tag:theconversation.com,2011:/us/topics/new-guinea-37343/articlesNew Guinea – The Conversation2022-09-02T21:45:34Ztag:theconversation.com,2011:article/1897932022-09-02T21:45:34Z2022-09-02T21:45:34Z‘Impressive rafting skills’: the 8-million-year old origin story of how rodents colonised Australia<figure><img src="https://images.theconversation.com/files/482410/original/file-20220902-18492-69v2n4.jpg?ixlib=rb-1.1.0&rect=14%2C5%2C1902%2C1270&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A hopping mouse from the arid desert of Australia (Notomys). Hopping mice have evolved highly efficient kidneys to deal with the low water environments of Australia's deserts.</span> <span class="attribution"><span class="source">David Paul/Museums Victoria</span></span></figcaption></figure><p>A single, pregnant rodent floating on driftwood across the treacherous waters between Asia and New Guinea 8.5 million years ago may be behind the eventual colonisation of native rodents in Australia, our <a href="https://www.sciencedirect.com/science/article/pii/S0960982222012982?dgcid=author">new research</a> suggests.</p>
<p>Today, Australia has more than 60 species of native rodents found nowhere else in the world. When you count their close relatives across New Guinea and island neighbours, there are over 150 species. These include the rakali, an otter-like rodent with webbed feet, and desert hopping mice that get around like tiny kangaroos.</p>
<p>Until now, we’ve had an incomplete picture of how there came to be so many species. Our new research unites genomic sequencing and museum collections to reconstruct the evolutionary tale of native rodents, including many extinct and elusive species – and they have a fascinating origin story. </p>
<p>Native rodents have also suffered the highest rate of recent extinction of any mammal group in Australia, with 11 mainland species declared extinct since European colonisation in 1788. Many surviving native rodents remain at serious risk of extinction, with urgent conservation action needed to secure their future.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482404/original/file-20220901-9301-psbzi8.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 semi-aquatic rakali (<em>Hydromys chrysogaster</em>) is a native rodent distributed across New Guinea and Australia. Rakali are part of the Hydromys Division, a group that has colonised Australia from New Guinea at least twice in the last million years.</span>
<span class="attribution"><span class="source">David Paul/Museums Victoria</span></span>
</figcaption>
</figure>
<h2>New methods, old specimens</h2>
<p>We extracted and sequenced DNA from museum specimens collected up to 180 years ago to unlock the secrets of the most elusive species. </p>
<p>In one case, we sequenced DNA from a specimen of Guadalcanal rat from the Solomon Islands collected over 130 years ago. The Guadalcanal rat was last seen alive when these specimens were collected in the 1880s, and hasn’t been recorded since. </p>
<p>It’s listed as <a href="https://www.iucnredlist.org/species/22805/22446647">critically endangered</a>, and is very possibly already extinct. </p>
<p>Like the Guadalcanal rat, every single specimen we studied has its own fascinating history. Together, they tell an 8-million-year long evolutionary story.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482407/original/file-20220902-16-7j7ogo.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">This is a specimen of Gould’s mouse from the Natural History Museum in London.</span>
<span class="attribution"><span class="source">Trustees of the Natural History Museum London/C. Ching</span></span>
</figcaption>
</figure>
<p>The genetic relatedness of distant rodent relatives tells us the ancestor of Australia’s native rodents originated in southeast Asia. There’s never been a land connection between Asia and New Guinea, and so we know this must happened via over-water colonisation – possibly on a piece of driftwood.</p>
<p>Our research dates this event to around 8.5 million years ago. Both New Guinea and Australia looked very different back then.</p>
<p>In contrast to the large and high-elevation island of modern New Guinea, 8.5 million years ago it was likely made up of a series of smaller, disconnected islands.</p>
<p>Our results show the earliest arriving rodent ancestors, probably tropical forest specialists, initially spread across this earlier New Guinea. But they then stayed put for 3.5 million years.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/this-adorable-mouse-was-considered-extinct-for-over-100-years-until-we-found-it-hiding-in-plain-sight-160930">This adorable mouse was considered extinct for over 100 years — until we found it hiding in plain sight</a>
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</em>
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<h2>A shared evolutionary story</h2>
<p>Around 5 million years ago, New Guinea experienced a big geological change. Tectonic activity triggered the uplift of an impressive mountain range through the centre of New Guinea, and led to the formation of expansive lowlands. </p>
<p>This expansion opened new environments for rodents to adapt to, and increased connectivity between New Guinea, Australia, and neighbouring islands.</p>
<p>From there, things really took off.</p>
<p>Rodent ancestors first arrived from New Guinea into Australia around 5 million years ago, probably via a land bridge exposed during a period of low sea level.</p>
<p>In Australia, they have adapted to many new environments including the harsh arid desert. In the last few million years, rodents have been especially mobile – repeatedly moving between New Guinea, Australia and neighbouring island archipelagos, generating many new species in the process.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=456&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=456&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=456&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=574&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=574&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482406/original/file-20220902-17818-9rbk6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=574&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Native rodents first arrived to New Guinea from Asia 8.5 million years ago, and then arrived to Australia 5 million years ago. Over the past few million years, they also have spread across the Solomon and Maluku Island archipelagos.</span>
</figcaption>
</figure>
<p>In our region alone rodents have transitioned between different geographic areas or islands at least 24 independent times in the past 5 million years. </p>
<p>Quite often, this has happened via over-water colonisation. Just like their ancestor, who crossed the waters from southeast Asia 8.5 million years ago, native rodents have continued to leverage their impressive rafting skills.</p>
<p>And yet, despite this remarkable flexibility across evolutionary time, native rodents have not been able to tolerate the dramatic changes to their environment that have occurred in the past 200 years. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-epic-550-million-year-story-of-ulu-u-and-the-spectacular-forces-that-led-to-its-formation-167040">The epic, 550-million-year story of Uluṟu, and the spectacular forces that led to its formation</a>
</strong>
</em>
</p>
<hr>
<h2>Protecting native rodents</h2>
<p>Since 1788, we’ve lost 11 native rodent species to extinction. These include the <a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=131">white-footed rabbit-rat</a> and the <a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=136">lesser stick-nest rat</a>, once common on the Australian landscape.</p>
<p>Native rodents are particularly susceptible to predation by feral cats and foxes, land clearing, competition with pest rodents, and introduced disease. These ongoing threats place surviving species at serious risk of extinction. </p>
<p>One of Australia’s most critically endangered mammals, the central rock-rat, is on the brink of extinction after extensive habitat loss and predation by cats and foxes. <a href="https://www.australianwildlife.org/central-rock-rat-australias-most-endangered-mammal-airlifted-to-safe-refuge/">Captive breeding programs</a> are underway to boost population numbers.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482405/original/file-20220901-18063-yco9vc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=524&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A smoky mouse (<em>Pseudomys fumeus</em>) in the Grampians-Gariwerd National Park, Victoria, Australia. The smoky mouse is part of an evolutionary group that originated after colonisation of Australia from New Guinea around 5 million years ago, and is currently endangered after suffering population declines.</span>
<span class="attribution"><span class="source">David Paul/Museums Victoria</span></span>
</figcaption>
</figure>
<p>We know even less about the conservation status of many species in New Guinea, the Solomon Islands and Maluku Islands. </p>
<p>By combining genetic data from both modern and historical specimens, our <a href="https://doi.org/10.1016/j.cub.2022.08.021">new research</a> takes stock of the diversity of native rodents, and will help to define and prioritise species for conservation efforts.</p>
<p>By understanding how our native rodents evolved, we can make more informed decisions about how best to protect them into the future. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/death-by-irony-the-mystery-of-the-mouse-that-died-of-smoke-inhalation-but-went-nowhere-near-a-fire-139906">'Death by irony': The mystery of the mouse that died of smoke inhalation, but went nowhere near a fire</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/189793/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emily Roycroft receives funding from the Australian Government Research Training Program, the Dame Margaret Blackwood Soroptimist Scholarship, the Alfred Nicholas Fellowship (University of Melbourne), and the Holsworth Wildlife Research Endowment. This project received funding from Bioplatforms Australia through the Australian Government National Collaborative Research Infrastructure Strategy, via the Oz Mammals Genomics Initiative.</span></em></p>Australia has more than 60 species of native rodents found nowhere else in the world. New research used museum specimens to find out how they got here.Emily Roycroft, Postdoctoral Research Fellow, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1442792020-08-12T05:38:14Z2020-08-12T05:38:14Z‘Majestic, stunning, intriguing and bizarre’: New Guinea has 13,634 species of plants, and these are some of our favourites<figure><img src="https://images.theconversation.com/files/352413/original/file-20200812-22-1pqsmht.JPG?ixlib=rb-1.1.0&rect=20%2C190%2C2285%2C2659&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">_Bulbophyllum alkmaarense_: New Guinea is home to more than 2,400 species of native orchids. </span> <span class="attribution"><span class="source">Andre Schuiteman/CSIRO</span></span></figcaption></figure><p>Scientists have been interested in the flora of New Guinea <a href="https://doi.org/10.1007/978-94-009-8632-9_6">since the 17th century</a>, but formal knowledge of the tropical island’s diversity has remained limited. </p>
<p>To solve this mystery, our global team of 99 scientists from 56 institutions built the first ever <a href="https://doi.org/10.1038/s41586-020-2549-5">expert-verified checklist</a> to the region’s vascular plants (those with conductive tissue). </p>
<p>We found there are 13,634 formally described species of plants in New Guinea, of which a remarkable 68% are known to occur there and nowhere else. This richness trumps both Madagascar (11,488 species) and Borneo (11,165 species), making New Guinea the most floristically diverse island in the world.</p>
<p>From tarantula-like orchids to giant bananas, here we reveal some of the more mysterious plants on our checklist. Sadly, unsustainable <a href="https://www.globalforestwatch.org/map/country/PNG">logging</a> and climate change threaten the conservation of many New Guinean species, and we highlight urgent solutions. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/people-are-blind-to-plants-and-thats-bad-news-for-conservation-65240">People are 'blind' to plants, and that's bad news for conservation</a>
</strong>
</em>
</p>
<hr>
<h2>The majestic flora of New Guinea</h2>
<p>New Guinea is a land of evocative contrasts. As the world’s largest tropical island – made up of Papua New Guinea to the east and two Indonesian provinces to the west - its biological diversity spans habitats from fringing mangroves to alpine grasslands.</p>
<p>The flora is diverse, filled with the majestic, stunning, intriguing and bizarre. However, very little is known about the conservation status of many species in New Guinea, which remains relatively unexplored by scientists.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The high hoop pine with thin branches and a full canopy" src="https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352408/original/file-20200812-20-2skcei.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">High hoop pines tower over forest canopy.</span>
<span class="attribution"><span class="source">Wikimedia</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>There are the few remaining forests of 60 metres high hoop pine (<em>Araucaria cunninghamii</em>) and klinkii pine (<em>A. hunsteinii</em>), that <a href="http://hdl.handle.net/1885/144171">tower majestically</a> up to 30 metres above the already tall rainforest canopy. </p>
<p>Figs, with their copious sap, are present in diverse forms, from small shrubs to vines, or large canopy trees. </p>
<p>And the strongly <a href="http://portal.cybertaxonomy.org/flora-malesiana/cdm_dataportal/taxon/0f15a365-6d57-49dd-99ab-28a6a4be28f0#uses">irritant black sap</a> of the Semecarpus tree, a distant relative of the American poison ivy, causing severe dermatitis, is something naive botanists must learn to avoid! </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Three panels showing different parts of Ryparosa amplifolia" src="https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=191&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=191&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=191&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=241&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=241&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352437/original/file-20200812-20-1k5jok3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=241&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Ryparosa amplifolia</em> maintains an intimate association with ants via hollow stems and food bodies.</span>
<span class="attribution"><span class="source">Bruce Webber</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Then there’s the <em>Ryparosa amplifolia</em>, a rainforest tree that provides <a href="https://doi.org/10.1111/j.1095-8339.2007.00651.x">swollen hollow stems</a> for ant colonies to live inside. The tree also produces energy rich “food bodies” – granule-like structures on the leaves that mimic animal tissue and provide the ants with sustenance. In return, the ants act as bodyguards, chasing away insect herbivores, and leaf cleaners.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A giant banana tree with an umbrella-like canopy and a thick trunk towers in a rainforest" src="https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1067&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1067&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1067&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352410/original/file-20200812-24-h9stei.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1340&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 giant banana tree holds the record of being the largest and tallest non-woody plant in the world.</span>
<span class="attribution"><span class="source">Rodrigo Camara</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Some of our most popular foods were <a href="https://doi.org/10.1086/658682">domesticated from New Guinea</a>, including sugarcane and bananas. But the giant banana, <em>Musa ingens</em> is a a highlight in montane forests. Its leaves can stretch to a length of 5 metres, the tree can grow more than 20 metres tall, and its fruits are massive.</p>
<p>With more than 2,400 species of native orchid species, New Guinea is one of the most spectacular floral gardens in the world. It includes fascinating species such as <em><a href="https://doi.org/10.1111/j.1095-8339.2011.01183.x">Bulbophyllum nocturnum</a></em>, which is the first and only known example of a night-flowering orchid, and <a href="http://www.orchidsnewguinea.com/orchid-information/species/speciescode/547"><em>Bulbophyllum tarantula</em></a>, with appendages that resemble the iconic spider.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of a green orchid with pink blotches and furry leg-like bits " src="https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1110&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1110&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1110&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1395&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1395&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352412/original/file-20200812-24-1u8j6l0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1395&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Bulbophyllum tarantula</em> gets its name from its tarantula-like appearance.</span>
<span class="attribution"><span class="source">Jan Meijvogel</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>An uncertain future</h2>
<p>Despite New Guinea’s seemingly high number of plant species, at least 3,000 species remain to be discovered and formally described. This estimate is based on the rate of description of new species in the past decades.</p>
<p>Much of New Guinea, particularly the Indonesian part, has been extremely poorly studied, with very few plant species collected. Even within Papua New Guinea, the distribution of many species is inadequately known. This means our findings should be viewed as <a href="https://doi.org/10.1111/ecog.04481">a baseline</a> upon which to prioritise further work.</p>
<p>The biggest impact on forest conservation is from <a href="https://doi.org/10.1016/j.biocon.2018.04.029">logging</a>, both clear-felling and degradation. As land is predominantly under customary ownership, addressing subsistence-related forest loss is a long-term challenge. <a href="https://advances.sciencemag.org/content/5/11/eaaz1455.full">Climate change</a> adds yet further threats, including increased burning of degraded forest due to drier weather. </p>
<p>This means there’s a high risk of the world losing entire species before they are even known.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Looking down on the jungles of Papua New Guinea" src="https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352399/original/file-20200812-21-1v92v26.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">Unsustainable logging and climate change are the biggest threats to the flora of New Guinea.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>To this end, in 2018 the governors of Indonesia’s two New Guinea provinces announced the <a href="http://journal.unhas.ac.id/index.php/fs/article/view/6067">Manokwari Declaration</a>, a pledge to conserve 70% of forest cover for the western half of the island.</p>
<h2>Reversing funding shortfalls and declining engagement</h2>
<p>Our work builds on many decades of effort by plant collectors whose countless nights under leaking canvas, grass huts and bark shelters have led to thousands of plant discoveries.</p>
<p>Their stories are astounding. These fearless adventurers have sampled water plants by jumping from helicopters hovering low over Lake Tebera, swam in the Purari River rapids to haul a disabled dugout canoe full of botanists and cargo to safety, and have fallen into beds of stinging plants in the mountains of Wagau without subsequent access to pain relief. </p>
<p>Taxonomy – the discipline of identifying, classifying, and understanding relationships between plants – is the key to unlocking the value of this collecting effort. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="
A yellow flower with small brown spots and three appendages" src="https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=610&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=610&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=610&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=766&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=766&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352416/original/file-20200812-19-sse1m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=766&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Bulbophyllum nocturnum</em>: the first known example of an orchid species in which flowers open after dark and close in the morning.</span>
<span class="attribution"><span class="source">Jan Meijvogel</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But the discipline is <a href="https://www.science.org.au/support/analysis/decadal-plans-science/discovering-biodiversity-decadal-plan-taxonomy">suffering</a> from global <a href="https://www.nature.com/news/uk-government-slammed-for-kew-gardens-budget-crunch-1.17045">funding shortfalls</a> and declining engagement. For instance, 40% of our co-authors on this work are 55 years or older. </p>
<p>Future opportunities for botanical research with local New Guineans at the helm is also vital – only 15% of the scientific publications on the New Guinean flora over the past 10 years <a href="https://doi.org/10.1038/d41586-020-02225-4">involved local co-authors</a>. </p>
<p>Improved collaboration between taxonomists, scientific institutions, governments and New Guinean scientific agencies could address these critical urgent priorities.</p>
<p>Undoubtedly, the conservation of New Guinea’s unique flora will be challenging and require work on many fronts that transcend single disciplines or institutions. From what we know already, a world of botanical surprises awaits in the last unknown.</p>
<p>After all, as 19th century naturalist J.B. Jukes <a href="https://www.jstor.org/stable/j.ctt1d10hn9.14?seq=1#metadata_info_tab_contents">wrote</a>: </p>
<blockquote>
<p>I know of no part of the world, the exploration of which is so flattering to the imagination, so likely to be fruitful in interesting results […] and altogether so well calculated to gratify the enlightened curiosity of an adventurous explorer, as the interior of New Guinea.</p>
</blockquote>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-superheroes-to-the-clitoris-5-scientists-tell-the-stories-behind-these-species-names-142922">From superheroes to the clitoris: 5 scientists tell the stories behind these species names</a>
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<img src="https://counter.theconversation.com/content/144279/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bruce Webber receives funding from CSIRO. </span></em></p><p class="fine-print"><em><span>Barry J Conn and Rodrigo Cámara-Leret 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>With tarantula-like orchids and giant bananas, New Guinea is officially the most floristically diverse island in the world.Bruce Webber, Principal Research Scientist, CSIROBarry J Conn, Researcher, University of SydneyRodrigo Cámara-Leret, Researcher, University of ZurichLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1178422019-06-03T20:10:26Z2019-06-03T20:10:26ZA deadly fungus threatens to wipe out 100 frog species – here’s how it can be stopped<p>What would the world be like without frogs? Earth is in its <a href="https://science.sciencemag.org/content/360/6393/1080.2.abstract">sixth mass extinction event</a> and amphibians are among the hardest hit. </p>
<p>But in the island of New Guinea, home to 6% of the world’s frog species, there’s a rare opportunity to save them from the potential conservation disaster of a chytrid fungus outbreak.</p>
<p>The amphibian chytrid fungus is a microscopic, aquatic fungus that infects a protein in frog skin. It interferes with the balance of electrolytes and, in turn, effectively gives frogs a heart attack. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tiny-frogs-face-a-troubled-future-in-new-guineas-tropical-mountains-75210">Tiny frogs face a troubled future in New Guinea's tropical mountains</a>
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<p>If the amphibian chytrid fungus invades New Guinea, we estimate 100 species of frogs could decline or become extinct. This disease, which emerged in the 1980s, has already wiped out <a href="https://science.sciencemag.org/content/363/6434/1459.abstract">90 species of frogs</a> around the world.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/277544/original/file-20190603-69079-1gj1ssk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&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 New Guinean horned land frog, <em>Sphenophryne cornuta</em>, with young. These frogs are under threat from a fungus that has wiped out 90 frog species around the world.</span>
<span class="attribution"><span class="source">Stephen Richards</span></span>
</figcaption>
</figure>
<p>Collaborating with 30 international scientists, we <a href="https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/fee.2057">developed a way</a> to save New Guinea’s frog species from a mass extinction, one that’s predictable and preventable. We need urgent, unified, international action to prepare for the arrival of the deadly fungus, to slow its spread after it arrives and to limit its impact on the island. </p>
<p>It’s rare we can identify a conservation disaster before it occurs, but a long history of amphibian declines in Australia and South America has equipped us with the <a href="https://frontiersinzoology.biomedcentral.com/articles/10.1186/1742-9994-8-8">knowledge</a> to protect areas where the amphibian chytrid fungus is yet to reach.</p>
<h2>Why we should care about frogs</h2>
<p>Like Australian frogs, New Guinea frogs may be particularly vulnerable to the chytrid fungus. These frogs share a close genetic relationship suggesting that, if exposed, New Guinea frogs may respond similarly to Australian ones, where around 16% of frog species are affected. </p>
<p>Impacted frogs include <a href="https://theconversation.com/australian-endangered-species-southern-corroboree-frog-16189">corroboree frogs</a>, <a href="https://www.iucnredlist.org/species/14969/4484777">Australian lacelid frogs</a> and <a href="https://www.iucnredlist.org/species/12143/3325402">green and golden bell frogs</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australian-endangered-species-southern-corroboree-frog-16189">Australian endangered species: Southern Corroboree Frog</a>
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<p>Losing so many species can have many terrible impacts. Tadpoles and frogs are important because they help recycle nutrients and break down leaf litter. They are also prey for larger mammals and reptiles, and predators of insects, invertebrates and small vertebrates. They help keep insect plagues, such as those from flies and mosquitoes, in check. </p>
<p>Frogs are also an important source of human medical advancements – they were even used for a <a href="https://www.smithsonianmag.com/smart-news/doctors-used-to-use-live-african-frogs-as-pregnancy-tests-64279275/">human pregnancy test until the 1950s</a>.</p>
<h2>A call to action to protect frogs</h2>
<p>Frogs are one of the most threatened groups of species in the world – <a href="https://www.iucnredlist.org/species/12143/3325402">around 40% are threatened with extinction</a>.</p>
<p>And species conservation is more expensive once the species are threatened. They can be more costly to collect and more precious to maintain, with a greater need for wider input from recovery groups to achieve rapid results.</p>
<p>In our study, we highlight the increased costs and requirements for establishing captive breeding for two species of closely related barred frog, one common and one threatened. We determined that waiting until a species is threatened dramatically increases the costs and effort required to establish a successful breeding program. The risks of it failing also increase. </p>
<p>Our research draws on lessons learned from other emerging diseases and approaches taken in other countries. By addressing the criteria of preparedness, prevention, detection, response and recovery, we detail a call for action to protect the frogs of New Guinea. It will require dedicated funding, a contingency plan for the likely, eventual arrival of the disease and a task force to oversee it. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/frogs-v-fungus-time-is-running-out-to-save-seven-unique-species-from-disease-57432">Frogs v fungus: time is running out to save seven unique species from disease</a>
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<p>This task force would oversee active monitoring for disease and prepare an action plan to implement on the disease’s arrival. We have already begun to establish facilities that can handle captive breeding and gene banking for frogs in collaboration with PNG counterparts.</p>
<p>The need for <a href="https://science.sciencemag.org/content/357/6350/454.summary">amphibian conservation in New Guinea</a> also presents an opportunity for investment and training of local scientists. More species unknown to science will be described and the secret habits of these unique frogs will be discovered before they are potentially lost.</p>
<h2>Conservation in New Guinea is complicated</h2>
<p>The island of New Guinea is governed by Papua New Guinea on the eastern side and Indonesia on the western side. So it will take a coordinated approach to reduce risks in both countries for successful biosecurity.</p>
<p>Historically, New Guinea has had little import or <a href="https://www.ifc.org/wps/wcm/connect/news_ext_content/ifc_external_corporate_site/news+and+events/news/attracting+tourists+to+papua+new+guinea">tourism</a>. But as the <a href="http://www.agriculture.gov.au/about/media-centre/media-releases/working-png-strengthen-aus-biosecurity">country develops</a>, it becomes more at risk of emerging diseases through increased trade and and entry of tourists from chytrid-infected regions, especially with little biosecurity at entry ports. </p>
<p>What’s more, many species there are unknown to science and few ecological studies have documented their habitat requirements. Unlike Australia, many of New Guinea’s frogs have adapted for life in the wet rainforest. </p>
<p>Rather than developing into tadpoles that live in water, more than 200 frog species in New Guinea hatch from their eggs as fully formed baby frogs. It’s difficult for us to predict how the amphibian chytrid fungus will affect these frogs because Australia has only a handful of these types of species. </p>
<p>We don’t know how to remove the amphibian chytrid fungus from large areas once it has invaded, so strict biosecurity and conservation contingency planning is needed to protect New Guinea’s frogs. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/friday-essay-frogwatching-charting-climate-changes-impact-in-the-here-and-now-98161">Friday essay: frogwatching – charting climate change's impact in the here and now</a>
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<p>For example, all incoming goods into New Guinea should be inspected for possible hitchhiker frogs that could carry chytrid. Camping or hiking equipment carried by tourists should also be closely inspected for attached mud, which could harbour the pathogen, as is the case in Australia.</p>
<p>International researchers have experience in emerging amphibian diseases. Papua New Guineans and Indonesians have traditional and ecological expertise. Together we have the opportunity to avert another mass decline of frogs. Without taking action, we could lose a hundred more species from the world and take another step towards mass extinction.</p><img src="https://counter.theconversation.com/content/117842/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Deborah Bower is affiliated with the University of New England.</span></em></p><p class="fine-print"><em><span>Simon Clulow is affiliated with Macquarie University. </span></em></p>The island of New Guinea is home to 6% of the world’s frogs, but if the deadly chytrid fungus invades it could cause a mass extinction.Deborah Bower, Lecturer in Ecosystem Rehabilitation, University of New EnglandSimon Clulow, MQ Research Fellow, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/931202018-04-01T20:29:22Z2018-04-01T20:29:22ZIsland-hopping study shows the most likely route the first people took to Australia<figure><img src="https://images.theconversation.com/files/211422/original/file-20180321-165547-1h6a328.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The view from Indonesia's Rote Island towards Australia.</span> <span class="attribution"><span class="source">Kasih Norman</span>, <span class="license">Author provided</span></span></figcaption></figure><p>The First Australians were among the world’s earliest great ocean explorers, undertaking a remarkable 2,000km maritime migration through Indonesia which led to the discovery of Australia at least <a href="https://www.nature.com/articles/nature22968">65,000 years ago</a>.</p>
<p>But the voyaging routes taken through Indonesia’s islands, and the location of first landfall in Australia, remain a much debated mystery to archaeologists. </p>
<p>Our research, published earlier this year in <a href="https://doi.org/10.1016/j.quascirev.2017.11.023">Quaternary Science Reviews</a>, highlights the most likely route by mapping islands in the region over time through changing sea levels.</p>
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<strong>
Read more:
<a href="https://theconversation.com/cave-dig-shows-the-earliest-australians-enjoyed-a-coastal-lifestyle-77326">Cave dig shows the earliest Australians enjoyed a coastal lifestyle</a>
</strong>
</em>
</p>
<hr>
<h2>A disputed route</h2>
<p>Some archaeologists have argued for an <a href="https://australianmuseum.net.au/the-spread-of-people-to-australia">initial human migration into Australia through New Guinea</a>. This is because islands across northern Indonesia are relatively close together, and people could easily see to the next island they wished to voyage to. </p>
<p>First landfall on Australia has been argued to be both more difficult and <a href="https://doi.org/10.1080/03122417.2012.11681932">less likely</a> than first landfall at New Guinea, as the final crossing distance from Timor to the continental shelf was more than 80km. It was also thought that the Australian landmass was not visible from any Indonesian island. </p>
<p>Despite this, it was proposed that now submerged islands off the Australian continental shelf were visible from Timor. But until recently, computer technology and ocean floor data sets were not developed enough to know for sure.</p>
<h2>A drowned continent</h2>
<p>When people first migrated to Indonesia, reaching Australia by 65,000 years ago, they found a landscape that looked <a href="http://sahultime.monash.edu.au/explore.html">very different</a> from today. During an ice age known as Marine Isotope Stage 4, which stretched from roughly 71,000 to 59,000 years ago, western Indonesia formed part of the Pleistocene continent of Sunda, while Australia and New Guinea were joined to form Sahul. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/211416/original/file-20180321-165568-1bvtx4m.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&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 grey area shows the extent of the ice age continents of Sunda and Sahul, much of which is now under water.</span>
<span class="attribution"><span class="source">Kasih Norman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The rise in global ocean levels at the end of the last ice age at around 18,000 years ago flooded continental shelves across the world, reshaping landmasses. This event drowned the ancient continent of Sunda, creating many of Indonesia’s islands, and split the continent of Sahul into Australia and New Guinea. </p>
<p>This means that what is now under the ocean is very important to understanding where the First Australians might have made landfall.</p>
<h2>On the horizon</h2>
<p>Our <a href="https://www.sciencedirect.com/science/article/pii/S0277379117307333">new research</a> uses computer analyses of visibility between islands and continents. We included landscape surface height data of regions of the ocean floor that were above sea level – and dry land – during the last ice age. </p>
<p>The powerful computer programs we used work out what a person standing at a particular location can see in a 360 degree arc around them, all the way to their horizon. </p>
<p>Running more than 10,000 analyses allowed us to pinpoint where people could see to, from any location on any island or landmass in the whole of Island South East Asia. </p>
<p>But because we knew that so many Indonesian islands, and so much of Sahul, were drowned at the end of the last ice age, we also included ocean floor (bathymetric) data in our analyses. </p>
<h2>Island-hopping</h2>
<p>We discovered that in the deep past (between 70,000 to 60,000 years ago, and potentially for much longer), people could see from the Indonesian islands of Timor and Rote to a now drowned island chain in the Timor Sea. </p>
<p>From this island chain it was possible to sight the Australian continental shelf, which in the last ice age formed a massive fan of islands extending towards Indonesia. Much of this landscape is now more than 100m below the surface of the Timor Sea.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1132&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1132&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210461/original/file-20180315-104639-1d6kpc3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1132&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Regions with visibility between islands and continents during the last ice age are shown by the connective white lines. Dark grey regions represent the now submerged ice age continent of Sahul, light grey shows landmasses above modern sea level.</span>
<span class="attribution"><span class="source">Kasih Norman</span></span>
</figcaption>
</figure>
<p>As the island chain sat at the midpoint between southern Indonesia and Australia, it could have acted as a stepping-stone for Australia’s first maritime explorers. </p>
<h2>To Australia</h2>
<p>Including the areas of the ocean floor that were dry land in the last ice age means we were able to show that people could see from one island to the next, allowing them to island-hop between visually identifiable landmasses all the way to northern Australia.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ice-age-art-and-jewellery-found-in-an-indonesian-cave-reveal-an-ancient-symbolic-culture-75390">Ice age art and 'jewellery' found in an Indonesian cave reveal an ancient symbolic culture</a>
</strong>
</em>
</p>
<hr>
<p>These new findings potentially solve another mystery: all of the oldest archaeological sites for Sahul are found in northwest Australia. If people island-hopped from Timor and Rote they would have arrived on the now submerged coastline close to all of Australia’s most ancient occupation sites, such as <a href="https://www.nature.com/articles/nature22968">Madjedbebe</a>, <a href="https://www.sciencedirect.com/science/article/pii/0277379194900809">Nauwalabila</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0277379117302640">Boodie Cave</a>.</p>
<p>But while we might be closer to understanding where people first reached Australia, signs of the earliest explorers to reach Indonesia have been more elusive.</p>
<p>A team of researchers from the Australian Research Council’s new Centre of Excellence for Australian Biodiversity and Heritage (<a href="https://epicaustralia.org.au/">CABAH</a>) and their partner institution, Indonesia’s National Centre for Archaeology, have now begun the search on Rote and West Timor for the earliest evidence of the region’s first human maritime explorers, the likely ancestors of the First Australians.</p><img src="https://counter.theconversation.com/content/93120/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kasih Norman received funding to undertake this research from the Australian Institute of Nuclear Science and Engineering (AINSE Research Award ALNGRA15001) and from the Australian Archaeological Association Student Research Grant.</span></em></p>There is plenty of debate over what route was taken by the first people to reach Australia. New research reveals a likely route through a now submerged chain of islands.Kasih Norman, PhD Candidate, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/758882017-04-18T14:50:54Z2017-04-18T14:50:54ZNew Guinea’s indigenous tribes are alive and well (just don’t call them ‘ancient’)<figure><img src="https://images.theconversation.com/files/165116/original/image-20170412-25898-l4hkdr.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">Katiekk / shutterstock</span></span></figcaption></figure><p>In <a href="http://www.bbc.co.uk/programmes/b08jns7w">Down the Mighty River with Steve Backshall</a>, the adventurer and naturalist took a journey through New Guinea, the world’s second largest island. As he travelled along the Baliem River, through some of the densest jungle on the planet, Backshall visited the Dani people, which the BBC described as an “ancient tribe”.</p>
<p>I spent two years living with groups not far from the Dani, and was disappointed to hear this sort of language still being used. This distorted perspective perpetuates the myth of the “living fossil” or the “backwards tribe”. </p>
<p>After all, what exactly is an “ancient tribe”? Surely, by definition, an ancient tribe is either really, really old, or really, really dead. The Dani are neither. Nor are they “backward”. The 25,000 or so Dani people scattered across the Baliem Valley are very much alive and well, prospering in a challenging region despite being faced with land dispossession from mining, military control from Indonesia, and the occasional film crew from “the West”. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=302&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=302&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=302&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=380&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=380&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165255/original/image-20170413-25875-18m05jf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=380&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Just north of Australia, New Guinea is divided between Indonesia (west) and Papua New Guinea (east).</span>
<span class="attribution"><span class="source">Rainer Lesniewski / shutterstock</span></span>
</figcaption>
</figure>
<p>Indeed, the Dani have featured in several TV and film documentaries over the years. The first of these, <a href="http://www.der.org/films/dead-birds.html">Dead Birds</a>, made in the early 1960s by anthropologist-filmmaker <a href="http://hcl.harvard.edu/hfa/collections/gardner.html">Robert Gardner</a>, followed two males as they went about their everyday business. Back then, the Dani were a model of “tribal culture” representing what was fast becoming an elusive example of “stone-age man”. They used stone tools, practised gift exchange and fought over territory. </p>
<p>Such practices were typical across the island of New Guinea, particularly in the vast central highlands. Over 50,000 years of habitation, this almost impenetrable rainforest proved the ideal environment for developing permanent agriculture, complete with drainage canals.</p>
<p>The Dani themselves were only first “discovered” in 1938 when, completely by chance, a pilot flying overhead spotted their cultivated fields. But they had long been part of a complex social network of exchange and interaction that reached across the island. Even the government patrols and prospectors that once infested New Guinea were restricted to more accessible coastal regions, so the island’s rural inhabitants continued farming, trading and intermarrying across huge distances. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"841219788550545411"}"></div></p>
<p>By the time of “discovery”, the indigenous population had, politically, already been divided in two. In 1828, European colonisers separated New Guinea in half, right down the 141st meridian. By 1963 the western half was formally annexed to Indonesia, while the east became formally detached from Australia in 1975 to form the independent state of Papua New Guinea. </p>
<p>The Dani people are therefore governed ultimately from the Indonesian capital Jakarta, some 3,500km away, while an international border separates them from their kin in Papua New Guinea. These culturally and historically-linked groups have been fighting ever since to <a href="https://www.theguardian.com/world/2016/may/03/west-papua-un-must-supervise-vote-on-independence-says-coalition">release West Papua from Indonesia</a>.</p>
<h2>Stone axes, grass skirts, missing fingers</h2>
<p>The region’s cultural complexity has made it an ideal location for anthropologists, and my own work has taken me to the Kutubu and Ok Tedi regions in Papua New Guinea. In Ok Tedi, which lies just the other side of the 141st meridian, my friends and hosts were very similar to the Dani people that Backshall met. Like the Dani, they value the <em>sal kambun</em> (penis gourd) and <em>bul bul</em> (grass skirts) as symbols of identity, and they value the stone axe for its practical ability to outlive and outperform the modern alternatives sent to replace it – steel axes and knives. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=263&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=263&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=263&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=330&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=330&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165078/original/image-20170412-25898-1li1cq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=330&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 filming ‘From the Horse’s Mouth: perceptions of development from Papua New Guinea’ in Ok Tedi.</span>
<span class="attribution"><a class="source" href="https://www.youtube.com/watch?v=YINCk0zPkWE&feature=youtu.be">Emma Gilberthorpe</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The ritual amputation of digits is common across the island. As anthropologist Karl Heider recalls in his <a href="https://www.abebooks.co.uk/book-search/title/grand-valley-dani-peaceful-warriors/author/heider-karl/">ethnographic examination of the Dani</a>, close female relatives of males killed in warfare (not those who die from “natural” causes) “have their fingers chopped off”. This is not unique to the Dani; in fact digit/hand amputation was not unusual among men and women across the highland region before missionary intervention. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165216/original/image-20170413-25875-2xaus6.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">A mummified village elder in the Baliem Valley.</span>
<span class="attribution"><span class="source">Katiekk / shutterstock</span></span>
</figcaption>
</figure>
<p>In one of his most memorable scenes, Backshall was invited to sleep alongside the smoke-dried remains of a legendary village elder. Such mummification is actually quite rare across the highlands, even among the Dani, who <a href="https://www.abebooks.co.uk/book-search/title/grand-valley-dani-peaceful-warriors/author/heider-karl/">according to Heider</a> cremate the dead in a detailed and lengthy series of funerary rites. The practice is typically associated with the <a href="http://onlinelibrary.wiley.com/doi/10.1002/ar.23139/full">Anga language group</a> in Papua New Guinea and likely spread eastwards to the Dani.</p>
<p>In recent years, the Dani have been affected by mining, tourism and ongoing attempts to “Indonesianise” their highland culture. But perhaps the biggest threat of all comes from the military presence representing Indonesian interests in a resource-rich land with what they see as a “backwards” culture. Like the colonialists who described the vast area of internal New Guinea as “uninhabited”, government bodies and multinationals still view rural landscapes as <em>Terra nullius</em>, “no-one’s land”.</p>
<p>The illusion of “no-one’s land” and “the ancient tribe” is not helpful to the amazing people who live there. My friends in Ok Tedi and Kutubu are artists, school teachers, academics, gardeners, widows, businessmen and businesswomen. And yet, everything they do remains tightly entwined by a rich, resilient and dynamic culture.</p><img src="https://counter.theconversation.com/content/75888/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Gilberthorpe 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 Dani people were part of a thriving agricultural society long before Westerners ‘discovered’ them in the 1930s.Emma Gilberthorpe, Senior Lecturer in Anthropology, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/752102017-03-30T19:13:33Z2017-03-30T19:13:33ZTiny frogs face a troubled future in New Guinea’s tropical mountains<figure><img src="https://images.theconversation.com/files/162785/original/image-20170327-3263-e2nzs6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A tiny _Choerophryne_ frog from the Foja Mountains in New Guinea. This one is a calling male. </span> <span class="attribution"><span class="source">Tim Laman</span>, <span class="license">Author provided</span></span></figcaption></figure><p>At night, the mountain forests of New Guinea come alive with weird buzzing and beeping calls made by tiny frogs, some no bigger than your little fingernail. </p>
<p>These little amphibians – in the genus <em>Choerophryne</em> – would shrivel and dry up in mere minutes in the hot sun, so they are most common in the rainy, cooler mountains.</p>
<p>Yet many isolated peaks, especially along northern New Guinea, have their own local species of these frogs.</p>
<p>So how did localised and distinctive species of these tiny frogs come to be on these isolated peaks, separated from each other by hotter, drier and rather inhospitable lowlands? </p>
<p>Our new study of their DNA, published this week in the <a href="http://doi.org/10.7717/peerj.3077">open access journal PeerJ</a>, reveals how they achieved this feat. It reveals a dynamic past, and more worryingly it highlights the future vulnerability of tropical mountain forests and their rich biodiversity.</p>
<figure class="align-center zoomable">
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<figcaption>
<span class="caption">A tiny <em>Choerophyrne</em> frog perched on a finger.</span>
<span class="attribution"><span class="source">Tim Laman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>A hotspot of frog diversity</h2>
<p>New Guinea has an astounding diversity of frogs: more than 450 known species and counting. This is nearly double the diversity in Australia, a landmass ten times larger. </p>
<p>Remarkably, a majority of these species are in a single species-rich, ecologically diverse group that have dispensed with the tadpole stage. </p>
<p>Instead they hatch out of their eggs <a href="http://frogsaregreen.org/tag/frog-parental-care/">as tiny little replicas of the adults</a>. Because they do not depend on still pools of water to breed, they do really well in the incredibly wet, but steep mountains of New Guinea.</p>
<p>One of our group (Stephen Richards) has been collecting DNA from frogs across New Guinea for the past 20 years. This work is at times arduous and painful. Having a leech worm its way into the back of one’s eye, and then stay there for more than a week, is not pleasant. </p>
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<a href="https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/162861/original/image-20170328-21243-xwqo85.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">Mud, glorious mud: The wet forests of the New Guinea Mountains are great for frogs, but pose challenges for biologists.</span>
<span class="attribution"><span class="source">Tim Laman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But these trips are also extremely rewarding. So far we have described more than 70 new species, and discovered many more that await description. </p>
<p>They also provide opportunities to explore some of world’s most wild places. Perhaps the best example is the <a href="http://news.nationalgeographic.com/news/2010/05/photogalleries/100517-new-species-lost-world-foja-science-pictures/">first scientific expedition</a> to the remote Foja Mountains. </p>
<iframe src="https://www.google.com/maps/embed?pb=!1m18!1m12!1m3!1d7270965.6870389925!2d137.15092980357264!3d-2.80156269666386!2m3!1f0!2f0!3f0!3m2!1i1024!2i768!4f13.1!3m3!1m2!1s0x6813959f91706d4b%3A0x4ad2a1c2af71f248!2sFoja+Mountains!5e0!3m2!1sen!2sau!4v1490841522653" width="100%" height="450" frameborder="0" style="border:0" allowfullscreen=""></iframe>
<p>This isolated mountain range in northern New Guinea was previously almost unexplored, but revealed a treasure trove of diversity, including a <a href="http://news.bbc.co.uk/2/hi/science/nature/4688000.stm">“lost” bird of paradise</a>, a completely new species of another bird, and a <a href="https://www.newscientist.com/gallery/dn18919-pinocchio-frog-and-dwarf-wallaby-new-species-found/">bizarre treefrog with an erectile nose</a>. </p>
<p>We also found several species of <em>Choerophryne</em> frog. DNA from these allowed our team to test two potential ways that miniature frogs could have come to occupy distant mountain peaks that are separated by inhospitable lowlands.</p>
<h2>Across the Fojas by frog</h2>
<p>The first way involves mountain-top frogs evolving separately on each isolated peak, potentially from larger frogs capable of surviving in the hotter and drier, nearby lowlands.</p>
<p>If this were the case, the frog on any given mountaintop would be most genetically similar to frogs from adjoining lowlands.</p>
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<a href="https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/162860/original/image-20170328-21261-1cyv0ay.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">The cloud-shrouded summits of the Foja mountaintops were first reached by scientists in 2008.</span>
<span class="attribution"><span class="source">Tim Laman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The other way involves exploiting climate change. During past phases of global cooling (glacial periods), the colder, wetter, mountainous habitats of New Guinea expanded downhill, a process termed elevational depression.</p>
<p>If depression was extensive enough, the frogs on one mountain might have been able to travel across tracts of cool, wet lowlands to colonise other mountains. </p>
<p>Later, a warming climate would wipe out the lowland populations, leaving two isolated mountain populations, which might eventually become new species.</p>
<p>If this were the case, we would expect the frogs in different mountains to be genetically related, since they almost literally hopped from one peak to the other.</p>
<p>Our new study of the DNA of the little <em>Choerophryne</em> frogs indicates they used both routes to conquer the peaks of New Guinea.</p>
<p>In the remote Foja mountains, for example, there are three species of <em>Choerophryne</em>. One species has evolved <em>in situ</em> in northern New Guinea from nearby lowland frogs. </p>
<p>The other two are related to frogs from distant mountains of central New Guinea, and presumably moved across the intervening lowlands during cooler glacial periods.</p>
<h2>The little frogs and the future</h2>
<p>Why does it matter how the tiny frogs moved to their mountain habitats? Because it could be a warning to their future survival.</p>
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<a href="https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/162862/original/image-20170328-21225-1vaf7k1.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">The range of wet, mossy forest found at the Foja mountain tops and its rich biodiversity is likely to shrink as global temperatures soar.</span>
<span class="attribution"><span class="source">Tim Laman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Tropical mountains have some of the most biodiverse assemblages of plants and animals in the world. Their ecosystems are also far more dynamic than is popularly recognised. </p>
<p>Just like glaciers, the movements of frogs (and other organisms) up and down mountains has tracked global temperatures. As we’ve shown, the global cooling in past glacial periods allowed the mountain-dwelling frogs to move down across the lowlands to find new mountain peaks.</p>
<p>But today, as global temperatures soar to levels not seen for millions of years, their habitable cool zones are heading in the other direction: shrinking uphill. </p>
<p>We have no idea how quickly these frogs will respond to these changes, but recent research elsewhere in New Guinea has found <a href="https://phys.org/news/2014-02-warmer-temps-tropical-birds-mountains.html">birds are already shifting upslope rapidly</a>.</p>
<p>We don’t yet know what could happen to these cute little amphibians should temperatures continue to climb, and they in turn run out of mountainside to climb.</p>
<p>It’s more than ten years since the first expeditions to the Foja Mountains, and this study provides a great demonstration of the ongoing value of the scientific data collected on these trips. </p>
<p>We now have a snapshot of the distinctive frogs (and many other animals) that live at the tops of these remote mountains, and a window into their past.</p>
<p>This provides an incredibly important resource to help us understand the dynamic history of these mountain forests, and reminds us that despite their inaccessibility, they face an uncertain future.</p>
<hr>
<p><em>Stephen John Richards, a research associate in systematics, biogeography and conservation of amphibians, at The South Australian Museum, was a co-author on this article.</em></p><img src="https://counter.theconversation.com/content/75210/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Oliver is currently funded by a grant from the Australian Research Council and Australian National University. His work in New Guinea has been supported by Conservation International, National Geographic and the Australia & Pacific Science Foundation. </span></em></p><p class="fine-print"><em><span>Mike Lee has received funding for New Guinea frog research from the Australia & Pacific Science Foundation.</span></em></p>Tiny frogs that have spread across New Guinea’s isolated mountains could face an uncertain future if a warming climate pushes them higher up the peaks.Paul Oliver, Postdoctoral Researcher in Biodiversity and Evolution, Australian National UniversityMike Lee, Professor in Evolutionary Biology (jointly appointed with South Australian Museum), Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.