
<p>Although it may seem like more of an annoyance than anything else, uncontrolled hay fever can have <a href="https://www.sciencedirect.com/science/article/abs/pii/S0091674997800425">economic</a> and further health effects. </p>
<p>Hay fever can reduce people’s ability to concentrate, for example when driving or at <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3904041/">work</a> or <a href="https://pubmed.ncbi.nlm.nih.gov/17560637/">school</a>. This is made worse with hay fever also leading to <a href="https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/410859">disturbed sleep</a>, affecting <a href="https://aacijournal.biomedcentral.com/articles/10.1186/s13223-021-00615-5">mood</a>.</p>
<p>Nasal inflammation from allergies also has a concerning impact on an individual’s defences against infection. The inflammation from hay fever and the need to mouth breathe has a direct <a href="https://thorax.bmj.com/content/67/7/582.short">impact on asthma</a>, leading to worse symptom control and a greater risk of a flare-up that requires unscheduled health care.</p>
<p>To reduce these risks, a range of treatments are available. However, before considering treatment, we need to consider what’s going wrong and why.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/lush-grasslands-higher-allergy-risks-what-hay-fever-sufferers-can-expect-from-another-la-nina-season-189982">Lush grasslands, higher allergy risks – what hay fever sufferers can expect from another La Niña season</a>
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</em>
</p>
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<h2>What is hay fever?</h2>
<p>In addition to genetic factors, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6436881">environmental exposures</a> such as airborne pollutants can dramatically predispose people to allergies.</p>
<p><strong>Common causes</strong></p>
<p>Causes of hay fever fall in three main groups:</p>
<ul>
<li><p>seasonal: pollens and plant materials that give symptoms at certain times of the year. Calendar charts of the various pollens are available</p></li>
<li><p>perennial/symptoms year round: however clean your house is, you will be exposed to fungal spores and to faeces from dust mites feeding off your dead skin cells. That sounds unsettling enough, but they can both be potent allergens that can’t be effectively avoided</p></li>
<li><p>intermittent: most typically these are animals’ dead skin. It’s worth noting the culprits are molecules in saliva, sweat and urine, not hair.</p></li>
</ul>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/pollen-does-more-than-make-you-sneeze-it-can-cause-thunderstorm-asthma-even-if-youre-not-asthmatic-190235">Pollen does more than make you sneeze. It can cause thunderstorm asthma, even if you're not asthmatic</a>
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</em>
</p>
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<h2>What treatments are best for hay fever?</h2>
<p>Given these serious consequences, it’s reassuring to know there are effective treatments for hay fever. These range from common over-the-counter products to specialist medicines. </p>
<p><strong>Antihistamines</strong></p>
<p>Many people will immediately think of antihistamines for hay fever: by tablet, nasal spray or eye drops. Histamine is a key messenger chemical in the allergy process, but it isn’t the only one. Therefore, antihistamines alone are usually usually only sufficient to get on top of mild problems.</p>
<p>There are a large number of antihistamines available with a range of effectiveness. Although many are available without prescription, bear in mind some are sedating, and some are unsafe in pregnancy, or when you have certain cardiac conditions, and may clash with some other medicines.</p>
<p><strong>Nasal treatments</strong></p>
<p>Nasal sprays apply treatment directly to microscopic hairs in the nose, helpfully spreading the medicine around. Many people take over-the-counter nasal corticosteroid spray to dampen down inflammation. </p>
<p>As a physician I’ve found it’s common in clinic for people to say sprays “don’t work” for them but usually this is because they don’t take them properly. These <a href="https://pubmed.ncbi.nlm.nih.gov/29050548/">treatments</a> can take many days to work, and need to be taken regularly every day. The trick is: don’t sniff them (the medicine will end up in the back of your throat), or spray them onto the sensitive middle part of the nose, which can bleed.</p>
<p>Saline sinus rinses can be very helpful in clearing mucus, allergens and inflammatory material (snot, to you and me) before using other medicines. <em>Always</em> use sterile liquids for this or nasty sinus infections can occur.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/sneezing-with-hay-fever-native-plants-arent-usually-the-culprit-190336">Sneezing with hay fever? Native plants aren't usually the culprit</a>
</strong>
</em>
</p>
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<p><strong>Decongestants</strong></p>
<p>Decongestants might seem like a good idea when you can’t breathe, but are associated with a rebound worsening of swelling when they wear off (this has the excellent name of rhinitis medicamentosa). </p>
<p>As for many chemicals, if you take them long enough the body switches off its own supply (negative feedback) so when the drug is removed, the body is worse off. Think about how someone feels if they haven’t had a coffee all day and normally drinks four or five cups. There is a rebound of blood vessel dilation and mucus production. Use them sparingly.</p>
<figure class="align-center ">
<img alt="A person is standing outside using nasal spray. They wear glasses." src="https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493735/original/file-20221107-23-zcbtt7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A lack of success of allergy treatments such as nasal sprays are often due to them not being used correctly.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/man-africanamerican-ethnicity-using-nasal-spray-2155318875">shutterstock</a></span>
</figcaption>
</figure>
<h2>Prescribed therapies</h2>
<p>If your hay fever is more severe, your doctor could consider a course of higher-strength nasal steroid drops, but these aren’t to be used for longer than a month as they can cause erosion of the nasal lining. </p>
<p>Adding a medicine that acts on other key messengers of inflammation (leukotrienes), such as montelukast, can sometimes be helpful. These tablets are usually well tolerated but can have side effects such as headache which lead to their discontinuation. </p>
<p>Validated scores that ask a standard set of questions about aspects of someone’s symptoms (such as “SNOT-22”) are helpful in assessing who needs extra prescription-based treatment for hay fever and their response to it.</p>
<h2>Specialist treatments</h2>
<p>For people with hay fever alongside asthma or other allergic disease, there are now effective medicines that block messengers of allergy in a highly specific manner, such as the <a href="https://pubmed.ncbi.nlm.nih.gov/29355679/">monoclonal antibody</a> Dupilumab, and more are <a href="https://erj.ersjournals.com/content/52/suppl_62/PA5248">coming soon</a>. Although too costly to be prescribed in hay fever alone, they show our understanding of the relevant mechanisms has improved.</p>
<p>Giving people a regular small dose of something they are sensitised to can make their immune system more tolerant of it. This is often referred to as immunotherapy, and can be by regular tablet or injection. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/im-considering-allergen-immunotherapy-for-my-hay-fever-what-do-i-need-to-know-190408">I’m considering allergen immunotherapy for my hay fever. What do I need to know?</a>
</strong>
</em>
</p>
<hr>
<p>Although <a href="https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(21)00261-1/fulltext">potentially very helpful</a>, this treatment takes years and many people <a href="https://www.ingentaconnect.com/content/ocean/aap/2021/00000042/00000001/art00015;jsessionid=18yqw4ncvah8.x-ic-live-01#">don’t complete their course</a>. The improvements seen are incremental rather than a complete <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6132438/">permanent resolution</a>.</p>
<hr>
<p><em>This article does not constitute specific medical advice. Please do speak to your GP, specialist or pharmacist about using the medicines mentioned here. You may also wish to review the helpful information and videos from <a href="https://asthma.org.au/about-asthma/triggers/hay-fever/">Asthma Australia</a></em></p><img src="https://counter.theconversation.com/content/194041/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Blakey and/or his employer has received funding for research or educational activities from companies that produce treatments for asthma, including Astra Zeneca, Boehringer Ingelheim, Chiesi, GSK, Novartis, Sanofi and Teva. He is affiliated with Asthma Australia and Asthma WA in a medical advisory capacity for which his organisation receives income. He is the WA branch president of the Thoracic Society of Australia and New Zealand. None of these entities had any input into or influence on this article.</span></em></p>Hay fever treatment options range from common over-the-counter products to specialist medicines.John D Blakey, Adjunct Clinical Associate Professor - Curtin Medical School, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1908852022-10-19T20:31:02Z2022-10-19T20:31:02ZWhat a buzzkill: Early-ending winters disrupt bumblebee slumber<figure><img src="https://images.theconversation.com/files/488402/original/file-20221006-15-vb3ccq.jpg?ixlib=rb-1.1.0&rect=92%2C105%2C4294%2C2621&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bees that can adapt to the changing climate around us offer hope for more research and better policy and conservation efforts.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Gardeners across <a href="https://doi.org/10.1126/science.aax8591">North America and different parts of the world</a> have been growing worried over an eerie quiet settling over their gardens — a silence caused by the missing buzzing of bees. </p>
<p>With the increasing use of land for development and climate change worsening the bee disappearance globally, these gardeners have had to painstakingly transfer pollen grains from flower to flower with a paintbrush, simulating the <a href="https://www.towergarden.ca/blog.read.html/en/2015/6/flowers_but_no_fruit.html">process of pollination necessary for fruit or vegetable production</a>. </p>
<p>Losing these bees and other pollinators is no mere inconvenience, but a far broader challenge that is evolving with the changes in their environment.</p>
<p>In a recent research paper, <a href="https://science.uottawa.ca/biology/people/kerr-jeremy-t">my colleague Jeremy Kerr</a> and I found that <a href="https://doi.org/10.1016/j.biocon.2022.109675">72 per cent of native bumblebee species in North America are ending their winter hibernation much earlier</a>. While these bees have been timing their emergence to earlier spring onsets, the rest face the threat of extinction. </p>
<h2>Early wake up call</h2>
<p>Since the 1970’s, climate stressors including the increased rate of warming, earlier onset of spring and more unpredictable extreme weather events have added <a href="https://doi.org/10.1073/pnas.2023989118">new and severe challenges to the agricultural sector — and the pollinators it relies on</a>.</p>
<figure class="align-center ">
<img alt="A pollen covered bee." src="https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490570/original/file-20221019-20-xcjdui.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Bumblebee queens hibernate in the winter and search for pollen and nectar after waking up hungry and in need of energy.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Bees are extremely sensitive to environmental change. The changing climate increases the likelihood of an <a href="https://doi.org/10.1098/rspb.2012.1051">earlier end to winter and, thus, early flowering of spring plants</a>. These flowers are essential food sources for bumblebee queens that hibernate in the winter and search for pollen and nectar after <a href="https://www.bumblebeeconservation.org/lifecycle/">waking up hungry and in need of energy</a>.</p>
<p>The survival for those emerging from hibernation before the arrival of spring flowers — their main food source — is unlikely. This leads to smaller colonies with lower odds of persisting in the following years. </p>
<p>However, bumblebees that sync with the changing timing of spring take full advantage of the season’s floral resources and are more likely to thrive over time.</p>
<h2>In sync with climate change</h2>
<p>Our research found that many native bumblebee species in North America are adapting to the changing climate by cutting their hibernation period short.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A bee digging the ground." src="https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490569/original/file-20221019-17-tn5ks7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bumblebee queens find shelter in warm places like underground burrows and hibernate all through the winter.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>We examined the relationship between climate and bumblebee spring emergence using records from museum collections across North America. After studying 17,000 individual bees across 21 species, we found that the climate influenced the spring emergence patterns of 15 species. </p>
<p>Species including the Rusty-patched bumblebee (<em>Bombus affinis</em>) — <a href="https://www.xerces.org/endangered-species/species-profiles/at-risk-invertebrates/bumble-bees/rusty-patched-bumble-bee">a species that is important to crop pollination but facing extinction across North America</a> — and the Half-black bumblebee (<em>Bombus vagans</em>) failed to keep up with the seasonal changes. Landscape fragmentation, pesticides and diseases from commercial bee colonies compounded these native species’ survival risk. </p>
<p>On the other hand, bee species like the <em>Bombus pensylvanicus</em>, <em>Bombus melanopygus</em> and <em>Bombus huntii</em> successfully tracked the early arrival of spring and woke up from their winter hibernation in time to feast on the early-blooming flowers.</p>
<p>As there are about 40 native species in North America, this research stresses the need for more research and better conservation of these economically valuable pollinators.</p>
<h2>Who runs the world? Bees!</h2>
<p>Like canaries in a coal mine, <a href="https://beegratefulenactus.com/2020/12/13/bees-as-bioindicators-a-tool-to-measure-environmental-pollution/">the dwindling bee presence is an indicator of deteriorating environmental quality</a>.</p>
<p>The agriculture industry, which takes up approximately <a href="https://ourworldindata.org/">38 per cent of our land surface</a>, heavily relies on these pollinators to thrive. The production of coffee, kiwis, blueberries, pumpkins, tomatoes and vanilla depends on pollination by bees, while other crops like bananas <a href="https://www.pollinator.org/pollinated-food">benefit from pollinators like birds and fruit bats</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/YZCoX9tsT1E?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The global agriculture industry heavily relies on bee pollinators.</span></figcaption>
</figure>
<p><a href="https://www150.statcan.gc.ca/n1/daily-quotidien/190730/dq190730a-eng.htm">Agriculture contributes $49 billion</a> to the Canadian economy and over <a href="https://www.ers.usda.gov/data-products/ag-and-food-statistics-charting-the-essentials/ag-and-food-sectors-and-the-economy/">US$1 trillion</a> to the U.S. economy. </p>
<p>However, the conversion of land from forests or meadows to crops and pasture and the use of pesticides is <a href="https://doi.org/10.1126/science.aaa7031">making these habitats increasingly unsuitable for many bees</a>. Pesticides are deadly to bees, and agricultural monocultures fail to provide consistent food sources for pollinators throughout the spring and summer.</p>
<p>Our diets consist of foods pollinated by bees. If some pollinators struggle to adapt to climate changes, many of our crops will yield far less fruit and vegetables, triggering food security challenges globally.</p>
<h2>The future of bees</h2>
<p>Our research highlights potential concern in those species that demonstrated decline over time and inability to match changes in the climate.</p>
<p>Given the importance of bees to our global economy and food safety, it is good news that some bees are matching changes in spring onset between years. It is crucial that we target conservation efforts towards those species that are faring worse. </p>
<p>Meanwhile, policies to protect our pollinators must continue to include <a href="https://www.canada.ca/en/health-canada/services/consumer-product-safety/pesticides-pest-management/growers-commercial-users/pollinator-protection.html">pest and pesticide regulation</a> and the protection of natural spaces, <a href="https://www.toronto.ca/services-payments/water-environment/environmentally-friendly-city-initiatives/reports-plans-policies-research/draft-pollinator-strategy/">even in our cities</a>.</p>
<p>Research studies like this can help policy-makers and species conservation authorities <a href="https://doi.org/10.1038/d41586-018-06038-4">find effective and long-lasting ways of protecting the biodiversity of our planet for future generations.</a></p><img src="https://counter.theconversation.com/content/190885/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Olga Koppel does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Seventy-two per cent of native bumblebee species in North America are cutting their winter hibernation short by timing their emergence to earlier spring onsets.Olga Koppel, PhD Candidate in Conservation Biology, L’Université d’Ottawa/University of OttawaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1904382022-09-29T03:47:02Z2022-09-29T03:47:02ZExiled in LA: Gavin Lambert’s ‘beautiful and tarnished’ child stars, screenwriters and failed mystics<figure><img src="https://images.theconversation.com/files/485005/original/file-20220916-22-x8yc3w.jpg?ixlib=rb-1.1.0&rect=0%2C8%2C2810%2C1154&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Inside Daisy Clover, Warner Bros (1965).</span> <span class="attribution"><span class="source">IMDB</span></span></figcaption></figure><p>September in Melbourne finds me melancholy. The sun is bright but the wind is cold; the blossom is out but the winter sads hold fast. </p>
<p>It is around this time that I return to my Lamberts – three quiet, perfect books by Gavin Lambert, the English film critic who decamped for Los Angeles in the 1950s and chronicled the beautiful and the tarnished with equal clear-eyed, curious affection. The books are: <a href="https://www.goodreads.com/book/show/1208178.The_Slide_Area">The Slide Area</a> (1959), <a href="https://www.goodreads.com/en/book/show/408316.Inside_Daisy_Clover">Inside Daisy Clover</a> (1963) and <a href="https://www.simonandschuster.com/books/The-Goodby-People/Gavin-Lambert/9781946022448">The Goodby People</a> (1971). Along with <a href="https://www.goodreads.com/en/book/show/1193585.Running_Time">Running Time</a> (1982) they make up Lambert’s “Hollywood Quartet”. </p>
<p>If I’m melancholy around this time, I am also psychically open. September is for tarot spreads and house moves. It is in this winsome waiting month that I am most able to transport myself into narrative – and there is no place I would rather roam than Lambert’s L.A., with its mouthy <a href="https://theconversation.com/child-stars-the-power-and-the-price-of-cuteness-189444">child stars</a>, lonely screenwriters, “failed mystics, rootless sun-worshippers [and] exiles from the harsher realities of a different civilisation”. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/blonde-joyce-carol-oates-epic-marilyn-monroe-novel-captures-the-violence-of-celebrity-myth-making-184462">Blonde: Joyce Carol Oates' epic Marilyn Monroe novel captures the violence of celebrity myth-making</a>
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<h2>Inside Daisy Clover</h2>
<p>I came to Inside Daisy Clover first. I discovered it in when I was living in England, and I’m sure the when – being overseas, feeling like a true citizen of the world – has deepened my attachment to it. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=878&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=878&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=878&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1103&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1103&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485007/original/file-20220916-24-x8yc3w.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1103&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">American first edition, 1963.</span>
<span class="attribution"><span class="source">Badger Books</span></span>
</figcaption>
</figure>
<p>But there is also Daisy’s voice – tough, kooky and full of longing. Daisy is an adolescent fantasy figure, “pushing fourteen”, precocious and hectic. She lives with her mother “The Dealer” (so called because she usually has several games of solitaire going at once) in their trailer at Playa del Rey, “a cockeyed dump between two other cockeyed dumps called Hermosa Beach and Venice”. </p>
<p>Daisy’s pastimes include keeping an eye on her mother, moonbathing, and thinking about S-E-X, but what she really loves is the recording booth at the old pier at Venice, “I pay my twenty-five cents […] and I go inside and face this old man with a nervous twitch who works the machine and I SING.”</p>
<p>At first, Daisy keeps her singing to herself, but as The Dealer grows more unhinged she turns outward. When Daisy enters the Magnagram Studios talent contest, Raymond Swan, studio boss, and his icy wife Melora, send a limousine. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/rt2vPf9SEQo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Natalie Wood, as Daisy Clover, sings.</span></figcaption>
</figure>
<p>Daisy’s social skills are negligent. She turns up to her screen test for Little Annie Rooney wearing “a sickening little white number with too many flounces”. She faints during her audition, shocked by the heat and bright lights, but is somehow able to transcend the moment and blow everyone away. A Star is Born! </p>
<p>Things move swiftly. Daisy’s hated sister Gloria steps in as her guardian and the Dealer is put in a sanitorium. Daisy becomes the “Orphan Songbird”. Production begins and it’s all work-work-work and sometimes Benzedrine. First one film, then another. Daisy has little agency, and no friends aside from her Magnagram “family” – the Swans, her dodgy director, assorted film crew, and her literature teacher, Caroline, who tells her “a person with imagination is also a person with some degree of madness”.</p>
<p>At her first company Christmas party, Daisy meets up-and-coming actor, Wade Lewis, who is older, alcoholic and in the closet. His preferred methods of communication are <a href="https://www.npr.org/2019/08/05/747738120/how-bessie-smith-influenced-a-century-of-popular-music">Bessie Smith</a> records and grand gestures. “Refuse to do it their way,” he says, against the Swans and the system. “Their way is an insult to human dignity.” Daisy pursues Wade, even though it means losing everything. But the way she sees it, she already has lost everything. </p>
<p>For much of the novel, her dream is simple – freedom – just her and Wade and the Dealer in a house by the beach. It is only when Wade abandons her after their “Hollywood” wedding that she realises a new dream is in order. And then it is only when she abandons the movies, the life that has been built around her talent, that she finds freedom and becomes herself again. </p>
<p>“In America,” Lambert wrote in The Slide Area, “Illusion and reality are still often the same thing. The dream is the achievement, the achievement is the dream.”</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/natalie-wood-nothing-can-bring-back-the-hour-of-splendor-in-the-grass-91305">Natalie Wood: Nothing can bring back the hour of Splendor in the Grass</a>
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</em>
</p>
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<h2>Hollywood on the cusp of change</h2>
<p>Inside Daisy Clover perfectly describes a moment in time, when Hollywood was on the cusp of change, and the new moralities of the 1960s were edging out the old ways. Lambert was there for the end of the studio system. He left the bleak of England to become <a href="https://en.wikipedia.org/wiki/Nicholas_Ray">Nicholas Ray</a>’s protege in 1955, and went on to a long career as screenwriter, novelist and biographer. </p>
<p>His friend and subject Natalie Wood plays Daisy in the film adaptation of <a href="https://www.imdb.com/title/tt0059314/?ref_=fn_al_tt_1">Inside Daisy Clover</a> – it’s hammier than I want it to be, but I’d still have it over nothing – and Robert Redford plays the elusive Wade. Redford was reportedly not happy about his character being depicted as strictly gay. </p>
<p>In the film Wade simply disappears, but in the novel he is found living with his boyfriend in Mexico; later they run a hotel in Tangiers. Lambert ended up in Tangiers too, leaving L.A. because he felt it was time: he’d recieved a “message”. When asked if he considered himself an exile of L.A., he replied, “I consider myself an exile period.” </p>
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<figcaption><span class="caption">Natalie Wood as Daisy in the film of Inside Daisy Clover.</span></figcaption>
</figure>
<p>But I have found a kind of home in his books and in his characters. It is because even if they are lost, they are not resigned. And because no matter what happens to them, they are always seeking. Lambert’s description of the city also fits the dreamer’s pattern:</p>
<blockquote>
<p>something unfinished yet always remodelling itself, changing without a basis for change […] So much visible impatience to be born, to grow, such wild tracts of space to be filled …</p>
</blockquote>
<p>At her most lost point, Daisy Clover asks herself, “What’s the point of it all? Where’s it all going to end?” As with most things, it ends where it begins. Or rather, it ends with a metaphor of a shell Daisy’s been carrying around. It echoes long after she puts it to her ear, reminding her “the waves were always breaking somewhere else as well”.</p>
<p>For some people, to stop, to settle, to accept, is the same as dying. There is always something over there. The promise of it tantalises.</p><img src="https://counter.theconversation.com/content/190438/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simmone Howell does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When September melancholy hits Simmone Howell, she escapes the cold Melbourne spring to Gavin Lambert’s Los Angeles – and his ‘tough, kooky’ adolescent fantasy figure, Daisy Clover.Simmone Howell, Graduate researcher, English & Creative Writing, La Trobe UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1847302022-07-12T12:33:24Z2022-07-12T12:33:24ZLight pollution is disrupting the seasonal rhythms of plants and trees, lengthening pollen season in US cities<figure><img src="https://images.theconversation.com/files/473427/original/file-20220711-13-xmyjzd.jpg?ixlib=rb-1.1.0&rect=0%2C1772%2C3712%2C2160&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Some cities never sleep.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/light-trails-on-city-street-against-sky-at-night-royalty-free-image/1311603238">Noam Cohen/EyeEm via Getty Images</a></span></figcaption></figure><p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take about interesting academic work.</em></p>
<h2>The big idea</h2>
<p>City lights that blaze all night are profoundly disrupting urban plants’ phenology – shifting when their buds open in the spring and when their leaves change colors and drop in the fall. New research I coauthored shows how nighttime lights are <a href="https://doi.org/10.1093/pnasnexus/pgac046">lengthening the growing season in cities</a>, which can affect everything from <a href="https://doi.org/10.1001/jamanetworkopen.2020.7551">allergies</a> to local economies.</p>
<p>In our study, my colleagues and I analyzed trees and shrubs at about 3,000 sites in U.S. cities to see <a href="https://doi.org/10.1093/pnasnexus/pgac046">how they responded</a> under different lighting conditions over a five-year period. Plants use <a href="https://islandpress.org/books/ecological-consequences-artificial-night-lighting">the natural day-night cycle</a> as a signal of seasonal change along with <a href="https://doi.org/10.1073/pnas.1911117117">temperature</a>.</p>
<p>We found that artificial light alone <a href="https://doi.org/10.1093/pnasnexus/pgac046">advanced the date that leaf buds broke</a> in the spring by an average of about nine days compared to sites without nighttime lights. The timing of the fall color change in leaves was more complex, but the leaf change was still delayed on average by nearly six days across the lower 48 states. In general, we found that the more intense the light was, the greater the difference.</p>
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<p>We also projected the future influence of nighttime lights for five U.S. cities – Minneapolis, Chicago, Washington, Atlanta and Houston – based on different scenarios for future global warming and up to a 1% annual increase in nighttime light intensity. We found that increasing nighttime light would likely continue to shift the start of the season earlier, though its influence on the fall color change timing was more complex.</p>
<h2>Why it matters</h2>
<p>This kind of shift in plants’ biological clocks has important implications for the <a href="https://doi.org/10.1016/j.tourman.2018.08.021">economic</a>, <a href="https://theconversation.com/satellites-zoom-in-on-cities-hottest-neighborhoods-to-help-combat-the-urban-heat-island-effect-182925">climate</a>, <a href="https://doi.org/10.1001/jamanetworkopen.2020.7551">health</a> and <a href="https://doi.org/10.1098/rsbl.2014.0586">ecological</a> services that urban plants provide.</p>
<p>On the positive side, longer growing seasons could allow urban farms to <a href="https://doi.org/10.2134/jeq2013.01.0031">be active over longer periods of time</a>. Plants could also provide shade to cool neighborhoods earlier in spring and later in fall as global temperatures rise.</p>
<p>But changes to the growing season could also increase plants’ <a href="https://doi.org/10.1038/s41586-018-0399-1">vulnerability to spring frost damage</a>. And it can create a mismatch with the timing of other organisms, <a href="https://doi.org/10.1042/ETLS20190139">such as pollinators</a>, that some urban plants rely on.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Charts show the intensity of urban light in seven representative cities" src="https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=506&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=506&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473542/original/file-20220712-22-1d5slr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=506&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Urban light intensity varies among cities, and among neighborhoods within cities.</span>
<span class="attribution"><span class="source">Yuyu Zhou</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>A longer active season for urban plants also suggests an earlier and longer pollen season, which can exacerbate asthma and other breathing problems. A study in Maryland found a <a href="https://doi.org/10.1001/jamanetworkopen.2020.7551">17% increase</a> in hospitalizations for asthma in years when plants bloomed very early.</p>
<h2>What still isn’t known</h2>
<p>How the fall color timing will change going forward as night lighting increases and temperatures rise is less clear. Temperature and artificial light together influence the fall color in a complex way, and our projections suggested that the delay of coloring date due to climate warming might stop midcentury and possibly reverse because of artificial light. This will require more research.</p>
<p>How urban artificial light will change in the future also remains to be seen.</p>
<p>One study found that urban light at night had increased <a href="https://doi.org/10.1126/sciadv.1701528">by about 1.8% per year</a> worldwide from 2012-2016. However, many cities and states are <a href="https://www.ncsl.org/research/environment-and-natural-resources/states-shut-out-light-pollution.aspx">trying to reduce light pollution</a>, including requiring shields to control where the light goes and shifting to LED street lights, which use less energy and have <a href="https://doi.org/10.1111/1365-2664.12927">less of an effect</a> on plants than traditional streetlights with <a href="https://doi.org/10.1038/35036500">longer wavelengths</a>.</p>
<figure class="align-center ">
<img alt="Cars are parked on an old brick residential street at dusk with street lights and trees lining the sidewalks." src="https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473435/original/file-20220711-14-a2ls8a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Baltimore has been converting its streetlights to LED to save money on energy. LEDs also have less of an impact on plants.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cobblestone-street-and-fells-point-neighborhood-at-royalty-free-image/1179432549">Cyndi Monaghan via Getty Images</a></span>
</figcaption>
</figure>
<p>Urban plants’ phenology may also be influenced by other factors, such as carbon dioxide and soil moisture. Additionally, the faster increase of temperature at night compared to the daytime could lead to different day-night temperature patterns, which might <a href="https://doi.org/10.1016/j.agrformet.2019.107832">affect plant phenology in complex ways</a>.</p>
<p>Understanding these interactions between plants and artificial light and temperature will help scientists <a href="https://doi.org/10.1038/s41558-022-01331-7">predict changes in plant processes under a changing climate</a>. Cities are already serving as natural laboratories.</p><img src="https://counter.theconversation.com/content/184730/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yuyu Zhou receives funding from the College of Liberal Arts and Sciences at Iowa State University. </span></em></p>Artificial light is upending trees’ ability to use the natural day-night cycle as a signal of seasonal change.Yuyu Zhou, Associate Professor of Environmental Science, Iowa State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1812312022-04-21T18:44:57Z2022-04-21T18:44:57ZClimate change is altering the seasonal rhythm of plant life-cycle events<figure><img src="https://images.theconversation.com/files/458261/original/file-20220414-12-lyqvov.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Changes in climate affect the timings of various points in the life cycle of plants, including when flowers bloom in spring and when leaves wither in autumn.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>“<em>Si sta come d’autunno sugli alberi le foglie</em>.” </p>
<p>“We are like autumn leaves on branches,” <a href="https://cultura.biografieonline.it/soldati-ungaretti/">Italian poet Giuseppe Ungaretti wrote in his 1918 poem <em>Soldati</em></a> (Soldiers), on the tragedy of human life and war.</p>
<p>If the popular image of autumn is <a href="https://doi.org/10.1177%2F039219216201003804">decadence and nostalgia</a> after the summer heat, spring is the season of rebirth after the darkness and cold of winter. The transformative passing of seasons has historically represented a powerful mental image, rich in symbolism. The seasonal timings of biological events are also an essential aspect of <a href="https://doi.org/10.1016/j.tree.2007.04.003">plant adaptation</a> and can also be of crucial <a href="https://doi.org/10.1007/978-90-481-3335-2_4">economic relevance</a>. </p>
<p>However, as forest ecologists, we have observed that climate change has been modifying the timing of recurrent plant life-cycle events, thus critically affecting the ecosystem. </p>
<h2>The plant’s clock</h2>
<p>In spring, flowers bloom. In summer, fruits ripen. In autumn, leaves change colour and fall. In winter, plants rest. This is <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/phenology">phenology</a> — the study of the timing of recurring life-cycle events. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/W0jjyf7sRY8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The life-cycle of plants, animals and all life forms depends on the environment around them.</span></figcaption>
</figure>
<p>So how do plants recognize the passage of time and the right moment to accomplish growth and reproduction? Like people, plants have their own calendar. A plant’s clock is represented by cycles in the environmental conditions, and the timing of phenological events is <a href="https://doi.org/10.1111/gcb.14619">controlled by climate</a>. </p>
<p>Specifically, plants use a set of triggers to synchronize the timings of growth and reproduction with favourable environmental conditions. </p>
<p>Depending on the species, phenological events are triggered by temperature (autumn and winter chilling and spring warming), photoperiod (length of day), precipitation or, often, a combination of these.</p>
<h2>If climate changes, phenology changes</h2>
<p>Phenology is one of the most sensitive biological indicators of the changing climate. Under the progressive rise in temperature experienced in the last century and the variations in seasonal distribution of rainfall events, the <a href="https://doi.org/10.1111/gcb.14619">environmental triggers usually occur earlier and earlier</a>. </p>
<p>This is why phenological shifts have been observed worldwide, and contextually, it seems that phenological events are occuring earlier year by year. </p>
<p>Japan’s <em>Sakura</em> or cherry blossom season is one of the <a href="https://doi.org/10.1007/s00484-019-01719-9">most evident proofs</a> of this shift. Dating back to the ninth century, the date of flowering, which defines the festival’s timing, has been anticipated in the last century by the rise in average temperatures. </p>
<h2>What is the problem? Spring is cool, right?</h2>
<p>American poet <a href="https://www.goodreads.com/quotes/136895-if-we-had-no-winter-the-spring-would-not-be">Anne Bradstreet</a> said, “If we had no winter, the spring would not be so pleasant.” While this is hyperbolic, we still need to consider that the timings of flowers blooming, fruits ripening and other such phenological events result from a long-lasting adaptation of each species to its surrounding environment.</p>
<figure class="align-center ">
<img alt="A lone green plant in a barren land stretch with dried plants." src="https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458682/original/file-20220419-18-z0vdiu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Changes in the environment can have economic consequences as it affects the quantity and quality of agriculture and forestry products.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>The timing of phenological events are calibrated to ensure the perfect environmental condition needed to accomplish the annual cycles of a plant’s life while <a href="https://doi.org/10.1016/j.foreco.2020.118483">minimizing the risk of damage</a>. Changes in these conditions can have ecological as well as economic consequences as they can affect the quantity and quality of agriculture and forestry products. </p>
<p>At the end of the growing season, plants develop dormant buds to protect the sensitive <a href="https://www.britannica.com/science/meristem">meristematic cell layer</a> — tissue in which cells maintain the ability to divide throughout the life of the plant — and suspend activity. Dormancy is an adaptation mechanism evolved in climates with seasons to escape harsh winter conditions. </p>
<p>Warm spring temperatures (called forcing), the increase in day length during spring (photoperiod), and the length and intensity of winter temperatures (<a href="https://doi.org/10.1098/rstb.2011.0186">chilling</a>) reactivate the growth of the <a href="https://www.biologyonline.com/dictionary/apical-bud">apical buds</a> — the buds located at the top of the plant — in the spring. Clearly, temperature has a central and leading role in this process. For this reason, warming can trigger an <a href="https://doi.org/10.1093/treephys/tpaa096">earlier reactivation in spring</a> and a delayed cessation in autumn, or both, <a href="https://doi.org/10.1016/j.foreco.2019.01.005">lengthening the growing season</a>.</p>
<p>Some believe that a longer growing season could enhance carbon uptake and, therefore, the productivity of forests. In some places, such as regions in the northern latitudes or elevated altitudes, trees have profited from a <a href="https://doi.org/10.1016/j.foreco.2020.118483">longer growing season</a> and, more generally, more favourable climatic conditions under global warming. </p>
<figure class="align-center ">
<img alt="Snow and ice cover on a blooming cherry tree." src="https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458260/original/file-20220414-26-5wo0gn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Late frosts in spring and early frosts in autumn, that often accompany longer growing seasons, increase the risk for damage to plants and trees.</span>
<span class="attribution"><span class="source">(AP Photo/Carolyn Kaster)</span></span>
</figcaption>
</figure>
<p>However, an earlier growth reactivation increases the risk of damage due to <a href="https://doi.org/10.1016/j.foreco.2019.01.005">late spring frosts, and lengthening of the growing season increases the risk of damage by early autumn frosts</a>. </p>
<p>If trees cannot adapt, or re-adapt, their phenology with the new climatic conditions, the fitness and growth performance of local populations could be dramatically affected.</p>
<h2>If phenology changes, species interaction changes</h2>
<p>Ecosystems are generally complex and the species within them interact with each other as well as their surrounding environment. Different species can react differently to the changing climatic conditions, potentially leading to dangerous new phenological matches or mismatches. </p>
<p>For example, current climatic conditions create new phenological matches between prey and predators. <a href="https://doi.org/10.1111/gcb.14991">Black spruce may become a key host for the spruce budworm</a> given that the timing of maximum larvae activity could be better synchonized with the timing of yearly shoots development, which increases the risk of severe defoliations for one of the most profitable boreal species in North America. </p>
<p>Climate change can also cause mismatches between plants and their pollinators. Bumblebees represent one of the <a href="https://doi.org/10.1126/science.aaa7031">most important pollinators</a> for several wild species and many varieties of enormous agricultural interest. Bumblebees, given their low heat and cold tolerance, are particularly sensitive to environmental conditions. For this reason, the projected climatic risk for this species is <a href="https://doi.org/10.1126/science.aaa7031">extremely high</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A bumblebee sits on a wild flower." src="https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=516&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=516&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=516&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=648&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=648&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458284/original/file-20220414-14135-yes4wi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=648&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bumblebees are extremely sensitive to climate change.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>The mutually beneficial plant-pollinator relationship is an essential ecosystem service, specially considering that the pollination done by insects contributes to <a href="https://doi.org/10.1016/j.ecolecon.2008.06.014">9.5 per cent of global food production</a>.</p>
<h2>Action must be taken</h2>
<p>As the climate continues to change, affecting all kinds of ecosystems in the process, we need to be aware of plant phenology and think about how these shifts may directly affect our lives and businesses. </p>
<p>Scientists, today, use observational data to determine how species, populations and communities are vulnerable to these ongoing and projected future changes in climate. This research can be the foundation for essential human intervention, which may influence <a href="https://doi.org/10.1016/j.foreco.2019.01.005">plant distribution through assisted migration</a>, which is the human-assisted movement of species to areas far outside their established range. This will help tree species resynchronize their phenology to the current climatic condition. </p>
<p>Plant phenology is the result of an adaptation. However, adaptation requires time, an amount of time we do not have given the magnitude and rate at which we are observing climate changes. Constantly monitoring the phenological shifts worldwide will allow us to develop sound strategies to protect the most vulnerable ecosystems as well as our businesses. </p>
<p>Besides, we are like autumn leaves on branches, but at least we should try not to fall!</p><img src="https://counter.theconversation.com/content/181231/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roberto Silvestro received the Merit scholarship for international PhD students (PBEEE) assigned by the Fonds de Recherche du Québec - Nature et Technologies (FRQNT). </span></em></p><p class="fine-print"><em><span>Sergio Rossi receives funding from Natural Sciences and Engineering Research Council of Canada, Fonds de recherche du Québec - Nature et technologie, Ministère des Forêts, de la Faune et des Parcs du Québec</span></em></p>Climate change is modifying the timing of recurrent life-cycle events with critical consequences on ecological and economic levels.Roberto Silvestro, PhD candidate, biology, Université du Québec à Chicoutimi (UQAC)Sergio Rossi, Professor, Département des Sciences Fondamentales, Université du Québec à Chicoutimi (UQAC)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1803562022-04-14T13:53:34Z2022-04-14T13:53:34ZWhy birds migrate vast distances – and how you can help during their breeding season<figure><img src="https://images.theconversation.com/files/458128/original/file-20220414-15-d3i8yu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ospreys spend summer in the UK</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/osprey-flying-sky-2063210810">Vlad G/shutterstock</a></span></figcaption></figure><p>Now that spring is in the air, the UK is starting to see its summer visitors arriving. Ospreys are already back <a href="https://www.lrwt.org.uk/rutlandospreys">in their nests</a>, chiffchaffs are singing their song to <a href="https://www.jstor.org/stable/4535548?seq=1">re-establish their territories</a>, and puffins have arrived at their <a href="https://www.wildlifetrusts.org/where_to_see_puffins">breeding sites</a> around the British Isles.</p>
<p>Several centuries ago, people believed that swallows spent the winter asleep at the bottom of ponds and lakes, or <a href="https://www.historytoday.com/archive/natural-histories/great-migration-mystery">even on the Moon</a> - but of course, that was complete nonsense.</p>
<p>We now know that animals migrate to increase their survival – and that of their offspring. It also helps in their quest to find food, a mate or to avoid predators.</p>
<p>Although we tend to think of migration as birds flying from one country to another, there are actually <a href="https://www.nationalgeographic.org/article/natures-most-impressive-animal-migrations/">many animals who migrate</a>. Wildebeest, for example, undertake a <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/597229">circular migration</a>, roaming the African plains in huge numbers during the dry season in search of fresh grass. And <a href="http://repositorio.furg.br/handle/1/3452">humpback whales</a> migrate to warmer waters to raise their offspring.</p>
<p>However, it is birds who are the record breakers when it comes to travel. </p>
<p>The <a href="https://www.guinnessworldrecords.com/world-records/86385-longest-non-stop-migration-by-a-bird">bar-tailed godwit</a> has the longest recorded non-stop migration, with one individual spending almost ten days travelling from Alaska to New Zealand without a break – that’s a huge journey of around 12,200km (7,580 miles).</p>
<p>But the <a href="https://www.youtube.com/watch?v=bte7MCSBZvo">Arctic tern</a> is the true champion, making a round trip of 35,000km (22,000 miles) from the Arctic to the Antarctic and back again each year. This huge migration means that it lives in a constant summer – experiencing more daylight than any other animal – as it stops off in countries including Mauritania, Ghana and South Africa, during its <a href="https://www.researchgate.net/publication/339530181_Seasonally_specific_responses_to_wind_patterns_and_ocean_productivity_facilitate_the_longest_animal_migration_on_Earth/figures?lo=1">global trek</a>. </p>
<h2>How birds find their way</h2>
<p>Migration is a costly business – birds need to carry enough fat reserves to power their flight and sustain themselves over the duration of their journey. Getting lost could have disastrous consequences, so birds have developed incredible navigation skills to help them fly the shortest and safest routes.</p>
<p>Some species have an innate, inherited ability to migrate, which allows them to move to areas independently to enhance their survival. </p>
<p>The cuckoo, for example, is not raised by its parents as cuckoo mothers lay their eggs in nests belonging to birds of a completely different species. Yet, a young cuckoo is able to travel alone, from Europe to Africa, and back again, by using an inherited <a href="https://news.ku.dk/all_news/2020/06/cuckoo-chicks-have-an-innate-gps/#:%7E:text=By%20moving%20young%20cuckoos%201800,broader%20understanding%20of%20bird%20migration.">“internal GPS”</a>.</p>
<figure class="align-center ">
<img alt="Cuckoo sitting on a green bush" src="https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458137/original/file-20220414-13-l8etad.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cuckoos are part of a tracking programme using mini data loggers.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beautiful-cockoo-sitting-on-green-bush-1457541527">Urcan Uk/shutterstock</a></span>
</figcaption>
</figure>
<p>But some species, like the Caspian tern – which undertakes a long-distance migration from its breeding home in northern Europe to its wintering location in Africa – have very little inherited basis to their migratory habits. In most cases, they are taught by their parents, also known as “cultural inheritance” or social learning.</p>
<p>A recent study, for example, found that young Caspians seem to <a href="https://www.nature.com/articles/s41467-022-29300-w">learn their migratory route</a> from their father, who carries the main responsibility for migrating with their young birds. Along the journey, he also shows them suitable stopover sites for refuelling with fish and crustaceans.</p>
<p>But, whether inherited genetically or socially, birds <a href="https://www.nationalgeographic.org/media/how-do-birds-navigate/">use a variety</a> of natural cues, such as the shape of coastlines or the position of the Sun or stars –- or olfactory cues like the smell of their nest – to help them navigate their way around the globe.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/birds-use-massive-magnetic-maps-to-migrate-and-some-could-cover-the-whole-world-154992">Birds use massive magnetic maps to migrate – and some could cover the whole world</a>
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</em>
</p>
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<p>Some birds, such as homing pigeons, even <a href="https://www.nature.com/articles/news041122-7">use a magnetic map</a> to align themselves with the Earth’s magnetic field as they travel.</p>
<h2>UK’s summer visitors</h2>
<p>Our knowledge of bird migration has increased dramatically since the development of biologgers, tiny data-logging devices that are attached to the birds. These allow us to track an individual’s location, speed, stopover sites and the timing of their migration. </p>
<p>One such study is the <a href="https://www.bto.org/our-science/projects/cuckoo-tracking-project">cuckoo tracking project</a>. This has revealed that several cuckoos left central Africa around the start of 2022, each travelling separately for hundreds of kilometres before stopping for a couple of weeks in countries including the Ivory Coast and Morocco. They then continued with the next leg of their journey, and the most northerly bird had reached France around the 10 April. These migrating cuckoos are expected back to their breeding grounds in the UK very soon.</p>
<p>And they are not alone. Many birds undertake long distance migrations to the UK for the summer breeding season. For example, the <a href="https://www.rspb.org.uk/birds-and-wildlife/natures-home-magazine/birds-and-wildlife-articles/migration/migratory-bird-stories/wheatear-migration/">wheatear</a> also winters in Central Africa, but is back in the UK much earlier, from late February to mid August, whereas the <a href="https://hawkandowltrust.org/about-birds-of-prey/hobby">hobby</a> - a predator of dragonflies - winters in South Africa and is in the UK from late April to October. </p>
<figure class="align-center ">
<img alt="Housemartin sitting on her nest" src="https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458131/original/file-20220414-15-6tqkac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">There are numerous ways to help birds, such as these housemartins, when they are living on your shores.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/house-martin-delichon-urbica-single-adult-144672881">Erni/shutterstock</a></span>
</figcaption>
</figure>
<p>This enables them to take advantage of the longer hours of daylight and abundance of food, such as insects, during the UK’s summer months. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/garden-bird-feeders-are-boosting-blue-tit-numbers-but-leaving-other-species-hungry-161568">Garden bird feeders are boosting blue tit numbers – but leaving other species hungry</a>
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</em>
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<p>If you’d like to help birds over their breeding season – and at the same time help other, more permanent avian residents, such as tits and sparrows – here are a few ideas.</p>
<p>Feeding birds nuts, seeds and household scraps such as pastry, fruit or cheese, will help to <a href="https://www.rspb.org.uk/birds-and-wildlife/advice/how-you-can-help-birds/feeding-birds/">provide some easily accessible food</a>. </p>
<p>But some species, such as house martins and swallows, rely on insects. So, enhancing the biodiversity in your garden by <a href="https://www.rhs.org.uk/advice/how-to-grow-a-mini-wildflower-meadow">creating a wildflower meadow</a>, or taking part in <a href="https://www.plantlife.org.uk/uk/discover-wild-plants-nature/no-mow-may">no mow May</a> – an initiative from British conservation charity, Plantlife, asking everyone to “lock up their lawnmowers” and let vegetation grow during the month of May – will also be hugely beneficial. </p>
<p>Don’t forget that birds also need water, for drinking and bathing in, so a small bird bath or <a href="https://www.wildlifetrusts.org/actions/how-create-mini-pond">wildlife pond</a> is ideal. You can also <a href="https://www.bto.org/how-you-can-help/providing-birds/putting-nest-boxes-birds">put up nestboxes</a> to provide even more resources for our returning birds - an excellent substitute for the lack of natural nest sites for raising young, especially in urban areas. </p>
<p>Waking up to birdsong, courtesy of our summer visitors, including willow warblers and nightingales, brings joy to so many of us. Let’s not forget the epic journey they’ve taken to reach our shores - and do what we can to ensure a successful breeding season.</p><img src="https://counter.theconversation.com/content/180356/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Louise Gentle works for Nottingham Trent University</span></em></p>Birds are master navigators, negotiating journeys of thousands miles each year.Louise Gentle, Principal Lecturer in Wildlife Conservation, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1804842022-04-13T21:51:22Z2022-04-13T21:51:22ZSacred hares, banished winter witches and pagan worship – the roots of Easter Bunny traditions are ancient<figure><img src="https://images.theconversation.com/files/458017/original/file-20220413-15-x0e57b.jpg?ixlib=rb-1.1.0&rect=222%2C49%2C7959%2C5425&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Children celebrating Easter, with their Easter Bunnies and Easter eggs.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/two-young-boys-wearing-easter-bunny-ears-royalty-free-image/1388063471?adppopup=true">Sanja Radin/Collection E+ via Getty Images</a></span></figcaption></figure><p>The Easter Bunny is a much celebrated character in American Easter celebrations. On Easter Sunday, children look for hidden special treats, often chocolate Easter eggs, that the Easter Bunny might have left behind.</p>
<p>As a <a href="https://scholar.google.com/citations?user=prZyKrMAAAAJ&hl=en">folklorist</a>, I’m aware of the origins of the <a href="https://www.researchgate.net/publication/346357286_The_Shifting_Baselines_of_the_British_Hare_Goddess">long and interesting journey</a> this mythical figure has taken from European prehistory to today. </p>
<h2>Religious role of the hare</h2>
<p>Easter is a celebration of spring and new life. Eggs and flowers are rather obvious symbols of female fertility, but in European traditions, the bunny, with its amazing reproduction potential, is not far behind.</p>
<p>In European traditions, the Easter Bunny is known as the Easter Hare. The symbolism of the hare has had many tantalizing ritual and religious roles down through the years.</p>
<p>Hares were <a href="https://doi.org/10.1016/j.jasrep.2020.102672">given ritual burials</a> alongside humans during the Neolithic age in Europe. Archaeologists have interpreted this as a religious ritual, with hares representing <a href="https://www.exeter.ac.uk/news/research/title_787590_en.html">rebirth</a>. </p>
<p>Over a thousand years later, during the Iron Age, ritual burials for hares were common, and in 51 B.C., Julius Caesar mentions that in Britain, <a href="https://www.researchgate.net/publication/346357286_The_Shifting_Baselines_of_the_British_Hare_Goddess">hares were not eaten</a>, due to their religious significance.</p>
<p>Caesar would likely have known that in the Classical Greek tradition, <a href="https://www.theoi.com/Text/PhilostratusElder1A.html">hares were sacred to Aphrodite</a>, the goddess of love. Meanwhile, Aphrodite’s son Eros was often depicted carrying a hare, <a href="https://doi.org/10.1515/9783110308815.311">as a symbol of unquenchable desire</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A painting depicting a young woman handing baby Jesus to Virgin Mary, who puts one hand around him, while holding a hare with the other." src="https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=474&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=474&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=474&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=596&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=596&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458014/original/file-20220413-26-khhsks.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=596&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">‘The Madonna of the Rabbit,’ a painting from 1530, depicting the Virgin Mary with a hare.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/a/ab/Tizian_018.jpg">A painting by artist Titian (1490-1576), Louvre Museum, Paris.</a></span>
</figcaption>
</figure>
<p>From the Greek world through the Renaissance, hares often appear as symbols of sexuality in literature and art. For example, the Virgin Mary is often <a href="http://musee.louvre.fr/oal/viergeaulapinTitien/viergeaulapinTitien_acc_en.html">shown with a white hare or rabbit</a>, symbolizing that she overcame sexual temptation.</p>
<h2>Hare meat and witches’ mischief</h2>
<p>But it is in the folk traditions of England and Germany that the figure of the hare is specifically connected to Easter. Accounts from the 1600s in Germany describe children hunting for Easter eggs hidden by the Easter Hare, much as in the contemporary United States today. </p>
<p>Written accounts from England around the same time also mention the Easter Hare, particularly in terms of traditional Easter hare hunts, and the eating of hare meat at Easter. </p>
<p>One tradition, known as the “Hare Pie Scramble,” was held at Hallaton, a village in Leicestershire, England, which involved eating a pie made with hare meat and people “scrambling” for a slice. In 1790, the <a href="https://www.jstor.org/stable/1253567">local parson tried to stop the custom</a> due to its pagan associations, but he was unsuccessful, and the custom continues in that village until this day. </p>
<p>The eating of the hare may have been associated with various longstanding folk traditions of scaring away witches at Easter. Throughout Northern Europe, folk traditions record a strong belief that witches would often <a href="https://www.jstor.org/stable/1260796">take the form of the hare</a>, usually for causing mischief such as stealing milk from neighbors’ cows. Witches in medieval Europe were often believed to be able to suck out the life energy of others, making them ill, and suffer.</p>
<p>The idea that the witches of winter should be <a href="https://www.jstor.org/stable/24862791">banished at Easter</a> is a common European folk motif, appearing in several festivities and rituals. The spring equinox, with its promise of new life, was held symbolically in opposition to the life-draining activities of witches and winter.</p>
<p>This idea provides the underlying rationale behind various festivities and rituals, such as the “Osterfeuer,” or the Easter Fire, a celebration in Germany involving large outdoor bonfires <a href="https://www.twosmallpotatoes.com/osterfeuer-embracing-easter-traditions-in-germany/">meant to scare away witches</a>. In Sweden, the popular folklore states that at Easter, the witches all fly away on their broomsticks <a href="http://realscandinavia.com/in-sweden-easter-is-a-time-for-witches/">to feast and dance with the Devil</a> on the legendary island of Blåkulla, in the Baltic Sea. </p>
<h2>Pagan origins</h2>
<p>In 1835, the folklorist <a href="https://www.newworldencyclopedia.org/entry/Jacob_Grimm">Jacob Grimm</a>, one of the famous team of the fairy tale “Brothers Grimm,” argued that the Easter Hare <a href="https://doi.org/10.1080/00438243.2018.1515655">was connected with a goddess</a>, whom he imagined would have been called “Ostara” in ancient German. He derived this name from the Anglo-Saxon goddess Eostre, that <a href="https://exploringcelticciv.web.unc.edu/bede-the-history-of-the-english-church/">Bede</a>, an Anglo-Saxon monk considered to be the father of English history, mentioned in 731. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The goddess Ēostre/*Ostara flies through the heavens surrounded by winged angels, beams of light and animals." src="https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458019/original/file-20220413-26-jdne8p.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">‘Ostara’ by Johannes Gehrts, created in 1884. The goddess Ēostre flies through the heavens surrounded by Roman-inspired putti, beams of light, and animals.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/%C4%92ostre#/media/File:Ostara_by_Johannes_Gehrts.jpg">Felix Dahn, Therese Dahn, Therese (von Droste-Hülshoff) Dahn, Frau, Therese von Droste-Hülshoff Dahn (1901) via Wikimedia Commons.</a></span>
</figcaption>
</figure>
<p>Bede noted that in eighth-century England the month of April was called Eosturmonath, or Eostre Month, <a href="https://www.jstor.org/stable/1253567">named after the goddess Eostre</a>. He wrote that a pagan festival of spring in the name of the goddess had become assimilated into the Christian celebration of the resurrection of Christ.</p>
<p>It’s interesting that while most European languages refer to the Christian holiday with names that come from the Jewish holiday of Passover, such as Pâques in French, or Påsk in Swedish, German and English languages retain this older, non-biblical word, Easter.</p>
<p>Recent <a href="https://www.researchgate.net/publication/346357286_The_Shifting_Baselines_of_the_British_Hare_Goddess">archaeological research</a> appears to <a href="https://doi.org/10.2752/175169708X329372">confirm the worship of Eostre</a> in parts of England and in Germany, with the hare as her main symbol. The Easter Bunny therefore seems to recall these <a href="https://doi.org/10.1080/00438243.2018.1515655">pre-Christian celebrations of spring</a>, heralded by the vernal equinox and personified by the Goddess Eostre.</p>
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<p>After a long, cold, northern winter, it seems natural enough for people to celebrate themes of resurrection and rebirth. The flowers are blooming, birds are laying eggs, and baby bunnies are hopping about. </p>
<p>As new life emerges in spring, the Easter Bunny hops back once again, providing a longstanding cultural symbol to remind us of the cycles and stages of our own lives.</p><img src="https://counter.theconversation.com/content/180484/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tok Thompson does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A folklorist explains the prehistoric origins of the mythical Easter Bunny and why this longstanding cultural symbol keeps returning each spring.Tok Thompson, Professor of Anthropology and Communication, USC Dornsife College of Letters, Arts and SciencesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1678832021-10-04T19:06:35Z2021-10-04T19:06:35ZRosemary in roundabouts, lemons over the fence: how to go urban foraging safely, respectfully and cleverly<figure><img src="https://images.theconversation.com/files/424373/original/file-20211004-19-19r21tk.jpg?ixlib=rb-1.1.0&rect=46%2C26%2C4360%2C2853&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Does anything beat the experience of finding a wild mulberry tree and stuffing a handful of fresh juicy berries in your mouth? Have you ever roasted potatoes with a sprig of rosemary taken from an overgrown nature strip? </p>
<p>COVID lockdowns have encouraged more people to explore their neighbourhoods and appreciate <a href="https://theconversation.com/spending-time-in-nature-has-always-been-important-but-now-its-an-essential-part-of-coping-with-the-pandemic-153073">their local green spaces</a>, where edible plants are often growing freely. Alongside the joy in eating something freely harvested, foraging can help us learn about plants, become better environmental stewards, and bring together communities. </p>
<p>It can also help us notice changes in season, weather and climate. So with spring upon us, how do you forage safely, respectfully, and legally?</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Lmm51Cyf9_8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">12 Australian bushfoods.</span></figcaption>
</figure>
<h2>Wild, edible plants thrive in cities</h2>
<p>The locations of Sydney and Melbourne were chosen by colonists, in part, because they’re within large food basins. Many edible species existed well before colonisation, thanks to the favourable climate, shape of the coastline and custodianship of Country.</p>
<p>Edible native plants, from ground covering warrigal greens to the huge canopies of Illawarra plum trees, are still naturally growing all over southeast Australian cities. Further north, macadamias, lemon myrtles and finger limes thrive, and <a href="https://www.bhg.com.au/everything-about-pigface">pigface</a> is common on sand dunes along coastal towns.</p>
<p>Today, edible plants thrive despite the disturbances of soils and water from urbanisation. Fruit trees, for example, emerge spontaneously on the edges of park lands, in vacant lots and in people’s gardens.</p>
<p>In some cases, urbanisation is actually responsible for the growth and distribution of edible plants. </p>
<p>Birds, rats, bats broaden the trajectories of mulberry, loquat, and papaya seeds by eating them and expelling the seeds somewhere else. This is also how mulberries, which European settlers introduced to Australia, now grow in most Australian cities. </p>
<p>Kumquat, citrus, and fig trees are also very common in tropical and temperate climates. And keep an eye out for blackberry vines. They’ve created an immense environmental problem, although the fruit is delicious, and grow best in NSW, Victoria and Tasmania. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424395/original/file-20211004-13-jkwhj5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Not everyone likes it when you pick from their nature strip.</span>
<span class="attribution"><span class="source">Courtesy of Mapping Edges</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Think before you pick</h2>
<p>But foraging is not a free for all, and doing it safely and respectfully is important. </p>
<p>First and foremost, in Australia, wherever you walk, you are on Country. Take a moment to remember that although urban foraging may be new to you, Aboriginal people have always gathered native plants while caring for Country.</p>
<p>Foraging also carries possible risks to your own health. Some plants in urban areas are poisonous, such as the castor oil plant and many gum trees. Plants could also be contaminated from pollution in the air, water and soil, and by chemical sprays. </p>
<p>You can learn about some of the possible environmental contaminants in your neighbourhood <a href="https://www.mapmyenvironment.com/">here</a>, and there are a few services like <a href="https://www.360dustanalysis.com/">VegeSafe</a> that test soil samples for metals. </p>
<p>Always start by considering the past and current uses of the land where you’re foraging. Was the land once industrially zoned? Do dogs urinate there? Make sure you always wash foraged food.</p>
<p>Legally, plants are the property of whoever owns the land on which they’re growing. That means foraging for food on private land is legal, as long as you either own the land or have the owner’s permission. </p>
<p>But if food is accessible on public land — such as lemons or bananas hanging over a fence, or rosemary and parsley planted as ornamentals in a park or street shoulder — you can harvest them. Just take what you need, and leave plenty for others.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/our-land-abounds-in-nature-strips-surely-we-can-do-more-than-mow-a-third-of-urban-green-space-124781">Our land abounds in nature strips – surely we can do more than mow a third of urban green space</a>
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</em>
</p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424394/original/file-20211004-23-1whq400.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Make sure you wash foraged plants before you eat them.</span>
<span class="attribution"><span class="source">Courtesy of Mapping Edges</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Foraging respectfully</h2>
<p>There are different cultures around growing and sharing food, depending on the local area. For example, many neighbourhood nature strips are technically owned by the council, but planted and tended by residents. </p>
<p>Community gardens and even streets with nature strips may have their own harvesting rules. Some groups like <a href="https://www.cityofsydney.nsw.gov.au/community-gardens/green-square-growers">Green Square Growers</a> encourage spontaneous harvesting. Others, such as <a href="https://www.cityofsydney.nsw.gov.au/community-gardens/sydney-city-farm">Sydney City Farm</a>, donate produce to local charities.</p>
<p>Since 2016, we have been working in various suburbs of Sydney to <a href="https://www.mappingedges.org/projects/home-gardens-of-haberfield/">conduct research</a> on urban gardening. We discovered people often work with plants to develop a sense of place that goes well beyond what’s visible in their gardens. </p>
<p>We found networks of neighbours grow together with plants on street edges, through exchanging cuttings, seeds, tips, stories and produce. Coming across a row of trees heavy with olives on a nature strip may feel like a lucky discovery, but these plants are probably watered, pruned, and whitewashed for winter by one or more gardeners. </p>
<p>For someone who has carefully netted a fruit tree to protect it from bats and cockatoos, or who has patiently tended a vine for three years before their first passionfruit appears, there’s nothing more infuriating than a stranger harvesting. </p>
<p>On the other hand, helping yourself to a fragrant feijoa tree weighed down by ripe fruit makes sense, when the fruits would otherwise fall, rot and go to waste. </p>
<p>When possible, ask residents about the plants growing on or around their properties. Conversations about what’s growing in neighbourhoods build so-called “<a href="https://www.mappingedges.org/projects/the-green-square-atlas-of-civic-ecologies/what-are-civic-ecologies/">civic ecologies</a>” — actions that bring together environmental and civic values, building neighbourly connections around common interests and care for shared places.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/supermarket-shelves-stripped-bare-history-can-teach-us-to-make-do-with-food-135304">Supermarket shelves stripped bare? History can teach us to 'make do' with food</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=802&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=802&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=802&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1008&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1008&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424377/original/file-20211004-13-1xgj4rn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1008&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Foraging on nature strips can depend on local council rules.</span>
<span class="attribution"><span class="source">Courtesy of Mapping Edges</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Learn from foraging celebrities</h2>
<p>In Australia, a hand full of “foraging” celebrities have brought attention to this age old practice. They see foraging as an opportunity to learn about what’s growing where, and why. </p>
<p>In Sydney, Randwick Council Sustainability Educator Julian Lee, has created a Scrumper’s Delight <a href="https://www.google.com/maps/d/edit?mid=1z4E4KYaDZLVFs-ShpcF-WgYglHg&ie=UTF8&oe=UTF8&msa=0&ll=-33.91414914832107%2C151.20033552888276&z=21">participatory map</a> that records edible plants growing in public spaces. Sydney artist and activist Diego Bonetto — aka <a href="https://www.diegobonetto.com/about">The Weedy One</a> — brought a wealth of planty knowledge from Piedmont, Italy to Australia in the 1990s, and since then his passion has evolved to a public pedagogy about respectful foraging.</p>
<p><a href="https://www.milkwood.net/2018/11/06/the-right-to-roam-tips-for-first-time-foragers/">Milkwood Permaculture</a> offer tips, even on foraging sea weed. The <a href="https://www.instagram.com/melbourneforager/?hl=en">Melbourne Forager</a> on Instagram makes urban foraging hip. And a growing number of Indigenous businesses, such as <a href="https://www.indigigrow.com.au/">Indigigrow</a>, share Indigenous knowledge by selling plants people can recognise outside their gardens. </p>
<p>Foraging in cities is fun, it helps us remember we’re part of ecosystems, and we have a responsibility to care for Country. So keep in mind principles of reciprocity, and go forth and learn what’s growing in your city. </p>
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<strong>
Read more:
<a href="https://theconversation.com/farming-the-suburbs-why-cant-we-grow-food-wherever-we-want-80330">Farming the suburbs – why can’t we grow food wherever we want?</a>
</strong>
</em>
</p>
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<p><em>Correction: A previous version of this article said Sydney City Farm allocates produce to volunteers. In fact, the produce is donated to local charities.</em></p><img src="https://counter.theconversation.com/content/167883/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Spring has settled in and fruit is starting to ripen. Read this before you start helping yourself to the edible plants growing in your neighbourhood.Alexandra Crosby, Associate Professor, School of Design, University of Technology SydneyIlaria Vanni, Associate Professor, International Studies and Global Societies, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1680892021-09-23T20:04:15Z2021-09-23T20:04:15ZThe sun’s shining and snakes are emerging, but they’re not out to get you. Here’s what they’re really up to<figure><img src="https://images.theconversation.com/files/422809/original/file-20210923-15-yxnhp7.jpg?ixlib=rb-1.1.0&rect=0%2C14%2C4914%2C3057&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>It’s early spring in southern Australia and the sun is, gloriously, out. You decide to head to your local patch of greenery – by the creek, lake, or foreshore – with the sun on your face, the breeze in your hair, and your dog’s tongue blissfully lolling. </p>
<p>Suddenly you see it. Paused on the path just a few meters in front of your feet, soaking up those same springtime rays — a snake.</p>
<p>Love them or loathe them, snakes have been co-existing with, and haunting us, since well before our ancestors called themselves “human”. From the <a href="https://www.biblegateway.com/verse/en/Genesis%203%3A1">subtle tempter of Genesis</a> to the <a href="https://www.worldhistory.org/Quetzalcoatl/">feathered serpent deities of Mesoamerica</a>, snakes have always been potent symbols of otherness. </p>
<p>Today, to encounter a snake is to brush up against the wild and mysterious heart of the natural world. Snakes are important members of every terrestrial ecosystem across Australia. Even in the most populous parts of the country, snakes inhabit the remnant bushland dispersed throughout our major cities. </p>
<p>But what exactly influences human–snake interactions? Whether you’re hoping to maximise your chances of seeing one of these shy, fascinating critters or wanting to avoid them at all costs, this article is for you.</p>
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<h2>Snakes in southern springtime</h2>
<p>In southern Australia, a flurry of animal activity occurs in spring. As resources start becoming plentiful after the relatively lean months of winter, spring is the reproductive season for many plants and animals. </p>
<p>One such resource is heat — a particularly crucial resource for organisms such as reptiles, which don’t make their own body heat (unlike mammals). It’s a common misconception, however, that snakes want as much heat as they can get. Like Goldilocks, snakes want the temperature to be just right. </p>
<p>Southern springs are the right temperature for snakes to bask during the times of day we humans are also out and about. In summer, snakes, including venomous species such as tiger snakes and brown snakes, are typically more active very early in the morning, late in the evening, or during the night when temperatures are not too high for them.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422824/original/file-20210923-15-13vcmkp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">During spring in south-eastern Australia, red-bellied blacksnakes are common in suburban areas.</span>
<span class="attribution"><span class="source">Damian Lettoof</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>After a slow winter, snakes are both hungry (they may have been fasting for months!) and on the lookout for eligible members of the opposite sex. Basking, hunting, and searching for a mate brings snakes out into the open in spring a bit more than at other times of year, so we’re most likely to encounter them during this time.</p>
<h2>Snake activity in northern Australia</h2>
<p>Like all things, snake activity is a little different in the north. Spare a thought for those poor northern Australians who will never know the joys of a snake-filled springtime. </p>
<p>Still, the north has far more snake species than the south, including many species of non-venomous python — the farther south you go, the more our snake fauna is dominated by venomous species (check out <a href="http://www.arod.com.au/arod/">Australian Reptile Online Database</a> for distribution maps).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422836/original/file-20210923-22-e8ozjv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Darwin carpet pythons (<em>Morelia spilota variegata</em>) are most often encountered in the cooler months of the year following the annual wet season.</span>
<span class="attribution"><span class="source">Chris Jolly</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Because of the unforgiving year-round heat across northern Australia, temperature doesn’t drive snake activity as it does in the south. You will rarely see a basking snake in Australia’s Top End, they’re too busy avoiding the heat.</p>
<p>Instead, snake activity is driven by another important resource – rain. In the Top End, this means <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/aec.12990">snakes are most often encountered following the wet season</a> (April–June) when prey and water abound. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1245508878357262338"}"></div></p>
<p>In other, more arid “boom and bust” systems, large rainfall events may only happen every five to ten years. When they do, they can trigger huge flurries of snake activity as the serpents emerge to take advantage of fleetingly available prey.</p>
<h2>Snakes indicate ecosystem health</h2>
<p>From the moment of birth, all species of snake are predatory, although some, like <a href="http://www.arod.com.au/arod/reptilia/Squamata/Elapidae/Brachyurophis">shovel-nosed snakes</a>, prey only upon eggs. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422822/original/file-20210923-15-1u7uqly.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Shovel-nosed snakes prey only on eggs.</span>
<span class="attribution"><span class="source">Damian Lettoof</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In some terrestrial Australian ecosystems, snakes are near the top of the food chain. After reaching a certain size, they have few predators of their own. A two-metre coastal taipan in the cane fields of northern Queensland, for example, has more to fear from harvesters than it does from any natural predator. </p>
<p>For large snakes to persist in an environment, they need an abundance of their prey (mice, frogs and lizards), as well as all the species their prey feed upon (invertebrates, even smaller animals, or plants).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422838/original/file-20210923-17-14dxlnj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Coastal taipans (<em>Oxyuranus scutellatus</em>) are exceptionally elusive, but when they are (rarely) encountered, it is most often males observed while they are on the hunt for females during northern Australia’s winter.</span>
<span class="attribution"><span class="source">Chris Jolly</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Snakes often also have specific habitat requirements. In general, they need shelter and protection from bigger predators, which might include birds of prey, predatory mammals such as native marsupials or introduced cats and foxes, or other snakes. They also need opportunities for safely regulating their body temperature. </p>
<p>This means a snake will only call a place home if it has both a functioning food-web and the necessary habitat complexity. So remember, if you see snakes in your backyard or local park, it’s a sign the ecosystem is doing pretty well.</p>
<h2>Snakes don’t want to bite you</h2>
<p>Snakes are awesome predators, but no Australian snake is interested in eating a human. In fact, they want as little to do with us giant hairless apes as possible.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=384&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=384&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=384&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=482&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=482&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422813/original/file-20210923-22-1018xx6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=482&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Merri Creek in inner-city Melbourne is famously home to many snakes, including tiger snakes, who bask in the sun at springtime.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Why? Because snakes are actually quite vulnerable animals. Compared to many other species, they are small, have no sharp claws or strong limbs, and limited energy to put up a fight — they are basically limbless lizards with different teeth. </p>
<p>For those that possess it, venom is a last resort and only a minority of species —such as taipans, brown snakes, tiger snakes, and death adders — can deliver a life-threatening bite to a person. But snakes would much rather use their venom to subdue prey (that’s what they have it for) than to defend themselves.</p>
<p>When snakes bite humans in Australia, it’s a defensive reaction to a large animal they view as a potential predator. Remember, they can’t understand your intentions, even if those intentions are good. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=378&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=378&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=378&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=475&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=475&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422823/original/file-20210923-23-1dae3xb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=475&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tiger snakes and other venomous snakes won’t bite you if you respect their boundaries.</span>
<span class="attribution"><span class="source">Damian Lettoof</span></span>
</figcaption>
</figure>
<p>If you’re lucky enough to see a wild snake, and if you respect its boundaries and give it personal space, it’s sure to do the same for you. Keep dogs on the lead in snakey areas and educate your kids to be snake-smart from as young as possible. </p>
<p>Even though snakes don’t want to bite, snakebite envenoming can be a life-threatening emergency. Learn <a href="https://biomedicalsciences.unimelb.edu.au/departments/department-of-biochemistry-and-pharmacology/engage/avru/advice-and-resources/first-aid">first aid</a>, and when you go for a walk in one of those sanctuaries of greenery that snakes like as much as we do, carry a compression bandage (or three). </p>
<p>It’s almost certain you will never need it, but it could just save a life.</p>
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<strong>
Read more:
<a href="https://theconversation.com/does-australia-really-have-the-deadliest-snakes-we-debunk-6-common-myths-145765">Does Australia really have the deadliest snakes? We debunk 6 common myths</a>
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<img src="https://counter.theconversation.com/content/168089/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Timothy N. W. Jackson receives funding from the National Health and Medical Research Council. </span></em></p><p class="fine-print"><em><span>Chris J Jolly receives funding from National Environmental Science Program (Threatened Species Hub).</span></em></p><p class="fine-print"><em><span>Damian Lettoof receives funding from HWRE. </span></em></p>Whether you’re hoping to maximise your chances of seeing one of these shy, fascinating critters or wanting to avoid them at all costs, this article is for you.Timothy N. W. Jackson, Postdoctoral Research Fellow, Australian Venom Research Unit, The University of MelbourneChris J Jolly, Postdoctoral Research Fellow, Charles Sturt UniversityDamian Lettoof, PhD Candidate, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1673742021-09-10T03:21:42Z2021-09-10T03:21:42ZThe daily dance of flowers tracking the sun is more fascinating than most of us realise<figure><img src="https://images.theconversation.com/files/420390/original/file-20210910-21-16krrwb.jpg?ixlib=rb-1.1.0&rect=18%2C6%2C4174%2C2785&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Julien Christ/Unsplash</span></span></figcaption></figure><p>When I was a child, I was intrigued by <a href="https://www.anbg.gov.au/cpbr/cd-keys/RFK7/key/RFK7/Media/Html/entities/Lophostemon_confertus.htm">the Queensland box</a> (<em>Lophostemon confertus</em>) growing in our backyard. I noticed its leaves hung vertical after lunch in summer, and were more or less horizontal by the next morning. </p>
<p>This an example of heliotropism, which literally means moving in relation to the sun. We can see it most clearly as spring arrives and various species burst into flower — you might even get the feeling that some flowers are watching you as they move.</p>
<p>Many of us probably first got to know of heliotropism at home, kindergarten or primary school by watching the enormous yellow and black flowering heads of aptly name sunflowers, which moved as they grew. </p>
<p>These flowers track the course of the sun spectacularly on warm and sunny, spring or summer days. Sometimes they move through an arc of almost 180⁰ from morning to evening. </p>
<p>So with the return of sunny days and flowers in full bloom this season, let’s look at why this phenomenon is so interesting. </p>
<h2>The mechanics of tracking the sun</h2>
<p>A number <a href="https://echelonflorist.com/flower-talk/lessons-flowers-facing-sun-phototropic-plants/">flowering species</a> display heliotropism, including alpine buttercups, arctic poppies, alfalfa, soybean and many of the daisy-type species. So why do they do it?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420395/original/file-20210910-27-1px5oh7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This is <em>Heliotropium arborescens</em>, named for its heliotropism. They were very popular in gardens a century or more ago, but have fallen from favour as they can be poisonous and weedy.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Flowers are really in the advertising game and will do anything they can to attract a suitable pollinator, as effectively and as efficiently as they can. There are several <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/heliotropism">possible reasons</a> why tracking the sun might have evolved to achieve more successful pollination. </p>
<p>By tracking the sun, flowers absorb more solar radiation and so <a href="http://lifeofplant.blogspot.com/2011/03/heliotropism.html">remain warmer</a>. The warmer temperature suits or even rewards insect pollinators that are more active when they have a higher body temperature. </p>
<p>Optimum flower warmth may also boost pollen development and germination, leading to a higher fertilisation rate and more seeds. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-theres-a-lot-more-to-love-about-jacarandas-than-just-their-purple-flowers-150851">Why there's a lot more to love about jacarandas than just their purple flowers</a>
</strong>
</em>
</p>
<hr>
<p>So, the flowers are clearly moving. But how? </p>
<p>For many heliotropic flowering species, there’s a special layer of cells called the pulvinus <a href="https://depts.washington.edu/cims/research/Bio-Intelligent-Materials.pdf">just under the flower heads</a>. These cells pump water across their cell membranes in a controlled way, so that cells can be fully pumped up like a balloon or become empty and flaccid. Changes in these cells allow the flower head to move.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Venus fly trap" src="https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420399/original/file-20210910-13-yn5t11.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fly traps have somewhat similar mechanics to heliotropism.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>When potassium from neighbouring plant cells is moved into the cells of the pulvinus, water follows and the cells inflate. When they move potassium out of the cells, they become flaccid. </p>
<p>These potassium pumps are involved in many other aspects of plant movement, too. This includes the opening and closing of stomata (tiny regulated leaf apertures), the rapid movement of mimosa leaves, or the closing of a fly trap. </p>
<h2>But sunflowers dance differently</h2>
<p>In 2016, <a href="https://www.npr.org/sections/thetwo-way/2016/08/05/488891151/the-mystery-of-why-sunflowers-turn-to-follow-the-sun-solved">scientists discovered</a> that the pin-up example of heliotropism — the sunflower — had a different way of moving. </p>
<p>They found sunflower movement is due to significantly different growth rates on opposite sides of the flowering stem. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A sunflower facing a setting sun" src="https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420389/original/file-20210910-15-1q475ls.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Sunflowers move differently to other heliotropic flowers.</span>
<span class="attribution"><span class="source">Aaron Burden/Unsplash</span></span>
</figcaption>
</figure>
<p>On the east-facing side, the cells grow and elongate quickly during the day, which slowly pushes the flower to face west as the daylight hours go by — following the sun. At night the west-side cells grow and elongate more rapidly, which pushes the flower back toward the east over night. </p>
<p>Everything is then set for the whole process to begin again at dawn next day, which is repeated daily until the flower stops growing and movement ceases. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-secret-life-of-puddles-their-value-to-nature-is-subtle-but-hugely-important-154561">The secret life of puddles: their value to nature is subtle, but hugely important</a>
</strong>
</em>
</p>
<hr>
<p>While many people are aware of heliotropism in flowers, heliotropic movement of leaves is less commonly noticed or known. Plants with heliotropic flowers don’t necessarily have heliotropic leaves, and vice versa. </p>
<p>Heliotropism evolves in response to highly specific environmental conditions, and factors <a href="https://www.scienceabc.com/nature/sunflowers-always-face-follow-sun.html">affecting flowers</a> can be different from those impacting leaves. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420401/original/file-20210910-25-2xp1vf.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The leaves of Queensland box, <em>Lophostemon confertus</em>, which track the sun.</span>
<span class="attribution"><span class="source">Krzysztof Ziarnek, Kenraiz/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>For example, flowers are all about pollination and seed production. For leaves, it’s for maximising photosynthesis, avoiding over-heating on a hot day or even reducing water loss in harsh and arid conditions.</p>
<p>Some species, such as the Queensland box, arrange their leaves so they’re somewhat horizontal in the morning, capturing the full value of the available sunlight. But there are also instances where leaves align vertically to the sun in the middle of the day to minimise the risks of heat damage.</p>
<h2>Plants are dynamic</h2>
<p>It’s easy to think of plants as static organisms. But of course, they are forever changing, responding to their environments and growing. They are dynamic in their own way, and we tend to assume that when they do change, it will be at a very slow and steady pace.</p>
<p>Heliotropism shows us this is not necessarily the case. Plants changing daily can be a little unsettling in that we sense a change but may not be aware of what is causing our unease. </p>
<p>As for me, I still keep a watchful eye on those Queensland boxes!</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/it-is-risen-the-story-of-resurrection-ferns-and-my-late-colleague-who-helped-discover-them-in-australia-157775">It is risen: the story of resurrection ferns and my late colleague who helped discover them in Australia</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/167374/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gregory Moore does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The phenomenon is called heliotropism, and sunflowers are most famous for it. But why do they track the sun? And how?Gregory Moore, Doctor of Botany, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1570362021-04-21T17:23:04Z2021-04-21T17:23:04ZSeedkeeping can connect people with their roots and preserve crops for future generations<figure><img src="https://images.theconversation.com/files/394338/original/file-20210409-23-cu50aj.jpg?ixlib=rb-1.1.0&rect=10%2C0%2C6699%2C4466&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cultivating traditional plants is a way of creating a space that is familiar within a new and often alienating environment. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>“All seeds are sacred, these seeds are connected to 10,000 years of human relationship to the land,” says Owen Taylor, co-founder of Philadelphia-based <a href="https://trueloveseeds.com/">Truelove Seeds</a>, who sells vegetable, herb and flower seeds that tell ancestral and regional stories. He adds, “seedkeeping refers to not just the saving of seeds, but also the keeping of seed stories, cultural information, traditions, recipes, rituals and so on.” </p>
<p>Taylor says many of the varieties in Truelove’s seed catalogue are seeds that farmers and gardeners have collected from others, through seed exchanges and family lineages. “Most of our growers are on their own search for their beloved varieties — and to provide an outlet for some of the crops from home,” he says. Seeds from Syria to the African diaspora, those that tell the story of Philadelphia’s history and a wide variety of other culturally important seeds are included in the catalogue. </p>
<p>Taylor started Truelove Seeds in 2017, after managing a private heirloom seed collection with over 4,000 varieties. He co-founded the company with Chris Bolden-Newsome as a way to collaborate with farmers in the food sovereignty movement. Their goal was to preserve and make available culturally important seeds while providing mentorship for farmers, an outlet for their seeds and an income stream. </p>
<p>Truelove Seeds uses a profit-sharing model so gardeners and farmers make 50 per cent of every packet sale. Taylor and Bolden-Newsome also host a radio show called “<a href="https://trueloveseeds.com/blogs/satpradio">Seeds and Their People</a>,” which explores stories of seeds and community. </p>
<p>Practices of seedkeeping vary, and each seedkeeper offers their own story and connection to the seeds. Their efforts can create a sense of home, reconnect communities with ancestral crops and preserve biodiversity and culturally significant crops for future generations. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/indigenous-song-keepers-reveal-traditional-ecological-knowledge-in-music-123573">Indigenous song keepers reveal traditional ecological knowledge in music</a>
</strong>
</em>
</p>
<hr>
<h2>Seedkeeping and creating a familiar space</h2>
<p>“You don’t know how many days you will live in the jungle, so you have to carry the seeds, you carry the seeds for planting and medicine,” says Naw Ta Blu Moo, an interpreter for the Karen refugee community, an Indigenous community from Myanmar, at <a href="https://novickbrothers.com/urban-farm.html">Novick Urban Farm</a> in Philadelphia. </p>
<p>The Karen grow crops such as chilis, cucumber, gourd, bitter melon and the sour <a href="https://trueloveseeds.com/products/chin-baung-burmese-roselle-leaf?_pos=1&_sid=646890fb3&_ss=r">leaf of the roselle plant known as <em>chin baung ywet</em></a>. All sourced from an informal network of seedkeepers and savers from Myanmar, who bring seeds with them to North America, or preserve them and share them within the Karen community in the United States. “The farmers want to do more, and plant more because it helps heal their community,” says Blu Moo. </p>
<figure class="align-center ">
<img alt="Sour leaf or chin baung ywet" src="https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394334/original/file-20210409-13-9om14p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Karen grow crops such as chilis, cucumber, gourd, bitter melon, and sour leaf known as chin baung ywet from seeds sourced from an informal network of seedkeepers.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Shwe Chit, who fled his village with his family and resettled in Philadelphia because of ongoing conflict in Myanmar’s Kayin State, has spent five years working at Novick Urban Farm, where Karen gardeners can farm plots of land. He says the first year of land preparation was a challenge, but the reward of growing crops is worth it. He now sells his crops, such as winter gourd and hot pepper, at the Novick Urban Farmstand in the summer. </p>
<p>Blu Moo says for the Karen gardeners, finding exact seeds for the community can be difficult. Sometimes, community members thought they had secured the right seed but were wrong — as was the case with chilies; when the fruit came up, it was a Spanish chili, not one from Myanmar.</p>
<p>Terese Gagnon has worked with Karen gardeners for more than a decade, and is the co-editor of the upcoming book <a href="https://uapress.arizona.edu/book/moveable-gardens"><em>Moveable Gardens, Itineraries and Sanctuaries of Memory</em></a>.</p>
<p>She says cultivating plants from home is a way of creating a space that is familiar within a new and often alienating environment. “This includes having access to longed-for flavours, engaging in the physical work of gardening and getting to shape the landscape to have something that visually looks like home.”</p>
<h2>Co-operation and seedkeeping</h2>
<p>In the Arctic town of Svalbard, Norway, an initiative critical to food security and seedkeeping enables seeds to be deposited for future generations. </p>
<p>The <a href="https://www.croptrust.org/our-work/svalbard-global-seed-vault/">Svalbard Global Seed Vault</a> is a seed storage facility housed in a mountain, where copies of seeds from around the world are kept to prevent both incremental and catastrophic loss of crop diversity. According to the <a href="https://www.croptrust.org/">Crop Trust</a>, there are currently over one million seed samples in the vault, from nearly every country in the world. </p>
<p>Nations can deposit seeds from their <a href="https://www.croptrust.org/our-mission/crop-diversity-why-it-matters/need-genebanks/">genebanks</a> to <a href="https://www.croptrust.org/blog/an-international-rescue-mission-from-syria-to-svalbard/">safeguard them from human conflict or natural disaster</a>. Åsmund Asdal, the Svalbard Global Seed Vault co-ordinator, says that while nations may not be best friends, they co-operate in this important task to protect and preserve their seeds. </p>
<p>“Today, there are seeds from Russia and Ukraine on the same shelf. There are seeds from North Korea and South Korea. Even if countries are quite hostile to each other, they co-operate on this task to take care of the seeds.” The North Korean seeds are in seven wooden boxes made in North Korea, which contain seeds for cabbage, beans, barely and buckwheat, says Asdal. </p>
<figure class="align-center ">
<img alt="building with mountain in the back" src="https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&rect=12%2C0%2C4131%2C2490&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=360&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=360&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=360&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=452&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=452&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394337/original/file-20210409-23-1gebthd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=452&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Svalbard Global Seed Vault is a secure seed bank on the Norwegian island of Spitsbergen in the remote Arctic.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Reuniting seeds and community</h2>
<p>Tiffany Traverse of Peace River, B.C., is sowing seeds of <em>qwléwe</em>, or nodding onion, and other Indigenous crops. She says nodding onion is often destroyed by urban sprawl and tourists trying to access trails to the river. She is carefully transplanting the <em>qwléwe</em> to safer places so they can once again thrive. </p>
<p>Traverse, originally from Secwepemcúlecw territory, was mentored by one of the leaders of the seedkeeping movement, <a href="https://www.nativeseedpod.org/podcast/2018/episode-1-the-natural-law-of-seeds">Mohawk seedkeeper Rowen White</a>. </p>
<p>She founded <a href="https://www.facebook.com/4thsisterfarm/">Fourth Sister Farm</a>, where she works to provide access to healthy and culturally relevant seeds and foods, and uses traditional growing practices such as <a href="https://www.almanac.com/content/planting-by-the-moon">moon-phase planting</a>.</p>
<p>“What I’m doing is I’m stewarding those seeds to be returned back to the nations or the people or the communities they are linked to,” says Traverse. She’s referring to crops such as beans, tomatoes and squash, which she grows and returns to their respective communities — which can include sharing, teaching about seed saving, growing and recipes. </p>
<p>This process can also be referred to as rematriation. “Rematriation,” says Traverse, “is to return the seed ancestors home to their peoples and communities.” She believes by keeping and sowing seeds she is asking: “How are we going to help each other out? How will we lift each other up and grow these seeds out and share them back into the community?” </p>
<p>Gagnon says much of the work is about having to make spaces of sanctuary within a time of precarity. “Seeds weigh nothing and are designed to travel great distances,” says Gagnon. “Seeds are important companions with which people make home and create a sense of continuity, a cohesion to life, even when forced to be on the move or perpetually in-between.”</p><img src="https://counter.theconversation.com/content/157036/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Natalie Jesionka does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Seedkeeping can create a sense of home, reconnect communities with ancestral crops and preserve biodiversity and culturally significant crops for future generations.Natalie Jesionka, Dalla Lana Global Journalism Fellow, University of TorontoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1553432021-03-04T13:32:21Z2021-03-04T13:32:21ZJanuary warm spells, March freezes: How plants manage the shift from winter to spring<figure><img src="https://images.theconversation.com/files/387325/original/file-20210302-23-sgg0ra.jpg?ixlib=rb-1.1.0&rect=0%2C7%2C2640%2C1968&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A late snowfall could set back the growth of this budding lilac.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/9GHtrJ">oddharmonic/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Weather patterns across the U.S. have felt like a roller coaster ride for the past several months. December and January were <a href="https://www.ncdc.noaa.gov/sotc/national/202012">significantly warmer than average</a> in many locations, followed by February’s <a href="https://www.nytimes.com/2021/02/13/us/winter-storm-snow-ice.html">intense cold wave</a> and a <a href="https://www.washingtonpost.com/weather/2021/02/26/temperature-swing-central-united-states/">dramatic warmup</a>.</p>
<p>If you’ve ever seen lilac bushes crushed by snowdrifts, then budding on a warm day just a few weeks later, you may wonder how plants tolerate such extremes. I study <a href="https://scholar.google.com/citations?user=XfgB_BUAAAAJ&hl=en">how climate change affects the timing of seasonal events</a> in the life cycles of plants, birds and insects in Massachusetts, so I know that species have evolved here to handle New England’s famously changeable weather. But a warming climate is disrupting weather patterns and testing the abilities of many species to adapt.</p>
<h2>Tolerating cold</h2>
<p>On brutal winter days when temperatures are far below freezing, <a href="https://theconversation.com/is-winter-miserable-for-wildlife-108734">animals hibernate underground or huddle in protected spots</a>. But trees and shrubs have to sit there and take it. The tissues in their trunks, branches and roots are alive. How do they survive the freezing cold?</p>
<p>In autumn, woody plants in many parts of North America start <a href="https://doi.org/10.1016/j.tree.2015.01.004">preparing for winter</a>. When their leaves change color and fall, their twigs, branches and trunks start to lose water. As a result, their cells contain higher concentrations of sugars, salts and organic compounds. </p>
<p>This lowers the freezing point of the cells and tissues, and allows them to survive temperatures far below the normal freezing point of water. The trick has its limits, though, so extreme cold events can still kill certain plants.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Snow-coated tree branches against sunset sky." src="https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=747&fit=crop&dpr=1 600w, https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=747&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=747&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=939&fit=crop&dpr=1 754w, https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=939&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/387307/original/file-20210302-23-1r8c64h.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=939&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Trees in cold climates have evolved protections against ice and snow.</span>
<span class="attribution"><span class="source">Richard Primack</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Tree and shrub roots remain largely unchanged and inactive during winter, relying on insulation from snow and soil for protection. For the most part, the temperature of the soil around roots stays at or above freezing. Soil, fallen leaves and persistent snow layers insulate the ground above the roots and prevent it from losing heat.</p>
<h2>The surprising danger of spring frosts</h2>
<p>After plants stoically withstand cold winters, early spring brings new dangers. Plants need to leaf out as early as they can in spring to take full advantage of the growing season. But this involves pumping water into their developing leaves, which reduces the concentration of sugars, salts and organic compounds in their tissues and removes their winter protection from cold. </p>
<p>Each species has a <a href="https://doi.org/10.1111/nph.12892">characteristic leaf-out time</a>. Early-leafing species such as blueberries and willows are the gamblers of the plant kingdom. Later species, like oak and pine, are the cautious and conservative types. For any species, leafing out too early is a risk because late frosts can damage or kill young leaves. </p>
<p>Flowers are also vulnerable to unpredictable spring frosts because they contain lots of water. If the flowers of fruit trees, such as apples, are killed by frost, the trees won’t produce fruit later in the summer. Late frosts also can cause disappointingly short flowering seasons for early-flowering ornamental plants such as forsythias and magnolias. </p>
<h2>Plant wake-up calls</h2>
<p>To guard against frost and still take advantage of the full growing season, trees and shrubs have developed three ways to know when it is time to start growing in spring. </p>
<p>First, plants have winter chilling requirements: They hold on to winter dormancy until they have been exposed to a certain number of cold winter days. This trait helps them avoid leafing or flowering during abnormally warm periods in midwinter. </p>
<p>Second, plants also have spring warming requirements that promote growth after they experience a certain number of warm days each spring. This feature helps them start to grow as soon as it is warm enough. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="New green leaves on a rhododendron bush." src="https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/387316/original/file-20210302-19-jtjsin.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">For woody plants like this rhododendron, the timing of spring leaf-out is a balance between maximizing their growing seasons and avoiding late frosts.</span>
<span class="attribution"><span class="source">Richard Primack</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Third, some plants also have a <a href="http://www.biologyreference.com/Ph-Po/Photoperiodism.html">photoperiod</a> response, which means they react to the length of time they are exposed to light in a 24-hour period. This prepares them to leaf out as days get longer and warmer in the spring. Beech trees have both a warming requirement and a photoperiod response, but the temperature requirement is much stronger, so they get going after just a few warm days in late spring.</p>
<p>Interestingly, North American trees such as red maple and black birch are more cautious and conservative than European and East Asian trees. The weather in eastern North America is more variable, and the threat of late spring frosts is higher here than in those regions. As a result, North American trees have evolved to leaf out a few weeks later than comparable trees from Europe and East Asia.</p>
<h2>Climate change scrambles the signals</h2>
<p>Plants are highly attuned to temperature signals, so warming driven by climate change is making it harder for many species to withstand winter cold and spring frosts. As spring temperatures get warmer than in the past, trees such as apples and pears may respond by leafing out and flowering <a href="https://www.americanscientist.org/article/spring-budburst-in-a-changing-climate">several weeks earlier than normal</a>. This can increase their vulnerability to late frosts.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cherry branch with blooms and wilted dark leaves." src="https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=604&fit=crop&dpr=1 754w, https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=604&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/387320/original/file-20210302-13-1tn11ts.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=604&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The leaves on this cherry tree have suffered damage from a late frost.</span>
<span class="attribution"><span class="source">Richard Primack</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Such late frosts are <a href="https://doi.org/10.1111/geb.13088">becoming more common</a> because <a href="https://theconversation.com/what-exactly-is-the-polar-vortex-153958">climate change is destabilizing the jet stream</a>, leading it to dip much farther south, bringing bursts of unusually cold weather.</p>
<p>In 2007, an exceptionally warm period in March <a href="https://doi.org/10.1111/j.1469-8137.2011.03803.x">triggered trees to leaf out</a> across the eastern and central United States. A hard frost in April then killed the young leaves and flowers of oaks, hickories and other tree species. The trees were able to produce a second crop of leaves, but could not fully replace the leaves they’d lost, which quite likely stunted their growth for that year. </p>
<p>Insect pests also pose an increasing threat to plants. Harsh winter weather holds in check many insects found in northern climates, such as <a href="https://www.nrs.fs.fed.us/disturbance/invasive_species/hwa/">hemlock woolly adelgids</a> and <a href="https://www.aphis.usda.gov/aphis/maps/plant-health/eab-storymap">emerald ash borers</a>. As winters become milder, these insects are more likely to survive, move further northward, cause major outbreaks and damage trees. </p>
<p>Warmer winters also lead to more days when the ground is bare. Cold snaps that occur when there is no insulating layer of snow can <a href="https://theconversation.com/climate-change-is-shrinking-winter-snowpack-which-harms-northeast-forests-year-round-103410">freeze the soil and kill roots</a>. Tree and shrub branches then die back because the damaged roots cannot supply enough water and nutrients. In extreme cases, the plants may die. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/4pSYC8g5oVM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The U.S. Department of Agriculture’s Plant Hardiness Zone Map shows that these zones – areas where various plant species are most likely to thrive – are shifting northward as climate change warms the U.S.</span></figcaption>
</figure>
<p>In coming decades, many cold-loving tree species such as spruces and firs will become less abundant when they are not able to handle <a href="https://www.fs.fed.us/nrs/pubs/gtr/gtr_nrs173.pdf">new challenges associated with a warmer climate</a>. In the Northeast U.S., native species such as sugar maple and beech will be gradually replaced by native species from farther south, such as oaks and hickories. And nonnative species, such as <a href="https://doi.org/10.1093/treephys/tps092">Norway maples</a>, are taking advantage of these disruptions to disperse into forests from roadsides and neighborhoods.</p>
<p>Similar shifts are happening in many places as climate change alters the signals plants rely on to mark the changing seasons.</p>
<p>[<em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>.]</p><img src="https://counter.theconversation.com/content/155343/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard B. Primack does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Trees and shrubs in cold-weather climates rely on certain signals, such as temperature and light, to know when to leaf out and bloom. Climate change is scrambling those signals.Richard B. Primack, Professor of Biology, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1494552020-11-15T18:51:21Z2020-11-15T18:51:21ZIt’s getting hotter, so spiders are emerging. Should I be alarmed?<figure><img src="https://images.theconversation.com/files/369214/original/file-20201113-21-dg2ngn.JPG?ixlib=rb-1.1.0&rect=131%2C31%2C5044%2C3414&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Golden orbweaver spiders may appear in your gardens.
</span> <span class="attribution"><span class="source">Samantha Nixon</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In spring and summer every year, stories about “<a href="https://www.popsci.com/hordes-spiders-are-raining-down-australia-right-now/">hordes of spiders</a>” and “<a href="https://www.newsweek.com/spider-venomous-flesh-rotting-bite-furniture-mexico-1476701">flesh-eating venom</a>” fill tabloids and social media. </p>
<p>This rhetoric greatly exaggerates the relative risk of Australian spiders, leading to excessive pesticide use and <a href="https://theconversation.com/spider-home-invasion-season-why-the-media-may-be-to-blame-for-your-arachnophobia-147115">unnecessary phobias</a>. </p>
<p>There are more than <a href="https://wsc.nmbe.ch/">49,000 species of spiders in the world</a> and around <a href="http://www.arachne.org.au/">4,000 of these live in Australia</a>, many with astounding behaviours, beautiful colours and natural, biological pest control potential. We should be celebrating the diversity of our spiders in Australia — and what better time than right now?</p>
<p>Many insects and spiders have been growing over the winter months to emerge once the weather gets warmer. This means you’re probably going to start noticing more spiders around your house and garden. So which ones should you worry about?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="St Andrews cross spider on its unique web" src="https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369225/original/file-20201113-13-1ux2i5f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">St Andrews cross spiders build beautiful, unique webs, and the spider sits with its legs in pairs.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Don’t fear these common household spiders</h2>
<p>Some spiders like to live in houses. It’s cool, dry and there are <a href="https://peerj.com/articles/1582/">hundreds of tasty insects</a> to eat that you may not have even noticed, such as silverfish, book lice and springtails.</p>
<p>One of the most common spiders people find at home across Australia is, true to its name, the <a href="https://australian.museum/learn/animals/spiders/black-house-spider-badumna-insignis/">black house spider</a>. These spiders build messy webs on fences and in the corners of windows. </p>
<p>Because they’re black, people can mistake these spiders for funnel-webs, but black house spiders are smaller and harmless. Also, a funnel-web will never make a web in your window.</p>
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Read more:
<a href="https://theconversation.com/i-travelled-australia-looking-for-peacock-spiders-and-collected-7-new-species-and-named-one-after-the-starry-night-sky-135201">I travelled Australia looking for peacock spiders, and collected 7 new species (and named one after the starry night sky)</a>
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<p>In your garden you may spot webs with a white cross (from <a href="http://www.arachne.org.au/01_cms/details.asp?ID=1022">St Andrews cross spiders</a>, <em>Argiope keyserlingi</em>), with leaf retreats (from <a href="http://www.arachne.org.au/01_cms/details.asp?ID=1702">leaf curling spiders</a>, <em>Phonognatha graeffei</em>), or golden silk (from <a href="http://www.arachne.org.au/01_cms/details.asp?ID=910">golden orb weaving spiders</a>, <em>Trichonephila sp.</em>). While impressive, these spiders are shy and their venom is harmless. </p>
<p>Even larger are huntsman spiders (from the <em>Sparassidae</em> family). While they’re famously fast moving, their bites are rare and, at worst, cause mild to moderate pain. </p>
<p>The good news is the vast majority of Australian spiders are harmless. In fact, a global study found less than <a href="https://www.sciencedirect.com/science/article/abs/pii/S0041010117302696?via%3Dihub">0.5% of spiders are dangerous to humans</a>. </p>
<p>However, Australia is home to a number of “medically significant” spiders whose bites can be severe. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Huntsman spider on a tree" src="https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369219/original/file-20201113-19-uu9gi5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Huntsmans are huge, but generally harmless.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Funnel-webs are emerging from their burrows</h2>
<p>First and foremost are funnel-web spiders, which are in the <em>Atracidae</em> family. Sydneysiders are likely well aware of the infamous Sydney funnel-web spider (<em>Atrax robustus</em>), but there are actually around 40 species of funnel-web spiders spread up and down the east coast of Australia. </p>
<p>Most funnel-webs will spend their lives hidden in their burrow. But during spring and summer, male spiders will wander about the bush (and sometimes back gardens) looking for mates, increasing the risk of human contact. </p>
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<strong>
Read more:
<a href="https://theconversation.com/i-didnt-mean-to-hurt-you-new-research-shows-funnel-webs-dont-set-out-to-kill-humans-146406">'I didn't mean to hurt you': new research shows funnel webs don't set out to kill humans</a>
</strong>
</em>
</p>
<hr>
<p>Recent studies into funnel-web venom evolution have shown male Sydney funnel-webs have a high concentration of a toxin called “delta-hexatoxin”, which disrupts neuronal signalling and can lead to respiratory and cardiac failure. This helps them catch insect prey and defend themselves by causing pain in predators. </p>
<p>But through a <a href="https://theconversation.com/i-didnt-mean-to-hurt-you-new-research-shows-funnel-webs-dont-set-out-to-kill-humans-146406">quirk of evolution</a>, this toxin can be fatal to humans.</p>
<p>The hexatoxins are <a href="https://www.pnas.org/content/117/40/24920">distributed throughout</a> the funnel-web family. To date, serious bites have only been reported from funnel-webs in southern Queensland and NSW. This <a href="https://www.mja.com.au/journal/2005/182/8/funnel-web-spider-bite-systematic-review-recorded-clinical-cases">includes</a> the Sydney, Blue Mountains, Toowoomba/Darling Downs and the Northern Tree-dwelling funnel-web spiders. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Sydney funnel-web raising its legs" src="https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369220/original/file-20201113-19-1ogdgp8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=515&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Funnel-web spiders spend most their lives hidden in a burrow.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Mouse spiders and redbacks</h2>
<p>Mouse spiders (<em>Missulena sp.</em>) also have a toxin similar to hexatoxin in their venom, so their bites have <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038753">similar effects</a>. Like the funnel-webs, there are <a href="https://australian.museum/learn/animals/spiders/mouse-spiders/">species of mouse spiders all over Australia</a>.</p>
<p>Fortunately, <a href="https://www.mja.com.au/journal/2004/180/5/mouse-spider-bites-missulena-spp-and-their-medical-importance">clinical studies</a> suggest serious mouse spider bites are rare, but these spiders should still be treated with caution. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Mouse spider crawling on a rock" src="https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=326&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=326&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=326&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=409&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=409&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369218/original/file-20201113-17-5nfgea.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=409&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mouse spiders are best avoided.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>And then there’s the renowned Australian redback spider (<em>Latrodectus hasselti</em>), with its striking red stripe. These spiders are <a href="https://australian.museum/learn/animals/spiders/redback-spider/">found across the continent</a>.</p>
<p>Redback spiders are related to American black widows and have toxins called latrotoxins, which also disrupt neuronal signalling in their prey. (It’s the female redbacks you need to keep an eye out for.) </p>
<p>Redbacks have a <a href="https://www.mja.com.au/journal/2003/179/2/latrodectism-prospective-cohort-study-bites-formally-identified-redback-spiders">painful bite</a> and symptoms can persist for several days. Fortunately for both redbacks and funnel-webs, effective antivenom treatments are available. If bitten, it’s always best to seek medical attention. </p>
<p>It’s worth noting no one has died directly from a spider bite in Australia in more than 40 years since the <a href="https://australian.museum/learn/animals/spiders/funnel-web-spiders-group/#:%7E:text=An%20antivenom%20for%20the%20Sydney,have%20occurred%20since%20its%20introduction.">introduction of antivenom</a>. So while Australian spiders may have a fearsome reputation, it’s somewhat overblown. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369217/original/file-20201113-21-1x5zdw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The infamous redback spider (<em>Latrodectus hasselti</em>) is one of Australia’s few spiders capable of serious envenomation.</span>
<span class="attribution"><span class="source">Sam Robinson</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What to do with spiders in your house and garden</h2>
<p>The first thing you should ask yourself is, do I need to get rid of them at all? </p>
<p>Spiders play an important role in the control of pests such as cockroaches and mosquitoes, so much so that each year, spiders <a href="https://link.springer.com/article/10.1007/s00114-017-1440-1">eat more insect biomass than the weight of the entire human population</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black house spider against a wall" src="https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=395&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=395&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=395&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=497&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=497&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369223/original/file-20201113-17-q0iep3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=497&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Black house spiders build messy webs.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>If you come face to face with an unwanted spider in your house, we recommend using a container and piece of paper for a simple catch-and-release into the garden. If the webs are what bothers you — and we’ve all walked face-first through a web at some point — sweeping them away will usually be enough for the spider to move on.</p>
<p>Alternatively, you can leave the webs in the garden to catch other insects (think of them as functional, miniature artworks).</p>
<p>Redbacks have a habit of building their webs under, for example, the rims of pot plants and in outdoor furniture. This can be a problem, especially for small children. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dont-like-spiders-here-are-10-reasons-to-change-your-mind-126433">Don't like spiders? Here are 10 reasons to change your mind</a>
</strong>
</em>
</p>
<hr>
<p>So keeping your house and garden tidy, regularly sweeping and avoiding leaving junk lying around makes your garden less attractive for web-building. </p>
<p>It’s also good to avoid leaving shoes outside (or shaking them out) and checking your swimming pools for lost wandering spiders. This will help prevent accidental contact with funnel-webs during spring and summer. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bQABY9H1h1Y?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Using amazing close-up footage, Sir David Attenborough explores the world of the redback spider.</span></figcaption>
</figure>
<p>If you really have to kill a redback, a quick squish with the shoe is far better than using pesticides, which have negative impacts on <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119255574.ch11">human health</a> and the <a href="https://link.springer.com/article/10.1007/s11356-014-3277-x">environment</a>. This includes polluting streams, harming birds and bees, and leading to <a href="https://pubmed.ncbi.nlm.nih.gov/26758450/">insecticide resistance in pests</a> such as cockroaches and mosquitoes. </p>
<p>Spiders are a key part of Australia’s native ecosystems, <a href="https://link.springer.com/article/10.1007/s10531-017-1466-x">including in cities</a>. The harm we do to our own health and the environment by using excessive pesticides far outweighs the risk spiders pose to us. </p>
<p>If we can learn to live alongside these not-so-creepy crawlies, our houses and gardens will be better for it. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/spider-home-invasion-season-why-the-media-may-be-to-blame-for-your-arachnophobia-147115">Spider home invasion season: why the media may be to blame for your arachnophobia</a>
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<hr>
<img src="https://counter.theconversation.com/content/149455/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>We identify a few harmless spiders you’ve probably seen around the house and backyard — and a few that are best avoided.Lizzy Lowe, Postdoctoral researcher, Macquarie UniversitySamantha Nixon, PhD, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1461092020-09-29T20:01:34Z2020-09-29T20:01:34ZOnce again, wattles are out in bloom: here’s what makes our iconic flowers so special<figure><img src="https://images.theconversation.com/files/359953/original/file-20200925-14-11k2voc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Spring has arrived, and all over the country the hills and riversides are burnished with the green and gold of Australian wattles, all belonging to the genus <em>Acacia</em>. </p>
<p>It’s a spectacular sight, but not a surprising one as there are about 1,000 Australian species in the <a href="http://www.anbg.gov.au/acacia/"><em>Acacia</em></a> genus ranging from very small shrubs to tall, longed-lived trees. They occur in ecosystems from the arid inland to the wet forests of the east coast. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tree-ferns-are-older-than-dinosaurs-and-thats-not-even-the-most-interesting-thing-about-them-138435">Tree ferns are older than dinosaurs. And that's not even the most interesting thing about them</a>
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</p>
<hr>
<p>Wattles have been widely used by Indigenous people for millenia, and celebrated by “<a href="http://www.wattleday.asn.au/about-wattles/what-do-you-know-a-few-wattle-facts">Wattle Day</a>” on September 1 for more than a century. </p>
<p>But their lineage may be much older. Australian wattles have relatives in Africa, South America, India and parts of Southeast Asia. This distribution suggests the wattles may have originated in Gondwana before the super-continent fragmented about 180 million years ago. </p>
<p>So let’s take a closer look at what makes these iconic flowers so special. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Wattle on a cloudy day" src="https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/359954/original/file-20200925-20-90ckdc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wattle can always brighten a dreary day.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Don’t blame wattles for your hay fever</h2>
<p>Not everyone welcomes the wattles’ golden blooms — many blame wattle pollen for their hay fever or asthma. </p>
<p>However, many species of wattle have <a href="https://www.abc.net.au/news/health/2015-09-23/dont-blame-the-wattle/6791396">aggregated pollen</a>, which means it’s very heavy and tends to fall straight to ground. You have to be virtually under the plant for it to affect you. </p>
<p>They can cause trouble, but it’s more likely your allergy is due to some other inconspicuous plant, such as grass, that you haven’t noticed compared to the bright yellow of the wattles. It’s worth having an allergy test.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-manage-grass-pollen-exposure-this-hay-fever-season-an-expert-guide-123271">How to manage grass pollen exposure this hay fever season: an expert guide</a>
</strong>
</em>
</p>
<hr>
<p>While a majority of wattles flower in spring and summer, a significant group — such as the sunshine wattle (<em>A. botrycephala</em>), Gawler Range wattle (<em>A. iteaphylla</em>) and flax wattle (<em>A linifolia</em>) — flowers in <a href="https://www.abc.net.au/science/articles/2003/07/03/2578547.htm">autumn and winter</a>. This can give the impression in some places that they’re flowering year-round. </p>
<p>What’s more, many species are hardy, and they can help in the process of taking nitrogen from the air and adding to the soil. That means they can be very handy in ancient, nutrient-poor Australian soils. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A mulga in the Australian desert" src="https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=521&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=521&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=521&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=654&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=654&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360472/original/file-20200929-14-1r2142v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=654&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mulga grows over about 20% of our continent.</span>
<span class="attribution"><span class="source">Mark Marathon/Wikimedia</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Many of the smaller shrub wattles may live for only a decade or so, but some, <a href="http://theconversation.com/the-mighty-mulga-grows-deep-and-lives-long-118838">such as mulga</a> (<em>Acacia aneura</em>) can live for centuries and are crucial to the viability and stability of arid inland ecosystems. They can have surprisingly large and deep root systems for such small shrubs or trees. This is to obtain water, but also binds the soil.</p>
<p>However, mulga-munching horses, cattle and other feral grazers threaten the persistence of mulga-dominated communities. If mulga and other inland <em>Acacia</em> species are lost, the soils can become loose and mobile, which results in stable productive land becoming desert.</p>
<h2>By any other name</h2>
<p>In the early 2000s, there was <a href="https://www.australiangeographic.com.au/topics/wildlife/2016/03/the-wattle-war/">fierce debate</a> among plant taxonomists about how closely the African and Australian species were related. </p>
<p>The name “Acacia” rightly belonged to the African group, but because there were so many Australian species that would need to be renamed, Australia was allowed to keep the name “Acacia” in 2011 — much to the chagrin of foreign taxonomists. </p>
<p>This resulted in the genus being divided. Australian wattles stayed as <em>Acacia</em>, but African wattles are now in the genera <em>Vachellia</em> or <em>Senegalia</em>, and those from the middle Americas (around Mexico) are <em>Acaciella</em> and <em>Mariosousa</em>. </p>
<p>The different names reflect long, separate histories and different ecological characteristics. (The name changes rankle still with taxonomists!) </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of black wattle flowers" src="https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360467/original/file-20200929-22-65x56c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Black wattle is a pest overseas.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>There are also weedy wattles in Australia and elsewhere. Many of us know from hard experience that the splendid ornamental tree, Cootamundra wattle (<em>Acacia baileyiana</em>), can become a weed if it grows outside its very restricted natural range in New South Wales. And Australia’s <a href="http://theconversation.com/the-black-wattle-is-a-boon-for-Australians-and-a-pest-everywhere-else-100529">black wattle</a> (<em>A. mearnsii</em>) is a significant weed in other parts of the world. </p>
<p>It can come as a bit of a blow to know Australia’s floral emblem, golden wattle (<em>A. pycnantha</em>), can be weedy both at home and when it travels abroad (perhaps like some Australians). </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-black-wattle-is-a-boon-for-australians-and-a-pest-everywhere-else-100529">The black wattle is a boon for Australians (and a pest everywhere else)</a>
</strong>
</em>
</p>
<hr>
<p>Interestingly, most of the Australian wattles lack thorns, unlike <a href="http://worldwidewattle.com/schools/animals.php">their relatives in Africa</a>. In Africa, thorns protect the plants from large mammalian grazers such as giraffes. </p>
<h2>Ants love wattles, too</h2>
<p>If you don’t like ants, it might be worth checking which species of wattle you have in your backyard, or intend to buy.</p>
<p>Many wattles have a very special relationship with some insects. In Central America, ants penetrate the thorns of Bulls Horn wattle trees and establish their colonies. They then defend the tree against other insects, and if branches of another tree touch the host tree, the ants will cause such damage that the other tree will die back. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360464/original/file-20200929-20-dftc3q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">There are more than 1,000 species of wattle in the <em>Acacia</em> genus.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>In Australia, the relationship between ants and wattles is based on food. The hard wattle seeds have a tasty and oil-rich outgrowth called an “aril”, which is irresistible to some ant species. </p>
<p>The ants harvest the seeds and take them back to their nest, where they’re safe from other hungry grazers until it is damaged by fire or flood and the seeds germinate. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-tiny-ants-have-invaded-your-house-and-what-to-do-about-it-132092">Why tiny ants have invaded your house, and what to do about it</a>
</strong>
</em>
</p>
<hr>
<p>Some wattles, the mulga among them, have little <a href="http://worldwidewattle.com/schools/animals.php">glands</a> at the base of their phyllodes (the modified leaf stalks). These glands secrete a form of sugary syrup that attracts feeding ants. These ants may also protect host trees or perhaps leave the flowers alone to allow a greater seed set to grow. </p>
<p>It’s clear wattles have a lot going for them. They are diverse in number, habit, size, longevity and flowering season — there’s a wattle for every occasion. For all of these great traits, it’s still that green and gold that endears them to Australians.</p><img src="https://counter.theconversation.com/content/146109/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gregory Moore does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>With their vibrant blooms and a lineage tracing back to the ancient supercontinent of Gondwana, wattles have a lot going for them.Gregory Moore, Doctor of Botany, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1457652020-09-28T19:59:51Z2020-09-28T19:59:51ZDoes Australia really have the deadliest snakes? We debunk 6 common myths<figure><img src="https://images.theconversation.com/files/360213/original/file-20200928-18-zezqar.JPG?ixlib=rb-1.1.0&rect=0%2C24%2C4031%2C2993&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A red-bellied black snake </span> <span class="attribution"><span class="source">Damian Michael</span>, <span class="license">Author provided</span></span></figcaption></figure><p>As we settle into spring and temperatures rise, snakes <a href="https://about.unimelb.edu.au/newsroom/news/2018/september/snake-season-no-cause-for-alarm-if-youre-prepared">are emerging</a> from their winter hideouts to bask in the sun. But don’t be alarmed if you spot one, it’s hard to imagine a more misunderstood group of animals than snakes. </p>
<p>Our interactions with snakes are conversation starters, with yarns told and retold. But knowing what’s fact and fiction gets harder with each retelling. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ive-always-wondered-who-would-win-in-a-fight-between-the-black-mamba-and-the-inland-taipan-129906">I've always wondered: who would win in a fight between the Black Mamba and the Inland Taipan?</a>
</strong>
</em>
</p>
<hr>
<p>As is so often the case with wildlife, the myths pale in comparison to what science has shown us about these incredible creatures. So let’s debunk six misconceptions we, as wildlife ecologists, often hear. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A snake warning sign" src="https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360212/original/file-20200928-22-sdai57.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">With snakes on the move this season, people and pets are more likely to spot them.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>1. Black snakes and blue tongue lizards keep brown snakes away</h2>
<p>This is a <a href="https://www.thecourier.com.au/story/3545112/snake-1-blue-tongue-0/">common old wives’ tale</a> in southern Australia. The myth goes that if you see a red-bellied black snake or a blue-tongue lizard on your property, you’re unlikely to see the highly venomous brown snake, because black snakes keep brown snakes at bay. </p>
<p>This myth probably originates from observations of black snakes eating brown snakes (which <a href="https://researchoutput.csu.edu.au/en/publications/a-case-of-predation-by-an-adult-red-bellied-black-snake-pseudechi">they do</a>).</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/T6BrH_yvvlA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>But it’s not one-way traffic. There are many reported examples of brown snakes <a href="https://www.thecourier.com.au/story/4986213/farmer-discovered-its-a-snake-eat-snake-world/?cs=2452#slide=2">killing black snakes</a>, too. Overall, no scientific evidence suggests one suppresses the other. </p>
<p>There is also no evidence blue-tongue lizards prey upon or scare brown snakes. In fact, many snakes feed on lizards, including brown snakes which, despite <a href="https://www.jstor.org/stable/3892162?seq=1#metadata_info_tab_contents">a preference for mammal prey</a> as adults, won’t hesitate to have a blue tongue for lunch.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/60kOWFtumc0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>2. Snakes are poisonous</h2>
<p>While the term poisonous and venomous are often used interchangeably, they mean quite different things. If you eat or ingest a toxic plant or animal, it’s said to be poisonous, whereas if an animal stings or bites you and you get sick, it’s venomous. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-are-some-snakes-so-venomous-22821">Why are some snakes so venomous?</a>
</strong>
</em>
</p>
<hr>
<p><a href="https://www.science.org.au/curious/people-medicine/poison-vs-venom">Venom is a specialised type of poison</a> that has evolved for a specific purpose. For venom to work, it needs a wound to enter the body and into the bloodstream. Snakes, therefore, are generally venomous, not poisonous.</p>
<p>But there are <a href="https://link.springer.com/article/10.1023/B:JOEC.0000045585.77875.09">exceptions</a>. For example, the American garter snake preys on the rough-skinned newt which contains a powerful toxin. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black and red garter snake." src="https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360204/original/file-20200928-14-1iyamxo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The toxins from the rough-skinned newt can stay in a garter snake’s liver for up to a month.</span>
<span class="attribution"><span class="source">Steve Jurvetson/Wikimedia</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The newt’s toxin accumulates in the snake’s liver, and effectively makes this non-venomous snake species poisonous if another animal or human eats it. Remarkably, these snakes can also assess whether a given newt is <a href="https://meridian.allenpress.com/herpetologica/article-abstract/59/2/155/32411/COEVOLUTION-OF-DEADLY-TOXINS-AND-PREDATOR?redirectedFrom=fulltext">too toxic for them to handle</a>, and so will avoid it.</p>
<h2>3. Australia has the deadliest snakes in the world</h2>
<p>Approximately 20% of the world’s 3,800-plus snake species are venomous. Based on the median lethal dose — the standard measurement for how deadly a toxin is — the Australian inland taipan is ranked number one in the world. Several other Australian snakes feature in the top 10. But does that make them the deadliest? </p>
<p>It depends on how you define “deadly”. Death by snake bite in Australia is very uncommon, with just <a href="https://onlinelibrary.wiley.com/doi/full/10.5694/mja17.00094">two per year</a>, on average, compared to <a href="https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(19)31232-2.pdf">81,000-138,000 deaths</a> from snakes annually worldwide.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/yes-australian-snakes-will-definitely-kill-you-if-youre-a-mouse-51809">Yes, Australian snakes will definitely kill you – if you're a mouse</a>
</strong>
</em>
</p>
<hr>
<p>If we define “deadly snakes” as those responsible for killing many people, then the list would be topped by snakes such as the Indian cobra, common krait, Russell’s viper and the saw-scaled viper, which occur in densely populated parts of India and Asia. </p>
<p>A lack of <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31224-8/fulltext">access to antivenoms and health care contribute</a> substantially to deaths from snake bites.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An Indian cobra upright on a log" src="https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360206/original/file-20200928-18-1b4r07v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Indian cobra’s are one of the deadliest snakes in the world.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>4. Snakes have poor eyesight</h2>
<p>Compared to other reptiles, such as monitor lizards, most snakes have poor eyesight, especially species that are active <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/9780470015902.a0026519">at night or burrow in soil</a>. </p>
<p>However, snakes that are active by day and feed on fast-moving prey have relatively good vision. </p>
<p><a href="https://www.publish.csiro.au/WR/pdf/WR98043">One study</a> in 1999 showed people are less likely to encounter eastern brown snakes when wearing clothing that contrasted with the colour of the sky, such as dark clothing on a bright day. This suggests they can see you well before you see them. </p>
<p>Some snakes such as the American coachwhip <a href="https://jeb.biologists.org/content/216/22/4190.full">can even improve their eyesight</a> when presented with a threat by constricting blood vessels in the transparent scale covering the eye. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A sea snake dives underwater" src="https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360208/original/file-20200928-14-1o0em9d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An olive sea snake can actually detect light through their tail.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>And then there’s the olive sea snake, whose “<a href="https://www.jstor.org/stable/1446454?seq=1#metadata_info_tab_contents">phototactic tails</a>” can sense light, allowing them to retract their tails under shelter to avoid predation. </p>
<h2>5. Young snakes are more dangerous than adults</h2>
<p>This myth is based on the idea juvenile snakes can’t control the amount of venom they inject. No evidence suggests this is true. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-what-should-you-do-if-youre-bitten-by-a-snake-34238">Explainer: what should you do if you're bitten by a snake?</a>
</strong>
</em>
</p>
<hr>
<p>However, research shows the venom of <a href="https://www.mdpi.com/2072-6651/8/11/309">young and old snakes can differ</a>. A <a href="https://www.sciencedirect.com/science/article/pii/S1532045617300923">2017 study</a> showed the venom of young brown snakes is different to adults, probably to facilitate the capture of different types of prey: young brown snakes feed on reptiles, <a href="https://www.jstor.org/stable/3892162?seq=1#metadata_info_tab_contents">whereas</a> adult brown snakes predominantly feed on mammals. </p>
<p>But it’s not just age — <a href="https://www.sciencedirect.com/science/article/pii/S1874391918301398">venom toxicity can vary</a> among <a href="https://www.sciencedirect.com/science/article/pii/S1096495901004225">individuals of the same population</a>, or among <a href="https://www.tandfonline.com/doi/pdf/10.1081/TXR-120019018">populations</a> of the same species. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black snake with white stripes on a rock." src="https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360196/original/file-20200928-24-1gekeb0.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bandy Bandy (<em>Vermicella annulata</em>). Defensive behaviours are often misinterpreted as aggression.</span>
<span class="attribution"><span class="source">Damian Michael</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>6. Snake are aggressive</h2>
<p>Perhaps the most pervasive myth about snakes is they’re aggressive, probably because defensive behaviours are often misinterpreted. </p>
<p>But snakes don’t attack unprovoked. Stories of snakes chasing people are more likely cases where a snake was attempting to reach a retreat site behind the observer. </p>
<p>When threatened, many snakes give a postural warning such as neck flaring, raising their head off the ground, and opening their mouths, providing clear signals they feel threatened. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/TXNxMCRBTkA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>It’s fair to say this approach to dissuade an approaching person, or other animal, works pretty well. </p>
<p>Rhesus macaques display <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/eth.12293">more fearful behaviour</a> when confronted with snakes in a striking pose compared to a coiled or elongated posture. And showing Japanese macaques <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0114258">images of snakes in a striking posture</a> sets of a flurry of brain activity that isn’t evoked when they’re shown images of snakes in nonthreatening postures. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/new-research-reveals-these-20-australian-reptiles-are-set-to-disappear-by-2040-145385">New research reveals these 20 Australian reptiles are set to disappear by 2040</a>
</strong>
</em>
</p>
<hr>
<p>The same is true for humans. Children and adults detect images of snakes in a striking posture <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0015122">more rapidly</a> than a resting posture. And a <a href="https://www.nature.com/articles/s41598-020-63619-y">study</a> from earlier this year found human infants (aged seven to 10 months) have an innate ability to detect snakes. </p>
<p>Snakes are amazing, but shouldn’t be feared. If you encounter one on a sunny day, don’t make sudden movements, just back away slowly. Never pick them up (or attempt to kill them), as this is often when people are bitten.</p><img src="https://counter.theconversation.com/content/145765/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Damian R. Michael receives funding from the Commonwealth Environmental Water Office and has received funding from the National Environmental Science Program Threatened Species Recovery Hub. </span></em></p><p class="fine-print"><em><span>Dale Nimmo receives funding from the Australian Research Council, The Hermon Slade Foundation, the Department of Biodiversity, Conservation and Attractions, the National Environmental Science Program Threatened Species Recovery Hub and the Australian Academy of Science</span></em></p><p class="fine-print"><em><span>Skye Wassens receives funding from the Commonwealth Environmental Water Office and has received funding from the New South Wales Department of Planning, Industry and Environment.</span></em></p>The weather is warming up, and snakes are coming out to bask in the sun. But we don’t need to tell tall tales to appreciate snakes – the truth is far more fascinating.Damian R. Michael, Senior research fellow, Charles Sturt UniversityDale Nimmo, Associate Professor in Ecology, Charles Sturt UniversitySkye Wassens, Associate Professor in Ecology, Charles Sturt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1303842020-05-11T17:57:51Z2020-05-11T17:57:51ZLonger growing seasons have a limited effect on combating climate change<figure><img src="https://images.theconversation.com/files/333260/original/file-20200506-49569-yn2dzp.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4031%2C3024&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An early spring bloom in Toronto, taken on April 1, 2020.</span> <span class="attribution"><span class="source">(Alemu Gonsamo)</span></span></figcaption></figure><p>Climate warming is leading to early springs and delayed autumns in colder environments, allowing plants to <a href="https://doi.org/10.1016/j.rse.2016.04.022">grow for a longer period of time</a> during each growing season. Plants are <a href="https://doi.org/10.1111/gcb.14001">absorbing more carbon dioxide (CO2)</a> as a result of this longer growing season. </p>
<p>The earlier arrival of spring is fighting climate change by allowing plants to absorb CO2 over a longer period of time and thus slowing the rate at which atmospheric CO2 is rising. What we don’t know is how long can we count on earlier springs and longer growing seasons.</p>
<p>I am a remote sensing scientist who studies the impact of climate change on seasonal cycle of plant activity. Using satellite observations, long-term ground measurements and mechanistic computer models, I also study the impacts of climate change and variability on global land ecosystems and related feedbacks to the atmosphere through carbon cycle.</p>
<h2>Changing growing seasons</h2>
<p>Spring leaf-out — when the first leaves start to appear on plants — is arriving earlier for many temperate, boreal and Arctic plants. Thirty-four years of satellite records reveal not only an earlier leaf-out, but also a <a href="https://doi.org/10.1111/gcb.14001">shift in peak plant growth timing towards spring for plants growing north of the tropics</a>. </p>
<p>In Canada, <a href="https://www.naturewatch.ca/plantwatch/">PlantWatch enables citizen scientists to record leaf-out and flowering times in all provinces and territories</a>. The PlantWatch data show the average date the first flower blooms in 19 plant species has <a href="https://doi.org/10.1038/srep02239">advanced by about nine days for each corresponding rise of one degree Celsius</a> in air temperature. The bloom dates of the earliest-blooming species — such as trembling aspen and prairie crocus — advanced by <a href="https://doi.org/10.1525/bio.2011.61.7.6">two weeks</a> during the past seven decades of the past century.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/333261/original/file-20200506-49538-h01uuk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Prairie crocuses, already one of the earliest-blooming plants, are showing up earlier in the year due to global warming.</span>
<span class="attribution"><span class="source">(Alemu Gonsamu)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As a consequence of warming temperatures, leaf senescence (leaf colouring and leaf fall) in autumn is also delayed. Researchers using 54 years data records in Japan and South Korea found that autumn <a href="https://doi.org/10.1098/rstb.2010.0120">leaf fall is occurring later</a>. Long-term satellite data also show <a href="https://doi.org/10.1111/gcb.14001">delayed leaf senescence</a> for the majority of temperate and boreal plants. </p>
<p>The combination of earlier spring and delayed autumn means a longer growing season. The resulting longer growing season contributes to combating climate change by decreasing atmospheric CO2 buildup.</p>
<h2>Carbon dioxide absorption</h2>
<p>The increased removal of atmospheric CO2 by plants as a result of longer growing seasons and warming-induced increase in vegetation cover in northern ecosystems has been <a href="https://theconversation.com/yes-more-carbon-dioxide-in-the-atmosphere-helps-plants-grow-but-its-no-excuse-to-downplay-climate-change-130603">widely reported</a>. </p>
<p>As plants absorb atmospheric CO2 in spring and summer, levels of atmospheric CO2 drop in the high latitudes. As plants decompose after the growing season ends, the atmospheric CO2 levels climb up again. </p>
<p>This creates a strong seasonal cycle of atmospheric CO2 concentrations at higher latitudes. The amount of CO2 absorbed by plants, indicated by the difference between early spring and late summer atmospheric CO2 concentration, <a href="https://doi.org/10.1111/gcb.13646">is increasing</a>. The increase in seasonal cycle is a clear indicator of increasing removal of atmospheric CO2 by plants as a result of <a href="https://doi.org/10.1111/gcb.14001">earlier and increased plant growth and longer growing season</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=341&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=341&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=341&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=429&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=429&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323497/original/file-20200327-146662-ou6y42.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=429&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This figure shows the relationship between growing season length and atmospheric CO2 concentration. A longer growing season removes more CO2 from the atmosphere.</span>
<span class="attribution"><span class="source">(Alemu Gonsamo)</span></span>
</figcaption>
</figure>
<h2>Carbon dioxide release</h2>
<p>A longer growing season may also increase CO2 release from ecosystems by prolonging the period during which soils decompose. In order for the land to remain a strong carbon sink, the balance of CO2 gain from the lengthening growing season must outweigh the associated increase in CO2 release.</p>
<p>In northern ecosystems, including Canada, a large proportion of ecosystem carbon is stored in soils, while a small fraction is stored in plants. Warming in autumn delays senescence and, as a result, increases CO2 absorption by plants. However, plant growth in autumn is restricted by shorter day length regardless of warming, thus limiting the potential amount of CO2 absorption. </p>
<p>Conversely, the increase in soil CO2 release from decomposition due to autumn warming is not restricted by shorter day length. CO2 loss from soil decomposition from autumn warming may be <a href="http://dx.doi.org/10.1038/nature06444">greater than</a> the increased CO2 absorption by delayed senescence. In other words, the delayed autumn brings little or no benefit to ecosystem CO2 storage.</p>
<p>In addition, in many northern ecosystems, the benefits of warmer springs on increased CO2 absorption is offset by <a href="http://dx.doi.org/10.1038/s41586-018-0555-7">the accumulation of seasonal water deficits</a>. New evidence shows that the increased spring plant growth and earlier start of the growing season actually deplete summer soil moisture and decrease the overall summer time plant growth in <a href="https://doi.org/10.3390/rs11171989">boreal and tundra ecosystems</a>. With increasing warming throughout the growing season, summer moisture stress may be exacerbated in the future in temperate, boreal and Arctic ecosystems.</p>
<p>Climate change is leading to warmer and longer growing seasons, reduced snow pack in winter, earlier spring snow melt and soil water depletion. This in turn increases moisture stress on plants and makes forests more susceptible to severe wildfire, which already becoming <a href="https://www.macleans.ca/news/canada/climate-change-is-making-wildfires-in-canada-hotter-and-more-dangerous/">increasingly frequent and severe in large parts of Canada</a>. Severe fires can release huge amounts of CO2, not only from the burning plant tissues but also from top soils and peat lands. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/more-frequent-fires-could-dramatically-alter-boreal-forests-and-emit-more-carbon-122355">More frequent fires could dramatically alter boreal forests and emit more carbon</a>
</strong>
</em>
</p>
<hr>
<h2>Combating climate change</h2>
<p>If plant growth keeps increasing as a result of warmer growing seasons, the increasing growing season length could help remove CO2 emissions from the atmosphere. On the other hand, if plant growth actually decreases or if CO2 loss actually increases, then the carbon absorption capacity of northern ecosystems would decline and climate warming could further accelerate.</p>
<p>For now, the net impact of a longer growing season is that plants <a href="https://www.nature.com/articles/nclimate2253">are absorbing more</a> CO2. However, with increasing moisture stress in summer time expected in future, high-latitude ecosystems may not benefit from the lengthening growing season for very long. </p>
<p>There is no question that the lengthening growing season is a fundamental part of the portfolio in nature’s ability to combat climate change. However, policies <a href="https://www.cbc.ca/news/technology/tree-planting-climate-change-1.5201102">that rely on nature’s ability to combat climate change</a> should not count on the benefits of the lengthening growing season for very long.</p><img src="https://counter.theconversation.com/content/130384/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alemu Gonsamo receives funding from NSERC and WWF-Canada</span></em></p>Global warming has increased plant growth and helped offset increases in carbon dioxide emissions.Alemu Gonsamo, Assistant professor, Remote Sensing at School of Geography & Earth Sciences, McMaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1348522020-05-01T12:15:13Z2020-05-01T12:15:13ZSpring signals female bees to lay the next generation of pollinators<figure><img src="https://images.theconversation.com/files/323471/original/file-20200327-132965-b72auj.JPG?ixlib=rb-1.1.0&rect=44%2C6%2C4236%2C2837&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Northern amber bumble bee queen (_Bombus borealis_) on a dandelion flower.</span> <span class="attribution"><span class="source">Sarah A. Johnson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>The first days of spring – brighter and warmer – are a biological trigger for female bees to wake up from hibernation and begin to build future colonies. </p>
<p>These enormous bees, sometimes <a href="https://doi.org/10.1007/s00265-007-0510-3">two to three times larger</a> than a worker bee, are vital to our ecosystem and carry all the genetic material necessary for an entire generation of bees <a href="https://www.jstor.org/stable/25085198">inside their bodies</a>. </p>
<p>If you are lucky, you might see these big bees bumble through spring blossoms in search of food and a new home. Be careful not to disturb them. Killing a few bees during the summer may not have much impact. But the death of a single female bee, ready to reproduce in early spring, could wipe out an entire colony and erase the important services that her offspring would provide – pollinating flowers in gardens, parks, farms and meadows. </p>
<p><a href="https://depts.washington.edu/distecol/people.html">My research</a> explores the foraging behavior of bees. I spend a lot of time in public parks and gardens in Seattle observing bees collecting pollen. I analyze which plants bees have visited and why. In early spring, I sometimes have the privilege of observing female bees as they search for a new home and visit plants to collect nectar for energy in flight. Bees accomplish their reproductive work in both simple and mysterious ways.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323470/original/file-20200326-132965-1v7bxzk.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Western bumble bee queen (<em>Bombus occidentalis</em>) with a male on an aster flower.</span>
<span class="attribution"><span class="source">Sarah A. Johnson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>The wild social bee colony</h2>
<p>Female bees are essential to the survival of all bee colonies, but each species is unique. Bees native to the United States lead different lives from one another depending on whether they are social bees or solitary bees. </p>
<p>Female social bees first begin looking for a new nesting spot – a hole in a tree, an abandoned rat’s nest, an empty mouse burrow – to lay hundreds of offspring to build a colony. At the same time, they collect pollen and nectar to feed the newly hatched bees. Social bee colonies can contain thousands of bees, each performing a different task to keep the colony healthy and safe. </p>
<p>Only the queen bee is fertile and correctly called “queen” if she belongs to a species where adult females live together and cooperate in some way. An estimated 10% of all bee species – of which there are <a href="https://doi.org/10.1073/pnas.0604033103">more than 20,000</a> worldwide – are considered social bees with a queen in charge.</p>
<p>All the female bees laid by a social queen bee are sterile, <a href="https://doi.org/10.1186/1742-9994-9-35">keeping the queen in control</a> and preserving the hierarchy of the hive. The sterile females and males perform low-level work like collecting food and caring for offspring.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323466/original/file-20200326-132965-5ieejm.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Yellow-banded bumble bee queen (<em>Bombus terricola</em>) on willow inflorescence.</span>
<span class="attribution"><span class="source">Sarah A. Johnson, CC BY-ND</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Social queen bees are easily identified because they tend to be active early in the season and are often noticeably larger than most of their offspring. Queen bees can lay hundreds to thousands of eggs over the course of the summer. In the fall, a new queen bee is laid. The remainder of the colony dies off, and the queen overwinters alone, carrying all the genetic material to start a new population the following spring.</p>
<h2>Solitary bees and their habits</h2>
<p>Unlike social bees that live and work together with a single fertile female queen, solitary bees live alone, and all female solitary bees are fertile. Instead of building colonies, female solitary bees emerge in spring and mate with male solitary bees, then find a place to nest, such as a woodpecker hole, the siding of your house or a hole in the ground.</p>
<p>Female solitary bees create segmented nests for each individual offspring. They collect pollen from flowers and build a ball called a <a href="https://doi.org/10.1016/j.jinsphys.2016.09.011">pollen provision</a> inside each segment, anywhere from the size of a lentil to a large pea. Female solitary bees lay a single egg in each segment of the nest that contains a pollen provision, then die off. Solitary bees pollinate a <a href="https://www.jstor.org/stable/10.2307/24969305">huge number</a> of flowering plants in the process of collecting food for their offspring. The offspring overwinter and emerge to continue the cycle the next spring. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323413/original/file-20200326-133016-3mutj3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Honey bee queens lay thousands of offspring over the season, bees that are important for agricultural pollination.</span>
<span class="attribution"><span class="source">Photo by Boba Jaglicic on Unsplash</span></span>
</figcaption>
</figure>
<h2>What about honey bees?</h2>
<p>A well-known social bee that provides pollination services is the non-native honey bee, a species that lives in man-made hives designed to easily transport bees and harvest honey. Honey bees are technically native to Europe, but have been <a href="https://doi.org/10.1016/j.jip.2009.06.011">domesticated by humans</a> for thousands of years. Unlike native social bees that die off in the fall, honey bees hibernate during the winter inside their hives. </p>
<p>When a queen honey bee grows old after two to three years, offspring are designated as future queens and fed a highly nutritious diet of <a href="https://doi.org/10.1155/2017/1259510">royal jelly</a> – a mixture of nectar and pollen. The young queen is <a href="https://doi.org/10.1007/s00265-003-0738-5">raised by her sisters</a> until she reaches maturity. Then she leaves the nest to begin laying offspring and building a colony of her own. The honey bee colony continues to survive, cycling through generation after generation.</p>
<h2>Building ecosystem resilience for bees</h2>
<p>Female bees, responsible for future bee populations, face risks early in the season with limited flowers to visit for energy and a decline in nesting sites in more developed areas. </p>
<p>It’s best to provide female bees with many early spring flowers – they rely on nectar from flowers to fuel their search for a nesting spot. Planting <a href="https://www.xerces.org/blog/planning-your-plantings-for-climate-resiliency">early flowering</a> plants such as willow, poplar, cherry trees and other spring blooms provides nectar for queen bees.</p>
<p>Garden restoration benefits all bees by fostering nesting sites for social and solitary bees. Nesting sites boost bee populations, pollinating native plants and boosting production in our <a href="https://doi.org/10.1007/s11252-014-0349-0">backyard gardens</a> and <a href="https://doi.org/10.1603/0013-8746(2008)101%5B140:BRAAIN%5D2.0.CO;2">community gardens</a>.</p>
<p>How can you help these amazing bees? Simply let them be. If it’s spring and a big bee is too close for comfort, move calmly out of the way and admire her from afar. Female bees, looking for a home, are usually too preoccupied with their search to sting you.</p>
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<p class="fine-print"><em><span>Lila Westreich receives funding from the National Science Foundation and the United States Department of Agriculture McIntire-Stennis Cooperative Forestry Research program.</span></em></p>One bee may lay thousands of offspring in late spring. Give her room to build a nest and manage her reproductive duties.Lila Westreich, Ph.D. Candidate, School of Environment and Forest Sciences, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.