ֱ̽ of Cambridge - evolution /taxonomy/subjects/evolution en Genetic study reveals hidden chapter in human evolution /research/news/genetic-study-reveals-hidden-chapter-in-human-evolution <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/gettyimages-506356472-dp.jpg?itok=oPsh3EiG" alt="Plaster reconstructions of the skulls of human ancestors" title="Plaster reconstructions of the skulls of human ancestors, Credit: Jose A Bernat Bacete via Getty Images" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Using advanced analysis based on full genome sequences, researchers from the ֱ̽ of Cambridge have found evidence that modern humans are the result of a genetic mixing event between two ancient populations that diverged around 1.5 million years ago. About 300,000 years ago, these groups came back together, with one group contributing 80% of the genetic makeup of modern humans and the other contributing 20%.</p> <p>For the last two decades, the prevailing view in human evolutionary genetics has been that Homo sapiens first appeared in Africa around 200,000 to 300,000 years ago, and descended from a single lineage. However, these latest <a href="https://www.nature.com/articles/s41588-025-02117-1">results</a>, reported in the journal <em>Nature Genetics</em>, suggest a more complex story.</p> <p>“ ֱ̽question of where we come from is one that has fascinated humans for centuries,” said first author Dr Trevor Cousins from Cambridge’s Department of Genetics. “For a long time, it’s been assumed that we evolved from a single continuous ancestral lineage, but the exact details of our origins are uncertain.”</p> <p>“Our research shows clear signs that our evolutionary origins are more complex, involving different groups that developed separately for more than a million years, then came back to form the modern human species,” said co-author Professor Richard Durbin, also from the Department of Genetics.</p> <p>While earlier research has already shown that Neanderthals and Denisovans – two now-extinct human relatives – interbred with Homo sapiens around 50,000 years ago, this new research suggests that long before those interactions – around 300,000 years ago – a much more substantial genetic mixing took place. Unlike Neanderthal DNA, which makes up roughly 2% of the genome of non-African modern humans, this ancient mixing event contributed as much as 10 times that amount and is found in all modern humans.</p> <p> ֱ̽team’s method relied on analysing modern human DNA, rather than extracting genetic material from ancient bones, and enabled them to infer the presence of ancestral populations that may have otherwise left no physical trace. ֱ̽data used in the study is from the 1000 Genomes Project, a global initiative that sequenced DNA from populations across Africa, Asia, Europe, and the Americas.</p> <p> ֱ̽team developed a computational algorithm called cobraa that models how ancient human populations split apart and later merged back together. They tested the algorithm using simulated data and applied it to real human genetic data from the 1000 Genomes Project.</p> <p>While the researchers were able to identify these two ancestral populations, they also identified some striking changes that happened after the two populations initially broke apart.</p> <p>“Immediately after the two ancestral populations split, we see a severe bottleneck in one of them—suggesting it shrank to a very small size before slowly growing over a period of one million years,” said co-author Professor Aylwyn Scally, also from the Department of Genetics. “This population would later contribute about 80% of the genetic material of modern humans, and also seems to have been the ancestral population from which Neanderthals and Denisovans diverged.”</p> <p> ֱ̽study also found that genes inherited from the second population were often located away from regions of the genome linked to gene functions, suggesting that they may have been less compatible with the majority genetic background. This hints at a process known as purifying selection, where natural selection removes harmful mutations over time.</p> <p>“However, some of the genes from the population which contributed a minority of our genetic material, particularly those related to brain function and neural processing, may have played a crucial role in human evolution,” said Cousins.</p> <p>Beyond human ancestry, the researchers say their method could help to transform how scientists study the evolution of other species. In addition to their analysis of human evolutionary history, they applied the cobraa model to genetic data from bats, dolphins, chimpanzees, and gorillas, finding evidence of ancestral population structure in some but not all of these.</p> <p>“What’s becoming clear is that the idea of species evolving in clean, distinct lineages is too simplistic,” said Cousins. “Interbreeding and genetic exchange have likely played a major role in the emergence of new species repeatedly across the animal kingdom.”</p> <p>So who were our mysterious human ancestors? Fossil evidence suggests that species such as Homo erectus and Homo heidelbergensis lived both in Africa and other regions during this period, making them potential candidates for these ancestral populations, although more research (and perhaps more evidence) will be needed to identify which genetic ancestors corresponded to which fossil group.</p> <p>Looking ahead, the team hopes to refine their model to account for more gradual genetic exchanges between populations, rather than sharp splits and reunions. They also plan to explore how their findings relate to other discoveries in anthropology, such as fossil evidence from Africa that suggests early humans may have been far more diverse than previously thought.</p> <p>“ ֱ̽fact that we can reconstruct events from hundreds of thousands or millions of years ago just by looking at DNA today is astonishing,” said Scally. “And it tells us that our history is far richer and more complex than we imagined.”</p> <p> ֱ̽research was supported by Wellcome. Aylwyn Scally is a Fellow of Darwin College, Cambridge. Trevor Cousins is a member of Darwin College, Cambridge.</p> <p> </p> <p><em><strong>Reference:</strong><br /> Trevor Cousins, Aylwyn Scally &amp; Richard Durbin. ‘<a href="https://www.nature.com/articles/s41588-025-02117-1">A structured coalescent model reveals deep ancestral structure shared by all modern humans</a>.’ Nature Genetics (2025). DOI: 10.1038/s41588-025-02117-1</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Modern humans descended from not one, but at least 2 ancestral populations that drifted apart and later reconnected, long before modern humans spread across the globe.</p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Our history is far richer and more complex than we imagined</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Aylwyn Scally</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="https://www.gettyimages.co.uk/detail/photo/reconstruction-with-plasters-to-royal-scale-of-royalty-free-image/506356472" target="_blank">Jose A Bernat Bacete via Getty Images</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Plaster reconstructions of the skulls of human ancestors</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Tue, 18 Mar 2025 10:00:00 +0000 sc604 248776 at Bird brain from the age of dinosaurs reveals roots of avian intelligence /stories/roots-of-bird-intelligence <div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>A ‘one of a kind’ fossil discovery could transform our understanding of how the unique brains and intelligence of modern birds evolved, one of the most enduring mysteries of vertebrate evolution.</p> </p></div></div></div> Wed, 13 Nov 2024 14:20:58 +0000 sc604 248548 at ‘Palaeo-robots’ to help scientists understand how fish started to walk on land /research/news/palaeo-robots-to-help-scientists-understand-how-fish-started-to-walk-on-land <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/paleo-robots-883x432.jpg?itok=rSGMB0cY" alt="Illustration of palaeo-robots." title="Credit: None" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://doi.org/10.1126/scirobotics.adn1125">Writing</a> in the journal <em>Science Robotics</em>, the research team, led by the ֱ̽ of Cambridge, outline how ‘palaeo-inspired robotics’ could provide a valuable experimental approach to studying how the pectoral and pelvic fins of ancient fish evolved to support weight on land.</p> <p>“Since fossil evidence is limited, we have an incomplete picture of how ancient life made the transition to land,” said lead author <a href="https://www.michaelishida.com/">Dr Michael Ishida</a> from Cambridge’s Department of Engineering. “Palaeontologists examine ancient fossils for clues about the structure of hip and pelvic joints, but there are limits to what we can learn from fossils alone. That’s where robots can come in, helping us fill gaps in the research, particularly when studying major shifts in how vertebrates moved.”</p> <p>Ishida is a member of Cambridge’s <a href="https://birlab.org/">Bio-Inspired Robotics Laboratory</a>, led by Professor Fumiya Iida. ֱ̽team is developing energy-efficient robots for a variety of applications, which take their inspiration from the efficient ways that animals and humans move.</p> <p>With funding from the Human Frontier Science Program, the team is developing palaeo-inspired robots, in part by taking their inspiration from modern-day ‘walking fish’ such as mudskippers, and from fossils of extinct fish. “In the lab, we can’t make a living fish walk differently, and we certainly can’t get a fossil to move, so we’re using robots to simulate their anatomy and behaviour,” said Ishida.</p> <p> ֱ̽team is creating robotic analogues of ancient fish skeletons, complete with mechanical joints that mimic muscles and ligaments. Once complete, the team will perform experiments on these robots to determine how these ancient creatures might have moved.</p> <p>“We want to know things like how much energy different walking patterns would have required, or which movements were most efficient,” said Ishida. “This data can help confirm or challenge existing theories about how these early animals evolved.”</p> <p>One of the biggest challenges in this field is the lack of comprehensive fossil records. Many of the ancient species from this period in Earth’s history are known only from partial skeletons, making it difficult to reconstruct their full range of movement.</p> <p>“In some cases, we’re just guessing how certain bones connected or functioned,” said Ishida. “That’s why robots are so useful—they help us confirm these guesses and provide new evidence to support or rebut them.”</p> <p>While robots are commonly used to study movement in living animals, very few research groups are using them to study extinct species. “There are only a few groups doing this kind of work,” said Ishida. “But we think it’s a natural fit – robots can provide insights into ancient animals that we simply can’t get from fossils or modern species alone.”</p> <p> ֱ̽team hopes that their work will encourage other researchers to explore the potential of robotics to study the biomechanics of long-extinct animals. “We’re trying to close the loop between fossil evidence and real-world mechanics,” said Ishida. “Computer models are obviously incredibly important in this area of research, but since robots are interacting with the real world, they can help us test theories about how these creatures moved, and maybe even why they moved the way they did.”</p> <p> ֱ̽team is currently in the early stages of building their palaeo-robots, but they hope to have some results within the next year. ֱ̽researchers say they hope their robot models will not only deepen understanding of evolutionary biology, but could also open up new avenues of collaboration between engineers and researchers in other fields.</p> <p> ֱ̽research was supported by the Human Frontier Science Program. Fumiya Iida is a Fellow of Corpus Christi College, Cambridge. Michael Ishida a Postdoctoral Research Associate at Gonville and Caius College, Cambridge.</p> <p><em><strong>Reference:</strong><br /> Michael Ishida et al. ‘<a href="https://doi.org/10.1126/scirobotics.adn1125">Paleo-inspired robotics as an experimental approach to the history of life</a>.’ Science Robotics (2024). DOI: 10.1126/scirobotics.adn1125</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p> ֱ̽transition from water to land is one of the most significant events in the history of life on Earth. Now, a team of roboticists, palaeontologists and biologists is using robots to study how the ancestors of modern land animals transitioned from swimming to walking, about 390 million years ago.</p> </p></div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 23 Oct 2024 18:00:00 +0000 sc604 248514 at ‘Missing’ sea sponges discovered /research/news/missing-sea-sponges-discovered <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/black-fossil-crop.jpg?itok=Q9Pu6_XU" alt="Heliocolocellus fossil" title="Heliocolocellus fossil, Credit: Xiaopeng Wang" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>At first glance, the simple, spikey sea sponge is no creature of mystery.</p> <p>No brain. No gut. No problem dating them back 700 million years. Yet convincing sponge fossils only go back about 540 million years, leaving a 160-million-year gap in the fossil record.</p> <p>In a <a href="https://www.nature.com/articles/s41586-024-07520-y">paper</a> released in the journal <em>Nature</em>, an international team including researchers from the ֱ̽ of Cambridge, have reported a 550-million-year-old sea sponge from the “lost years” and proposed that the earliest sea sponges had not yet developed mineral skeletons, offering new parameters to the search for the missing fossils.</p> <p> ֱ̽mystery of the missing sea sponges centred on a paradox.</p> <p>Molecular clock estimates, which involve measuring the number of genetic mutations that accumulate within the Tree of Life over time, indicate that sponges must have evolved about 700 million years ago. And yet, there had been no convincing sponge fossils found in rocks that old.</p> <p>For years, this conundrum was the subject of debate among zoologists and palaeontologists.</p> <p>This latest discovery fills in the evolutionary family tree of one of the earliest animals, connecting the dots all the way back to Darwin’s questions about when the first animals evolved and explaining their apparent absence in older rocks.</p> <p>Shuhai Xiao from Virginia Tech, who led the research, first laid eyes on the fossil five years ago when a collaborator texted him a picture of a specimen excavated along the Yangtze River in China. “I had never seen anything like it before,” he said. “Almost immediately, I realised that it was something new.”</p> <p> ֱ̽researchers began ruling out possibilities one by one: not a sea squirt, not a sea anemone, not a coral. They wondered, could it be an elusive ancient sea sponge?</p> <p>In an earlier study published in 2019, Xiao and his team suggested that early sponges left no fossils because they had not evolved the ability to generate the hard needle-like structures, known as spicules, that characterise sea sponges today.</p> <p> ֱ̽team traced sponge evolution through the fossil record. As they went further back in time, sponge spicules were increasingly more organic in composition, and less mineralised.</p> <p>“If you extrapolate back, then perhaps the first ones were soft-bodied creatures with entirely organic skeletons and no minerals at all,” said Xiao. “If this was true, they wouldn’t survive fossilisation except under very special circumstances where rapid fossilisation outcompeted degradation.”</p> <p>Later in 2019, Xiao’s group found a sponge fossil preserved in just such a circumstance: a thin bed of marine carbonate rocks known to preserve abundant soft-bodied animals, including some of the earliest mobile animals. Most often this type of fossil would be lost to the fossil record. ֱ̽new finding offers a window into early animals before they developed hard parts.</p> <p> ֱ̽surface of the new sponge fossil is studded with an intricate array of regular boxes, each divided into smaller, identical boxes.</p> <p>“This specific pattern suggests our fossilised sea sponge is most closely related to a certain species of glass sponges,” said first author Dr Xiaopeng Wang, from Cambridge’s Department of Earth Sciences and the Nanjing Institute of Geology and Palaeontology.</p> <p>Another unexpected aspect of the new sponge fossil is its size.</p> <p>“When searching for fossils of early sponges I had expected them to be very small,” said co-author Alex Liu from Cambridge’s Department of Earth Sciences. “ ֱ̽new fossil can reach over 40 centimetres long, and has a relatively complex conical body plan, challenging many of our expectations for the appearance of early sponges”.</p> <p>While the fossil fills in some of the missing years, it also provides researchers with important guidance about what they should look for, which will hopefully extend understanding of early animal evolution further back in time.</p> <p>“ ֱ̽discovery indicates that perhaps the first sponges were spongey but not glassy,” said Xiao. “We now know that we need to broaden our view when looking for early sponges.”</p> <p><em><strong>Reference:</strong></em><br /> <em>Xiaopeng Wang et al. ‘<a href="https://www.nature.com/articles/s41586-024-07520-y">A late-Ediacaran crown-group sponge animal</a>.’ Nature (2024). DOI: 10.1038/s41586-024-07520-y</em></p> <p><em>Adapted from a Virginia Tech press release.</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p> ֱ̽discovery, published in Nature, opens a new window on early animal evolution.</p> </p></div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Xiaopeng Wang</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Heliocolocellus fossil</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 05 Jun 2024 12:56:30 +0000 sc604 246361 at Cuckoos evolve to look like their hosts - and form new species in the process /research/news/cuckoos-evolve-to-look-like-their-hosts-and-form-new-species-in-the-process <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/1-horsfields-bronze-cuckoodevils-bend-825x428px.jpg?itok=ojrOeWX6" alt="Male wren with bright blue plumage brings food to a cuckoo fledgling ." title="Male wren (left) brings food to a cuckoo fledgling (right), Credit: Mark Lethlean" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> ֱ̽theory of coevolution says that when closely interacting species drive evolutionary changes in each other this can lead to speciation - the evolution of new species. But until now, real-world evidence for this has been scarce.</p>&#13; &#13; <p>Now a team of researchers has found evidence that coevolution is linked to speciation by studying the evolutionary arms race between cuckoos and the host birds they exploit.</p>&#13; &#13; <p>Bronze-cuckoos lay their eggs in the nests of small songbirds. Soon after the cuckoo chick hatches, it pushes the host’s eggs out of the nest. ֱ̽host not only loses all its own eggs, but spends several weeks rearing the cuckoo, which takes up valuable time when it could be breeding itself.</p>&#13; &#13; <p>Each species of bronze-cuckoo closely matches the appearance of their host’s chicks, fooling the host parents into accepting the cuckoo.</p>&#13; &#13; <p> ֱ̽study shows how these interactions can cause new species to arise when a cuckoo species exploits several different hosts. If chicks of each host species have a distinct appearance, and hosts reject odd-looking nestlings, then the cuckoo species diverges into separate genetic lineages, each mimicking the chicks of its favoured host. These new lineages are the first sign of new species emerging.</p>&#13; &#13; <p> ֱ̽study is <a href="https://doi.org/10.1126/science.adj3210">published today in the journal <em>Science</em></a>.</p>&#13; &#13; <p>“This exciting new finding could potentially apply to any pairs of species that are in battle with each other. Just as we’ve seen with the cuckoo, the coevolutionary arms race could cause new species to emerge - and increase biodiversity on our planet,” said Professor Kilner in the ֱ̽ of Cambridge’s Department of Zoology, a co-author of the report.</p>&#13; &#13; <p> ֱ̽striking differences between the chicks of different bronze-cuckoo lineages correspond to subtle differences in the plumage and calls of the adults, which help males and females that specialise on the same host to recognise and pair with each other.</p>&#13; &#13; <p>“Cuckoos are very costly to their hosts, so hosts have evolved the ability to recognise and eject cuckoo chicks from their nests,’’ said Professor Naomi Langmore at the Australian National ֱ̽, Canberra, lead author of the study. </p>&#13; &#13; <p>She added: “Only the cuckoos that most resemble the host’s own chicks have any chance of escaping detection, so over many generations the cuckoo chicks have evolved to mimic the host chicks.”</p>&#13; &#13; <p> ֱ̽study revealed that coevolution is most likely to drive speciation when the cuckoos are very costly to their hosts, leading to a ‘coevolutionary arms race’ between host defences and cuckoo counter-adaptations.</p>&#13; &#13; <p>A broad scale analysis across all cuckoo species found that those lineages that are most costly to their hosts have higher speciation rates than less costly cuckoo species and their non-parasitic relatives.</p>&#13; &#13; <p>“This finding is significant in evolutionary biology, showing that coevolution between interacting species increases biodiversity by driving speciation,” said Dr Clare Holleley at the Australian National Wildlife Collection within CSIRO, Canberra, senior author of the report.</p>&#13; &#13; <p> ֱ̽study was made possible by the team’s breakthrough in extracting DNA from eggshells in historical collections, and sequencing it for genetic studies.</p>&#13; &#13; <p> ֱ̽researchers were then able to combine two decades of behavioural fieldwork with DNA analysis of specimens of eggs and birds held in museums and collections.</p>&#13; &#13; <p> ֱ̽study involved an international team of researchers at the ֱ̽ of Cambridge, Australian National ֱ̽, CSIRO (Australia’s national science agency), and the ֱ̽ of Melbourne. It was funded by the Australian Research Council.</p>&#13; &#13; <p><strong><em>Reference: Langmore, N E et al: ‘<a href="https://doi.org/10.1126/science.adj3210">Coevolution with hosts underpins speciation in brood-parasitic cuckoos</a>.’ Science, May 2024. DOI: 10.1126/science.adj3210</em></strong></p>&#13; &#13; <p><em>Adapted from a press release by the Australian National ֱ̽.</em></p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Two decades of cuckoo research have helped scientists to explain how battles between species can cause new species to arise</p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">This exciting new finding could potentially apply to any pairs of species that are in battle with each other...the coevolutionary arms race could cause new species to emerge - and increase biodiversity on our planet</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Rebecca Kilner</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Mark Lethlean</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Male wren (left) brings food to a cuckoo fledgling (right)</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br />&#13; ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div><div class="field field-name-field-license-type field-type-taxonomy-term-reference field-label-above"><div class="field-label">Licence type:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/taxonomy/imagecredit/attribution-noncommerical">Attribution-Noncommerical</a></div></div></div> Thu, 30 May 2024 18:05:07 +0000 jg533 246221 at Earth’s earliest sea creatures drove evolution by stirring the water /research/news/earths-earliest-sea-creatures-drove-evolution-by-stirring-the-water <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/artistic-recreation-of-the-marine-animal-forest-c-hugo-salais-metazoa-studio-crop.jpg?itok=goM-AHMA" alt="Artistic recreation of the marine animal forest" title="Artistic recreation of the marine animal forest, Credit: Hugo Salais, Metazoa Studio" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>A study involving the ֱ̽ of Cambridge has used virtual recreations of the earliest animal ecosystems, known as marine animal forests, to demonstrate the part they played in the evolution of our planet.</p> <p>Using state-of-the-art computer simulations of fossils from the Ediacaran time period - approximately 565 million years ago - scientists discovered how these animals mixed the surrounding seawater. This may have affected the distribution of important resources such as food particles and could have increased local oxygen levels.</p> <p>Through this process, the scientists think these early communities could have played a crucial role in shaping the initial emergence of large and complex organisms prior to a major evolutionary radiation of different forms of animal life, the so-called Cambrian ‘explosion’.</p> <p>Over long periods of time, these changes might have allowed life forms to perform more complicated functions, like those associated with the evolution of new feeding and movement styles.</p> <p> ֱ̽study was led by the Natural History Museum and is published today in the journal <a href="https://doi.org/10.1016/j.cub.2024.04.059"><em>Current Biology</em></a>.</p> <p>Dr Emily Mitchell at the ֱ̽ of Cambridge’s Department of Zoology, a co-author of the report, said: “It’s exciting to learn that the very first animals from 580 million years ago had a significant impact on their environment, despite not being able to move or swim. We’ve found they mixed up the water and enabled resources to spread more widely - potentially encouraging more evolution.”</p> <p>Scientists know from modern marine environments that nutrients like food and oxygen are carried in seawater, and that animals can affect water flow in ways that influence the distribution of these resources.</p> <p>To test how far back this process goes in Earth’s history, the team looked at some of the earliest examples of marine animal communities, known from rocks at Mistaken Point, Newfoundland, Canada. This world-famous fossil site perfectly preserves early life forms thanks to a cover of volcanic ash (sometimes referred to as an ‘Ediacaran Pompeii’).</p> <p>Although some of these life forms look like plants, analysis of their anatomy and growth strongly suggests they are animals. Owing to the exceptional preservation of the fossils, the scientists could recreate digital models of key species, which were used as a basis for further computational analyses.</p> <p>First author Dr Susana Gutarra, a Scientific Associate at the Natural History Museum, said: “We used ecological modelling and computer simulations to investigate how 3D virtual assemblages of Ediacaran life forms affected water flow. Our results showed that these communities were capable of ecological functions similar to those seen in present-day marine ecosystems.”</p> <p> ֱ̽study showed that one of the most important Ediacaran organisms for disrupting the flow of water was the cabbage-shaped animal Bradgatia, named after Bradgate Park in England. ֱ̽Bradgatia from Mistaken Point are among some of the largest fossils known from this site, reaching diameters of over 50 centimetres.</p> <p>Through their influence on the water around them, the scientists believe these Ediacaran organisms might have been capable of enhancing local oxygen concentrations. This biological mixing might also have had repercussions for the wider environment, possibly making other areas of the sea floor more habitable and perhaps even driving evolutionary innovation.</p> <p>Dr Imran Rahman, lead author and Principal Researcher at the Natural History Museum, said: “ ֱ̽approach we’ve developed to study Ediacaran fossil communities is entirely new in palaeontology, providing us with a powerful tool for studying how past and present marine ecosystems might shape and influence their environment.”</p> <p> ֱ̽research was funded by the UK Natural Environment Research Council and the US National Science Foundation.</p> <p><em><strong>Reference: </strong>Gutarra-Diaz, S. “<a href="https://doi.org/10.1016/j.cub.2024.04.059">Ediacaran marine animal forests and the ventilation of the oceans</a>.” May 2024, Current Biology. DOI: 10.1016/j.cub.2024.04.059</em></p> <p><em>Adapted from a press release by the Natural History Museum</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>3D reconstructions suggest that simple marine animals living over 560 million years ago drove the emergence of more complex life by mixing the seawater around them</p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">It’s exciting to learn that the very first animals from 580 million years ago had a significant impact on their environment, despite not being able to move or swim.</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Emily Mitchell</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Hugo Salais, Metazoa Studio</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Artistic recreation of the marine animal forest</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div><div class="field field-name-field-license-type field-type-taxonomy-term-reference field-label-above"><div class="field-label">Licence type:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="/taxonomy/imagecredit/attribution-noncommerical">Attribution-Noncommerical</a></div></div></div> Fri, 17 May 2024 15:01:02 +0000 jg533 246061 at Revealed: face of 75,000-year-old female Neanderthal from cave where species buried their dead /stories/shanidar-z-face-revealed <div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>A new documentary has recreated the face of a 75,000-year-old female Neanderthal whose flattened skull was discovered and rebuilt from hundreds of bone fragments by a team of archaeologists and conservators led by the ֱ̽ of Cambridge.</p> </p></div></div></div> Thu, 02 May 2024 06:46:45 +0000 fpjl2 245821 at Interspecies competition led to even more forms of ancient human – defying evolutionary trends in vertebrates /research/news/interspecies-competition-led-to-even-more-forms-of-ancient-human-defying-evolutionary-trends-in <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/homopicweb.jpg?itok=efUnlDNU" alt="A cast of the skull of Homo Heidelbergensis, one of the hominin species analysed in the latest study." title="A cast of the skull of Homo Heidelbergensis, one of the hominin species analysed in the latest study., Credit: ֱ̽Duckworth Laboratory" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Climate has long been held responsible for the emergence and extinction of hominin species. In most vertebrates, however, interspecies competition is known to play an important role.</p> <p>Now, research shows for the first time that competition was fundamental to 'speciation' – the rate at which new species emerge – across five million years of hominin evolution.</p> <p> ֱ̽study, published today in <em><a href="https://www.nature.com/articles/s41559-024-02390-z">Nature Ecology &amp; Evolution</a></em>, also suggests that the species formation pattern of our own lineage was closer to island-dwelling beetles than other mammals.  </p> <p>“We have been ignoring the way competition between species has shaped our own evolutionary tree,” said lead author Dr Laura van Holstein, a ֱ̽ of Cambridge biological anthropologist at Clare College. “ ֱ̽effect of climate on hominin species is only part of the story.” </p> <p>In other vertebrates, species form to fill ecological “niches” says van Holstein. Take Darwin’s finches: some evolved large beaks for nut-cracking, while others evolved small beaks for feeding on certain insects. When each resource niche gets filled, competition kicks in, so no new finches emerge and extinctions take over.</p> <p>Van Holstein used Bayesian modelling and phylogenetic analyses to show that, like other vertebrates, most hominin species formed when competition for resources or space were low.</p> <p>“ ֱ̽pattern we see across many early hominins is similar to all other mammals. Speciation rates increase and then flatline, at which point extinction rates start to increase. This suggests that interspecies competition was a major evolutionary factor.”</p> <p>However, when van Holstein analysed our own group, Homo, the findings were 'bizarre'.</p> <p>For the Homo lineage that led to modern humans, evolutionary patterns suggest that competition between species actually resulted in the appearance of even more new species – a complete reversal of the trend seen in almost all other vertebrates.</p> <p>“ ֱ̽more species of Homo there were, the higher the rate of speciation. So when those niches got filled, something drove even more species to emerge. This is almost unparalleled in evolutionary science.”</p> <p> ֱ̽closest comparison she could find was in beetle species that live on islands, where contained ecosystems can produce unusual evolutionary trends.</p> <p>“ ֱ̽patterns of evolution we see across species of Homo that led directly to modern humans is closer to those of island-dwelling beetles than other primates, or even any other mammal.”</p> <p>Recent decades have seen the discovery of several new hominin species, from Australopithecus sediba to Homo floresiensis. Van Holstein created a new database of 'occurrences' in the hominin fossil record: each time an example of a species was found and dated, around 385 in total.</p> <p>Fossils can be an unreliable measure of species’ lifetimes. “ ֱ̽earliest fossil we find will not be the earliest members of a species,” said van Holstein.</p> <p>“How well an organism fossilises depends on geology, and on climatic conditions: whether it is hot or dry or damp. With research efforts concentrated in certain parts of the world, and we might well have missed younger or older fossils of a species as a result.”</p> <p>Van Holstein used data modelling to address this problem, and factor in likely numbers of each species at the beginning and end of their existence, as well as environmental factors on fossilisation, to generate new start and end dates for most known hominin species (17 in total).</p> <p>She found that some species thought to have evolved through 'anagenesis' – when one slowly turns into another, but lineage doesn’t split – may have actually 'budded': when a new species branches off from an existing one.</p> <p>For example, the hominin species <em>Australopithecus afarensis</em> was believed to have speciated via anagenesis from <em>Australopithecus anamensis</em>. However, the new data modelling suggests they overlapped by around half a million years.  </p> <p>This meant that several more hominin species than previously assumed were co-existing, and so possibly competing.</p> <p>While early species of hominins, such as Paranthropus, probably evolved physiologically to expand their niche – adapting teeth to exploit new types of food, for example – the driver of the very different pattern in our own genus Homo may well have been technology.</p> <p>“Adoption of stone tools or fire, or intensive hunting techniques, are extremely flexible behaviours. A species that can harness them can quickly carve out new niches, and doesn’t have to survive vast tracts of time while evolving new body plans,” said van Holstein</p> <p>She argues that an ability to use technology to generalise, and rapidly go beyond ecological niches that force other species to compete for habitat and resources, may be behind the exponential increase in the number of Homo species detected by the latest study.</p> <p>But it also led to Homo sapiens – the ultimate generalisers. And competition with an extremely flexible generalist in almost every ecological niche may be what contributed to the extinction of all other Homo species.</p> <p>Added van Holstein: “These results show that, although it has been conventionally ignored, competition played an important role in human evolution overall. Perhaps most interestingly, in our own genus it played a role unlike that across any other vertebrate lineage known so far.”</p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Competition between species played a major role in the rise and fall of hominins, and produced a “bizarre” evolutionary pattern for the Homo lineage.</p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">This is almost unparalleled in evolutionary science</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Laura van Holstein</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank"> ֱ̽Duckworth Laboratory</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">A cast of the skull of Homo Heidelbergensis, one of the hominin species analysed in the latest study.</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 17 Apr 2024 08:06:16 +0000 fpjl2 245721 at