tag:theconversation.com,2011:/africa/topics/funnel-web-spiders-22040/articlesfunnel-web spiders – The Conversation2020-11-15T18:51:21Ztag: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>
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<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>
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<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>
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<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>
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<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>
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<span class="caption">Huntsmans are huge, but generally harmless.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<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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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>
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<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>
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<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>
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<span class="caption">Funnel-web spiders spend most their lives hidden in a burrow.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<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>
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<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>
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<span class="caption">Mouse spiders are best avoided.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<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>
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<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>
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<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>
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<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>
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<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>
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<span class="caption">Black house spiders build messy webs.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<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>
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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>
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<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>
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<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>
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<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>
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<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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<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/1464062020-09-21T19:59:48Z2020-09-21T19:59:48Z‘I didn’t mean to hurt you’: new research shows funnel webs don’t set out to kill humans<figure><img src="https://images.theconversation.com/files/358932/original/file-20200921-16-1fj5n7b.jpeg?ixlib=rb-1.1.0&rect=23%2C0%2C3858%2C2584&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>Funnel webs are considered one of Australia’s <a href="https://australian.museum/learn/animals/spiders/funnel-web-spiders-group/">most fearsome</a> spiders, but their ability to kill humans is by accident rather than design, our new research shows.</p>
<p>In findings <a href="https://www.pnas.org/content/early/2020/09/15/2004516117">published today</a>, we reveal how the highly toxic and quick-acting venom of male funnel-web spiders is likely to have developed as a defence against predators.</p>
<p>When male funnel-web spiders are young, their venom is potent mainly to insects, which they eat. But once males start searching for a female mate, they must leave the safety of their burrows. That’s when their venom becomes potent to vertebrates such as reptiles and mammals – including humans.</p>
<p>So while humans can theoretically die from a funnel web bite, this is just an evolutionary coincidence – our research suggests the spiders aren’t specifically out to get us.</p>
<figure class="align-center ">
<img alt="A funnel web spider" src="https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/358933/original/file-20200921-20-1gxqvnu.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">
<figcaption>
<span class="caption">Funnel webs are among Australia’s most feared spiders.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Why so deadly?</h2>
<p><a href="https://science.sciencemag.org/content/361/6405/842">About 15%</a> of all animals use venom for reasons such as to kill or immobilise prey, self-defence or to gain advantage over competitors, such as during breeding season. As an animal matures and its activities change, so too can its venom.</p>
<p>Australian funnel webs are among a small group of spiders whose venom can kill humans. However all 13 <a href="https://www.thelancet.com/pdfs/journals/lancet/PIIS0140673610622301.pdf">recorded deaths</a> occurred before anti-venom was introduced in 1981.</p>
<p>Funnel web venom is lethal because it contains a type of neurotoxin called “delta-hexatoxin”. This toxin can kill humans by attacking the nervous system, keeping nerves “turned on” and firing over and over again. In severe cases the venom can cause muscles to go into spasm, blood pressure to drop dangerously, coma and organ failure, and <a href="https://www.thelancet.com/pdfs/journals/lancet/PIIS0140673610622301.pdf">ultimately death</a> – sometimes within a few hours.</p>
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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>
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<p>Scientists have long been puzzled by why these toxins are so deadly to humans, when we and other primates have never been funnel web prey or predator. Scientists were also perplexed as to why male funnel webs appeared to have much deadlier venom than females, and caused most human deaths.</p>
<p>However we did know most funnel web bites in humans occur during the spiders’ <a href="http://britishspiders.org.uk/bulletin/090603.pdf">summer</a> mating season, when the male spiders rarely feed. This suggested the venom played a defensive role. </p>
<figure class="align-center ">
<img alt="Venom dripping from a funnel web's fang" src="https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/358936/original/file-20200921-22-1xrxiix.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">
<figcaption>
<span class="caption">Venom from a male funnel web spider can kill vertebrates, including humans.</span>
<span class="attribution"><span class="source">David Wilson</span></span>
</figcaption>
</figure>
<h2>Spider sleuthing</h2>
<p>We set out to solve this mystery, using molecular analysis of the venom. Although 35 species of Australian funnel-web spiders were officially recognised, only nine delta-hexatoxins from four species had previously been identified. Our analysis increased the number of known delta-hexatoxins to 22, from the venom of ten funnel-web species. </p>
<p>Having this extra data helped us paint a much clearer picture of the venom’s story. It all comes down to natural selection – the process where organisms best adapted to their environment survive and procreate. The genes responsible for this success are preserved and carry on to the next generations, driving the process of evolution</p>
<p>Our data revealed how natural selection triggered a change in the venom of adult male funnel webs. When males sexually mature, they leave the safety of their burrow and wander considerable distances to find a female. This puts male funnel web spiders in the path of vertebrate predators. These can include reptiles (such as lizards or geckos), marsupials (such as antechinus and dunnarts), mammals (such as rats) and birds. </p>
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Read more:
<a href="https://theconversation.com/should-i-kill-spiders-in-my-home-an-entomologist-explains-why-not-to-95912">Should I kill spiders in my home? An entomologist explains why not to</a>
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<p>When funnel-web spiders evolved millions of years ago, toxins in its venom mainly targeted their natural prey: insects such as cockroaches and flies. We examined the genetic sequences of all delta-hexatoxins in funnel web venom. We found over time, the venom of adult males evolved to be potent to vertebrate predators. Unluckily for humans, who are vertebrate animals, we copped it in the process. </p>
<p>Female funnel webs stay safely in their burrows and let the males come to them. So the venom of females is thought to remain potent only against insects their entire lives.</p>
<figure class="align-center ">
<img alt="A funnel web spider entering its burrow" src="https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/358937/original/file-20200921-20-1mo5tad.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">Female funnel webs stay in their burrows, so are less likely to be eaten by predators.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>Take comfort</h2>
<p>Now armed with a stronger understanding of how delta-hexatoxins evolved, we want to put that knowledge to use. The new genetic sequences we discovered will enable a better understanding of what funnel web spider venom does to the human body. This could be critical for improving existing anti-venoms, and for designing evidence-based treatment strategies for bite victims.</p>
<p>We’re not just looking at the venoms of sexually mature males. We’re also examining female funnel-web venom, hoping their insect-specific toxins will lead to new types of insecticides which are <a href="https://www.nationalgeographic.com/news/2014/6/spider-venom-honeybee/">less harmful</a> to non-target insects and the broader environment.</p>
<p>Funnel webs may be one of Australia’s most deadly spiders. But perhaps its some comfort to know their venom is not targeted against us, and the potential lethal effects are just a stroke of evolutionary bad luck.</p>
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<strong>
Read more:
<a href="https://theconversation.com/curious-kids-why-do-spiders-need-so-many-eyes-but-we-only-need-two-116821">Curious Kids: why do spiders need so many eyes but we only need two?</a>
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<img src="https://counter.theconversation.com/content/146406/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Volker Herzig receives funding from the Australian Research Council (FT190100482)</span></em></p><p class="fine-print"><em><span>Bryan G. Fry 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>Funnel webs are considered one of Australia’s most fearsome spiders, but their ability to kill humans is by accident rather than design.Bryan G. Fry, Associate Professor, School of Biological Sciences, The University of QueenslandVolker Herzig, Associate Professor, University of the Sunshine CoastLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/509632016-01-10T19:16:23Z2016-01-10T19:16:23ZAre Australian snakes the deadliest in the world? Not even close<figure><img src="https://images.theconversation.com/files/107486/original/image-20160107-14020-5z2o2c.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is Australia really the most lethal nation on earth when it comes down to it?</span> <span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Many Australians pride themselves on the belief that, of all the countries in the world, their snakes, spiders, jellyfish, centipedes, fish, ticks, bees and ants are the worst. And it’s easy to believe they’re right.</p>
<p>After all, there’s <a href="http://www.ncbi.nlm.nih.gov/pubmed/524395">a 37-year-old list</a> that says that 21 of the 25 most toxic snakes in the world are all from Australia. And aren’t funnel-web spiders, box jellyfish, stonefish and cone snails all dead-set killers? </p>
<p>But is Australia really the most lethal nation on earth when it comes down to it? Actually, no, it’s not. And the reason is simple. </p>
<h2>A matter of perspective</h2>
<p>It’s useless to measure how dangerous something is based solely on laboratory lethality tests. Venom toxicity and the number of mice killed with a snake’s average venom yield, for instance, are interesting only from an academic perspective. </p>
<p>If you happen to be one of <a href="https://en.wikipedia.org/wiki/Epidemiology_of_snakebites">around 100,000 people</a> who die of snake bites around the world in any given year, such facts are irrelevant. The same goes for just about any other venomous creature we might like to proudly declare as the planet’s most lethal. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/107332/original/image-20160105-28969-1l0pl0j.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 Eastern Brown Snake (<em>Pseudonaja textilis</em>) and its relatives cause most of the bites and fatalities in Australia.</span>
<span class="attribution"><span class="source">David Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>While Australia has spiders, jellyfish and other animals with lethal venom, the reality is that bites and deaths are rare. In other words, despite very toxic venoms, these creatures don’t bite enough people to cause major problems. Even when they do bite, it’s rare for snakes to inject venom (or “envenom”), less than 450 of 3,000 snakebite cases a year, for example. Death is even rarer (two to three cases a year). </p>
<p>Animals that cause the greatest burden of human suffering and death are the ones we need to be most worried about, and from that perspective, the most dangerous are not Australian. </p>
<p>Consider snakes, one of the most feared groups of venomous animals in the world. If we want to know which snakes are the most dangerous, we should consider the global, rather than individual impact. That view shows three groups of vipers that collectively span almost all of the tropical developing world – and have a huge impact on human health – best deserve the title of <em>the world’s most dangerous</em>.</p>
<h2>Meet the carpet viper</h2>
<p>Perhaps the most dangerous of these three genera is a diverse group of small, seemingly innocuous vipers that range from Sri Lanka and India, across the Middle East and through a huge part of the northern half of Africa. </p>
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<img alt="" src="https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/105364/original/image-20151211-8297-39c4q6.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">West African carpet viper (<em>Echis ocellatus</em>) from Togo – member of a genus of small vipers that are the world’s most dangerous snakes.</span>
<span class="attribution"><span class="source">David Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>These snakes got their name from the patterns that adorn their bodies. They are small- to medium-sized vipers believed to injure and kill more people each year than any other species in the world. Yet they don’t make the list of most toxic snakes mentioned above at all. </p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/22851309">In just one hospital</a> in Nigeria’s north-eastern Gombe State, 5,367 victims of carpet viper envenoming were treated over a two-year period. But for the use of an effective antivenom, the fatality rate may have been as high as 35% to 45%. That’s more cases at one hospital in two years than all the recorded cases throughout Australia in ten. </p>
<p>Their huge range across a vast swathe of the rural tropics brings carpet vipers into contact with hundreds of thousands of people each year. And while nobody has a tally of just how many lives they affect, international experts all agree that when it comes to the most dangerous snake, these vipers have no competition. </p>
<h2>Russell’s viper</h2>
<p>In Pakistan, India and Sri Lanka, carpet vipers give way to the larger Russell’s viper (<em>Daboia russelii</em>). </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/105363/original/image-20151211-8314-1qqw4l0.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 Russell’s viper (<em>Daboia russelii</em>) arguably the most dangerous snake in Asia with a potent cocktail of destructive toxins in its venom.</span>
<span class="attribution"><span class="source">David Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This pugnacious viper lurks in fields, rice paddies and farmland from Pakistan through India, Nepal, Sri Lanka, Bangladesh, Myanmar, Thailand and Cambodia, as well as Taiwan and southern China. There’s a distinct, disjoined population of an equally dangerous sister species (<em>Daboia siamensis</em>) in eastern Java and the lesser Sundas in Indonesia.</p>
<p>Like the victims of carpet vipers, those bitten by these snakes bleed uncontrollably and often fatally. At the same time, local tissue destruction and necrosis, acute kidney injury, neurotoxic paralysis, shock, and cardiac arrhythmia can produce a terrifying clinical picture that can very quickly lead to death. </p>
<h2>Lancehead pit vipers</h2>
<p>Latin America, from Mexico to Argentina, is home to more than 40 species in the genus <em>Bothrops</em>, lancehead pit vipers. Collectively, this very diverse group is responsible for many of the estimated 150,000 or more cases of venomous snakebites in Central and South America each year. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/105369/original/image-20151211-8329-fhie1h.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">Venezuelan lancehead (<em>Bothrops venezuelensis</em>) one of a large, widely distributed genus of dangerous pit vipers that cause enormous misery in Latin America.</span>
<span class="attribution"><span class="source">David Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Lancehead bites produce devastating local tissue injury with oedema (or fluid retention), bruising, skin and muscle necrosis and fluid-filled blisters. Permanent disability including amputation is common. </p>
<p>Systemic effects involving stopping the ability of blood to clot, platelet destruction, shock, acute kidney injury and thrombosis present doctors with a complex medical emergency that – even with the best care available in a modern hospital – can still ultimately prove fatal. </p>
<p>Since many cases occur in rural areas, away from good medical care, poor outcomes are common.</p>
<p>Within Australia, the low mortality from snakebite (and other types of venomous injury) is very much the product of decades of research and excellent clinical care, not to mention safe and effective antivenoms. </p>
<p>It’s the lack of these same attributes elsewhere in the world that renders snakebites such a potentially life-changing (if not, life-ending) public health issue. </p>
<p><em>This article is part of our series <a href="https://theconversation.com/au/topics/deadly-australia">Deadly Australia</a>. Stay tuned for more pieces on the topic in the coming days.</em></p>
<hr>
<p><em>David will be on hand for an Author Q&A between 11am and noon AEDT on Tuesday, January 12, 2016. Post your questions in the comments section below.</em></p><img src="https://counter.theconversation.com/content/50963/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Williams receives funding from CSL Limited, the National Health and Medical Research Council and the government of Papua New Guinea. He is affiliated with the Global Snakebite Initiative Limited, a not-for-profit advocacy organization, and is an employee of the University of Melbourne. </span></em></p>There’s a simple reason why Australia isn’t the most lethal nation in the world.David Williams, Head, Charles Campbell Toxinology Centre at the University of Papua New Guinea & Australian Venom Research Unit, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/510482016-01-10T19:15:54Z2016-01-10T19:15:54ZSpiders are a treasure trove of scientific wonder<figure><img src="https://images.theconversation.com/files/107496/original/image-20160107-13986-17lmrv2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">As a generalist predator, spiders, like this Western Rough Wolf Spider, help limit the number of insects in your garden.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/jean_hort/4521389919/">Jean and Fred/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Australia has an incredible diversity of native spiders, including the <a href="https://theconversation.com/health-check-what-should-you-do-if-youre-bitten-by-a-spider-49232">potentially lethal</a> funnel-web, the ubiquitous huntsman, and the charming peacock spider. Only two can be deadly for humans – the funnel-web and redback spiders – and we have antivenom for both.</p>
<p>Found all across the country, spiders play an important role in the environment as generalist predators. Increasingly, their venom is being used <a href="http://www.tandfonline.com/doi/abs/10.1517/14712598.2011.621940#.Vl4bD2QrIsk">to develop novel human therapeutics</a> and <a href="http://www.mdpi.com/2072-6651/4/3/191">to create new, selective, sustainable insecticides</a>.</p>
<h2>A model citizen</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1031&fit=crop&dpr=1 600w, https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1031&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1031&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1296&fit=crop&dpr=1 754w, https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1296&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/107499/original/image-20160107-13988-emlng8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1296&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">How house spider webs change when the spider is exposed to different chemicals.</span>
</figcaption>
</figure>
<p>Spiders are often a starting point for children to fall in love with the natural world: they’re found almost everywhere, and everyone can appreciate their tremendous diversity. What’s more, scientists are constantly learning new things from them.</p>
<p>They’re an important model system to help us understand the basics of biology. We know that the spider and its web are so closely tied that exposure to different chemicals has <a href="http://ntrs.nasa.gov/search.jsp?R=19950065352">specific effects on how the webs are spun</a>. </p>
<p>Other research suggests the blue colour in tarantulas evolved independently <a href="http://advances.sciencemag.org/content/1/10/e1500709.full">at least eight times</a>. This may help inform our understanding of the evolution of colouration, as well as how to make better paints.</p>
<p>The peacock spider <a href="http://rspb.royalsocietypublishing.org/content/282/1820/20152222">has helped show</a> that strong sexual selection by females depends on a variety of factors. Scientists think <a href="http://www.nature.com/scitable/knowledge/library/sexual-selection-13255240">sexual selection</a> has had an impact on the striking coloration and complex signalling of this spider species, but this is the first evidence to definitively demonstrate female preference has played a role.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OOmUBuaMjzw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Dance, dance revolution.</span></figcaption>
</figure>
<h2>With great power…</h2>
<p>As a generalist predator, <a href="http://www.annualreviews.org/doi/abs/10.1146/annurev.ento.47.091201.145240">spiders help limit</a> the number of insects in your garden. Although they’ll probably eat some good bugs as well as bad while they’re at it.</p>
<p>Spider venom is a complex chemical cocktail of hundreds of different components, and each type has its own very specific activity. Many individual venom components act on the insect nervous system and these can be very useful for scientific research. </p>
<p>My work, for instance, is on discovering newenvironmentally friendly <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0073136">insecticides from spider venoms</a>. Since insect nervous systems are very different from the one found in vertebrates (including humans), individual toxins are frequently active in insects but not in vertebrates, and vice versa. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106386/original/image-20151216-30079-44o3x0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Chemistry of Spider Venom.</span>
<span class="attribution"><a class="source" href="http://www.compoundchem.com/2015/05/21/spider-venom/">Compound Interest</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>When we look for good insecticidal candidates <a href="http://www.ncbi.nlm.nih.gov/pubmed/10881200">we screen for</a> compounds with specific activity in insects and the absence of activity in vertebrates. It’s that specificity that makes spider venoms such powerful sources of new, sustainable insecticides, as well as excellent therapeutics.</p>
<h2>What’s in a venom?</h2>
<p>Spider venoms generally consist of three types of components: small components (salts, carbohydrates, amines and acids to name a few); peptides (small proteins that are generally highly structured); and enzymes (used for digesting food).</p>
<p>If you <a href="https://theconversation.com/health-check-what-should-you-do-if-youre-bitten-by-a-spider-49232">get bitten by a spider</a>, do your best to remain calm, and proceed directly to a medical professional so your symptoms can be monitored and treated. They will administer the appropriate antivenom if required.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=577&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=577&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=577&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=725&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=725&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106207/original/image-20151216-25600-14x8czz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=725&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">The Conversation</span></span>
</figcaption>
</figure>
<p>Spiders deliver venom by injection, using mouth parts called <a href="https://en.wikipedia.org/wiki/Chelicerae">chelicerae</a>, which are informally known as fangs. The chelicerae are found on the front body segment, the cephalothorax, and that’s also where its eight legs are attached. </p>
<p>The abdomen is the other spider body segment, and that’s where the spinnerets, used to weave the web, are found.</p>
<p>Spiders sometimes appear hairy, but those are actually <a href="https://en.wikipedia.org/wiki/Seta">sensory setae</a> that are used to collect detailed information about the nearby environment. Depending on the spider species that could include temperature, humidity, and wind direction, and chemical information, such as the source of pheromones used in mating.</p>
<p>So leave your fear behind and go ahead, embrace the majesty of spiders. But pick your species carefully – <a href="http://www.abc.net.au/news/2015-11-27/police-respond-to-domestic-after-man-screams-over-spider/6979724">and try not to get the police involved</a>.</p>
<p><em>This article is part of our series <a href="https://theconversation.com/au/topics/deadly-australia">Deadly Australia</a>. Stay tuned for more pieces on the topic in the coming days.</em></p><img src="https://counter.theconversation.com/content/51048/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Maggie Hardy receives funding from The University of Queensland and UniQuest Pty Ltd.</span></em></p>Only two Australian spiders can kill you, but the rest are a pretty fascinating bunch.Maggie Hardy, Postdoctoral Research Fellow, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/492322015-10-26T05:11:52Z2015-10-26T05:11:52ZHealth Check: what should you do if you’re bitten by a spider?<figure><img src="https://images.theconversation.com/files/98720/original/image-20151017-25138-1uavcra.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Spiders such as this funnel-web (Hadronyche infensa) will only bite if threatened.</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p><em>This article is about spider bites in Australia, but doesn’t constitute medical advice. Always see a medical professional if you believe you’ve been bitten or stung by a venomous animal.</em></p>
<p>I work with spiders for a living, and I’ve never been bitten by one.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=628&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=628&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=628&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=789&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=789&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98730/original/image-20151017-25117-zzxdt9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=789&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 author milking a tarantula.</span>
<span class="attribution"><span class="source">@DrMaggieHardy/author provided</span></span>
</figcaption>
</figure>
<p>There are <a href="http://www.wsc.nmbe.ch/">more than 45,000 species of spiders</a>, but only a handful are potentially dangerous to humans. </p>
<p>Only two spiders in Australia are of medical concern: funnel-web spiders (in the family Hexathelidae) and redback spiders (<em>Latrodectus</em>, in the family Theridiidae). </p>
<p>A <a href="https://www.mja.com.au/journal/2003/179/4/white-tail-spider-bite-prospective-study-130-definite-bites-lampona-species?0=ip_login_no_cache%3D71b017124538a7aa5b6e5b2ea8f157c4">review of 130 confirmed white-tail spider bites</a> showed no cases of flesh-eating ulcers or confirmed infections, so those spiders are not considered dangerous to humans.</p>
<p>Most “spider bites” that doctors see are <a href="http://www.sciencedirect.com/science/article/pii/S0736467909007926">actually skin and soft tissue infections</a>. </p>
<p>The myth that spider bites cause secondary infection <a href="http://www.sciencedirect.com/science/article/pii/S004101011400600X">has also been busted</a>, although – as for any wound – disinfecting and cleaning is necessary. </p>
<p>In the course of your life you’ll see many spiders (and there are <a href="http://www.burkemuseum.org/spidermyth/myths/3feet.html">many more</a> you won’t see), but only if they feel threatened will they bite you. Generally a spider tries to warn you, but unfortunately you might not always see (or hear) the spider.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/NlIRJRm64GA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Please, do not do this to your pet tarantula. Most spiders don’t want to bite you.</span></figcaption>
</figure>
<p>Venoms are energetically expensive for the animal to make, and the spider <a href="http://www.sciencedirect.com/science/article/pii/S0041010112008173">doesn’t want to waste venom</a> if it’s not needed for defence or to catch its food. </p>
<p>Funnel-web spider venom is one of the few that is lethal to humans (and other primates). It’s deadly because of a single component (<a href="http://www.arachnoserver.org/toxincard.html?id=307">δ‑hexatoxin‑Hv1a</a>) out of the hundreds of different molecules in the venom.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98733/original/image-20151017-25125-1obmenw.png?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"></a>
<figcaption>
<span class="caption">The three-dimensional structure of the vertebrate-active toxin from funnel-web spider venom. The red lines indicate the molecular bonds that confer extreme stability to the peptide.</span>
<span class="attribution"><span class="source">@DrMaggieHardy using PDB structure/author provided</span></span>
</figcaption>
</figure>
<p>Redback spiders are the most commonly encountered spider of medical concern, but <a href="http://www.toxinology.com/generic_static_files/cslavh_antivenom_redback.html">less than 20% of all bites</a> cause significant medical symptoms. While unpleasant, the symptoms (which may include muscle pain, vomiting and sweating within 12 to 24 hours) are generally <a href="http://www.sciencedirect.com/science/article/pii/S0140673610622301">not lethal</a>. </p>
<p>Bites from funnel-web spiders are also rare and, again, the amount of venom injected is not always enough to cause significant medical symptoms. </p>
<p>After the antivenom was created in the early 1980s, recovery from nonfatal bites changed from several weeks to <a href="http://www.ncbi.nlm.nih.gov/pubmed/6503783?dopt=Abstract">one to three days</a>, and no one has died since. </p>
<p>Symptoms of exposure to a lethal dose of funnel-web spider venom include tingling around the lips, tongue twitching, salivation and muscle spasms, which may lead to convulsions. Subsequent high blood pressure, rapid heartbeat and respiratory distress are why the venom is potentially lethal. </p>
<p>When a funnel-web injects a lethal amount of venom, without the antivenom, <a href="http://www.toxinology.com/generic_static_files/cslavh_antivenom_funweb.html">death can occur within an hour</a>. </p>
<h2>Know your spiders</h2>
<p>Tarantulas can climb glass and plastic; funnel-web spiders cannot. Funnel-web spiders have a classic strike pose to threaten off predators, in which they rear up on their back legs.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/a-dGVqqN6i8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The author, milking a funnel-web spider. This spider is being handled by an expert for research purposes; do not try this at home.</span></figcaption>
</figure>
<p>Despite the distinctive look of a funnel-web spider, a number of spiders look similar. Male and female funnel-web spiders are large (on average body length of one to five centimetres), with a brown or black body. The front of the body is glossy and may be covered in some dark hairs; the spinnerets at the back of the abdomen are easily visible. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=441&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=441&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=441&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=554&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=554&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98731/original/image-20151017-25112-10blplx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=554&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">All these spiders are potentially dangerous, but only two are funnel-web spiders. Clockwise from top left: male Sydney funnel-web spider (<em>Atrax robustus</em>); male mouse spider (<em>Missulena bradleyi</em>); female mouse spider (<em>Missulena</em> spp), and female Blue Mountains funnel-web spider (<em>Hadronyche versuta</em>).</span>
<span class="attribution"><span class="source">Photos from the Australian Museum.</span></span>
</figcaption>
</figure>
<p>Redback spiders are small (1cm for females, 0.4cm for males), and are black or sometimes brownish in colour. Females have an obvious orange or red stripe (which may be vaguely hourglass) on the underside of the abdomen. Males have similar, but less distinct, markings.</p>
<h2>Step 1: Don’t panic</h2>
<p>If a spider bites you, keep a cool head. Treat each bite as though it could be deadly, since it takes an expert to tell a funnel-web spider from any of the other large, black spiders found in Australia. </p>
<p>See a medical professional immediately if you think you may have been bitten.</p>
<p>For funnel-web and mouse spider bites, experts <a href="http://www.sciencedirect.com/science/article/pii/S0041010199001713">recommend</a> using a <a href="https://en.wikipedia.org/wiki/Pressure_immobilisation_technique">pressure-immobilisation bandage</a> before seeking medical help, to slow the progress of venom into your circulatory system and around the body. </p>
<p>Proceed immediately to a medical professional who can monitor your symptoms and determine whether the antivenom is required (most hospitals stock it).</p>
<p>There is no proven first aid treatment for redback spider bites. However, according to Associate Professor Julian White, a clinical spider bite expert at the Women’s and Children’s Hospital in North Adelaide, the immobilisation method is not appropriate for redback spider bites. </p>
<p>You should go immediately to a medical professional who can monitor your symptoms and determine whether the antivenom is necessary.</p>
<h2>Step 2: What bit you?</h2>
<p>If it’s safe to, collect the spider. If you don’t want to collect it, try to get a clear photo of the spider’s face, and another of its body from above; try to realistically remember the size of the spider.</p>
<p>Not all spiders live everywhere, so an expert is needed to identify which spider you’ve encountered. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=222&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=222&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=222&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=279&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=279&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98734/original/image-20151017-25112-1ug0uha.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=279&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Occurrence record map of funnel-webs (left, spiders from the family Hexathelidae) and redbacks (right, spiders in the genus <em>Latrodectus</em>).</span>
<span class="attribution"><span class="source">Maps from the Atlas of Living Australia.</span></span>
</figcaption>
</figure>
<p>Once experts identify which spider is responsible for the bite, doctors can determine what treatment is needed.</p>
<h2>Step 3: Treatment</h2>
<p>Spider venoms are complex chemical cocktails consisting of hundreds of different components. Each component has a unique role to play in the venom, and the activity of each individual component is very specific. </p>
<p>The individual components in spider venoms that are responsible for most of the activity are small proteins, or peptides, that contain a specific, highly structured three-dimensional scaffolding. We call those structured peptides toxins.</p>
<p>Antivenom is designed to neutralise the individual venom components that are dangerous. The <a href="http://www.csl.com.au/docs/822/652/Funnel%20Web%20Spider%20AV%20PI%20V6%20clean%20TGA%20approved%2018%20Sept%202013.pdf">antivenom</a> consists of purified immunoglobulins, which bind the venom toxins while they circulate in your blood. </p>
<p>Because the antivenom is designed to bind the toxins, not to treat by age or weight, the amount administered <a href="http://jnnp.bmj.com/content/75/suppl_3/iii40.full">will be the same</a> regardless of the size or age of the patient. </p>
<h2>Be prepared</h2>
<p>Try to avoid being bitten in the first place. In the case of redbacks, learn to recognise and avoid their <a href="http://australianmuseum.net.au/redback-spider">distinct webs</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/tvjhc6BXQDM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This video outlines the finer points of redback spider web design.</span></figcaption>
</figure>
<p>In the case of funnel-web spiders, be alert during their mating season (November to February) when males are likely to be out of their burrows. Their burrows also have a distinctive web, and generally you’ll be able to detect a funnel shape in the above-ground part of the web.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98732/original/image-20151017-25112-s475un.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">A funnel-web spider burrow on Fraser Island.</span>
<span class="attribution"><span class="source">@DrMaggieHardy/author provided</span></span>
</figcaption>
</figure>
<p>If you are planning a trip and are concerned you’ll be in the same environment as these beautiful and rare animals, consider completing <a href="https://training.gov.au/Training/Details/HLTFA302B">a first aid course for remote situations</a>.</p>
<p><em>For more information about spider bites and clinical toxicology, visit <a href="http://www.toxinology.com">www.toxinology.com</a>.</em></p><img src="https://counter.theconversation.com/content/49232/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Maggie Hardy receives funding from The University of Queensland and UniQuest Pty Ltd.</span></em></p>There are more than 45,000 species of spider, but only a handful are potentially dangerous to humans.Maggie Hardy, Postdoctoral Research Fellow, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.