tag:theconversation.com,2011:/us/topics/ancient-humans-52145/articlesAncient humans – The Conversation2023-10-04T19:05:09Ztag:theconversation.com,2011:article/2147192023-10-04T19:05:09Z2023-10-04T19:05:09ZNew path for early human migrations through a once-lush Arabia contradicts a single ‘out of Africa’ origin<figure><img src="https://images.theconversation.com/files/551581/original/file-20231002-21-9nvrqz.JPG?ixlib=rb-1.1.0&rect=0%2C10%2C3456%2C2286&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A general view of Wadi Gharandal riverine wetland, along the Jordan Rift Valley, showing palm trees concentrated at the centre of the wadi near the active spring.</span> <span class="attribution"><span class="source">Mahmoud Abbas</span></span></figcaption></figure><p>Our species, <em>Homo sapiens</em>, migrated out of Africa multiple times – reaching the Levant and Arabia between 130,000 and 70,000 years ago, as exemplified by human fossils and archaeological sites found at various locations. </p>
<p>Little is known, however, about the pathways of these migrations. In a <a href="https://doi.org/10.1126/sciadv.adi6838">study</a> published today in Science Advances, we find the now inhospitable and hyper-arid zone of the southern Jordan Rift Valley was frequently lush and well-watered in the past. </p>
<p>Our evidence suggests this valley had a riverine and wetland zone that would have provided ideal passage for hunter-gatherers as they moved out of Africa and deep into the Levant and Arabia.</p>
<h2>Wandering out of Africa</h2>
<p>Researchers hypothesise humans migrating <a href="https://www.sciencedirect.com/science/article/pii/S0277379116301494">out of Africa</a> would have used platforms in the eastern Sahara, the Nile River Valley, or the margins of the western Red Sea. </p>
<p>From there, these small bands of hunter-gatherers would have passed into the Sinai – a land bridge connecting Africa with the rest of Asia – following migrating animals and hunting a variety of them for sustenance. </p>
<p>For many of these hunter-gatherers, the next stop on the journey would have been the southern portion of the Jordan Rift Valley. This valley is situated in a strategic zone, with the Dead Sea to the north and the Gulf of Aqaba in the south. </p>
<p>Our field work was concentrated on three sites. The first two were <a href="https://www.researchgate.net/publication/344122987_A_wetland_oasis_at_Wadi_Gharandal_spanning_125-70_ka_on_the_human_migration_trail_in_southern_Jordan">Wadi Gharandal</a> and an area near the village of Gregra – both in the valley itself. The third site, <a href="https://livinginjordanasexpat.com/2019/08/21/hiking-wadi-al-hasa-%D9%88%D8%A7%D8%AF%D9%8A-%D8%A7%D9%84%D8%AD%D8%B3%D8%A7/">Wadi Hasa</a>, is located in the more elevated areas of the Jordan plateau. </p>
<p>“Wadi” is an Arabic word describing a temporary riverbed that only contains water during heavy rains.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=550&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=550&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=550&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=691&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=691&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551922/original/file-20231003-21-di5gym.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=691&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">We researched three sites, including two wadis and an area near a village called Gregra.</span>
<span class="attribution"><span class="source">Mahmoud Abbas</span></span>
</figcaption>
</figure>
<h2>When Arabia was a verdant land</h2>
<p>Our goal was to reconstruct the region’s past environmental settings by accurately dating various sections of sediment. We used a technique called luminescence dating to estimate how long sediment grains had been shielded from sunlight, thereby allowing us to calculate how old they were.</p>
<p>Our findings from sedimentary sections ranging 5 to 12 metres in thickness showed ecosystem fluctuations over time, including cycles of dry and humid environments. We also found evidence for the presence of ancient rivers and wetlands.</p>
<p>Luminescence dating showed the sedimentary environments formed between 125,000 and 43,000 years ago, suggesting there had been multiple wet intervals.</p>
<p>At Wadi Gharandal, our team recovered three stone tools associated with a wetland environment. Two of these were made using the <a href="https://link.springer.com/referenceworkentry/10.1007/978-3-319-47829-6_391-1">Levallois method</a> – a characteristic manufacturing technique known to have been used by both Neanderthals and <em>Homo sapiens</em>. We dated the tools to 84,000 years ago. </p>
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<a href="https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551928/original/file-20231004-29-i2gfqe.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">We collected samples for luminescence dating from the Wadi Hasa area in West Jordan. Pictured are Mahmoud Abbas, Mohammed Alqudah and Yuansen Lai.</span>
<span class="attribution"><span class="source">Zhongping Lai/Shantou University</span></span>
</figcaption>
</figure>
<p>Collectively, our fieldwork in the Jordan Rift Valley demonstrates the valley once functioned as a 360-kilometre-long freshwater corridor that helped funnel humans northward into Western Asia and southward into the Arabian Peninsula. </p>
<p>Further evidence for a northward expansion comes from the famous <a href="https://en.wikipedia.org/wiki/Skhul_and_Qafzeh_hominins">Skhul and Qafzeh</a> cave sites in Israel. Fossils of <em>Homo sapiens</em> and Levallois stone tools have been found here. </p>
<p>Towards the south, <a href="https://www.nature.com/articles/s41586-021-03863-;y">fieldwork</a> in northern Saudi Arabia has also demonstrated a network of rivers and lakes was once present in the region. This allowed humans to penetrate a green Nefud Desert replete with savannahs and grassland.</p>
<p>In the heart of the Nefud, the lakeside site of Al Wusta has produced a <a href="https://theconversation.com/our-fossil-finger-discovery-points-to-earlier-human-migration-in-arabia-94670">human fossil and Levallois stone tools</a> dating to 85,000 years ago. These dates coincide with the 84,000-year-old Levallois stone tools found at Wadi Gharandal. </p>
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<h2>Multiple migrations into South-West Asia</h2>
<p>Our findings from the Jordan Rift Valley indicate there were multiple early human migrations from Africa, and into Asia, during favourable conditions. This opposes the <a href="https://www.science.org/content/article/almost-all-living-people-outside-africa-trace-back-single-migration-more-50000-years">theory of a single</a>, rapid wave of human movement out of Africa <a href="https://education.nationalgeographic.org/resource/global-human-journey/">60,000 years ago</a>. </p>
<p>Our results also suggest, together with the Levantine and Arabian evidence, that hunter-gatherers used inland river and wetland systems as they crossed South-West Asia. This contradicts a popular model <a href="https://www.newscientist.com/article/mg18625005-200-humans-took-the-scenic-route-out-of-africa/">suggesting they mainly used</a> coastal routes as super-highways.</p>
<p>Although ancient DNA evidence indicates <em>Homo sapiens</em> interbred with Neanderthals and Denisovans multiple times as they spread into Asia, on-the-ground evidence for these encounters has generally been lacking. Our findings provide further evidence this area served as the ground for these encounters.</p>
<p>Yet numerous questions remain unanswered. Large swathes of territory in South-West Asia have not yet been surveyed or dated – and few fossils of our <a href="https://www.science.org/doi/abs/10.1126/science.aai9067">ancestors have been found</a> to shore up arguments about how early humans really dispersed.</p>
<p>We’ll need to closely investigate more long-neglected areas such as the Jordan Rift Valley to accurately portray how humankind’s voyage out of Africa unfolded. </p>
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<p>
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Read more:
<a href="https://theconversation.com/research-reveals-humans-ventured-out-of-africa-repeatedly-as-early-as-400-000-years-ago-to-visit-the-rolling-grasslands-of-arabia-167050">Research reveals humans ventured out of Africa repeatedly as early as 400,000 years ago, to visit the rolling grasslands of Arabia</a>
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<img src="https://counter.theconversation.com/content/214719/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zhongping Lai receives funding from the China Natural Science Foundation.</span></em></p><p class="fine-print"><em><span>Mahmoud Abbas and Michael Petraglia 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>The findings reveal a close association between climatic conditions and early human migrations out of Africa.Michael Petraglia, Director, Australian Research Centre for Human Evolution, Griffith UniversityMahmoud Abbas, Postdoctoral Research Fellow, Institute of Marine Sciences, Shantou UniversityZhongping Lai, Professor, Institute of Marine Sciences, Shantou UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2102872023-07-26T20:06:11Z2023-07-26T20:06:11ZWho lived at Machu Picchu? DNA analysis shows surprising diversity at the ancient Inca palace<figure><img src="https://images.theconversation.com/files/539453/original/file-20230726-15-h2jmbt.jpeg?ixlib=rb-1.1.0&rect=16%2C0%2C3736%2C2481&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Eddie Kiszka/Pexels</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Standing atop the mountains in the southern highlands of Peru is the 15th-century marvel of the Inca empire, Machu Picchu. Today, the citadel is a global tourist attraction and an icon of precolonial Latin American history – but it was once the royal palace of an emperor.</p>
<p>Our international team of researchers has uncovered the incredible genetic diversity hidden within the ancient remains of those who once called Machu Picchu home. We detail our findings in a study <a href="http://www.science.org/doi/10.1126/sciadv.adg3377">published today</a> in Science Advances.</p>
<h2>The puzzling remnants of a royal site</h2>
<p>The Inca empire once ruled a vast 2 million square km across the breathtaking Andes mountain range in South America. It was formed in 1438 by the first ruler, <a href="https://www.worldhistory.org/Pachacuti_Inca_Yupanqui/">Pachacuti Inca Yupanqui</a>, and reached its height in 1533, before colonisation by the Spanish. </p>
<p>At the heart of the empire was the capital city of Cusco, and nearby was Pachacuti’s majestic palace, Machu Picchu. </p>
<p>Machu Picchu was visited by the royal family and guests during the dry season of May to October as a place to feast, dance, sing and hunt. Although these elite Incas were buried in Cusco upon their death, the palace was maintained year-round by a few hundred servants who lived on site. These servants were buried in cemeteries outside the palace walls.</p>
<p>Following Spanish colonisation, knowledge of Machu Picchu was lost to the Western world – only to be rediscovered by adventurers in the early 20th century. </p>
<p>In 1912, the <a href="https://yalebooks.yale.edu/book/9780913516270/the-1912-yale-peruvian-scientific-expedition-collections-from-machu-picchu/">Yale Peruvian Scientific Expedition</a> documented a staggering count of 174 individuals buried on site. These burials were often shallow graves, or were concealed under large boulders or natural rocky overhangs.</p>
<p>While many lacked grave goods, ceramic artefacts were discovered buried alongside some people. These paint a vivid picture of cultural diversity, with styles from coastal and northern regions of Peru, as well as from the highlands of Bolivia near Lake Titicaca. </p>
<p>This was the first clue that Machu Picchu drew people from all reaches of the Inca empire. It suggested the servants who lived at Machu Picchu came from a variety of places, bringing ceramics from their homelands. </p>
<p>However, the artefacts could have also ended up in the area through trade. To find out where these people had come from, we would have to analyse their DNA.</p>
<h2>New findings from ancient DNA</h2>
<p>We sequenced ancient DNA from the remains of 68 individuals – 34 buried at Machu Picchu and 34 buried in Cusco. Using carbon dating, we dated the remains and found some of these people were buried before the rise of Pachacuti and the Inca empire.</p>
<p>We then compared their DNA with that of Indigenous peoples living in the Andes today (past research has found these genetic lines have continued undisturbed <a href="https://www.cell.com/cell/fulltext/S0092-8674(20)30477-3">for</a> <a href="https://www.pnas.org/doi/pdf/10.1073/pnas.1720798115">the</a> <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8462900/">past</a> <a href="https://www.science.org/doi/10.1126/sciadv.aau4921">2,000</a> <a href="https://europepmc.org/article/MED/31350885">years</a>) – as well as to ancestries from more distant regions of South America. </p>
<p>It’s worth noting these “ancestries” are based on DNA and don’t necessarily overlap with the peoples’ cultural identities, although they sometimes would.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539467/original/file-20230726-15-k5kf9x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">We sequenced ancient DNA from the remains of 68 individuals buried at Machu Picchu and Cusco.</span>
<span class="attribution"><span class="source">The Australian Centre for Ancient DNA/The University of Adelaide</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Were the people buried at Machu Picchu genetically similar to those who had lived in the area since before Pachacuti’s reign? Or were they related to ancestries from more distant regions? </p>
<p>If the latter was true, we could safely assume they (or their parents) had come to Machu Picchu from faraway lands.</p>
<h2>Journeying to a life of servitude</h2>
<p>Of all the DNA samples we analysed, we found 17 individuals had ancestry from one of the distant sources tested (coloured on the map below). These included all regions of the Peruvian coast and highlands, as well as the Amazon regions of Peru, Ecuador and Colombia. </p>
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<a href="https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=558&fit=crop&dpr=1 600w, https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=558&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=558&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=701&fit=crop&dpr=1 754w, https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=701&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/538949/original/file-20230724-25-z31wsu.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=701&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">This map of South America shows different genetic ancestries represented in different regions. The black line shows the full extent of the Inca Empire, while the inset shows Machu Picchu and other royal sites.</span>
<span class="attribution"><a class="source" href="http://www.science.org/doi/10.1126/sciadv.adg3377">Salazar et al., 2023</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Only seven of the buried individuals had ancestry that could be linked to Peru’s vast southern highlands where Machu Picchu and Cusco reside. However, we can’t confirm they were local to Machu Picchu itself.</p>
<p>The remaining 13 individuals had blended ancestry, including from as far away as Brazil and Paraguay. They might have been the offspring of individuals from different lands who met at Machu Picchu – or could be linked to yet unknown South American ancestries. </p>
<p>As for close family relationships, we only discovered one pair: a mother and daughter. </p>
<p>Remarkably, all the individuals were buried together in the major cemeteries, irrespective of their ancestry. This could imply they were considered equal in status to one another, which in turn would suggest they were born elsewhere and arrived at Machu Picchu independently, occasionally forming relationships and having children.</p>
<p>It’s likely these people were from a <a href="https://www.mdpi.com/2073-4425/12/2/215">class of</a> “chosen women” called <em>acllacona</em>, and a similar class of men called <em>yanacona</em>. Individuals in these groups were selected from their homes at a young age and permanently assigned to state, aristocratic or religious service. </p>
<p>After arriving at Machu Picchu, they would have spent the rest of their lives serving the royal estate.</p>
<p>Although we don’t know how much (if any) coercion was involved in the process of these people coming to Machu Picchu, analyses of the bones suggest they lived comfortable lives. Many lived to old age and showed no signs of malnutrition, disease, or injury from warfare or heavy labour.</p>
<h2>A diversity hotspot</h2>
<p>Importantly, the human remains we found that predated the Inca empire did not exhibit high levels of diversity. This suggests it was indeed the establishment of the Inca empire that led people from far and wide to Machu Picchu.</p>
<p>Further, our examination of individuals from Cusco showed less diversity than at Machu Picchu, but more than other regional sites. This is probably because the extensive highland area had a long history of interactions between different peoples before the rise of the Inca empire.</p>
<p>Our findings paint a captivating picture of Machu Picchu as a true hotspot of diversity within the Inca imperial realm – setting it apart as a culturally rich hub within the ancient landscape.</p>
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<img src="https://counter.theconversation.com/content/210287/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roberta Davidson 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>Machu Picchu is now an iconic tourist destination in Peru – but it was once a royal palace that pulled people from all corners of the Inca empire.Roberta Davidson, PhD candidate in Genetic Anthropology, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1939512022-12-26T20:51:52Z2022-12-26T20:51:52ZRituals have been crucial for humans throughout history – and we still need them<figure><img src="https://images.theconversation.com/files/502293/original/file-20221221-16-kz3paq.jpeg?ixlib=rb-1.1.0&rect=62%2C26%2C5898%2C3941&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Each December, Christmas, Hanukkah and Kwanzaa, among others, take over our thoughts and our wallets as we participate in ceremonies our ancestors have practised for as long as we can remember. These are all example of traditions. And in most cases, traditions are accompanied by rituals. </p>
<p>What’s the difference?</p>
<p>In scientific terms, a “tradition” refers to the passing down of customs and beliefs from one generation to the next. A “ritual”, on the other hand, is a series of actions performed according to a prescribed order, and which is often embedded in a larger symbolic system, such as religion or philosophy. </p>
<p>For example, while celebrating birthdays is a tradition, blowing out the candles on a cake is a ritual. Similarly, while getting married is a tradition, exchanging vows is a ritual. </p>
<p>New rituals can be created at any time. To become tradition they only need to be understood and replicated by a wider community. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An old photo from around 1975 shows newlyweds drinking together at their wedding." src="https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=421&fit=crop&dpr=1 600w, https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=421&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=421&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=529&fit=crop&dpr=1 754w, https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=529&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/502295/original/file-20221221-20-fi43dc.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=529&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Communities around the world have different rituals practised during weddings, often passed down through generations.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>And it’s not just in grand gestures that humans practise rituals; some are so embedded into our everyday lives we no longer recognise them. The very particular way someone makes their tea or coffee in the morning is a ritual they enact daily.</p>
<p>Basically, rituals are everywhere. That raises the question: why do we have them at all?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-story-of-legends-families-and-capitalism-a-candid-history-of-the-christmas-tree-196278">A story of legends, families and capitalism: a candid history of the Christmas tree</a>
</strong>
</em>
</p>
<hr>
<h2>Archaeological evidence for the earliest rituals</h2>
<p>Ritual behaviour has very deep origins in humanity. However, tracking these origins and their development is difficult as rituals often leave little or no physical traces behind for archaeologists to find.</p>
<p>Thus far, the best evidence for ancient rituals is the deliberate burial of loved ones. The oldest example is found at Mt Carmel in Israel, where some 130,000 years ago a <a href="https://www.nhm.ac.uk/discover/who-were-the-neanderthals.html">Neanderthal woman</a> was laid to rest by her community. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500553/original/file-20221212-24-83uis7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mt Carmel in Israel is the site of the oldest known human burial. A Neanderthal woman was laid to rest here some 130,000 years ago.</span>
<span class="attribution"><span class="source">Michelle Langley</span></span>
</figcaption>
</figure>
<p>Archaeologists also suggest the extensive use of coloured pigments (particularly bright red) to paint bodies, objects and rock walls points to the practice of “symbolic” behaviour, including ritual. The oldest reliable evidence for colourant use dates to between <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/686484">500,000 and 310,000 years ago</a> and comes from several archaeological sites in southern Africa.</p>
<p>Another type of evidence that is often intrinsically tied to rituals and traditions is musical instruments. Bone flutes dating back to <a href="https://www.livescience.com/20563-ancient-bone-flute.html">about 42,000 years ago</a> have been found in Western Europe. How long people have used the very first instruments – the human voice, clapping hands and stomping feet – remains unknown.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=195&fit=crop&dpr=1 600w, https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=195&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=195&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=244&fit=crop&dpr=1 754w, https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=244&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/502283/original/file-20221221-18-n138xs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=244&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This bone flute, found at the German Palaeolithic site of Hohle Fels, is at least 42,000 years old.</span>
<span class="attribution"><span class="source">Jensen/University of Tubingen</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/who-invented-music-the-search-for-stone-flutes-clay-whistles-and-the-dawn-of-song-185285">Who invented music? The search for stone flutes, clay whistles and the dawn of song</a>
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</em>
</p>
<hr>
<h2>Why do we have rituals?</h2>
<p>Rituals play a very important role in human communities for a number of reasons.</p>
<p>First, rituals help reduce individual and collective anxieties, especially when we ourselves, our family, or our whole community is facing uncertain times or crisis.</p>
<p><a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0431">Research has shown</a> that by praying or singing together we feel connected and supported and our anxiety is reduced. This may explain why Parisians were moved to sing together as they watched their beloved Notre Dame Cathedral burn in 2019.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/323MpjYoQxE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Parisians sing together as Notre Dame burns – a spontaneous ritual to deal with an unexpected crisis.</span></figcaption>
</figure>
<p>Rituals also help reduce anxiety by allowing us to feel control over our surroundings. For instance, new parents may be anxious about protecting their baby. Rituals that welcome the infant into the family and community help them feel they’ve done everything possible – including drawing on supernatural protection – to ensure their child’s wellbeing.</p>
<p>Second, rituals bring people together to celebrate or otherwise mark important life milestones. Births, graduations, marriages and deaths are all marked by rituals and traditions across the globe. These events provide a time and place to gather and encourage people to renew their bonds with friends and family.</p>
<p>These bonds are especially important in times of bad luck, which helps explain why the incentive to maintain them has endured through human history.</p>
<p>Imagine living tens of thousands of years ago, when human communities were much smaller and often lived farther apart. If a volcano erupted, the resulting destruction could mean plant and animal resources – essential food and materials needed for survival – would not be available for months, or perhaps years. </p>
<p>You would then have to rely on the bonds you maintained with neighbouring communities through shared rituals. Such bonds would encourage the sharing of resources until circumstances improve.</p>
<p>Finally, rituals help us remember and share huge amounts of cultural information. By learning a format or pattern of behaviour through ritual, we can absorb information and recall it later more easily. </p>
<p>This approach works astonishingly well to ensure information is passed down orally over long periods. Thus far, the oldest story dated using scientific methods is the Aboriginal Gunditjmara people’s story of the Budj Bim volcano eruption, which occurred <a href="https://www.science.org/content/article/aboriginal-tale-ancient-volcano-oldest-story-ever-told">37,000 years ago</a> in what is now south-western Victoria.</p>
<p>Being able to retain information about changes in the landscape, its plants, animals and people ultimately increased the likelihood that your family would not only survive – but thrive.</p>
<h2>Rituals will remain</h2>
<p>Without rituals, and the traditions in which they become embedded, it is unlikely humanity would have advanced to its current state of cultural and technological development. </p>
<p>We wouldn’t have been able to continually gather and share information, maintain bonds over extensive geographical areas, or make it through difficult periods.</p>
<p>Despite being surrounding by increasingly complex technologies, rituals today remain more important than ever. With extreme weather events and conflicts continuing to displace people all over the globe, they will act as an essential social glue that holds our communities together.</p><img src="https://counter.theconversation.com/content/193951/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michelle Langley is an Associate Professor of Archaeology in the Australian Research Centre for Human Evolution (ARCHE) and the School of Environment and Science at Griffith University.</span></em></p>Rituals have been around for hundreds of thousands of years – but are they still useful today?Michelle Langley, Associate Professor of Archaeology, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1961132022-12-08T19:24:21Z2022-12-08T19:24:21ZDNA from elusive human relatives the Denisovans has left a curious mark on modern people in New Guinea<figure><img src="https://images.theconversation.com/files/499706/original/file-20221208-16-p3m533.jpg?ixlib=rb-1.1.0&rect=301%2C139%2C3309%2C2283&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Derek R. Audette/Shutterstock</span></span></figcaption></figure><p>An encounter with a mysterious and extinct human relative – the Denisovans – has left a mark on the immune traits of modern Papuans, in particular those living on New Guinea Island.</p>
<p>This is a new discovery we describe <a href="https://doi.org/10.1371/journal.pgen.1010470">in a study published in PLoS Genetics</a> today. It further suggests that our modern human diversity didn’t just evolve – some parts of it we got from other, extinct human groups.</p>
<h2>DNA from our evolutionary cousins</h2>
<p>Humans are the only living species of the <em>Homo</em> genus. But until 50,000 years ago, our ancestors coexisted – and sometimes interacted – with multiple other <em>Homo</em> groups across the globe. Most of them we know only by <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/jqs.3137">sparse archaeological remains</a>, which offer tantalising glimpses of our evolutionary cousins.</p>
<p>But for two groups there is something else: DNA. Thanks to technological advances, scientists have retrieved DNA from fossils and sequenced it. As a result, we now have complete genome sequences of the best-known archaic hominins, the <a href="http://www.sciencemag.org/cgi/doi/10.1126/science.1188021">Neanderthals</a>, and a far more elusive group, <a href="http://www.nature.com/articles/nature09710">Denisovans</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fresh-clues-to-the-life-and-times-of-the-denisovans-a-little-known-ancient-group-of-humans-110504">Fresh clues to the life and times of the Denisovans, a little-known ancient group of humans</a>
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<p>Although many Neanderthal fossils have been unearthed all over Europe since they were first identified in the 1860s, the number of known Denisovan fossils fits in the palm of a hand – literally! </p>
<p>The genome sequence we have comes from the smallest bone of a pinky finger. It belonged to the 60,000-year-old remains of a teenage girl from a cave in Siberia, the largest known Denisovan fossil until recently. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The outline of a skeleton finger on a dark surface with a small, orange bone sitting atop one knuckle" src="https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499709/original/file-20221208-16-4pofku.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A museum replica of the Denisovan finger bone used to extract ancient DNA.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Denisova_Phalanx_distalis.jpg">Thilo Parg/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Traces of ancestors</h2>
<p>These genome sequences have transformed the way we think about our extinct relatives. For one, they quickly demonstrated that as humans expanded outside Africa, we had sex – and children – with these other populations.</p>
<p>Traces of their genomes linger in individuals alive today, transmitted across hundreds of generations.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/evolutionary-study-suggests-prehistoric-human-fossils-hiding-in-plain-sight-in-southeast-asia-157587">Evolutionary study suggests prehistoric human fossils 'hiding in plain sight' in Southeast Asia</a>
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<hr>
<p>In the case of Neanderthals, these traces are in all individuals of non-African ancestry today. In the case of Denisovans, we find small traces of their genome in people from all over Asia – especially in Papua New Guinea, and in the island nations of Southeast Asia, where individuals may owe up to 4–5% of their genome to these ancestors. </p>
<p>But identifying these fragments of DNA in our genomes is only the beginning. </p>
<h2>The DNA makes a difference</h2>
<p>The real challenge is to find the biological consequences of this DNA for the people who carry it – which, it bears remembering, is the vast majority of humans. Our specific research question was to pinpoint the molecular processes that might be affected by its presence.</p>
<p>Studies of Neanderthal DNA have shown that genetic variants inherited from them <a href="https://doi.org/10.1093/molbev/msab304">can alter the levels</a> at which some human genes are expressed, for example. We also know Neanderthals have contributed to <a href="https://linkinghub.elsevier.com/retrieve/pii/S0002929715004863">our immune systems</a> (including differences in how people respond to infection with COVID-19), and to <a href="https://www.nature.com/articles/s41467-021-24582-y">variation in skin and hair colour</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-teeth-can-tell-about-the-lives-and-environments-of-ancient-humans-and-neanderthals-104923">What teeth can tell about the lives and environments of ancient humans and Neanderthals</a>
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</p>
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<p>But it has never been clear whether Denisovan DNA has left similar trends in modern humans. </p>
<p>In 2019, <a href="https://www.cell.com/cell/abstract/S0092-8674(19)30218-1">a study revealed</a> the genomic coordinates where Denisovan DNA might be found within the genome of Papuan individuals – that is, the indigenous people of New Guinea Island – alive today.</p>
<p>This led us to begin looking into these regions, to understand the cellular and biological processes that might be affected by Denisovan DNA. We took a hybrid approach to this question, making computational predictions first, and following up with laboratory-based experiments to validate our findings.</p>
<p>In addition, we took advantage of the known Neanderthal DNA within these people to highlight any Denisovan-specific contribution. This gave us a more integrated understanding of how encounters with these relatives left potential biological and evolutionary consequences in modern humans.</p>
<h2>A unique Denisovan contribution</h2>
<p>We noticed that in Papuans, Denisovan and Neanderthal genetic variants both occasionally occur within parts of the genome responsible for modulating the expression levels of nearby genes.</p>
<p>However, only Denisovan variants are consistently predicted to occur and affect elements controlling the expression levels of immune-related genes.</p>
<p>So, these different sources of DNA might contribute to the genetic and phenotypic diversity within Papuans in different ways.</p>
<p>To validate our predictions, we designed an experiment comparing five Denisovan sequences against their modern human counterpart, and tested their ability to actually affect gene expression levels inside a particular kind of immune cell known as a lymphocyte.</p>
<p>In two of the five cases, the Denisovan variants did have a measurably different impact on the gene expression levels than their modern human counterpart. And they impact genes known to be important players in the response to infectious microbes, including viruses. </p>
<p>The fact that Denisovans, but not Neanderthals, seem to have contributed to the immune systems of present-day Papuans, tells us something about these ancient people, too.</p>
<p>Although little is known about how widely through Asia Denisovans lived, it suggests their immune system changed to adapt to the infectious diseases of their environment.</p>
<p>When humans moved in <a href="https://science.sciencemag.org/content/361/6397/88">60,000 years ago</a>, these bits of DNA likely contributed to our success in settling this part of the world.</p>
<p>While our study is the first to elucidate the contribution of Denisovan DNA within modern human genetic diversity, there are still exciting questions to address. In particular, it is not clear whether the overall contributions of Denisovan and Neanderthal genetic variants consistently differ from each other.</p>
<p>It is also important to note we tested genetic variants in immune cells under resting conditions. This means the same or other genetic variants might have different effects out in the environment – this will be an important question for studies in the future.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/first-ever-genetic-analysis-of-a-neanderthal-family-paints-a-fascinating-picture-of-a-close-knit-community-192595">First-ever genetic analysis of a Neanderthal family paints a fascinating picture of a close-knit community</a>
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</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/196113/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Irene Gallego Romero receives funding from the Australian Research Council, the Leakey Foundation, the Chan-Zuckerberg Initiative, the Royal Society of New Zealand and the French National Research Agency</span></em></p><p class="fine-print"><em><span>Davide Vespasiani 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>Humanity carries traces of other populations in our DNA – and a new study shows how one of these ancestors has influenced the immune systems of modern Papuans.Irene Gallego Romero, Senior Lecturer in Human Genetics, The University of MelbourneDavide Vespasiani, Post-doctoral researcher, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1930752022-11-03T12:00:21Z2022-11-03T12:00:21Z8 billion humans: How population growth and climate change are connected as the ‘Anthropocene engine’ transforms the planet<figure><img src="https://images.theconversation.com/files/492902/original/file-20221102-12-nv3d4z.jpg?ixlib=rb-1.1.0&rect=0%2C31%2C5189%2C3410&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Population growth fuels knowledge, leading to new technology and energy use, fueling more population growth. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/commuters-rushing-onto-train-at-umeda-subway-royalty-free-image/521711666">Robert Essel/The Image Bank via Getty Images</a></span></figcaption></figure><p>At first glance, the connections between the world’s growing population and climate change seem obvious. The more people we have on this planet, the larger their collective impact on the climate.</p>
<p>However, a closer look with a longer time horizon reveals relationships between population size and climate change that can help us better understand both humanity’s predicament as the <a href="https://news.un.org/en/story/2022/11/1130417">global population hits 8 billion people</a> – a milestone the <a href="https://ph.news.yahoo.com/baby-girl-born-manila-symbolizes-070929612.html">United Nations marked</a> on Nov. 15, 2022.</p>
<h2>Looking back to the Stone Age</h2>
<p>For much of human evolution, our ancestors were exposed to large climatic fluctuations between ice ages and intermittent warmer periods. The last of these ice ages <a href="https://en.wikipedia.org/wiki/Ice_age">ended about 10,000 years ago</a>. </p>
<p>Before the ice sheets melted, sea levels were <a href="https://www.usgs.gov/media/images/coastline-eastern-us-changesslowly">about 400 feet (120 meters) lower than today</a>. That allowed humans to migrate around the world. Everywhere they went, our ancestors reshaped landscapes, first by clearing forests and then through early agricultural practices that emerged in a number of regions starting just as the last ice age ended.</p>
<p>Paleoclimatologist <a href="https://evsc.as.virginia.edu/people/profile/wfr5c">William Ruddiman</a> has suggested that these early actions – cutting down trees and expanding farming – caused a small initial rise in carbon dioxide in the atmosphere. That <a href="https://www.globalpolicyjournal.com/blog/24/02/2021/ruddiman-hypothesis-debated-theory-progresses-along-interdisciplinary-lines">contributed to a stable climate</a> over the past 10,000 years by counteracting trends of declining carbon dioxide levels that might have triggered another glaciation event. </p>
<figure class="align-center ">
<img alt="Painting from an Egyptian tomb showing a person holding a scythe and cutting wheat." src="https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=523&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=523&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=523&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=657&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=657&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492904/original/file-20221102-28600-bw9n55.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=657&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Agriculture began fueling the Anthropocene engine. A painting in the tomb of Sennedjem from Egypt’s 19th dynasty, between 1295 B.C. and 1186 B.C., shows a person reaping wheat in Thebes.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/detail-of-a-painting-on-stucco-in-the-tomb-of-sennedjem-news-photo/152198532">Werner Forman/Universal Images Group/Getty Images</a></span>
</figcaption>
</figure>
<p>By reshaping landscapes, our ancestors actively constructed the niches they inhabited. This process is an important aspect of evolutionary change, <a href="https://doi.org/10.1002/jez.b.22631">creating important feedback dynamics</a> between evolving species and their environment.</p>
<p>As humans evolved, the demands of the growing population, associated knowledge creation and energy use created a <a href="https://technosphere-magazine.hkw.de/p/The-Growth-and-Differentiation-of-Metabolism-Extended-Evolutionary-Dynamics-in-the-Technosphere-hTBDuetUoDLXpZLjWAq4aX">feedback cycle</a> my colleagues and I call the Anthropocene engine. That engine has transformed the planet.</p>
<h2>Revving up the Anthropocene engine</h2>
<p>The Anthropocene engine has been running for at least 8,000 years. It led to the rise of modern civilizations and ultimately to the environmental challenges we face today, including climate change.</p>
<p>How does the Anthropocene engine work?</p>
<p>First, populations had to reach a critical number of people to successfully create enough knowledge about their environments that they could begin to actively and purposefully transform the niches they lived in.</p>
<p>Successful agriculture was the product of such knowledge. In turn, agriculture increased the amount of energy available to these early societies.</p>
<figure class="align-center ">
<img alt="A carved scene shows a shop with bowls on the wall, a man pounding an item with a large hammer, another person writing, a dog and a child." src="https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492907/original/file-20221102-26775-6l91zv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">More knowledge and energy led to division of labor and more innovation. This marble relief depicts a coppersmith’s shop in Pompei during the first century.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/roman-civilization-1st-century-a-d-pompei-marble-relief-news-photo/122222124">DEA/L. Pedicini/De Agostini via Getty Images</a></span>
</figcaption>
</figure>
<p>More energy supports more people. More people led to early settlements and, later, to cities. This allowed for task specialization and division of labor, which, in turn, accelerated the creation of more knowledge, which increased available energy and allowed population size to grow as well. And so on, and so on. </p>
<p>While the details of this process differ around the world, they are all driven by the same Anthropocene engine.</p>
<h2>The problem of exponential growth</h2>
<p>As an <a href="https://scholar.google.com/citations?hl=en&user=N5P-cI4AAAAJ&view_op=list_works&sortby=pubdate">evolutionary biologist and historian of science</a>, I have studied the evolution of knowledge and complexity for over three decades and have been <a href="https://doi.org/10.48550/arXiv.2112.05876">developing mathematical models</a> with colleagues <a href="https://doi.org/10.1371/journal.pone.0058407">to help explain these</a> <a href="https://doi.org/10.1126/science.276.5309.122">processes</a>. Using the universality of the underlying processes driving the Anthropocene engine, we can capture these dynamics in the form of a <a href="https://www.youtube.com/watch?v=Y6QLenwsOEs&t=383s">growth equation</a>, which includes links between population growth and increasing energy use.</p>
<iframe src="https://ourworldindata.org/grapher/population?country=~OWID_WRL" loading="lazy" style="width: 100%; height: 600px; border: 0px none;" width="100%" height="400"></iframe>
<p>One consequence of positive feedback cycles in dynamical systems is that they lead to exponential growth.</p>
<p>Exponential growth can start very slowly and be barely noticeable for quite some time. But eventually it will have dramatic consequences wherever resources are limited.</p>
<p>Driven by the Anthropocene engine, human population has grown exponentially, and individual societies have <a href="https://doi.org/10.1073/pnas.1114845109">approached collapse</a> multiple times over the past 8,000 years. The disappearance of the Easter Island civilization and the <a href="https://hmsc.harvard.edu/file/1053329">collapse of the Mayan empire</a>, for example, have been linked to the depletion of environmental resources as populations rose. The dramatic decline of the European population during the <a href="https://www.nature.com/articles/s41586-022-04800-3">Black Death in the 1300s</a> was a direct consequence of crowded and unsanitary living conditions that facilitated the spread of <em>Yersenia pestis</em>, or plague.</p>
<p>Biologist Paul Ehrlich warned about unchecked growth in his 1968 book “<a href="https://theconversation.com/a-long-fuse-the-population-bomb-is-still-ticking-50-years-after-its-publication-96090">The Population Bomb</a>,” predicting growing global demand for limited resources would lead to societal collapse without changes in human consumption.</p>
<p>But globally, humanity has always found a way to avoid doom. Knowledge-based innovations, such as the <a href="https://en.wikipedia.org/wiki/Green_Revolution">Green Revolution</a> – the broad-scale effects of which Ehrlich did not foresee – have enabled people to reset the clock, leading to more cycles of innovation and (almost) collapse. </p>
<figure class="align-center ">
<img alt="An illustration of a row of giant furnaces with steam coming out, rail cars carrying coal and a stream engine, with workers scurrying about." src="https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=556&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=556&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=556&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=699&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=699&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492905/original/file-20221102-20-msahko.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=699&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Fossil fuels and the Industrial Revolution changed the face of Britain and the Western world in the span of a few decades starting in the late 1700s.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-industrial-revolution-age-of-steel-blast-furnaces-by-news-photo/1053836066">Hulton Archive/Getty Images</a></span>
</figcaption>
</figure>
<p>One example is the sequence of energy regimes. It started with wood and animal power. Then came coal, oil and gas.</p>
<p>Fossil fuels powered the Industrial Revolution, and with it, greater wealth and advances in health care. But the age of fossil fuels has had dramatic consequences. It almost doubled the concentration of carbon dioxide in the atmosphere in less than 300 years, causing the unprecedented speed of global warming that humanity is experiencing today. </p>
<p>At the same time, inequality has become endemic. Poorer nations that contributed little to climate change are suffering the most from global warming, while just 20 wealthier countries are <a href="https://www.oecd.org/tax/g20-economies-are-pricing-more-carbon-emissions-but-stronger-globally-more-coherent-policy-action-is-needed-to-meet-climate-goals-says-oecd.htm">responsible for about 80%</a> of emissions.</p>
<iframe src="https://ourworldindata.org/explorers/climate-change?time=-400000..latest&facet=none&hideControls=true&Metric=CO%E2%82%82+concentrations&Long-run+series%3F=true&country=~OWID_WRL" loading="lazy" style="width: 100%; height: 600px; border: 0px none;" width="100%" height="400"></iframe>
<p>The next energy transition to avoid collapse is underway now with the rise of renewable energy sources like wind and solar power. But <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-3/">studies</a> – including a report released ahead of the <a href="https://cop27.eg/#/">2022 U.N. Climate Change Conference</a> in November – <a href="https://www.unep.org/resources/emissions-gap-report-2022">show</a> humans aren’t evolving their energy use fast enough to keep climate change in check.</p>
<h2>Using knowledge to reset the cycle again</h2>
<p>Every species, if left unchecked, would grow exponentially. But species are subject to constraints – or negative feedback mechanisms – such as predators and limited food supplies.</p>
<p>The Anthropocene engine has allowed humans to emancipate ourselves from many of the negative feedback mechanisms that otherwise would have kept the population’s growth in check. We intensified food production, developed trade among regions and discovered medications to survive diseases. </p>
<p>Where does this leave humanity now? Are we approaching inevitable collapse from climate change of our own making, or can we transition again and discover innovations that reset the cycle?</p>
<p>Introducing negative feedback into our socioeconomic-technical systems – not as radical population control or war, but in the form of norms, values and regulations on excess greenhouse gas emissions – can help keep climate change in check. </p>
<p>Humanity can use knowledge to keep itself within its environmental boundaries.</p>
<p><em>This article was updated Nov. 15, 2022, to reflect the population passing 8 billion.</em></p><img src="https://counter.theconversation.com/content/193075/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Manfred Laubichler receives funding from The National Science Foundation. He is affiliated with the Santa Fe Institute, the Max Planck Institute for the History of Science, the Complexity Science Hub, Vienna, and the Global Climate Forum. </span></em></p>The UN estimates the global population will pass 8 billion people on Nov. 15, 2022. From the Stone Age to today, here’s how things spiraled out of control.Manfred Laubichler, Global Futures Professor and President’s Professor of Theoretical Biology and History of Biology, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1925952022-10-19T19:05:47Z2022-10-19T19:05:47ZFirst-ever genetic analysis of a Neanderthal family paints a fascinating picture of a close-knit community<figure><img src="https://images.theconversation.com/files/489930/original/file-20221017-17-4qvy1b.jpg?ixlib=rb-1.1.0&rect=11%2C0%2C1243%2C718&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Neanderthal father and his daughter.</span> <span class="attribution"><span class="source">Tom Björklund</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Our closest evolutionary relatives, the Neanderthals (<em>Homo neanderthalensis</em>), were once spread across Europe and as far east as the Altai Mountains in southern Siberia.</p>
<p>Yet more than 160 years since the first Neanderthal fossils were unearthed in Europe, little is known about the group size or social organisation of Neanderthal communities.</p>
<p>Using ancient DNA, a <a href="https://www.nature.com/articles/s41586-022-05283-y">new study</a> provides a snapshot of a Neanderthal community frozen in time.</p>
<p>With our colleagues, we show a group of Neanderthals living in the Altai foothills around 54,000 years ago consisted of perhaps 10 to 20 individuals. Many of them were closely related – including a father and his young daughter.</p>
<h2>The easternmost Neanderthals</h2>
<p>The first genetic clues to Neanderthals were obtained <a href="https://www.cell.com/fulltext/S0092-8674(00)80310-4">25 years ago</a> from a fragment of mitochondrial DNA, which is found in cell structures called mitochondria rather than in the cell nucleus.</p>
<p>Subsequent mitochondrial DNA studies and genome-wide nuclear data from 18 individuals have sketched the broad brushstrokes of Neanderthal history, revealing the existence of many genetically distinct groups between about 430,000 and 40,000 years ago.</p>
<p>Our new study is the first to analyse ancient DNA from the teeth and bones of multiple Neanderthals who lived at around the same time. The fossils came from archaeological excavations of Okladnikov Cave in the mid-1980s and Chagyrskaya Cave since 2007.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map showing locations of the caves and a photo of one of them" src="https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=431&fit=crop&dpr=1 754w, https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=431&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/489936/original/file-20221017-12-8falkc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=431&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Neanderthal DNA was sequenced from fossil remains found at Chagyrskaya Cave (photo) and Okladnikov Cave in southern Siberia.</span>
<span class="attribution"><span class="source">Maciej Krajcarz (map) and Richard Roberts (photo)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>These caves were used by Neanderthals as hunting camps. The remains of animals such as bison and horses are abundant, and more than 80 Neanderthal fossils were also found in Chagyrskaya Cave – one of the largest such collections anywhere in the world.</p>
<p>Both sites also contain <a href="https://www.pnas.org/doi/10.1073/pnas.1918047117">distinctive stone tools</a> that bear a striking resemblance to artefacts found at Neanderthal sites in central and eastern Europe.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/stone-tools-reveal-epic-trek-of-nomadic-neanderthals-129886">Stone tools reveal epic trek of nomadic Neanderthals</a>
</strong>
</em>
</p>
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<h2>Family ties</h2>
<p>To paint a detailed picture of the genetic makeup and relatedness of these Neanderthals, we analysed mitochondrial DNA (which is passed down the female line), Y-chromosomes (passed from father to son) and genome-wide data (inherited from both parents) for 17 Neanderthal fossils – the most ever sequenced in a single study.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A range of bones and teeth on a dark background" src="https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=278&fit=crop&dpr=1 600w, https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=278&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=278&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=350&fit=crop&dpr=1 754w, https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=350&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/489916/original/file-20221017-25-a1wd6b.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=350&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Neanderthal teeth and bones from Chagyrskaya Cave (A, B) and Okladnikov Cave (C) included in our study. The white bar in each panel is 1 cm in length.</span>
<span class="attribution"><span class="source">Bence Viola</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The teeth and bones came from 13 individuals: 11 from Chagyrskaya Cave and two from Okladnikov Cave. Seven of the Neanderthals were male and six were female. Eight were adults and five were children or adolescents.</p>
<p>Among them were the remains of a Neanderthal father and his teenage daughter, as well as a pair of second-degree relatives – a young boy and an adult female, perhaps his cousin, aunt or grandmother.</p>
<p>Although the nearby site of <a href="https://theconversation.com/fresh-clues-to-the-life-and-times-of-the-denisovans-a-little-known-ancient-group-of-humans-110504">Denisova Cave</a> was inhabited by Neanderthals from as early as 200,000 years ago, the Chagyrskaya and Okladnikov Neanderthals are more closely related to European Neanderthals than to the earlier ones at Denisova Cave.</p>
<p>This finding is consistent with a <a href="https://www.pnas.org/doi/10.1073/pnas.2004944117">previous genomic study</a> of a Chagyrskaya Neanderthal and the presence of distinctive stone tools at Chagyrskaya and Okladnikov Caves that closely resemble those found at Neanderthal sites in Europe.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graph showing relations among the various species" src="https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=643&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=643&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=643&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=808&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=808&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490089/original/file-20221017-7429-yw50nu.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=808&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Phylogenetic tree of mitochondrial DNA sequences showing the evolutionary relationships among the Chagyrskaya (blue) and Okladnikov (orange) Neanderthals included in our study, Neanderthals from Denisova Cave and Europe, and present-day humans from Africa, East Asia and Europe.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We also found the Chagyrskaya Neanderthals share several heteroplasmies – a special kind of mitochondrial DNA variant that typically persists for less than three generations.</p>
<p>Taken together with the evidence for their close family connections, these indicate the Chagyrskaya Neanderthals must have lived – and died – at around the same time.</p>
<h2>On the brink of extinction</h2>
<p>Our analyses also revealed this Neanderthal community had extremely low genetic diversity – consistent with a group size of just 10 to 20 people.</p>
<p>This is much smaller than the genetic diversity recorded for any ancient or present-day human community, and is more like that found among endangered species at risk of extinction, such as <a href="https://www.worldwildlife.org/species/mountain-gorilla">mountain gorillas</a>.</p>
<p>The Chagyrskaya Neanderthals were not a community of hermits, however. We discovered their mitochondrial DNA diversity was much higher than their Y-chromosome diversity, which can be explained by the predominance of female (rather than male) migration between Neanderthal communities.</p>
<p>Did these migrations involve Denisovans, who occupied Denisova Cave repeatedly from at least 250,000 years ago to around 50,000 years ago?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dirty-secrets-sediment-dna-reveals-a-300-000-year-timeline-of-ancient-and-modern-humans-living-in-siberia-161585">Dirty secrets: sediment DNA reveals a 300,000-year timeline of ancient and modern humans living in Siberia</a>
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<p>Denisovans are a sister group to Neanderthals and they interbred at least once. This happened around 100,000 years ago, <a href="https://www.nature.com/articles/d41586-018-06004-0">producing a daughter</a> from a Neanderthal mother and a Denisovan father.</p>
<p>Yet even though Denisovans were present at Denisova Cave at around the same time as the Neanderthals living at Chagyrskaya and Okladnikov Caves, we found no evidence for Denisovan gene flow into these Neanderthals in the 20,000 years leading up to their demise.</p>
<h2>Kindred spirits</h2>
<p>In recent years, multiple lines of evidence have shown Neanderthals possessed <a href="https://theconversation.com/neanderthals-were-no-brutes-research-reveals-they-may-have-been-precision-workers-103858">technical skills</a>, <a href="https://theconversation.com/how-we-discovered-that-neanderthals-could-make-art-92127">cognitive capabilities</a> and <a href="https://www.nature.com/articles/s41559-021-01487-z">symbolic behaviours</a> as impressive as those of our ancient <em>Homo sapiens</em> ancestors.</p>
<p>Our genetic insights add a new social dimension to this picture. They provide a rare glimpse into the close-knit family structure of a Neanderthal community eking out an existence on the eastern frontier of their geographic range, close to the time when their species finally died out.</p><img src="https://counter.theconversation.com/content/192595/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard 'Bert' Roberts receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Laurits Skov 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>Ancient DNA from Neanderthal fossils in southern Siberia reveals a small community with close family ties – including a father and his teenage daughter.Laurits Skov, Postdoctoral research associate, Max Planck Institute for Evolutionary AnthropologyRichard 'Bert' Roberts, Director, ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH), University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1792902022-05-17T20:00:28Z2022-05-17T20:00:28ZA fossil tooth places enigmatic ancient humans in Southeast Asia<figure><img src="https://images.theconversation.com/files/459634/original/file-20220426-22-rl38zi.JPG?ixlib=rb-1.1.0&rect=0%2C16%2C7491%2C2784&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Fabrice Demeter (University of Copenhagen / CNRS Paris)</span>, <span class="license">Author provided</span></span></figcaption></figure><p>What do a finger bone and some teeth found in the frigid Denisova Cave in Siberia’s Altai mountains have in common with fossils from the balmy hills of tropical northern Laos? </p>
<p>Not much, until now: in a Laotian cave, an international team of researchers including ourselves has <a href="https://www.nature.com/articles/s41467-022-29923-z">discovered a tooth</a> belonging to an ancient human previously only known from icy northern latitudes – a Denisovan.</p>
<p>The find shows these long-lost relatives of <em>Homo sapiens</em> inhabited a wider area and range of environments than we previously knew, confirming hints found in the DNA of modern human populations from Southeast Asia and Australasia.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fresh-clues-to-the-life-and-times-of-the-denisovans-a-little-known-ancient-group-of-humans-110504">Fresh clues to the life and times of the Denisovans, a little-known ancient group of humans</a>
</strong>
</em>
</p>
<hr>
<h2>Who were the Denisovans?</h2>
<p>Little is known about these distant cousins of modern humans, except that they once lived in Asia, were related to and interacted with the better-known Neanderthals, and are now extinct. </p>
<p>The first traces of Denisovans were only found in 2010, with the <a href="https://www.nature.com/articles/nature09710">discovery</a> of an innocuous finger bone in remote Denisova Cave. The extreme cold of the cave meant some ancient DNA was preserved in the bone – and the DNA revealed the finger had belonged to an unknown species of human.</p>
<p>This discovery changed the course of human evolutionary studies, and the newly discovered humans were named Denisovans after the cave where the fossil was found.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461151/original/file-20220504-14-lmc80h.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">
<figcaption>
<span class="caption">The first traces of the Denisovans were found at Denisova Cave in Siberia in 2010.</span>
<span class="attribution"><span class="source">Mike Morley (Flinders University)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Fossilised teeth from Denisovans were <a href="https://www.pnas.org/doi/abs/10.1073/pnas.1519905112">later discovered</a> in the <a href="https://www.science.org/doi/10.1126/science.aam9695">same cave</a>. Two upper and one lower molar were found in sediments that were dated to between 195,000 and 52,000 years ago. </p>
<p>Meanwhile, it was found that <a href="https://www.nature.com/articles/nature09710">genes from Denisovans survived</a> in modern day people from Southeast Asia and Australasia. This implied that the Denisovans had dispersed over a far larger area than anticipated. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/evolutionary-study-suggests-prehistoric-human-fossils-hiding-in-plain-sight-in-southeast-asia-157587">Evolutionary study suggests prehistoric human fossils 'hiding in plain sight' in Southeast Asia</a>
</strong>
</em>
</p>
<hr>
<h2>The hunt for more fossils</h2>
<p>The hunt was on to find more evidence of these humans outside Russia, but scientists had no idea what they actually looked like. For the first time in history we knew more about a human’s DNA than their anatomy!</p>
<p>The next twist came when a <a href="https://www.nature.com/articles/s41586-019-1139-x">160,000-year-old Denisovan jawbone</a> surfaced on the Tibetan Plateau, giving the scientific community a tantalising glimpse of what the bodies of these ancient humans were like and where they lived. </p>
<p>But questions remained: just how far did they spread in Asia, and how did their genetic imprint survive in Southeast Asians and Australasians? </p>
<p>Clearly Denisovans could live in the cold environments of Siberia and Tibet, but could they have also occupied a completely different ecological niche and adapted to a tropical climate?</p>
<h2>Tam Ngu Hao 2 (Cobra Cave)</h2>
<p>Enter a new cave found by an international (Laos–French–American–Australian) team in northern Laos in 2018, close to the famous Tam Pa Ling cave where 70,000-year-old <a href="https://www.pnas.org/doi/10.1073/pnas.1208104109">modern human fossils</a> were found. </p>
<p>The site, named Tam Ngu Hao 2 (or Cobra Cave), was found high up in the limestone mountains and contained remnants of old cave sediment packed with fossils.</p>
<p>The cave sediments contained teeth from giant herbivores, such as ancient elephants and rhinos that liked to live in woodland environments. The teeth were likely washed into the cave during a flooding event that deposited the sediments and fossils. </p>
<p>These sediments were covered by a layer of very hard rock called flowstone, which is formed by water flowing over the cave floor. The sediments and fossils were dated by this study to provide an age for the time of deposition in the cave, and by association a minimum age for the death of the animals.</p>
<h2>A young girl’s tooth</h2>
<p>A human tooth (a lower permanent molar) was found in the cave sediments, but we could not initially identify what species of human it came from. The humid conditions in Laos meant that the ancient DNA was not preserved. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=686&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=686&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=686&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=862&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=862&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461153/original/file-20220504-13-li3i3m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=862&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This tooth likely belonged to a young Denisovan girl who lived around 150,000 years ago.</span>
<span class="attribution"><span class="source">Fabrice Demeter (University of Copenhagen / CNRS Paris)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We did however find ancient proteins that suggested the tooth came from a young, likely female, human – probably between 3.5 and 8.5 years old. </p>
<p>After very detailed analysis of the shape of this tooth, our team identified many similarities to the Denisovan teeth found on the Tibetan Plateau. This suggested the tooth’s owner was most likely a Denisovan who lived between 164,000 and 131,000 years ago in the warm tropics.</p>
<h2>An ancient human hotspot</h2>
<p>This fossil represents the first discovery of Denisovans in Southeast Asia, and shows that Denisovans were at least as far south as Laos. This is in agreement with the genetic evidence found in modern day Southeast Asian populations. </p>
<p>They may have been just at home in the balmy tropical climates of Laos as the icy conditions of northern Europe and the high-altitude environments of the Tibetan Plateau. This suggests the Denisovans were very good at adapting to diverse environments. </p>
<p>It would seem that Southeast Asia was a hotspot of diversity for humans. At least five different species set up camp there at different times: <em>Homo erectus</em>, the Denisovans/Neanderthals, <em>Homo floresiensis</em>, <em>Homo luzonensis</em>, and <em>Homo sapiens</em>. </p>
<p>How many of these species overlapped and interacted? Another fossil discovered in the dense network of Southeast Asian caves could provide the next clue to understanding these complex relationships.</p><img src="https://counter.theconversation.com/content/179290/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kira Westaway receives funding from the Australian Research Council (ARC) and the Leakey Foundation</span></em></p><p class="fine-print"><em><span>Mike W Morley receives funding from the Australian Research Council (ARC). </span></em></p><p class="fine-print"><em><span>Renaud Joannes-Boyau receives funding from the Australian Research Council (ARC).</span></em></p>The mysterious Denisovans left DNA traces in populations across Southeast Asia and Australasia, but until now no physical signs of their presence outside Eurasia had been found.Kira Westaway, Associate professor, Macquarie UniversityMike W. Morley, Associate Professor, Flinders UniversityRenaud Joannes-Boyau, Associate Professor, Southern Cross UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1754362022-02-23T16:03:13Z2022-02-23T16:03:13ZAncient DNA helps reveal social changes in Africa 50,000 years ago that shaped the human story<figure><img src="https://images.theconversation.com/files/446822/original/file-20220216-3870-1o2qb6l.jpg?ixlib=rb-1.1.0&rect=186%2C0%2C3661%2C2475&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Together with artifacts from the past, ancient DNA can fill in details about our ancient ancestors.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Kondoa_Irangi_Rock_Paintings_(51507918388).jpg">Nina R/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Every person alive on the planet today is descended from people who lived as hunter-gatherers in Africa. </p>
<p>The continent is the cradle of <a href="https://theconversation.com/how-a-handful-of-prehistoric-geniuses-launched-humanitys-technological-revolution-171511">human origins and ingenuity</a>, and <a href="https://theconversation.com/archaeological-discoveries-are-happening-faster-than-ever-before-helping-refine-the-human-story-128743">with each new fossil and archaeological discovery</a>, we learn more about our shared African past. Such research tends to focus on when our species, <em>Homo sapiens</em>, <a href="https://www.scientificamerican.com/article/how-homo-sapiens-became-the-ultimate-invasive-species/">spread out to other landmasses 80,000-60,000 years ago</a>. But what happened in Africa after that, and why don’t we know more about the people who remained?</p>
<p>Our 2022 study, conducted by an interdisciplinary team of 44 researchers based in 12 countries, <a href="https://www.nature.com/articles/s41586-022-04430-9">helps answer these questions</a>. By sequencing and analyzing ancient DNA (aDNA) from people who lived as long ago as 18,000 years, we roughly doubled the age of sequenced aDNA from sub-Saharan Africa. And this genetic information helps <a href="https://scholar.google.com/citations?user=GlrnQDgAAAAJ&hl=en&oi=ao">anthropologists</a> <a href="https://scholar.google.com/citations?user=MQkcYDYAAAAJ&hl=en&oi=ao">like</a> <a href="https://scholar.google.com/citations?user=3QKcZMoAAAAJ&hl=en&oi=ao">us</a> understand more about how modern humans were moving and mingling in Africa long ago.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="View from above of archaeological excavation" src="https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441914/original/file-20220121-8326-sxvlib.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">People took shelter in natural rock overhangs, leaving behind an archaeological record of their daily activities – and sometimes their graves. By digging carefully, archaeologists can connect information from aDNA to information about the social lives of these people.</span>
<span class="attribution"><span class="source">Jacob Davis</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tracing our human past in Africa</h2>
<p><a href="https://theconversation.com/new-moroccan-fossils-suggest-humans-lived-and-evolved-across-africa-100-000-years-earlier-than-we-thought-78826">Beginning about 300,000 years ago</a>, people in Africa who looked like us – the earliest anatomically modern humans – also started behaving in ways that seem very human. They made <a href="https://www.smithsonianmag.com/science-nature/how-drastic-ecological-change-led-leap-forward-behavior-weapons-and-tools-180976101/">new kinds of stone tools and began transporting raw materials</a> up to 250 miles (400 kilometers), likely through trade networks. By 140,000-120,000 years ago, people made <a href="https://scitechdaily.com/early-humans-used-bone-tools-to-produce-clothing-in-morocco-120000-years-ago/">clothing from animal skins</a> and began to <a href="https://www.smithsonianmag.com/smart-news/worlds-oldest-jewelry-discovered-in-moroccan-cave-180978766/">decorate themselves with pierced marine shell beads</a>. </p>
<p>While early innovations appeared in a patchwork fashion, a more widespread shift happened around 50,000 years ago – around the same time that people started <a href="https://www.nationalgeographic.com/history/article/australia-aboriginal-early-human-evolution-spd">moving into places as distant as Australia</a>. New types of stone and bone tools became common, and people began <a href="https://theconversation.com/the-tiny-ostrich-eggshell-beads-that-tell-the-story-of-africas-past-128577">fashioning and exchanging ostrich eggshell beads</a>. And while most <a href="https://theconversation.com/an-ancient-san-rock-art-mural-in-south-africa-reveals-new-meaning-157177">rock art in Africa</a> is undated and badly weathered, an increase in <a href="https://theconversation.com/what-the-use-of-ochre-tells-us-about-the-capabilities-of-our-african-ancestry-47081">ochre pigment at archaeological sites</a> hints at an explosion of art. </p>
<p>What caused this shift, known as the <a href="https://en.wikipedia.org/wiki/Late_Stone_Age">Later Stone Age</a> transition, has been a longstanding archaeological mystery. Why would certain tools and behaviors, which up until that point had appeared in a piecemeal way across Africa, suddenly become widespread? Did it have something to do with changes in the number of people, or how they interacted? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Nine disc-shaped beads" src="https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=474&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=474&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=474&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=596&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=596&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441913/original/file-20220121-9541-bx79fs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=596&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Beads made from ostrich eggshell were hot trade items and can show the extent of ancient social networks.</span>
<span class="attribution"><span class="source">Jennifer Miller</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>The challenge of accessing the deep past</h2>
<p>Archaeologists reconstruct human behavior in the past mainly through things people left behind – remains of their meals, tools, ornaments and <a href="https://theconversation.com/how-we-discovered-the-oldest-human-burial-in-africa-and-what-it-tells-us-about-our-ancestors-160122">sometimes even their bodies</a>. These records may accumulate over thousands of years, creating views of daily livelihoods that are really averages over long periods of time. However, it’s hard to study ancient demography, or how populations changed, from the archaeological record alone. </p>
<p>This is where DNA can help. When combined with evidence from archaeology, linguistics and oral and written history, scientists can piece together how people moved and interacted based on which groups share genetic similarities.</p>
<p>But DNA from living people can’t tell the whole story. African populations have been transformed over the past 5,000 years by the <a href="https://theconversation.com/ancient-dna-is-revealing-the-origins-of-livestock-herding-in-africa-114387">spread of herding and farming</a>, the <a href="https://theconversation.com/how-we-recreated-a-lost-african-city-with-laser-technology-92852">development of cities</a>, <a href="https://theconversation.com/archaeology-shows-how-ancient-african-societies-managed-pandemics-138217">ancient pandemics</a> and the ravages of <a href="https://theconversation.com/a-digital-archive-of-slave-voyages-details-the-largest-forced-migration-in-history-74902">colonialism and slavery</a>. These processes caused <a href="https://www.nytimes.com/2020/02/12/science/west-africa-ancient-humans.html">some lineages to vanish</a> and <a href="https://theconversation.com/mitochondrial-dna-reveals-unexpected-ancestral-connections-122053">brought others together</a>, forming new populations. </p>
<p>Using present-day DNA to reconstruct ancient genetic landscapes is like reading a letter that was left out in the rain: some words are there but blurred, and some are gone completely. Researchers need ancient DNA from archaeological human remains to explore human diversity in different places and times and to understand what factors shaped it.</p>
<p>Unfortunately, aDNA from Africa is particularly hard to recover because the continent straddles the equator and heat and humidity degrade DNA. While the <a href="https://www.scientificamerican.com/article/oldest-ancient-human-dna-details-dawn-of-neandertals/">oldest aDNA from Eurasia is roughly 400,000 years old</a>, all sequences from sub-Saharan Africa to date have been younger than around 9,000 years. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map with markers showing distribution of ancient DNA data in Africa, and the world." src="https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=625&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=625&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=625&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=785&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=785&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444879/original/file-20220207-47158-11n9ym1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=785&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Map of all published ancient genomes, with black dots scaled to the number of individuals’ genomes. Blue dots indicate Later Stone Age foragers comparable to those in our study. Red stars indicate individuals reported for the first time in our study. Inset map underscores the gap between Africa and other parts of the world in terms of published ancient genomes. Ancient DNA preserved between the Tropics of Cancer and Capricorn is rare.</span>
<span class="attribution"><span class="source">Mary Prendergast; basemaps by Natural Earth</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Breaking the ‘tropical ceiling’</h2>
<p>Because each person carries genetic legacies inherited from generations of their ancestors, our team was able to use DNA from individuals who lived between 18,000-400 years ago to explore how people interacted as far back as the last 80,000-50,000 years. This allowed us, for the first time, to test whether demographic change played a role in the Later Stone Age transition. </p>
<p><a href="https://www.nature.com/articles/s41586-022-04430-9">Our team sequenced aDNA</a> from six individuals buried in what are now Tanzania, Malawi and Zambia. We compared these sequences to previously studied aDNA from 28 individuals buried at sites stretching from Cameroon to Ethiopia and down to South Africa. We also generated new and improved DNA data for 15 of these people, trying to extract as much information as possible from the small handful of ancient African individuals whose DNA is preserved well enough to study.</p>
<p>This created the largest genetic dataset so far for studying the population history of ancient African foragers – people who hunted, gathered or fished. We used it to explore population structures that existed prior to the sweeping changes of the past few thousand years.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Museum building, palm trees" src="https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444614/original/file-20220205-23-d1055k.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">National Museum of Tanzania in Dar es Salaam. Ancient DNA studies in Africa are made possible by the efforts of curators to protect and preserve remains in tropical conditions.</span>
<span class="attribution"><span class="source">Mary Prendergast</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>DNA weighs in on a longstanding debate</h2>
<p>We found that people did in fact change how they moved and interacted around the Later Stone Age transition.</p>
<p>Despite being separated by thousands of miles and years, all the ancient individuals in this study were descended from the same three populations related to ancient and present-day eastern, southern and central Africans. The presence of eastern African ancestry as far south as Zambia, and southern African ancestry as far north as Kenya, indicates that people were moving long distances and having children with people located far away from where they were born. The only way this population structure could have emerged is if people were moving long distances over many millennia. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Lush African landscape" src="https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/446008/original/file-20220211-21-gafkub.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">Genetic data now suggests that people moved and mingled across the eastern African Rift Valley during the Ice Ages.</span>
<span class="attribution"><span class="source">Elizabeth Sawchuk</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Additionally, our research showed that almost all ancient eastern Africans shared an unexpectedly high number of genetic variations with hunter-gatherers who today live in central African rainforests, making ancient eastern Africa truly a genetic melting pot. We could tell that this mixing and moving happened after about 50,000 years ago, when there was a major split in central African forager populations.</p>
<p>We also noted that the individuals in our study were genetically most like only their closest geographic neighbors. This tells us that after around 20,000 years ago, the foragers in some African regions were almost exclusively finding their partners locally. This practice must have been extremely strong and persisted for a very long time, as our results show that some groups remained genetically independent of their neighbors over several thousand years. It was especially clear in Malawi and Zambia, where the only close relationships we detected were between people buried around the same time at the same sites. </p>
<p>We don’t know why people began “living locally” again. Changing environments as the last Ice Age peaked and waned between about 26,000-11,500 years ago may have made it more economical to forage closer to home, or perhaps elaborate exchange networks reduced the need for people to travel with objects.</p>
<p>Alternatively, new group identities may have emerged, restructuring marriage rules. If so, we would expect to see artifacts and other traditions like rock art diversify, with specific types clumped into different regions. Indeed, <a href="https://www.theguardian.com/science/2022/jan/16/trail-of-african-bling-reveals-50000-year-old-social-network">this is exactly what archaeologists find</a> – a trend known as regionalization. Now we know that this phenomenon not only affected cultural traditions, but also the flow of genes. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="workers at a table sort tiny items by hand" src="https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/446872/original/file-20220216-20-cuzc12.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">Recovering and sorting archaeological remains is a slow and laborious process, where even small fragments can tell big stories.</span>
<span class="attribution"><span class="source">Chelsea Smith</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>New data, new questions</h2>
<p>As always, <a href="https://theconversation.com/ancient-dna-is-a-powerful-tool-for-studying-the-past-when-archaeologists-and-geneticists-work-together-111127">aDNA research raises as many questions as answers</a>. Finding central African ancestry throughout eastern and southern Africa prompts anthropologists to reconsider how interconnected these regions were in the distant past. This is important because central Africa has remained archaeologically understudied, in part because of political, economic and logistical challenges that make research there difficult. </p>
<p>Additionally, while genetic evidence supports a major demographic transition in Africa after 50,000 years ago, we still don’t know the key drivers. Determining what triggered the Later Stone Age transition will require closer examination of regional environmental, archaeological and genetic records to understand how this process unfolded across sub-Saharan Africa.</p>
<p>Finally, this study is a stark reminder that researchers still have <a href="https://theconversation.com/lesson-from-brazil-museums-are-not-forever-102692">much to learn from ancient individuals and artifacts</a> held in African museums, and highlights the <a href="https://theconversation.com/what-its-like-curating-ancient-fossils-a-palaeontologist-shares-her-story-96555">critical role of the curators</a> who steward these collections. While some human remains in this study were recovered within the past decade, others have been in museums for a half-century.</p>
<p>Even though technological advances are pushing back the time limits for aDNA, it is important to remember that scientists have only just begun to understand human diversity in Africa, past and present.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/GUau26szdzA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure><img src="https://counter.theconversation.com/content/175436/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Elizabeth Sawchuk receives funding from the Social Sciences and Humanities Research Council of Canada. </span></em></p><p class="fine-print"><em><span>Jessica Thompson has received funding from the Leakey Foundation, National Geographic Society, Wenner-Gren Foundation, Australian Research Council, National Science Foundation, and Hyde Family Foundation. </span></em></p><p class="fine-print"><em><span>Mary Prendergast does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A new study doubles the age of ancient DNA in sub-Saharan Africa, revealing how people moved, mingled and had children together over the last 50,000 years.Elizabeth Sawchuk, Banting Postdoctoral Fellow and Adjunct Professor of Anthropology, University of AlbertaJessica Thompson, Assistant Professor of Anthropology, Yale UniversityMary Prendergast, Associate Professor of Anthropology, Rice UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1670502021-09-01T20:10:52Z2021-09-01T20:10:52ZResearch reveals humans ventured out of Africa repeatedly as early as 400,000 years ago, to visit the rolling grasslands of Arabia<figure><img src="https://images.theconversation.com/files/418801/original/file-20210901-13-u6hxli.jpg?ixlib=rb-1.1.0&rect=22%2C16%2C1352%2C740&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Eleanor Scerri</span>, <span class="license">Author provided</span></span></figcaption></figure><p>If you stood in the middle of the Nefud Desert in central Arabia today, you’d be confronted on all sides by enormous sand dunes, some rising more than 100 meters from the desert floor. </p>
<p>The few scraggly bushes make poor browse for the herds of goats and camels that eke out a living in this harsh environment. But this wasn’t always the case.</p>
<p>Our research published today in <a href="https://www.nature.com/articles/s41586-021-03863-y">Nature</a> shows that in repeated pulses over the past 400,000 years, the Nefud Desert landscape received monsoon rains that resulted in rolling grasslands, flowing rivers and large lakes home to thousands of wild donkeys, antelopes and hippos.</p>
<p>Humans also inhabited these green corridors as they made their way out of Africa, only to disappear when conditions deteriorated again. </p>
<p>Among other findings, we present the oldest dated evidence for hominins in Arabia, in the form of stone tools dated to about 400,000 years ago. The Homininae subfamily is the group of humans of which <em>Homo sapiens</em> is the sole survivor. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=292&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=292&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=292&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=367&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=367&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418793/original/file-20210901-15-1rcoh1e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=367&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 400,000 year ‘handaxe’ stone tool from Khall Amayshan 4.</span>
<span class="attribution"><span class="source">Palaeodeserts Project (photo by Ian Cartwright)</span></span>
</figcaption>
</figure>
<h2>Early movements out of Africa</h2>
<p>Today Arabia is one of the world’s driest places, and was long thought to have played little role in human prehistory. </p>
<p>While the rich and long-studied Levant and the Mediterranean regions were considered critical for the dispersal of people out of Africa, it was thought most humans would have avoided places like the Arabian “Empty Quarter” — due to the harshness of its environmental conditions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418773/original/file-20210831-19-1s6hphj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Nefud Desert today.</span>
<span class="attribution"><span class="source">Julien Louys</span></span>
</figcaption>
</figure>
<p>But detailed scientific investigations over the past few decades have been slowly changing these ideas. A rich stone tool culture has now been recovered from the surfaces of many ancient and dried out lakebeds in Southwest Asia. </p>
<p>However, because these were from isolated beds — often hundreds of kilometres apart — and restricted to surface scatters, it was difficult to determine who had left these tools, when, and where they came from.</p>
<p>In collaboration with the Heritage Commission of the Saudi Ministry of Culture and other Saudi colleagues, our international team of researchers has been working in Saudi Arabia, Southwest Asia’s largest country, for the past decade. </p>
<p>We have recorded and studied a wealth of stone tools and animal fossils emerging from the sands and ancient lakebeds. And we’ve made some startling discoveries. </p>
<p>We recovered a <em>Homo sapiens</em> finger bone, among other fossils, from an ancient Saudi Arabian lakebed known as <a href="https://www.nature.com/articles/s41559-018-0518-2">Al Wusta</a>. These remains were dated to 85,000 years ago. This finding shows modern humans had made it out <a href="https://theconversation.com/our-fossil-finger-discovery-points-to-earlier-human-migration-in-arabia-94670">of Africa at least 20,000 years before</a> the genetic evidence indicates we left. </p>
<p>It has been thought (and many still believe) <em>Homo sapiens</em> only left Africa about 50-65,000 years ago. Our finger bone finding challenges this view, as do other discoveries - including from Madjedbebe in Australia. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/buried-tools-and-pigments-tell-a-new-history-of-humans-in-australia-for-65-000-years-81021">Buried tools and pigments tell a new history of humans in Australia for 65,000 years</a>
</strong>
</em>
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<hr>
<p>What happened to the group of people from Al Wusta remains unknown. They may have moved further into Asia, or retreated back to Africa. Or they may have become locally extinct.</p>
<h2>A green Arabia</h2>
<p>We also report a series of archaeological sites associated with multiple lakes across two locations which tell the story of human prehistory going back 400,000 years. The first of these locations, Khall Amayshan 4, is a depression located between large sand dunes covering 60,000 square metres. </p>
<p>In this single depression we found individual lakebeds dated back to 55,000, 100,000, 200,000, 300,000 and 400,000 thousand years ago. And each of the five lake phases is represented by its own unique archaeological signature.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418774/original/file-20210831-29-9oaf0z.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Aerial view of Khall Amayshan 4 showing the series of ancient lakebeds. See the two small, white 4WDs on the left for scale.</span>
<span class="attribution"><span class="source">Julien Louys</span></span>
</figcaption>
</figure>
<p>Today different populations around the world can be identified by their cultures, which include the tools they use, how they’re made and how they use them. Think chopsticks across Asia and forks in Europe, for example. </p>
<p>These tools are passed on to successive generations, even if those generations move from their point of origin. The way people made and used stone tools in the past also reflected patterns of cultural inheritance. </p>
<p>So by studying and comparing the stone tools from Arabia with those from surrounding regions, we can find out not just when people were living and moving through the region, but also where their ancestors had moved from and how they changed as they moved.</p>
<p>The most striking thing we found was that each assemblage of stone tools recovered from each ancient lakebed was very different from the others. </p>
<p>Our detailed examination of the lakebeds and the mammal fossils they preserved, including from hippos, clearly pointed to how much wetter, greener and more productive each of those phases were compared to the region today. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418796/original/file-20210901-13-2w4jz1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Antelope teeth eroding from an ancient lakebed in the Nefud Desert.</span>
<span class="attribution"><span class="source">Julien Louys</span></span>
</figcaption>
</figure>
<p>The different technologies associated with each green phase indicate there was no long-term continuity in the populations in the area. Instead, different populations, perhaps even different species of hominin, were moving in and out with each phase. </p>
<p>At the Jubbah Oasis around 150 km east of Khall Amayshan 4, two further sites – Jebel Qattar 1 and Jebel Umm Sanman 1 – filled in the last of the gaps in the timeline. These sites presented different stone tools dating to around 200,000 and 75,000 years ago, also associated with green phases. </p>
<p>Each of these phases occurs during wetter climatic periods, which are wetter due to the northern movements of the monsoon, bringing increased rainfall to the desert. Once the climate shifted back, however, conditions became arid again and humans and other fauna disappeared from Arabia. </p>
<hr>
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<strong>
Read more:
<a href="https://theconversation.com/prehistoric-desert-footprints-are-earliest-evidence-for-homo-sapiens-on-arabian-peninsula-146445">Prehistoric desert footprints are earliest evidence for Homo sapiens on Arabian Peninsula</a>
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<hr>
<p>Our findings reveal the intimate association between early human migrations and patterns of climate change — wherein different groups of humans repeatedly made it out of Africa when conditions became favourable. </p>
<p>And this happened long before the dispersal event of 50-65,000 years ago, which finally saw their descendents permanently colonise other regions.</p>
<p>Yet dozens of questions remain. Were some of these migrations from northern Neanderthals? What became of these different populations? Where did they go? Could some have made it to Southeast Asia and hence to Australia? </p>
<p>The human story won’t be told completely until we explore more long-neglected areas, much like our ancestors once did.</p><img src="https://counter.theconversation.com/content/167050/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Louys receives funding from The Australian Research Council and the Leakey Foundation</span></em></p><p class="fine-print"><em><span>Gilbert Price receives funding from The Australian Research Council and the Leakey Foundation.</span></em></p><p class="fine-print"><em><span>Huw Groucutt receives funding from the Max Planck Society.</span></em></p><p class="fine-print"><em><span>Michael Petraglia receives funding from the European Research Council and the Max Planck Society. </span></em></p>The new work presents the oldest dated evidence for hominins in Arabia, in the form of an ancient handaxe tool uncovered from the Nefud Desert.Julien Louys, Deputy Director, Australian Research Centre for Human Evolution, Griffith UniversityGilbert Price, Lecturer in Palaeontology, The University of QueenslandHuw Groucutt, Group leader of Max Planck 'Extreme Events' group., Max Planck Institute of GeoanthropologyMichael Petraglia, Professor of Archaeology, Max Planck Institute of GeoanthropologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1665652021-08-25T20:05:24Z2021-08-25T20:05:24ZWho were the Toaleans? Ancient woman’s DNA provides first evidence for the origin of a mysterious lost culture<figure><img src="https://images.theconversation.com/files/417306/original/file-20210823-19-1bucpl0.jpg?ixlib=rb-1.1.0&rect=45%2C45%2C7596%2C5030&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Stone arrowheads (Maros points) and other flaked stone implements from the Toalean culture of South Sulawesi.</span> <span class="attribution"><span class="source">Shahna Britton/Andrew Thomson</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In 2015, <a href="https://arkeologi.unhas.ac.id/archeology-department/?lang=en">archaeologists</a> from the University of Hasanuddin in Makassar, on the Indonesian island of Sulawesi, uncovered the skeleton of a woman buried in a limestone cave. Studies revealed the person from Leang Panninge, or “Bat Cave”, was 17 or 18 years old when she died some 7,200 years ago.</p>
<p>Her discoverers dubbed her Bessé’ (pronounced <em>bur-sek</em>¹) — a nickname bestowed on newborn princesses among the <a href="https://www.britannica.com/topic/Bugis">Bugis</a> people who now live in southern Sulawesi. The name denotes the great esteem local archaeologists have for this ancient woman. </p>
<p>She represents the only known skeleton of one of the Toalean people. These enigmatic hunter-gatherers inhabited the island before Neolithic farmers from mainland Asia (“<a href="https://en.wikipedia.org/wiki/Austronesian_peoples">Austronesians</a>”) spread into Indonesia around 3,500 years ago. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417311/original/file-20210823-27-1xmauxb.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">Burial of a Toalean hunter-gatherer woman dated to 7,200 years ago. Bessé’ was 17-18 years old at time of death. She was buried in a flexed position and several large cobbles were placed on and around her body. Although the skeleton is fragmented, ancient DNA was found preserved in the dense inner ear bone (petrous).</span>
<span class="attribution"><span class="source">University of Hasanuddin</span></span>
</figcaption>
</figure>
<p>Our team <a href="https://protect-au.mimecast.com/s/phV2C6X1LmSr6rk8Yfp2hJb?domain=nature.com">found</a> ancient DNA that survived inside the inner ear bone of Bessé’, furnishing us with the first direct genetic evidence of the Toaleans. This is also the first time ancient human DNA has been reported from Wallacea, the vast group of islands between Borneo and New Guinea, of which Sulawesi is the largest. </p>
<p>Genomic analysis shows Bessé’ belonged to a population with a previously unknown ancestral composition. She shares about half of her genetic makeup with present-day Indigenous Australians and people in New Guinea and the Western Pacific. This includes DNA inherited from the now-extinct <a href="https://www.nationalgeographic.com/science/article/enigmatic-human-relative-outlived-neanderthals">Denisovans</a>, who were distant cousins of Neanderthals. </p>
<p>In fact, relative to other ancient and present-day groups in the region, the proportion of Denisovan DNA in Bessé’ could indicate the main meeting point between our species and Denisovans was in Sulawesi itself (or perhaps a nearby Wallacean island).</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/evolutionary-study-suggests-prehistoric-human-fossils-hiding-in-plain-sight-in-southeast-asia-157587">Evolutionary study suggests prehistoric human fossils 'hiding in plain sight' in Southeast Asia</a>
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<p>The ancestry of this pre-Neolithic woman provides fascinating insight into the little-known population history and genetic diversity of early modern humans in the Wallacean islands — the gateway to the continent of Australia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417309/original/file-20210823-19-1oadhuw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Sulawesi is the largest island in Wallacea, the zone of oceanic islands between the continental regions of Asia and Australia. White shaded areas represent landmasses exposed during periods of lower sea level in the Late Pleistocene. The Wallace Line is a major biogeographical boundary that marks the eastern extent of the distinctive plant and animal worlds of Asia. The Toalean cave site Leang Panninge (where Bessé’ was found) is located in Sulawesi’s southwestern peninsula (see inset panel). Toalean archaeological sites have only been found in a roughly 10,000 km² area of this peninsula, south of Lake Tempe.</span>
<span class="attribution"><span class="source">Kim Newman</span></span>
</figcaption>
</figure>
<h2>Toalean culture</h2>
<p>The archaeological story of the Toaleans began more than a century ago. In 1902, the Swiss naturalists Paul and Fritz Sarasin excavated several caves in the highlands of southern Sulawesi. </p>
<p>Their digs unearthed small, finely crafted stone arrowheads known as <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0251138">Maros points</a>. They also found other distinctive stone implements and tools fashioned from bone, which they attributed to the original inhabitants of Sulawesi — the prehistoric “Toalien” people (now spelled Toalean). </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=737&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=737&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=737&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=926&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=926&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417310/original/file-20210823-15-1wn4h00.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=926&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 Toalean stone arrowhead, known as a Maros point. Classic Maros points are small (roughly 2.5cm in maxiumum dimension) and were fashioned with rows of fine tooth-like serrations along the sides and tip, and wing-like projections at the base. Although this particular stone technology seems to have been unique to the Toalean culture, similar projectile points were produced in northern Australia, Java and Japan.</span>
<span class="attribution"><span class="source">Shahna Britton/Andrew Thomson.</span></span>
</figcaption>
</figure>
<p>Some Toalean cave sites have since been excavated to a higher scientific standard, yet our understanding of this culture is at an early stage. The oldest known Maros points and other Toalean artefacts date to about 8,000 years ago. </p>
<p>Excavated findings from caves suggest the Toaleans were hunter-gatherers who preyed heavily on wild endemic <a href="https://sites.google.com/site/wildpigspecialistgroup/home/Sus-celebensis">warty pigs</a> and harvested edible shellfish from creeks and estuaries. So far, evidence for the group has only been found in one part of southern Sulawesi.</p>
<p>Toalean artefacts disappear from the archaeological record by the fifth century AD — a few thousand years after the first Neolithic settlements emerged on the island. </p>
<p>Prehistorians have long sought to determine who the Toaleans were, but efforts have been impeded by a lack of securely-dated human remains. This all changed with the discovery of Bessé’ and the ancient DNA in her bones.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417312/original/file-20210823-19-1thz0l0.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">Toalean stone arrowheads (Maros points), backed microliths (small stone implements that may have been hafted as barbs) and bone projectile points. These artefacts are from Indonesian collections curated in Makassar and mostly comprise undated specimens collected from the ground surface at archaeological sites.</span>
<span class="attribution"><span class="source">Basran Burhan</span></span>
</figcaption>
</figure>
<h2>The ancestral story of Bessé’</h2>
<p>Our results mean we can now confirm existing presumptions the Toaleans were related to the first modern humans to enter Wallacea some <a href="https://theconversation.com/buried-tools-and-pigments-tell-a-new-history-of-humans-in-australia-for-65-000-years-81021">65,000 years ago</a> or more. These seafaring hunter-gatherers were the ancestors of Aboriginal Australians and Papuans. </p>
<p>They were also the earliest inhabitants of Sahul, the supercontinent that emerged during the Pleistocene (ice age) when global sea levels fell, exposing a land bridge between Australia and New Guinea. To reach Sahul, these pioneering humans made ocean crossings through Wallacea, but little about their journeys is known. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/island-hopping-study-shows-the-most-likely-route-the-first-people-took-to-australia-93120">Island-hopping study shows the most likely route the first people took to Australia</a>
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<p>It is conceivable the ancestors of Bessé’ were among the first people to reach Wallacea. Instead of island-hopping to Sahul, however, they remained in Sulawesi.</p>
<p>But our analyses also revealed a deep ancestral signature from an early modern human population that originated somewhere in continental Asia. These ancestors of Bessé’ did not intermix with the forebears of Aboriginal Australians and Papuans, suggesting they may have entered the region after the initial peopling of Sahul — but long before the Austronesian expansion. </p>
<p>Who were these people? When did they arrive in the region and how widespread were they? It’s unlikely we will have answers to these questions until we have more ancient human DNA samples and pre-Neolithic fossils from Wallacea. This unexpected finding shows us how little we know about the early human story in our region.</p>
<h2>A new look at the Toaleans</h2>
<p>With funds awarded by the Australian Research Council’s Discovery <a href="https://www.arc.gov.au/grants/discovery-program/discovery-projects">program</a> we are initiating a new project that will explore the Toalean world in greater detail. Through archaeological excavations at Leang Panninge we hope to learn more about the development of this unique hunter-gatherer culture. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417313/original/file-20210823-21-1y8qu2m.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">Excavations at Leang Panninge cave, Mallawa, South Sulawesi.</span>
<span class="attribution"><span class="source">Leang Panninge Research Team.</span></span>
</figcaption>
</figure>
<p>We also wish to address longstanding questions about Toalean social organisation and ways of life. For example, some scholars have inferred the Toaleans became so populous that these hitherto small and scattered groups of foragers began to settle down in large sedentary communities, and possibly even domesticated wild pigs.</p>
<p>It has also recently been <a href="https://www.sciencedirect.com/science/article/abs/pii/S2352409X16300694">speculated</a> Toaleans were the mysterious Asian seafarers who visited Australia in ancient times, introducing the dingo (or more accurately, the domesticated ancestor of this now-wild canid). There is clearly much left to uncover about the long island story of Bessé’ and her kin. </p>
<hr>
<p>¹<em>The “bur” syllable is pronounced as in the English word “bursary”. The “k” is essentially a strangulated stop in the throat, akin to the “t” in the Cockney “bo'ol”, for bottle. (With thanks to Professor Campbell Macknight).</em></p><img src="https://counter.theconversation.com/content/166565/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adam Brumm receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Adhi Agus Oktaviana is a PhD candidate in Place, Evolution and Rock Art Heritage Unit, Griffith University, Australia. </span></em></p><p class="fine-print"><em><span>Akin Duli receives funding from Universitas Hasanuddin and Universiti Sains Malaysia. He is affiliated with Archaeology Department, Universitas Hasanuddin. </span></em></p><p class="fine-print"><em><span>Basran Burhan is a PhD student at Griffith University</span></em></p><p class="fine-print"><em><span>Selina Carlhoff receives funding from the European Research Council and the Max Planck Society. </span></em></p><p class="fine-print"><em><span>Cosimo Posth 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 first ancient human DNA from the Indonesian island of Sulawesi — and the wider Wallacea islands group — sheds light on the early human history of the region.Adam Brumm, Professor, Griffith UniversityAdhi Oktaviana, PhD Candidate, Griffith UniversityAkin Duli, Professor, Universitas HasanuddinBasran Burhan, PhD candidate, Griffith UniversityCosimo Posth, Junior Professor, University of TübingenSelina Carlhoff, Max Planck Institute of GeoanthropologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1630842021-06-24T20:13:53Z2021-06-24T20:13:53Z‘Homo’ who? A new mystery human species has been discovered in Israel<figure><img src="https://images.theconversation.com/files/407818/original/file-20210623-15-156gf8w.jpeg?ixlib=rb-1.1.0&rect=10%2C20%2C3488%2C2308&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Yossi Zaidner</span></span></figcaption></figure><p>An international group of archaeologists have discovered a missing piece in the story of human evolution.</p>
<p>Excavations at the Israeli site of Nesher Ramla have recovered a skull that may represent a late-surviving example of a distinct <em>Homo</em> population, which lived in and around modern-day Israel from about 420,000 to 120,000 years ago. </p>
<p>As researchers Israel Hershkovitz, Yossi Zaidner and colleagues detail in two companion studies <a href="https://science.sciencemag.org/cgi/doi/10.1126/science.abh3169">published</a> <a href="https://science.sciencemag.org/cgi/doi/10.1126/science.abj3077">today</a> in Science, this archaic human community traded both their culture and genes with nearby <em>Homo sapiens</em> groups for many thousands of years.</p>
<h2>The new fossils</h2>
<p>Pieces of a skull, including a right parietal (towards the back/side of the skull) and an almost complete mandible (jaw) were dated to 140,000–120,000 years old, with analysis finding the person it belonged to wasn’t fully <em>H. sapiens</em>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=313&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=313&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=313&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=394&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=394&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407817/original/file-20210623-27-pq5orw.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=394&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 Nesher Ramla mandible and skull.</span>
<span class="attribution"><span class="source">Avi Levin and Ilan Theiler, Sackler / Tel Aviv University</span></span>
</figcaption>
</figure>
<p>Nor were they Neanderthal, however, which was the only other type of human thought to have been living in the region at the time.</p>
<p>Instead, this individual falls right smack in the middle: a unique population of <em>Homo</em> never before recognised by science.</p>
<p>Through detailed comparison with many other fossil human skulls, the researchers found the parietal bone featured “archaic” traits that are substantially different from both early and recent <em>H. sapiens</em>. In addition, the bone is considerably thicker than those found in both Neanderthals and most early <em>H. sapiens</em>.</p>
<p>The jaw too displays archaic features, but also includes forms commonly seen in Neanderthals.</p>
<p>The bones together reveal a unique combination of archaic and Neanderthal features, distinct from both early <em>H. sapiens</em> and later Neanderthals.</p>
<h2>Are there are more of these people?</h2>
<p>The authors suggest fossils found at other Israeli sites, including the famous <a href="https://humanorigins.si.edu/evidence/human-fossils/fossils/tabun-1">Lady of Tabun</a>, might also be part of this new human population, in contrast to their previous Neanderthal or <em>H. sapiens</em> identification. </p>
<p>The “Lady of Tabun” (known to archaeologists as Tabun C1) was discovered in 1932 by pioneering archaeologist <a href="https://trowelblazers.com/yusra-expert-excavator-of-mount-carmel/">Yusra</a> and her field director, Dorothy Garrod.</p>
<p>Extensively studied, this important specimen taught us much about Neanderthal anatomy and behaviour in a time when very little was known about our enigmatic evolutionary cousins. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ancient-teenager-the-first-known-person-with-parents-of-two-different-species-101965">Ancient teenager the first known person with parents of two different species</a>
</strong>
</em>
</p>
<hr>
<p>If Tabun C1 and others from the Qesem and Zuttiyeh Caves were indeed members of the Nasher Ramel <em>Homo</em> group, this reanalysis would explain some inconsistencies in their anatomy previously noted by researchers.</p>
<p>The mysterious Nesher Ramla <em>Homo</em> may even represent our most recent common ancestor with Neanderthals. Its mix of traits supports genetic evidence that early <a href="https://www.nature.com/articles/ncomms16046">gene flow between <em>H. sapiens</em> and Neanderthals</a> occurred between 400,000 and 200,000 years ago. In other words, that interbreeding between the different <em>Homo</em> populations was more common than previously thought.</p>
<p>Even more puzzling, the team also found a collection of some 6,000 stone tools at the Nesher Ramla site. </p>
<p>These tools were made the same way contemporaneous <em>H. sapiens</em> groups made their technology, with the similarity so strong it appears the two populations — Nesher Ramla <em>Homo</em> and <em>H. sapiens</em> — were hanging out on a regular basis. It seems they weren’t just exchanging genes, but also tips on tool-making. </p>
<h2>And there was fire!</h2>
<p>The site also produced bones of animals caught, butchered, and eaten on-site. These findings indicate Nesher Ramla <em>Homo</em> hunted a range of species, including tortoise, gazelle, aurochs, boar and ostrich. </p>
<p>Furthermore, they were using <a href="https://www.youtube.com/watch?v=Wpfwu__PF7Y&t=9s">fire to cook their meals</a>, evident through the uncovering of a campfire feature the same age as the fossils. Indeed, the Nesher Ramla <em>Homo</em> were not only collecting wood to make campfires and cook, but were also actively managing their fires as people do today. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407814/original/file-20210623-27-1aabcll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Exposure of animal bones and lithic artifacts in the layer with the Nesher Ramla Homo fossils.</span>
<span class="attribution"><span class="source">Yossi Zaidner</span></span>
</figcaption>
</figure>
<p>While the earliest indications of controlled use of fire is much older — perhaps one million years ago - the interesting thing about this particular campfire is the evidence that Nesher Ramla people tended to it as carefully as contemporary <em>H. sapiens</em> and Neanderthals did their own fires.</p>
<p>Most impressive is that the campfire feature survived, intact, outside of a protected cave environment for so long. It is now the oldest intact campfire ever found in the open air.</p>
<p>In sum, if we think of the story of human evolution like an Ikea bookcase that isn’t quite coming together, this discovery is effectively like finding the missing shelf buried at the bottom of the box. The new Nesher Ramla <em>Homo</em> allows for a better-fitting structure, although a few mysterious “extra” pieces remain to be pondered over. </p>
<p>For example, exactly how did the different <em>Homo</em> groups interact with each other? And what does it mean for the cultural and biological changes that were occurring for <em>Homo</em> populations in this period? </p>
<p>Continuing to work with these questions (the “extra pieces”) will help us build a better understanding of our human past.</p>
<img src="https://counter.theconversation.com/content/163084/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr Michelle Langley is a Senior Research Fellow in the Australian Research Centre for Human Evolution and Lecturer in Archaeology in the School of Environment and Science at Griffith University. She receives funding from the Australian Research Council. </span></em></p>The 140,000-year-old skull fossils are leading to more questions than answers. Also found was the oldest intact campfire ever found in the open air.Michelle Langley, Senior Research Fellow, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1615852021-06-23T20:04:12Z2021-06-23T20:04:12ZDirty secrets: sediment DNA reveals a 300,000-year timeline of ancient and modern humans living in Siberia<figure><img src="https://images.theconversation.com/files/407374/original/file-20210621-35447-1spt3ea.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Collection of sediment DNA samples in the Main Chamber of Denisova Cave.</span> <span class="attribution"><span class="source">Bert Roberts</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In the foothills of the Altai Mountains in southern Siberia lies Denisova Cave. It is the only site in the world known to have been inhabited by the eponymous Denisovans and their close relatives the Neanderthals (<em>Homo neanderthalensis</em>) — which <a href="https://www.nature.com/articles/d41586-018-06004-0">overlapped at times</a> — as well as by some of the earliest modern humans (<em>Homo sapiens</em>) to have dispersed into northern Asia.</p>
<p>Our <a href="https://www.nature.com/articles/s41586-021-03675-0">new study</a> pieces together the history of this site over the past 300,000 years from fragments of ancient DNA that survived in the cave sediments. Our findings reveal multiple turnovers of archaic and modern humans during this period, as well as major changes in the diversity of other animals.</p>
<p>We discovered Denisovans were the earliest toolmakers at the site, while Neanderthals were the sole human occupants between about 130,000 and 80,000 years ago. The first modern humans arrived much later, just as the last Denisovans and Neanderthals were leaving the scene.</p>
<p>We also detected marked changes in the types of human and animal DNA around 200,000 and 100,000 years ago, coincident with major shifts in climate and environmental conditions.</p>
<h2>Genetic ghosts</h2>
<p>Excavations in the cave by our Russian colleagues have unearthed about a dozen fossils of Denisovans and Neanderthals over the past 40 years, but none of modern humans. </p>
<p>Rather, the presence of modern humans at the cave has been surmised based on the recovery of artefacts made from stone, animal bones and teeth, mammoth ivory, ostrich eggshells, marble and gemstones.</p>
<p>The rarity of fossils at the site has also meant that questions persist about when different groups of humans occupied the cave, and which of them was responsible for making specific artefacts.</p>
<p>We managed to put flesh on the missing bones by using genetic traces of ancient humans and various other mammals preserved in the cave sediments. And we did so without having to find more fossils.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403446/original/file-20210530-23-xbvsni.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Project leader, Matthias Meyer, in the ancient DNA clean lab at the Max Planck Institute for Evolutionary Anthropology.</span>
<span class="attribution"><span class="source">Max Planck Institute for Evolutionary Anthropology</span></span>
</figcaption>
</figure>
<p>Our latest work is the most comprehensive study yet of ancient DNA extracted from sediment at any single site in the world. It builds on our <a href="https://science.sciencemag.org/content/356/6338/605">trailblazing research</a> published in 2017.</p>
<p>We extracted mitochondrial DNA from more than 700 samples and anchored them to a <a href="https://www.nature.com/articles/s41586-018-0843-2">timeline</a> for Denisova Cave, generating a detailed picture of which humans and animals were present at this famous site at various times in the past.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fresh-clues-to-the-life-and-times-of-the-denisovans-a-little-known-ancient-group-of-humans-110504">Fresh clues to the life and times of the Denisovans, a little-known ancient group of humans</a>
</strong>
</em>
</p>
<hr>
<h2>Turbulent times</h2>
<p>We retrieved ancient human DNA from 175 sediment samples — more than ten times the number of human fossils found at the site. Several interesting findings emerged from our genetic analyses.</p>
<p>We found Denisovans were present at the cave, on and off, from 250,000 years ago until 60,000 years ago. And they were the only humans at the site between 250,000 and 200,000 years ago, so we can now say with more confidence they likely produced the stone tools recovered from these layers. </p>
<p>Denisovan fossils and ancient DNA have been found at only one <a href="https://theconversation.com/how-midnight-digs-at-a-holy-tibetan-cave-opened-a-window-to-prehistoric-humans-living-on-the-roof-of-the-world-148927">other site</a>, on the edge of the Tibetan Plateau.</p>
<p>Meanwhile, Neanderthals first appeared at Denisova Cave about 200,000 years ago, with a variety of DNA that was previously unknown. They vanished from the site about 40,000 years ago, around the same time Neanderthals disappeared in other parts of Eurasia.</p>
<p>Importantly, we could only find traces of Neanderthal DNA in sediments dated to between 130,000 and 80,000 years ago at Denisova Cave — and none of Denisovans.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=699&fit=crop&dpr=1 600w, https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=699&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=699&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=878&fit=crop&dpr=1 754w, https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=878&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/404606/original/file-20210605-27-1ye28kn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=878&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Summary timeline of the different types of human, bear and hyaena DNA in sediments at Denisova Cave. White gaps indicate missing parts of the sedimentary sequence. The graph on the left shows the changes in climate between relatively cold and warm conditions recorded in drill cores from Lake Baikal, also in southern Siberia.</span>
<span class="attribution"><span class="source">Bert Roberts</span></span>
</figcaption>
</figure>
<p>This time interval coincides with a major change in Earth’s climate: the start of the last interglacial. This was a relatively warm period similar to the present. It marked a switch from one type of Denisovan DNA before 130,000 years ago to another after 80,000 years ago.</p>
<p>This matches previous findings from genetic analysis of Denisovan fossils, which indicated a possible turnover in Denisovan populations. It also coincides with a population replacement of <a href="https://science.sciencemag.org/content/372/6542/eabf1667.full">Neanderthals in Spain</a> about 100,000 years ago — again identified from ancient DNA in cave sediments.</p>
<p>We also recovered the ancient DNA of modern humans from sediments deposited at Denisova Cave within the last 60,000 years. No modern human fossils have been found at the site, so these traces of DNA — from the same layers as the jewellery and pendants made from stone, bone, tooth and ivory — are the first direct evidence of <em>Homo sapiens</em>’ presence at the cave.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=346&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=346&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=346&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=435&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=435&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403456/original/file-20210530-15-1thvbk4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=435&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Selection of stone tools and personal ornaments made from bone, tooth and ivory recovered from the same sediment layers as modern human ancient DNA.</span>
<span class="attribution"><span class="source">Institute of Archaeology and Ethnography of the Siberian Branch of the Russian Academy of Sciences.</span></span>
</figcaption>
</figure>
<h2>Denisova zoo</h2>
<p>We recovered other ancient animal DNA from 94% of the sediment samples. This is providing new vistas into cave use by more than 12 taxonomic families of mammals, including species such as bear, hyena, wolf and woolly mammoth.</p>
<p><a href="https://www.nature.com/articles/s41598-019-49930-3">Previous studies</a> have shown the cave was occupied at times by hyenas and bears. Our findings take this further, revealing cave bears dominated between 300,000 and 200,000 years ago, after which brown bears became more abundant.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dishing-the-dirt-sediments-reveal-a-famous-early-human-cave-site-was-also-home-to-hyenas-and-wolves-122458">Dishing the dirt: sediments reveal a famous early human cave site was also home to hyenas and wolves</a>
</strong>
</em>
</p>
<hr>
<p>We also identified two major shifts in the types of hyena present at different times, with turnovers occurring when climatic conditions changed from relatively warm to cold 200,000 years ago, and from relatively cold to warm 100,000 years ago.</p>
<p>The timing of these turnovers, coupled with the patterns we discovered for Denisovans and Neanderthals, suggests these events were likely connected to environmental changes.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/aqdu2vjuCUY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A guided tour of our key findings, presented by the lead author of the study, Elena Zavala from the Max Planck Institute for Evolutionary Anthropology.</span></figcaption>
</figure>
<h2>Sediment diaries</h2>
<p>The power of sediment DNA lies in the fact that sediments are ubiquitous at archaeological and palaeontological sites. Even tiny samples can contain genetic traces of a variety of animals — including humans — in the absence of fossils.</p>
<p>Sediments also often contain plant remains and other materials that can be used to reconstruct ancient environments, with timelines obtained by <a href="https://www.nature.com/articles/520438a">directly dating</a> sediment grains.</p>
<p>By sampling sites with high densities of sediment DNA, the ebb and flow of humans and other animals can be compared to records of past environmental change. Making these crucial connections can help illuminate the dark corners of our planet’s history.</p><img src="https://counter.theconversation.com/content/161585/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Elena Zavala receives funding from the Max Planck Society. </span></em></p><p class="fine-print"><em><span>Matthias Meyer receives funding from the Max Planck Society. </span></em></p><p class="fine-print"><em><span>Richard 'Bert' Roberts receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Zenobia Jacobs receives funding from the Australian Research Council. </span></em></p>Our research has also uncovered major long-term changes in ancient animal populations at Denisova Cave, and has provided the first direct evidence of Homo sapiens having lived there.Elena Zavala, PhD Student, Max Planck Institute for Evolutionary AnthropologyMatthias Meyer, Group Leader, Advanced DNA Sequencing Techniques Group, Max Planck Institute for Evolutionary AnthropologyRichard 'Bert' Roberts, Director, ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH), University of WollongongZenobia Jacobs, Professor, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1585742021-05-05T18:06:48Z2021-05-05T18:06:48ZEarly humans used fire to permanently change the landscape tens of thousands of years ago in Stone Age Africa<figure><img src="https://images.theconversation.com/files/398430/original/file-20210503-13-nd6j8k.JPG?ixlib=rb-1.1.0&rect=0%2C179%2C4608%2C3269&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Today the shoreline of Lake Malawi is open, not forested the way it was before ancient humans started modifying the landscape.</span> <span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Fields of rust-colored soil, spindly cassava, small farms and villages dot the landscape. Dust and smoke blur the mountains visible beyond massive Lake Malawi. Here in tropical Africa, you can’t escape the signs of human presence.</p>
<p>How far back in time would you need to go in this place to discover an entirely natural environment?</p>
<p>Our work has shown that it would be a very long time indeed – <a href="https://advances.sciencemag.org/content/7/19/eabf9776">at least 85,000 years</a>, eight times earlier than the <a href="https://doi.org/10.1126/science.aax1192">world’s first land transformations via agriculture</a>.</p>
<p><a href="https://scholar.google.com/citations?user=MQkcYDYAAAAJ&hl=en&oi=ao">We</a> <a href="https://scholar.google.com/citations?user=kNBySP0AAAAJ&hl=en&oi=ao">are</a> <a href="https://scholar.google.com/citations?user=ZGB_9bQAAAAJ&hl=en&oi=ao">part</a> of an interdisciplinary collaboration between archaeologists who study past human behavior, geochronologists who study the timing of landscape change and paleoenvironmental scientists who study ancient environments. By combining evidence from these research specialities, we have identified an instance in the very distant past of early humans bending environments to suit their needs. In doing so, they transformed the landscape around them in ways still visible today.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="people excavate stone tools below the ground's surface" src="https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395547/original/file-20210417-17-gv4vry.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">Crew members excavate artifacts at a site in Karonga, Malawi, where stone tools are buried more than 3 feet (1 meter) below the modern ground surface.</span>
<span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Digging for behavioral and environmental clues</h2>
<p>The dry season is the best time to do archaeological fieldwork here, and finding sites is easy. Most places we dig in these red soils, we find stone artifacts. They are evidence that someone sat and skillfully broke stones to create edges so sharp they can still draw blood. Many of these stone tools can be fit back together, reconstructing a single action by a single person, from tens of thousands of years ago.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="stone tools paired together" src="https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=414&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=414&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=414&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395548/original/file-20210417-13-4zrut7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Middle Stone Age artifacts, some of which can be fit back together.</span>
<span class="attribution"><a class="source" href="https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abf4098">Sheila Nightingale</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>So far we’ve recovered more than 45,000 stone artifacts here, buried many feet (1 to 7 meters) below the surface of the ground. The sites we are excavating date to a time ranging from about 315,000 to 30,000 years ago known as the Middle Stone Age. This was also a period in Africa when innovations in human behavior and creativity pop up frequently – and <a href="https://doi.org/10.1038/s41586-021-03419-0">earlier than anywhere else in the world</a>. </p>
<p>How did these artifacts get buried? Why are there so many of them? And what were these ancient hunter-gatherers doing as they made them? To answer these questions, we needed to figure out more about what was happening in this place during their time.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="barge with drill floats in the distance on lake water" src="https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395549/original/file-20210417-13-90z5s9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Viphya drill barge on Lake Malawi, where researchers braved waterspouts and lake fly swarms to obtain a long record of past environments.</span>
<span class="attribution"><span class="source">Andy Cohen</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>For a clearer picture of the environments where these early humans lived, we turned to the fossil record preserved in layers of mud at the bottom of Lake Malawi. Over millennia, pollen blown into the water and tiny lake-dwelling organisms became trapped in <a href="http://lrc.geo.umn.edu/laccore/">layers of muck on the lake’s floor</a>. Members of our collaborative team extracted a <a href="https://doi.org/10.1016/j.palaeo.2010.10.030">1,250-foot (380-meter) drill core</a> of mud from a modified barge, then painstakingly tallied the microscopic fossils it contained, layer by layer. They then used them to reconstruct ancient environments across the entire basin.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Malawi landscape with patches of forest high in the hills" src="https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=423&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=423&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395893/original/file-20210420-21-1rylzf9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=423&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Today, the high plateaus of northern Malawi harbor most of the remaining forests that once extended all the way to the Lake Malawi shoreline.</span>
<span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Today, this region is characterized by bushy, <a href="https://doi.org/10.1016/j.actao.2020.103599">fire-tolerant open woodlands</a> that do not develop a thick and enclosed canopy. Forests that do develop these canopies harbor the richest diversity in vegetation; this ecosystem is now restricted to patches that occur at higher elevations. But these forests once stretched all the way to the lakeshore.</p>
<p>Based on the fossil plant evidence present at various times in the drill cores, we could see that the area around Lake Malawi repeatedly alternated between wet times of forest expansion and dry periods of forest contraction. </p>
<p>As the area underwent cycles of aridity, driven by natural climate change, the lake shrank at times to only 5% of its present volume. When lake levels eventually rose each time, forests <a href="https://doi.org/10.1111/gcb.14150">encroached on the shoreline</a>. This happened time and time again over the last 636,000 years.</p>
<h2>Harnessing fire to manage resources</h2>
<p>The mud in the core also contains a record of fire history, in the form of tiny fragments of charcoal. Those little flecks told us that around 85,000 years ago, something strange happened around Lake Malawi. Charcoal production spiked, erosion increased and, for the first time in more than half a million years, rainfall did not bring forest recovery.</p>
<p>At the same time this charcoal burst appears in the drill core record, our sites began to show up in the archaeological record – eventually becoming so numerous that they formed one continuous landscape littered with stone tools. Another drill core immediately offshore showed that as site numbers increased, more and more charcoal was washing into the lake. Early humans had begun to make their first permanent mark on the landscape.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="people silhouetted against bonfire at night" src="https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=266&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=266&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=266&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=334&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=334&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395891/original/file-20210420-23-1ucsfyb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=334&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many people around the world still rely on fire for warmth, cooking, ritual and socializing – including the research crew when doing fieldwork.</span>
<span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Fire use is a technology that stretches back <a href="https://doi.org/10.1098/rstb.2015.0164">at least a million years</a>. Using it in such a transformative way is human innovation at its most powerful. Modern hunter-gatherers use fire to warm themselves, cook food and socialize, but many also deploy it as an engineering tool. Based on the wide-scale and permanent transformation of vegetation into more fire-tolerant woodlands, we infer that this was what these ancient hunter-gatherers were doing.</p>
<p>By converting the natural seasonal rhythm of wildfire into something more controlled, people can encourage specific areas of vegetation to grow at different stages. This so-called “<a href="https://doi.org/10.1002/evan.21482">pyrodiversity</a>” establishes miniature habitat patches and diversifies opportunities for foraging, kind of like increasing product selection at a supermarket.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="people digging in red earth at an outdoor archaeological site" src="https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395552/original/file-20210417-15-5xlhfa.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 research team exposes ancient stone tools near Karonga, Malawi.</span>
<span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Just like today, changing any part of an ecosystem has consequences everywhere else. With the loss of closed forests in ancient Malawi, the vegetation became dominated by more open woodlands that are resilient to fire – but these did not contain the same species diversity. This combination of rainfall and reduced tree cover also increased opportunities for erosion, which spread sediments into a thick blanket known as an alluvial fan. It sealed away archaeological sites and created the landscape you can see here today.</p>
<h2>Human impacts can be sustainable</h2>
<p>Although the spread of farmers through Africa within the last few thousand years brought about more <a href="https://doi.org/10.1073/pnas.1802172115">landscape and vegetation transformations</a>, we have found that the legacy of human impacts was already in place tens of thousands of years before. This offers a chance to understand how such impacts can be sustained over very long timescales.</p>
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<a href="https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="aerial view of an excavation site in Malawi" src="https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395894/original/file-20210420-21-1ysfwud.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>
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<span class="caption">Open woodlands have grown over alluvial fans that formed during the Middle Stone Age. Trenches such as this one at an excavation site show multiple layers of discarded artifacts over a period of tens of thousands of years.</span>
<span class="attribution"><span class="source">Jessica Thompson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>Most people associate human impacts with a time after the Industrial Revolution, but paleo-scientists have a deeper perspective. With it, researchers like us can see that wherever and whenever humans lived, we must abandon the idea of “<a href="https://www.pnas.org/content/118/17/e2023483118">pristine nature</a>,” untouched by any human imprint. However, we can also see how humans shaped their environments in sustainable ways over very long periods, causing ecosystem transformation without collapse.</p>
<p>Seeing the long arc of human influence therefore gives us much to consider about not only our past, but also our future. By establishing long-term ecological patterns, conservation efforts related to fire control, species protection and human food security can be <a href="https://doi.org/10.1038/s41559-020-01361-4">more targeted and effective</a>. People living in the tropics, such as Malawi today, are especially vulnerable to the economic and social impacts of food insecurity brought about by <a href="https://www.un.org/press/en/2019/gaef3516.doc.htm">climate change</a>. By studying the deep past, we can establish connections between long-term human presence and the biodiversity that sustains it.</p>
<p>With this knowledge, people can be better equipped to do what humans had already innovated nearly 100,000 years ago in Africa: manage the world around us.</p>
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<figcaption><span class="caption">Paleoanthropologist Jessica Thompson explains the research.</span></figcaption>
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<p>[<em>The Conversation’s newsletter explains what’s going on with the coronavirus pandemic. <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=coronavirus-going-on">Subscribe now</a>.</em>]</p><img src="https://counter.theconversation.com/content/158574/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jessica Thompson has received funding for this research from the Australian Research Council, Wenner-Gren Foundation, and National Geographic Society-Waitt Foundation. She is affiliated with Yale University and the Yale Peabody Museum of Natural History, Arizona State University, the Paleoanthropology Society, the Society of Africanist Archaeologists, and the Society for American Archaeology. </span></em></p><p class="fine-print"><em><span>David K. Wright has received funding from the Wenner-Gren Foundation, National Geographic Foundation, Nordforsk (Nordic Council of Ministers) fund and the National Research Foundation of Korea. He is affiliated with the University of Oslo and the State Key Laboratory of Loess and Quaternary Geology at the Chinese Academy of Sciences and is a member of the Society for American Archaeology and the Society of Africanist Archaeologists.</span></em></p><p class="fine-print"><em><span>Sarah Ivory receives funding from the US National Science Foundation and the Belmont Forum. </span></em></p>Combining evidence from archaeology, geochronology and paleoenvironmental science, researchers identified how ancient humans by Lake Malawi were the first to substantially modify their environment.Jessica Thompson, Assistant Professor of Anthropology, Yale UniversityDavid K. Wright, Professor of Archaeology, Conservation and History, University of OsloSarah Ivory, Assistant Professor of Geosciences, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1567152021-04-05T12:34:50Z2021-04-05T12:34:50ZHow did humans evolve, and will we evolve more?<figure><img src="https://images.theconversation.com/files/389682/original/file-20210315-13-16jufk3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3100%2C2408&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This skull, found in France, was among the first fossils to be recognized as belonging to our own species.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/homo-sapien-skull-found-in-abri-de-cro-magnon-france-news-photo/541321135">DEA /G. Cigolini via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
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<p><strong>How did humans evolve, and will they evolve more? – Anya T., 13, Brookline, Massachusetts</strong></p>
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<p>Everything that is alive today has evolved, <a href="https://www.sciencemag.org/news/2018/06/momentous-transition-multicellular-life-may-not-have-been-so-hard-after-all">including human beings</a>. </p>
<p>Our ancestors evolved many traits that helped them survive in their environments, and we still have many of those traits today. Two of the most important and consequential traits are walking on two legs and having a large brain.</p>
<p>I’m a <a href="https://scholar.google.com/citations?user=TZ5HyRMAAAAJ&hl=en&oi=ao">scholar of human evolution</a>. I study how evolution works, including how it has changed the shape of the bones in the skull and ankle of humans and other primates.</p>
<p>So how did humans evolve, and where will evolution take us in the future?</p>
<h2>What evolution is</h2>
<p>People pass traits to their children through genes. We can have <a href="https://www.genome.gov/genetics-glossary/Allele">different versions of the same genes</a> – called alleles – and evolution occurs when the proportion of these alleles in the population <a href="https://www.nature.com/scitable/definition/evolution-78/">changes over multiple generations</a>.</p>
<p>Alleles in a population often help certain individuals survive in their own environment. This means that evolution isn’t about becoming the fastest, or the strongest, or the smartest, because it all depends on the environment.</p>
<p>Early ancestors of humans evolved to walk upright on two legs around <a href="https://humanorigins.si.edu/human-characteristics/walking-upright">6 million years ago</a>.</p>
<p>Scientists are still trying to figure out <a href="https://www.smithsonianmag.com/science-nature/becoming-human-the-evolution-of-walking-upright-13837658/">why our ancestors started walking on two legs</a>. Today, the most common hypothesis is that walking on two legs probably helped our ancestors to move between forest patches that were shrinking due to a changing climate.</p>
<p>What about our brains?</p>
<p>Relative to the size of our bodies, humans have the largest brains on the planet. Elephants have bigger brains, but their bodies are even bigger than ours.</p>
<p>Without big brains we wouldn’t be able to innovate, such as by creating an alphabet, sending machines to Mars or creating vaccines that protect us against measles and other dangerous diseases. Our big brains make it possible to share information culturally through books, storytelling or even movies, rather than only passing our genes to the next generation.</p>
<p>Our ancestors’ brains got bigger over the course of human evolution until about 200,000 to 300,000 years ago when modern humans, known as <em><a href="https://www.britannica.com/topic/Homo-sapiens/Origin">Homo sapiens</a></em>, showed up.</p>
<p>After that, human brains actually <a href="https://www.scientificamerican.com/article/why-have-our-brains-started-to-shrink/">started to get a bit smaller</a>, possibly because our bodies have gotten smaller or perhaps because a slightly smaller brain may not use as much energy.</p>
<p><a href="https://www.sciencemag.org/news/2016/05/humans-are-still-evolving-and-we-can-watch-it-happen">Humans are still evolving</a>. For example, because they have a largely vegetarian diet like their ancestors did, many people who live in the city of <a href="https://www.sciencedaily.com/releases/2016/03/160329184939.htm">Pune, India, have a mutation</a> that helps them more efficiently process omega-3 and omega-6 fatty acids. Vegetarians can have trouble getting enough of those nutrients, which are important for having a healthy brain.</p>
<h2>Humans in the future</h2>
<p>Nobody knows where human evolution will lead.</p>
<p>All organisms, including humans, adapt to their environments. And those environments can change – sometimes in entirely unpredictable ways. </p>
<p>It may disappoint you to hear that people aren’t likely to evolve superpowers like those in the <a href="https://www.imdb.com/title/tt0120903/">“X-Men” movies</a> or characters in the <a href="https://www.marvel.com/movies">Marvel Cinematic Universe</a>, at least for the most part.</p>
<p>However, there is one Marvel character humans have evolved to be like: <a href="https://www.cbr.com/iron-man-tony-stark-inventions-that-completely-changed-the-marvel-universe/">Iron Man</a>.</p>
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<figcaption><span class="caption">The inventions of Tony Stark, who turns into Iron Man, can both save the day and wreak havoc in the Marvel Universe.</span></figcaption>
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<p>Like Iron Man, humans are smart enough to invent things that can make some of us live longer or have more fun, whether it’s a device that keeps an ailing heart beating or an airplane that makes it possible to fly without wings.</p>
<p>It’s unlikely that humans will ever evolve laser beam eyes or wings out of our backs like the X-Men characters <a href="https://marvel.fandom.com/wiki/Scott_Summers_(Earth-616)">Cyclops</a> and <a href="https://marvel.fandom.com/wiki/Warren_Worthington_III_(Earth-616)">Archangel</a>. But other abilities that humans have evolved over millions of years of evolution allow us to do many of those same things, through innovation.</p>
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<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/156715/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Evan Simons receives funding from the National Science Foundation.</span></em></p>Our biggest evolutionary advantages are an ability to walk on two legs and our big brains.Evan Simons, Postdoctoral Research Associate in Anthropology, University at BuffaloLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1507552021-01-07T12:19:36Z2021-01-07T12:19:36ZFinds in Tanzania’s Olduvai Gorge reveal how ancient humans adapted to change<figure><img src="https://images.theconversation.com/files/371147/original/file-20201124-17-1292l8x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The research site at the Olduvai Gorge.</span> <span class="attribution"><span class="source">Author supplied</span></span></figcaption></figure><p>The ability to adapt to changing environments has deep roots. In a technology-driven world, people tend to conflate adaptability with technological change, especially when it comes to navigating adverse climates and places. But not every technological revolution is a result of environmental change.</p>
<p>Sometimes existing tool kits – containing, for instance, simple cutting and scraping flakes – allowed early humans to exploit new resources and thrive under changing conditions. As a species, humans are also characterised by the ability to swiftly use disrupted environments. And, as new research conducted at Tanzania’s Olduvai Gorge reveals, this adaptability was already apparent millions of years ago.</p>
<p>Our <a href="https://www.nature.com/articles/s41467-020-20176-2">new study</a>, published in Nature Communications, is the result of a true team and multidisciplinary effort. Principal investigators from Canada and Tanzania worked with partners in Africa, North America and Europe to describe a large assemblage of stone tools, fossil bones and chemical proxies from dental and plant materials. We also examined the microscopic bits of silica left behind by plants, ancient pollen, and airborne charcoal from natural fires retrieved from ancient riverbed and lake outcrops in the Serengeti plains. </p>
<p>Taken together, the data we gathered presents the earliest evidence for human activity in the Olduvai Gorge: about 2 million years ago. It also shows that early humans used a great diversity of habitats as they adjusted to constant change. </p>
<p>East Africa is among the world’s prime regions for human origins research. It boasts extraordinary records of extinct species spanning several million years. Over more than a century, palaeoanthropologists have explored the sedimentary outcrops and unearthed hominin fossils in surveys and digs. But the link between these fossils and their environmental context remains elusive. That’s because there aren’t many palaeoecological datasets directly linked to the cultural remains left by extinct early humans. Our <a href="https://www.nature.com/articles/s41467-020-20176-2">study</a> is an important step in filling that gap.</p>
<h2>Varied artefacts and data</h2>
<p>The dataset was obtained during a recent survey of the unexplored western portion of the ancient basin. The locality is called Ewass Oldupa; in the Maa language spoken by local residents, this means “the way to the Gorge”. It’s an appropriate name: the site straddles the path that links the canyon’s rim with its bottom. Here, the exposed canyon wall reveals two million years of history. </p>
<p>The team worked closely with Maasai scholars and communities when excavating the site. The research group employed a large group of participants, male and female, selected by the local community. And in addition to <a href="https://www.webtoons.com/en/challenge/human-evolution-fieldwork-olduvai-gorge/from-oldupai-to-the-world/viewer?title_no=555118&episode_no=1">community outreach in the national language</a>, Swahili, we are delivering college education opportunities for two Maasai scholars interested in archaeology and heritage, along with several other Tanzanians.</p>
<p>The stone tools uncovered belong to the “culture” archaeologists identify as the <a href="https://www.britannica.com/topic/Oldowan-industry">Oldowan</a>. This is a landmark representing early humans that interacted with their environment in novel ways, for example, by dietary innovations combining meat and plants. In East Africa, the Oldowan started about 2.6 million years ago.</p>
<p>The concentration of stone tools and animal fossils is evidence that both humans and fauna gathered around water sources. We also learned that Oldowan hominins cast their net wide for resources. Our data reveals that early humans carried with them rocks for tools that they obtained from distant sources across the basin, 12km east. They also developed the flexibility to use various changing environments. </p>
<p>Our research reveals that the geological, sedimentary and plant landscapes around Ewass Oldupa changed a lot, and quickly. Yet humans kept coming back here to use local resources for over 200,000 years. They used a great diversity of habitats: fern meadows, woodland mosaics, naturally burned landscapes, lakeside palm groves, steppes. These habitats were regularly blanketed by ash or reworked by mass flows associated with volcanic eruptions. </p>
<p>Thanks to past and ongoing radiometric work – using the Argon method, which dates the deposition of volcanic materials that sandwich the archaeological finds – we were able to date these artefacts to a period known as the Early Pleistocene, 2 million years ago.</p>
<p>What’s not clear is which hominin species made the tools. We did not recover hominin fossils, but the remains of <em>Homo habilis</em> have been found in the younger sediments from another site just 350 metres away. It’s likely that either <em>Homo habilis</em> or a member of the genus <em>Paranthropus</em> – remains of which have also been found at Olduvai Gorge previously – was the tool maker. More research will be needed to be sure.</p>
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Read more:
<a href="https://theconversation.com/turbulent-environment-set-the-stage-for-leaps-in-human-evolution-and-technology-320-000-years-ago-148381">Turbulent environment set the stage for leaps in human evolution and technology 320,000 years ago</a>
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<h2>Collaboration</h2>
<p>One of the reasons this research is so important is that it shows, again, the value of collaboration. Archaeologists, geoscientists, biologists, chemists and material scientists were all involved in the study at Ewass Oldupa.</p>
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<p>It’s thanks to the multiple samples and artefacts these experts gathered and analysed that we also now know the adaptation to major geomorphic and ecological transformations did not have an impact on the technology hominins used. They roamed many habitats but used only one tool kit, amid unpredictable environments. </p>
<p>This is a clear sign that 2 million years ago humans were not constrained technologically and already had the capacity to expand geographic range, as they were ready to exploit a multitude of habitats within Africa – and, possibly, beyond.</p><img src="https://counter.theconversation.com/content/150755/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julio Mercader Florin receives funding from the Canadian Social Sciences and Humanities Research Council. </span></em></p>The research shows that 2 million years ago humans were not constrained technologically and already had the capacity to expand their geographic range.Julio Mercader Florin, Professor, University of CalgaryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1481872020-10-22T15:26:14Z2020-10-22T15:26:14ZNew fossil tracks belonging to human ancestors found in South Africa<figure><img src="https://images.theconversation.com/files/364687/original/file-20201021-17-197ia4s.JPG?ixlib=rb-1.1.0&rect=126%2C563%2C2824%2C1644&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A hominin track in Garden Route National Park, lightly outlined in chalk. The track is 24 centimetres long.</span> <span class="attribution"><span class="source">Charles Helm</span></span></figcaption></figure><p>Around a hundred thousand years ago, South Africa’s Cape south coast was a busy place. Giraffes, <a href="https://theconversation.com/fossil-track-sites-tell-the-story-of-ancient-crocodiles-in-southern-africa-134410">crocodiles</a>, <a href="https://theconversation.com/first-fossil-trails-of-baby-sea-turtles-found-in-south-africa-122434">hatchling sea turtles</a> and <a href="https://theconversation.com/fossil-tracks-reveal-which-birds-once-roamed-south-africas-cape-south-coast-147199">large bird species</a> populated the landscape. Early humans were there, too.</p>
<p>We know all of this because of fossil tracksites that today dot the Cape south coast, which is about 400km east of Cape Town. These sites date to between 400,000 years and 35,000 years ago, to a geological epoch known as the <a href="https://www.britannica.com/science/Pleistocene-Epoch">Pleistocene</a>. The tracks were made on dunes and beaches, which became cemented over time. These ancient surfaces, which often preserve the tracks in remarkable detail, are now amenable to our inspection and interpretation. Our research team has been documenting these tracksites since 2007. </p>
<p>A substantial body of archaeological evidence has accumulated, indicating that ancient humans on this coastline adorned themselves <a href="https://doi.org/10.1016/j.jhevol.2004.09.002">with jewellery</a>, developed sophisticated <a href="https://doi.org/10.1038/nature11660">tool technology</a>, created some of the world’s <a href="https://doi.org/10.1126/science.1067575">first engravings</a> and <a href="https://doi.org/10.1038/s41586-018-0514-3">drawings</a>, and harvested shellfish and seafood in <a href="https://doi.org/10.1038/nature06204">a co-ordinated manner</a>. In short, they exhibited many forms of modern human behaviour – and the region has <a href="https://doi.org/10.1016/j.jhevol.2010.07.011">been described</a> as a refugium in which our ancestors survived tough climatic conditions, and then thrived.</p>
<p>Our team found its first hominin tracksite in 2016. We identified 40 tracks, estimated to be around 90,000 years old and indicating a party of humans travelling fast down a dune slope. The tracks were in a small cave west of what’s now the town of Knysna. </p>
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Read more:
<a href="https://theconversation.com/ancient-humans-may-have-made-patterns-and-sculptures-on-south-africas-beaches-123546">Ancient humans may have made patterns and sculptures on South Africa's beaches</a>
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<p>Now we’ve found three further hominin tracksites – and possibly a fourth. The sites are described in a <a href="https://www.sajs.co.za/article/view/8156">recently published article</a> in the South African Journal of Science. One site, containing 32 tracks in a number of trackways, was unusual in that it we could examine both the surface on which the tracks were made (on a fallen slab near the high water mark) and, under an overhang in the cliffs above, the surface containing the infill layer. In fact, the tracks showed better preservation on the latter surface. </p>
<p>These discoveries bring the total of southern African hominin tracksites to six, following <a href="http://dx.doi.org/10.1080/10420940802470482">earlier discoveries</a> at Nahoon Point in the Eastern Cape in 1965 and at Langebaan on the West Coast in 1995. Coincidentally, in the same week that our article was published, a site with tracks from approximately the same time period, and also attributed to Homo sapiens, <a href="https://doi.org/10.1126/sciadv.aba8940">was reported</a> from the Arabian peninsula. </p>
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Read more:
<a href="https://theconversation.com/prehistoric-desert-footprints-are-earliest-evidence-for-homo-sapiens-on-arabian-peninsula-146445">Prehistoric desert footprints are earliest evidence for Homo sapiens on Arabian Peninsula</a>
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<p>Our findings provide an addition to the global hominin fossil record. The more scientists know about where human ancestors roamed, and how they behaved, the better they can understand how and where humans developed, the threats they faced and how they overcame these.</p>
<h2>What the tracks reveal</h2>
<p>The three sites we have definitively identified lie within protected areas. One is within the <a href="https://www.sanparks.org/parks/garden_route/">Garden Route National Park</a>, and two within the <a href="https://www.capenature.co.za/reserves/goukamma-nature-reserve/">Goukamma Nature Reserve</a>. This is good news because collaboration with the relevant authorities can lead to enhanced site protection and preservation.</p>
<p>Two of the sites described in our new research paper contained tracks of various sizes, suggesting the possibility of family groups. A third site contained three forefoot impressions with convincing evidence of toe impressions. Alongside these we found an array of nearly-parallel groove features and small circular depressions. These may have been made in the sand by a human using a finger or a stick.</p>
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Read more:
<a href="https://theconversation.com/fossil-footprints-the-fascinating-story-behind-the-longest-known-prehistoric-journey-147520">Fossil footprints: the fascinating story behind the longest known prehistoric journey</a>
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<p>At the fourth site we found tracks of the right size and the right pace length to suggest a human trackmaker. But they were only visible in cross section in cliff layers. We felt it prudent not to over-interpret these features and make a definite conclusion, although they were highly suggestive and occurred close to our 2016 hominin tracksite.</p>
<figure class="align-center ">
<img alt="A footprint is highlighted in red against a blue backdrop" src="https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=693&fit=crop&dpr=1 600w, https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=693&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=693&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=871&fit=crop&dpr=1 754w, https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=871&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/364688/original/file-20201021-21-1ogt021.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=871&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Photogrammetry colour mesh, infill layer showing hominin track in Garden Route National Park. Horizontal and vertical scales are in metres.</span>
<span class="attribution"><span class="source">Charles Helm</span></span>
</figcaption>
</figure>
<h2>Fleeting sites</h2>
<p>Anything that’s preserved in sand and stone is vulnerable once it’s re-exposed. Once these fossil tracksites are revealed by time and the elements, they may become rapidly eroded or even collapse into the sea. For instance, part of the ceiling of the hominin tracksite we discovered in 2016 has recently collapsed, and some of the tracks have therefore disappeared. </p>
<p>Luckily we were able to create a digital record of this site, taking more than a thousand photographs for photogrammetry, and thus generating a 3D model. This means the unique surface hasn’t been lost to science – and it will be possible to create an exact replica of it.</p>
<p>For now, we continue exploring and searching for new sites, knowing that we often enjoy just a short window in which to identify, research and document them before they are lost during storm surges.</p><img src="https://counter.theconversation.com/content/148187/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Helm 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>These ancient surfaces, which often preserve the tracks in remarkable detail, are now amenable to inspection and interpretation.Charles Helm, Research Associate, African Centre for Coastal Palaeoscience, Nelson Mandela UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1453472020-09-03T15:51:14Z2020-09-03T15:51:14ZGrass on ash: uncovering 200,000 year old beds from South Africa<figure><img src="https://images.theconversation.com/files/356042/original/file-20200902-22-5vf76h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A: Border Cave's 200,000 year old fossilised grass fragments. B: The profile section of desiccated grass bedding dating to around 43,000 years ago.</span> <span class="attribution"><span class="source">Both images copyright Lyn Wadley</span></span></figcaption></figure><p>There is a fair amount of archaeological evidence that indicates complex behaviour among our ancestors. For instance, there are <a href="https://doi.org/10.1016/J.JAS.2007.11.006">bone tools</a> that were used as hunting projectiles, for working leather or for processing plants. <a href="https://doi.org/10.1126/SCIENCE.1067575">Ochre</a> remnants were used for body and rock painting. But plants and their products have rarely been reported to embody this type of complex behaviour. </p>
<p>Now a multidisciplinary, international team of archaeologists has <a href="https://doi.org/10.1126/science.abc7239">presented evidence</a> that more than 200,000 years ago, at the dawn of our species (<em>Homo sapiens sapiens</em>) groups of humans inhabiting a cave in South Africa used grasses to create comfortable areas for sleeping and working. They also, our research suggests, understood the benefits of using ash underneath the grass to repel insects and pests.</p>
<p>Before this there was tentative evidence of bedding being constructed using tree leaves some 185,000 years ago at <a href="https://doi.org/10.4207/PA.2012.ART75">Misliya Cave in Israel</a>. Groups of Neanderthals from the Iberian Middle Paleolithic also used grasses to build their beds and rest areas about 40,000 years ago at <a href="https://doi.org/10.1016/j.jas.2010.07.010">Esquilleu Cave</a> (Cantabria, Spain). In South Africa, plant bedding has been observed at several sites but never studied or published in detail. Until now, the oldest bedding in South Africa <a href="https://doi.org/10.1126/science.1213317">came from Sibudu Cave</a> in the KwaZulu-Natal province, where modern humans used sedges (Cyperaceae) to build sleeping beds about 70,000 years ago.</p>
<p><a href="https://doi.org/10.1126/science.abc7239">Our research</a>, led by Professor Lyn Wadley of the University of the Witwatersrand in Johannesburg, now shows that before 200,000 years ago – close to the origin of our species – people preferred the use of broad-leaved grasses to build their beds and resting areas. They also used fire, ash, and medicinal plants to maintain clean, pest-free camps. </p>
<p>The construction of this bedding itself comes as no surprise: many animals such as chimpanzees or birds construct their beds and nests with plants. At our study site, it is the presence of ash layers underneath the bedding that demonstrates a more elaborate behaviour.</p>
<p>These findings are important because they show that our ancestors were able to organise the space and the capacity of these early societies to develop strategies that would have had health benefits, improving their daily living conditions. This helps us to understand them better, and to develop our understanding of where we’ve come from in terms of cognition and spatial awareness.</p>
<h2>Plants, people and the archaeological record</h2>
<p>Plants are the most common resource exploited by hunter-gatherers. They provide a source of food and water, beverages, medicines, poison and firewood, tools for hunting, fishing, storage and transport of food and goods, shelter and protection. Plants can also be used for numerous other purposes related to social beliefs and rituals, such as making ornaments from seeds; to make musical instruments; statuary and other decorative and symbolic objects.</p>
<p>There is little archaeological data on the types of plants and the different uses that were given to them by hunter-gatherer populations during prehistory. Globally, this is probably related to bad preservation of plant remains in the archaeological record. In South Africa, interest <a href="https://doi.org/10.2307/3888947">in studying</a> botanical remains peaked in the late 1980s and early 1990s; few archaeobotanical studies have been conducted since then. There is a need for a better understanding of prehistoric plant use in South Africa. </p>
<p>Our research was conducted in <a href="https://doi.org/10.1080/00934690.2018.1504544">Border Cave</a>, located on a cliff between eSwatini and KwaZulu-Natal in South Africa. It is a Middle Stone Age site that preserves human occupation dating from between 38,000 years and about 250,000 years ago.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=479&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=479&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=479&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=601&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=601&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355549/original/file-20200831-17-d112hc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=601&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Clockwise from top: a panoramic photograph of Border Cave (copyright: Ashley Kruger); the view from the cave (copyright: Paloma de la Peña) and excavations at Border Cave (copyright: Paloma de la Peña).</span>
</figcaption>
</figure>
<p>Some parts of the site have exceptional organic preservation: desiccated grass bedding, wood charcoal and charred rhizomes (rootstalks) from fires occur in different layers. The botanical remains we recovered in our research were preserved as ephemeral traces of silicified grass in the cave’s oldest deposits, dating back to around 200,000 years.</p>
<p>These siliceous remains are known as <a href="https://phytoliths.org/">phytoliths</a>, taken from the Greek (<em>phyto</em>, plant; <em>litho</em>, stone) – microscopic remains of silica that reproduce the cellular structure of certain plants. We discovered that Border Cave is home to the highest concentration of phytoliths documented to date in the archaeological record. This high phytolith concentration is due to their good state of preservation and an intentional and intensive accumulation of grasses for bedding construction. These phytoliths tell us about the bedding our ancestors used in the cave.</p>
<h2>Ancient bedding</h2>
<p>The beds we identified at Border Cave were constructed with broad-leaved grasses from the <em>Panicoideae</em> subfamily, and were used both for resting and to prepare daily workspaces. We know that people worked as well as slept on the grass mats because we identified debris from stone tool manufacture and red and orange ochre microfragments mixed with the grass remains that could well have been used for body decoration or on worn objects.</p>
<p>Using archaeobotanical, microscopic and infrared techniques, we identified sequences of burning and grass bedding indicating that people used this space repeatedly. We know the beds were periodically burned through the presence of ash, as well as burnt grass, wood and bone. Some of that burned wood came from the broad-leaved camphor bush (<em>Tarchonanthus</em>), a species still used as an insect repellent in parts of East Africa.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=219&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=219&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=219&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=275&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=275&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356038/original/file-20200902-14-7cdqcj.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=275&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Plant composition of the 200,000 year old bedding. A, Microphotograph of Panicoideae grass phytoliths; Copyright, Irene Esteban. B, Scanning electron microscope image of Panicoideae grass fragment; Copyright, Lyn Wadley. C, Photograph of modern Panicum maximum grass; Copyright, Lyn Wadley.</span>
</figcaption>
</figure>
<p>It is likely that most of these plants were infested by ticks, among other insects and pests, as is the case today. Ticks carry many diseases, and it is probable that our human ancestors would suffer from their bites. We speculate that laying grass bedding on ash was a deliberate strategy not only to create a dirt-free, insulated base for the bedding, but perhaps also to repel crawling insects. </p>
<p>Sometimes the ashy layer underneath the bedding was a remnant of older grass bedding that had been burned to clean the cave and destroy pests. In more recent occupations, wood ash from fireplaces was probably used as the clean surface for a new bedding layer.</p><img src="https://counter.theconversation.com/content/145347/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Irene Esteban receives funding from the University of the Witwatersrand, The Palaeontological Scientific Trust, DSI/NRF Centre of Excellence in Palaeosciences and the USA National Science Foundation.
She is also an affiliated member of the African Centre of Coastal Palaeosciences.</span></em></p><p class="fine-print"><em><span>Paloma de la Peña Alonso receives funding from the DSI/NRFCenter of Excellence of Paleosciences and the Paleontological Scientific Trust. </span></em></p>Before 200,000 years ago, close to the origin of our species, people preferred the use of broad-leaved grasses to build their beds and resting areas using ash layers underneath.Irene Esteban, Post-doctoral Research Fellow, University of the WitwatersrandPaloma de la Peña Alonso, Senior Researcher in African Quaternary Archaeology and Hominin Palaeoecology (University of Cambridge and University of the Witwatersrand), University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1453432020-09-01T06:55:59Z2020-09-01T06:55:59ZPioneering archaeologist Revil Mason leaves an immeasurable legacy<figure><img src="https://images.theconversation.com/files/355546/original/file-20200831-19-i5i70r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Revil Mason remained passionate about archaeology throughout his life.</span> <span class="attribution"><span class="source">Supplied</span></span></figcaption></figure><p>“Brilliant, creative, unpredictable, sometimes difficult, humorous, an indefatigable field archaeologist.” That’s how the late Professor Phillip Tobias once described his fellow archaeologist Professor Revil John Mason, who passed away in Johannesburg on 23 August 2020. Mason was 91 years old.</p>
<p>I had the honour of learning more about Mason – the man and the archaeologist – in February 2019 when the <a href="https://www.wits.ac.za/origins/">Origins Centre</a> at the University of the Witwatersrand (Wits) in Johannesburg hosted an exhibition that celebrated his immense contribution to southern African archaeology. It’s hard to believe that the enthusiastic, sharp and able man with an incredible memory and deep knowledge is no longer with us.</p>
<h2>Mapping history</h2>
<p>Mason was born on 10 February 1929. He grew up in Saxonwold, Johannesburg, and attended St John’s College, from which he matriculated in 1946. He studied a B.Com at Wits and excelled, receiving numerous accolades and awards. But a different path awaited him. </p>
<p>After attending a lecture by world famous anatomist Professor Raymond Dart a young Revil Mason became fascinated by archaeology and went to the University of Cape Town to study the subject. Again, he was an excellent student and went on to obtain his doctorate in archaeology in 1957, when he was 28. He worked for the country’s Archaeological Survey until he took an archaeological position at Wits in the 1960s.</p>
<p>The institution became Mason’s academic home for the rest of his working life. He became a professor, and in 1976 was appointed as the founding director of the Archaeological Research Unit. It was a post he held until his retirement in 1989. With the unit, he launched an extensive survey and excavation programme and was instrumental in laying the foundation for the practice of archaeology in South Africa.</p>
<p>Together with colleagues, he excavated numerous Early, Middle and Later Stone Age (hunter-gatherer) sites dating back to almost 2.6 million years, as well as agriculturalist and herder (Iron Age and historic) sites, mostly around the Gauteng and North West provinces. Among them were Makapansgat, Cave of Hearths, Sterkfontein, Olieboomspoort, Kalkbank, Munro, Uitkomst, Melville Koppies, the Kruger Cave (later called the Mohale Cave) and Broederstroom.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355548/original/file-20200831-17-1ejnd01.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">
<figcaption>
<span class="caption">Revil Mason (centre) with fellow members of the Wits Archaeology Research Unit Tom Maubane (left) and Lewis Matileya at Zambok, a site discovered by Maubane near Haartebeest Poort.</span>
<span class="attribution"><span class="source">Supplied</span></span>
</figcaption>
</figure>
<p>Mason introduced and demonstrated the value of various analytical methods into the field of archaeology. Under his directorship, the Archaeological Research Unit undertook smelting furnace experiments, to better understand the furnaces found at Melville Koppies and Lonehill – some of which are still there today. He also saw the value of aerial photography in discovering and recording archaeological sites; by combining this with many hours of excavating, he <a href="https://www.researchgate.net/profile/Revil_Mason">mapped</a> the Herder (Iron Age) archaeology of the entire North West and Gauteng provinces. </p>
<p>He published numerous papers and books, which are still read and used today. His books included <a href="https://books.google.co.za/books/about/Cave_of_Hearths_Makapansgat_Transvaal.html?id=b9IKAQAAIAAJ&redir_esc=y">Cave of Hearths</a> (1988), <a href="https://www.worldcat.org/title/origins-of-black-people-of-johannesburg-and-the-southern-western-central-transvaal-ad-350-1880/oclc/17539135">Origins of Black People of Johannesburg Area</a> (1987), and South African Archaeology 1922-1988 (1989).</p>
<p>His work mapping Herder archaeology clearly demonstrated evidence for well-connected and thriving communities involved in trade and significant agricultural endeavours, long before European colonisers arrived in South Africa.</p>
<p>This fitted with his then progressive ideas about the importance of making all South Africans aware of the country’s archaeological past. During the 1980s historians and archaeologists began to challenge the fallacy of European colonial myths perpetuated in the school history curriculum. Mason tirelessly sought to convince officials of the need to recognise and celebrate the African past, and the role that African people played in the making of modern South African society. He welcomed school groups to visit the sites he was excavating, and worked with teachers to develop programmes to help learners understand how people lived in South Africa in the last 2,000 years.</p>
<h2>Rock art</h2>
<p>With his colleagues, Mason investigated the beautiful rock engravings in the Magaliesberg near Johannesburg, which are now curated by the <a href="https://www.wits.ac.za/rockart/">Rock Art Research Institute</a> at Wits and some of which are on display at Origins Centre. </p>
<p>At the age of 25, Mason climbed the Brandberg mountains in Namibia looking for rock art made by the indigenous San people. He discovered what he called “the Brandberg Picasso”, an abstract San rock art image, and documented a San rock art site on top of the Brandberg in a cave now known as Mason shelter. Together with revered artist Judith Menger (whom he married in 1957), the sites were meticulously traced and, later, beautiful replica paintings were made. </p>
<figure class="align-center ">
<img alt="Supplied" src="https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355547/original/file-20200831-16-1it9px9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A young Revil Mason surveying for Professor C. Van Riet Louw.</span>
</figcaption>
</figure>
<p>He didn’t just climb for work. Mason was a keen explorer and mountaineer. He explored Kaokoland and the Brandberg in Namibia, the Ruwenzori in Uganda, and other African mountains. He hiked the great Asian mountains, climbed the ice mountains in Russia and the Pamirs in Central Asia. He cycled down North America from Canada to Mexico, and at the age of 69 went on a solo bike trip across the Karakoram Mountains, in the western Himalayas, from Pakistan to China.</p>
<p>Mason, who is survived by two daughters, Tamar and Petra Mason, and two grandchildren – was a driven yet humble and down to earth man. He lived his life simply, often preferring to cook food on an open fire: in fact, his braai grid was on display at the Origins Centre’s exhibition.</p>
<p>He will be sorely missed. But he will not be forgotten: Revil John Mason has left an incredible legacy and has inspired many to become (better) archaeologists, instilling a passion for exploring the real African history. His contribution to archaeology and towards an accurate understanding of South African history is immeasurable.</p><img src="https://counter.theconversation.com/content/145343/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tammy Hodgskiss 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>Mason tirelessly sought to convince officials of the need to recognise and celebrate the African past, and the role that African people played in the making of modern South African society.Tammy Hodgskiss, Curator at the Origins Centre Museum, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1438092020-08-24T14:48:51Z2020-08-24T14:48:51ZWhat archaeology tells us about the music and sounds made by Africa’s ancestors<figure><img src="https://images.theconversation.com/files/354099/original/file-20200821-18-lf1c0l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Music has been part and parcel of humanity for a long time. Not every sound is musical, but sound has meaning and sometimes the meaning of sound is specific to its context. </p>
<p>But when it comes to archaeology there is scant evidence of music or sound producing artefacts from southern Africa. This is because of poor preservation of the mostly organic materials that were used to manufacture musical instruments. Rock art offers depictions of musical instruments as well as scenes of dancing that can be linked with music performance, but here only music-related artefacts will be discussed.</p>
<p>I conducted original research as well as a survey of the literature available on these artefacts. Ethnographic sources were also consulted in order to attempt to provide a broader contextual background against which knowledge of the archaeological implements could be expanded. The <a href="https://muse.jhu.edu/book/60594">Percival Kirby</a> online musical instrument <a href="https://digitalcollections.lib.uct.ac.za/percival-kirby-musical-instruments">repository</a> has also been used. Music archaeology is multidisciplinary in nature. </p>
<p>The result is one of the <a href="https://www.tandfonline.com/doi/full/10.1080/0067270X.2020.1761686?casa_token=z6HOLccq43UAAAAA%3A6WDeEMhfWxKHzlYrtG0qcAb_IeAKhVNKZKbOlJsHabLol56zzmHJqytRlAZrQRhm4eHR4B_SBNyfLJ0">first reports</a> on southern African sound- and music-related artefacts.</p>
<p>Research in music archaeology in southern Africa has just begun. Available evidence dates back from around 10,000 years ago, from the Later Stone Age up to the Iron Age. The artefacts fall into two groups, namely <a href="https://www.britannica.com/art/aerophone">aerophones</a>, where sound is produced by vibrating air, and <a href="https://www.britannica.com/art/idiophone">idiophones</a>, where sound is produced by solid material vibrating. These artefacts include spinning disks, bullroarers, bone tubes that could have been used as flutes or whistles, clay whistles, keys from thumb pianos (also called lamellophones or mbiras), musical bells and an ivory trumpet. The list is not exhaustive and more research needs to be conducted.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man and a woman warmly dressed sorting through dug up objects in a cave." src="https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354105/original/file-20200821-22-11ijl2w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The author and Professor Sarah Wurz digging at Klasies River.</span>
<span class="attribution"><span class="source">Supplied</span></span>
</figcaption>
</figure>
<p>These music-related or sound-producing artefacts are made from various materials, including bone, ivory, metal and clay. The artefacts show how integral sound and music production was in the socio-cultural practices of people in the past, most likely for entertainment and rituals. Sound production and music making is a sign of being fully human.</p>
<h2>Aerophones</h2>
<p>Recent experimental work <a href="https://www.sciencedirect.com/science/article/abs/pii/S2352409X18307612?casa_token=I77Wl8CEl-sAAAAA:MzDQ9oy-A-D6OiAUrNyfw73uOcq_dTGkFHXRRSEmpAoZCoqfjQvmc49q1r_22-AzLtUU-U_728YJ">established</a> that some Later Stone Age bone implements from the <a href="https://www.sciencedirect.com/science/article/abs/pii/S2352409X18307612?via%3Dihub">Klasies River</a> Mouth and <a href="https://www.worldcat.org/title/prehistory-of-the-matjes-river-rock-shelter/oclc/4681377">Matjes River</a> sites are a spinning disk and a bullroarer respectively. Their replicas produced powerful whirring sounds and they can be referred to as <a href="https://theconversation.com/how-our-african-ancestors-made-sound-in-the-stone-age-121142">sound-producing</a> implements even though the purpose of the sound or their use cannot be clearly ascertained. They could have been used as signalling implements, toys, in ritual settings or in musical contexts, among others. Nowadays these implements are seldom found in the region.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A flat disc shaped like a mollusc with a hole through its thin end." src="https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=320&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=320&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=320&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=402&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=402&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354111/original/file-20200821-18-qwblwr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=402&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bullroarer found at Matjes River.</span>
<span class="attribution"><span class="source">Joshua Kumbani</span></span>
</figcaption>
</figure>
<p>Bone tubes, mainly in bird bone, have been recovered from Later Stone Age contexts from the southern and western Cape of South Africa and some were also recovered from historical contexts. Previously, these bone tubes were interpreted as sucking tubes and beads. But morphological analysis – or studying their form – has indicated that considering the various lengths and widths as well as their smoothened ends, they could have been used as flutes or whistles. There is no a clear-cut distinction between flutes and whistles. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Brown flute-like tube with etchings on it." src="https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=283&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=283&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=283&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=355&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=355&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354112/original/file-20200821-22-deggds.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=355&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bone tube from Matjie’s River.</span>
<span class="attribution"><span class="source">Joshua Kumbani</span></span>
</figcaption>
</figure>
<p>If they were used as flutes they were single tone flutes since none has finger holes that can enable the production of more tones. Some of the archaeological bone tubes bear chevron and cross hatching patterns, but it is not clear if the decorations have a meaning or were just made for aesthetic purposes. The <a href="https://www.britannica.com/topic/San">San</a> and Khoe people in South Africa used reed flutes in the past. Flutes are still used today by various cultural groups in South Africa, for example the Venda people in South Africa use flutes when performing the <em><a href="http://era.anthropology.ac.uk/Era_Resources/Era/VendaGirls/Definitions/DefTshikona.html">tshikona</a></em> dance. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Round, brown acorn-like object with a hole in one end." src="https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=591&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=591&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=591&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=742&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=742&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354114/original/file-20200821-16-d4z2eq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=742&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Clay whistle from Mapungubwe.</span>
<span class="attribution"><span class="source">Joshua Kumbani</span></span>
</figcaption>
</figure>
<p>Clay whistles have been recovered from the sites of K2 and Mapungubwe from Early Iron Age contexts. Similar clay whistles are very rare and are not mentioned ethnographically, but it has been said that the Basotho herders in Lesotho used similar whistles. Whistles can also be used during a musical procession or as signalling implements in sending a message.</p>
<p>An ivory trumpet was recovered from Sofala site in Mozambique. It has a blow hole and some decorations on its body. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Intricately carved brown object." src="https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=220&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=220&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=220&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=276&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=276&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354115/original/file-20200821-16-17c8x51.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=276&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ivory trumpet from Sofala site in Mozambique.</span>
<span class="attribution"><span class="source">University of Pretoria Museums</span></span>
</figcaption>
</figure>
<p>Ivory trumpets are not common in southern Africa, but are known in west Africa. For example, in Ghana among the Asante people they had a spiritual significance and were associated with the royal court. Ivory trumpets are also said to have been used to announce the arrival of kings. The trumpets that are found in southern Africa are not in ivory. </p>
<h2>Idiophones</h2>
<p>Thumb piano, lamellophone or mbira keys have been recovered from the Later Iron Age contexts in Zimbabwe and in Zambia. This idiophone became popular with the introduction of iron technology and it is still used today. Some popular musicians play the lamellophone, for example <a href="https://www.stellachiweshe.com">Stella Chiweshe</a> from Zimbabwe. Mbira is closely associated with spirituality, especially among the Shona people of Zimbabwe. The lamellophone is now a common musical instrument globally.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small, brown, rusty metal object in the shape of an oar." src="https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=236&fit=crop&dpr=1 600w, https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=236&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=236&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=297&fit=crop&dpr=1 754w, https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=297&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/354117/original/file-20200821-22-ereyve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=297&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Thumb piano key from Great Zimbabwe site.</span>
<span class="attribution"><span class="source">Foreman Bandama</span></span>
</figcaption>
</figure>
<p>Musical bells were found in South Africa, Zimbabwe and Zambia from Later Iron Age contexts. Both double and single bells existed and, for example, at Great Zimbabwe both were recovered. Ethnographically, musical bells are known to have originated in West and Central Africa and they were most likely introduced to southern Africa through trade. These idiophones are said to have been played to announce the arrival of kings. Musical bells are still used today.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-our-african-ancestors-made-sound-in-the-stone-age-121142">How our African ancestors made sound in the Stone Age</a>
</strong>
</em>
</p>
<hr>
<p>Musical instruments are seldom found in the archaeological record and are not easily identifiable, so there is a lot of debate among researchers when it comes to identifying these instruments from the archaeological record. Some instruments may not have been musical instruments per se but rather sound-producing implements that were used to convey certain messages or used for ritual purposes.</p><img src="https://counter.theconversation.com/content/143809/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joshua Kumbani is a PhD candidate at the University of the Witwatersrand and is a bursary recipient of the Re-Centring AfroAsia Project: Musical and Human Migrations in the Pre-Colonial Period 700-1500 AD that is funded by the Andrew W. Mellon Foundation. </span></em></p>There is not much information on artefacts used by Stone Age humans to make sound and music – but the first comprehensive survey is a good start.Joshua Kumbani, PhD Candidate, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1436202020-08-12T20:13:03Z2020-08-12T20:13:03ZFrom cave art to climate chaos: how a new carbon dating timeline is changing our view of history<figure><img src="https://images.theconversation.com/files/352428/original/file-20200812-23-cpm0hy.jpg?ixlib=rb-1.1.0&rect=150%2C110%2C6559%2C4355&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Geological and archaeological records offer important insights into what seems to be an increasingly uncertain future. </p>
<p>The better we understand what conditions Earth has already experienced, the better we can predict (and potentially prevent) future threats. </p>
<p>But to do this effectively, we need an accurate way to date what happened in the past. </p>
<p>Our research, published today in the journal <a href="https://www.cambridge.org/core/journals/radiocarbon/calibrations/intcal-20">Radiocarbon</a>, offers a way to do just that, through an updated method of calibrating the <a href="https://c14.arch.ox.ac.uk/dating.html">radiocarbon timescale</a>.</p>
<h2>An amazing tool for perusing the past</h2>
<p>Radiocarbon dating has revolutionised our understanding of the past. It is nearly 80 years since Nobel Prize-winning US chemist Willard Libby <a href="https://www.nature.com/articles/d41586-019-01895-z">first suggested</a> minute amounts of a radioactive form of carbon are created in the upper atmosphere. </p>
<p>Libby correctly argued this newly formed radiocarbon (or C-14) rapidly converts to carbon dioxide, is taken up by plants during photosynthesis, and from there travels up through the food chain. </p>
<p>When organisms interact with their environment while alive, they have the same proportion of C-14 as their environment. Once they die they stop taking in new carbon.</p>
<p>Their level of C-14 then halves every 5,730 years due to <a href="https://www.esrl.noaa.gov/gmd/ccgg/isotopes/decay.html">radioactive decay</a>. An organism that died yesterday will still have a high level of C-14, whereas one that died <a href="https://www.acs.org/content/acs/en/education/whatischemistry/landmarks/radiocarbon-dating.html">tens of thousands of years ago will not</a>. </p>
<p>By measuring the level of C-14 in a specimen, we can deduce how long ago that organism died. Currently, with <a href="https://www.nature.com/articles/d41586-019-01895-z">this method</a>, we can date remains up to 60,000 years old.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-what-is-radiocarbon-dating-and-how-does-it-work-9690">Explainer: what is radiocarbon dating and how does it work?</a>
</strong>
</em>
</p>
<hr>
<h2>A seven-year effort</h2>
<p>If the level of C-14 in the atmosphere had always been constant, radiocarbon dating would be straightforward. But it hasn’t.</p>
<p>Changes in the <a href="https://wserv4.esc.cam.ac.uk/pastclimate/?page_id=19">carbon cycle</a>, impinging <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/cosmic-radiation">cosmic radiation</a>, the <a href="https://www.pnas.org/content/112/31/9542">use of fossil fuels</a> and <a href="https://theconversation.com/anthropocene-began-in-1965-according-to-signs-left-in-the-worlds-loneliest-tree-91993">20th century nuclear testing</a> have all caused large variations over time. Thus, all radiocarbon dates need to be adjusted (or calibrated) to be turned into accurate calendar ages.</p>
<p>Without this adjustment, dates could be out by up to 10-15%. <a href="https://www.cambridge.org/core/journals/radiocarbon/calibrations">This week we report</a> a seven-year international effort to recalculate three radiocarbon calibration curves: </p>
<ul>
<li>IntCal20 (“20” to signify this year) for objects from the northern hemisphere</li>
<li>SHCal20 for samples from the ocean-dominated southern hemisphere</li>
<li>Marine20 for samples from the world’s oceans.</li>
</ul>
<figure class="align-right ">
<img alt="Close-up of bristlecone pine tree rings." src="https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352243/original/file-20200811-20-1ciaghc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">We dated bristlecone pine tree rings from the second millennium BC.</span>
<span class="attribution"><span class="source">P. Brewer/Uni of Arizona</span></span>
</figcaption>
</figure>
<p>We constructed these updated curves by measuring a plethora of materials that record past radiocarbon levels, but which can also be dated by other methods. </p>
<p>Included in the archives are tree rings from ancient logs preserved in wetlands, cave stalagmites, corals from the continental shelf and sediments drilled from lake and ocean beds. </p>
<figure class="align-center ">
<img alt="An ancient New Zealand kauri tree log." src="https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/351532/original/file-20200806-24-1vpdpwj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ancient New Zealand kauri (<em>Agathis australis</em>) logs like this example were used to help construct the calibration curves. This tree is about 40,000 years old and was found buried underground.</span>
<span class="attribution"><span class="source">Nelson Parker</span></span>
</figcaption>
</figure>
<p>In total, the new curves are based on almost 15,000 radiocarbon measurements taken from objects up to 60,000 years old.</p>
<p>Advances in radiocarbon measurement using <a href="https://en.wikipedia.org/wiki/Accelerator_mass_spectrometry">accelerator mass spectrometry</a> mean the updated curves can use very small samples, such as single tree rings from just one year’s growth.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of an ancient stalagmite." src="https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=177&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=177&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=177&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=223&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=223&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352423/original/file-20200812-20-685xzm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=223&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Stalagmites from inside the Hulu Cave in China were key to estimating the amount of radiocarbon present in objects between 14,000 and 55,000 years old.</span>
<span class="attribution"><span class="source">Hai Cheng</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Reassessing old beliefs</h2>
<p>The new radiocarbon calibration curves provide previously impossible precision and detail. As a result, they greatly improve our understanding of how Earth has evolved and how these changes impacted its inhabitants.</p>
<p>One example is the rate of environmental change at the end of the most recent ice age. As the world started to warm some 18,000 years ago, vast ice sheets covering Antarctica, North America (including Greenland) and Europe melted – returning huge volumes of fresh water to the oceans.</p>
<p>But the sea level didn’t rise at a consistent rate like the global temperature. Sometimes it was gradual and other times extremely rapid.</p>
<p>A prime location to detect past sea levels is the <a href="https://www.britannica.com/place/Sunda-Shelf">Sunda Shelf</a>, a large platform of land that was once part of continental Southeast Asia.</p>
<p><a href="https://science.sciencemag.org/content/288/5468/1033.full">One study</a> published in 2000 showed mangrove plant remains found on the seabed recorded a catastrophic 16-metre sea level rise over several hundred years (about half a metre each decade). This event, known as <a href="https://www.giss.nasa.gov/research/briefs/gornitz_10/">Meltwater Pulse-1A</a>, flooded the Sunda Shelf. </p>
<p>Our latest work has modified this story considerably. The new calibration curves reveal this extreme phase of sea level rise actually began 14,640 years ago and lasted just 160 years. </p>
<p>This equates to a staggering one-metre rise each decade – a sobering lesson for the future, considering the current much lower <a href="https://www.theguardian.com/environment/2020/may/08/sea-levels-could-rise-more-than-a-metre-by-2100-experts-say">projected changes for the end of this century</a>. </p>
<h2>An extra half a millennium of art</h2>
<p>Going further back in time, we also looked at some of the world’s oldest cave art in France’s <a href="https://archeologie.culture.fr/chauvet/en">Chauvet Cave</a>, first discovered in 1994. </p>
<p>This cave contains hundreds of beautifully preserved paintings. They depict a European menagerie with long-extinct mammoths, cave lions and woolly rhinoceroses, captured in real-life scenes that provide a window into a lost world.</p>
<p>The Chauvet Cave reveals the artistic sophistication of our <a href="http://www.bradshawfoundation.com/chauvet/index.php">early ancestors</a> in phenomenal detail.</p>
<figure class="align-center ">
<img alt="Chauvet cave paintings depicting wild animals including horses." src="https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=595&fit=crop&dpr=1 600w, https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=595&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=595&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=747&fit=crop&dpr=1 754w, https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=747&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/351623/original/file-20200806-20-11fv1gc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=747&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Chauvet Cave contains hundreds of cave paintings created more than 30,000 years ago.</span>
<span class="attribution"><span class="source">Thomas T/flickr</span></span>
</figcaption>
</figure>
<p>With the new IntCal20 curve, our best estimate for the creation of the oldest radiocarbon-dated painting in the cave is now 36,500 years ago. This is almost 450 years older than previously thought.</p>
<p>These are just two of many more examples of the far-reaching impact our latest work will have. </p>
<p>As <a href="https://www.cambridge.org/core/journals/radiocarbon/calibrations">the new calibration curves</a> are used to re-analyse ages of a host of archaeological and geological records, we can expect major shifts in our understanding of the planet’s past – and hopefully, a better forecast into its future. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-that-rock-hashtag-really-the-first-evidence-of-neanderthal-art-31238">Is that rock hashtag really the first evidence of Neanderthal art?</a>
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<img src="https://counter.theconversation.com/content/143620/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Turney receives funding from The Australian Research Council and is a scientific advisor to cleantech graphite company, CarbonScape (<a href="https://www.carbonscape.com">https://www.carbonscape.com</a>).</span></em></p><p class="fine-print"><em><span>Alan Hogg receives funding from the Marsden fund administered by the Royal Society of New Zealand. </span></em></p><p class="fine-print"><em><span>Paula J. Reimer receives funding from the Leverhulme Trust and UK Research and Innovation. </span></em></p><p class="fine-print"><em><span>Tim Heaton receives funding from the Leverhulme Trust via a research fellowship on "Improving the Measurement of Time via Radiocarbon". </span></em></p>The updated methods are providing a clearer picture of how Earth and its inhabitants evolved over the past 60,000 years - and thus, providing new insight into its future.Christian Turney, Professor, Earth Science and Climate Change, UNSW SydneyAlan Hogg, Professor, Director, Carbon Dating Laboratory, University of WaikatoPaula J. Reimer, Chair professor, Queen's University BelfastTim Heaton, Lecturer in Statistics, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1376512020-05-17T08:51:39Z2020-05-17T08:51:39ZWhat a bone arrowhead from South Africa reveals about ancient human cognition<figure><img src="https://images.theconversation.com/files/332256/original/file-20200504-83779-1rfism2.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The bone arrowhead (insert) found at Klasies River main site has much to teach us.</span> <span class="attribution"><span class="source">Justin Bradfield and Sarah Wurz</span></span></figcaption></figure><p>The origin of bow hunting has been a <a href="https://www.smithsonianmag.com/science-nature/early-bow-and-arrows-offer-insight-into-origins-of-human-intellect-112922281/">hotly debated</a> topic in archaeology for the past two decades. This is because knowing when it emerged has the potential to offer insights into the development of human cognition and the early development of complex technology.</p>
<p>Bone arrowheads were used throughout most of the world for the last few thousand years. But the examples found in South Africa predate anything from other regions by at least 20 000 years. Currently, the earliest evidence of bow hunting technology outside Africa comes from <a href="https://www.nature.com/articles/s41559-019-0990-3">southern Europe</a>, and dates to around 45 000 years ago. The earliest non-African evidence of bone points used as arrow tips is at 35 000 years ago from <a href="https://www.sciencedirect.com/science/article/abs/pii/S0047248413002467">Timor Island</a>.</p>
<p>Because bows and arrows were made predominantly from organic materials, very little evidence of these weapons survives archaeologically. Nevertheless, at several sites in South Africa small <a href="https://www.sciencedirect.com/science/article/pii/S0305440311001233">stone segments</a> have been found from 60 000-year-old horizons that are thought to have once formed part of arrowheads, either as tips or barbs.</p>
<p>Bow and arrow technology gives hunters a unique advantage over their prey. It allows them to hunt from a distance, and from a concealed position. This, in turn, increases individual hunters’ success, as well as providing an aspect of safety when stalking dangerous prey such as buffalo, bushpig, or carnivores.</p>
<p>The bow and arrow consists of multiple parts, each with a particular function and operating together to make hunting possible. This kind of “symbiotic” technology requires a high degree of <a href="https://www.oxfordscholarship.com/view/10.1093/oso/9780190854614.001.0001/oso-9780190854614-chapter-23">cognitive flexibility</a>: the mental ability to switch between thinking about different concepts, and to think about multiple concepts simultaneously. </p>
<p>Until now, evidence for bow hunting technology using bone and dating back more than 60 000 years has only been <a href="https://www.sciencedirect.com/science/article/pii/S0305440307002142">reported</a> from South Africa’s KwaZulu-Natal region. Now an <a href="https://www.sciencedirect.com/science/article/abs/pii/S0277379120302572">in-depth examination</a> of a bone arrowhead found in South Africa’s Eastern Cape province extends the known distribution of this technology farther south – and slightly earlier than previously thought. </p>
<h2>The artefact</h2>
<p>Our study, published in <a href="https://www.sciencedirect.com/science/article/abs/pii/S0277379120302572">Quaternary Science Reviews</a>, focused on a long, thin, delicately made, pointed bone artefact. It was found at the Klasies River Main site, along the Eastern Cape coast of South Africa. </p>
<p>This is an extremely important archaeological site. It has the most prolific assemblage of <a href="https://www.sciencedirect.com/science/article/abs/pii/S0047248416302305"><em>H. sapiens</em> remains</a> in sub-Saharan Africa, spanning the last 120 000 years. Its archaeology sparked the first discussions raising the <a href="https://scholar.google.com/scholar_lookup?title=A%C2%A0late%20Pleistocene%20archive%20of%20life%20at%20the%20coast%2C%20Klasies%20River&author=H.J.%20Deacon&publication_year=2005&pages=130-149">probability</a> that complex human behaviour and cognition were represented in sub-Saharan Africa long before appearing in Eurasia.</p>
<p>The artefact we studied, which comes from deposits dated to more than 60 000 years ago, closely resembles thousands of bone arrowheads used by the indigenous San hunter-gatherers from the 18th to the 20th centuries. It was excavated in the 1960s, but its importance was not recognised until recently, owing to confusion surrounding its age.</p>
<p>Our study followed a combined approach, incorporating microscopic analysis of the bone surface, high-resolution computed tomography (CT), and non-destructive chemical analysis. The study found trace amounts of a black, organic residue distributed over the surface of the bone point in a manner suggestive of 20th century poisoned arrows. The chemistry of the black substance indicates it consists of many ingredients. Again, this is suggestive of known San poison and glue recipes.</p>
<p>We still do not know exactly what organic compounds went into the recipe for the black substance, but future chemistry work will address this question.</p>
<p>Microscopic analysis of the bone artefact indicates that it was hafted (or attached) to another arrow section – probably into a reed shaft. This was done after the black residue was applied. The micro-CT scan allowed us to look inside the bone, to see structural damage at a microscopic scale. These results showed that the bone artefact had experienced the same mechanical stresses as high-velocity projectiles, like arrows.</p>
<p>The study demonstrates that the pointed bone artefact from Klasies River was certainly hafted, maybe dipped in poison, and used in a manner similar to identical bone points from more recent contexts.</p>
<p>The artefact also fits in with what we know of ancient people’s cognition and abilities in southern Africa.</p>
<p>From at least 100 000 years ago people in southern Africa were combining multiple ingredients to form coloured pastes, possibly for <a href="https://science.sciencemag.org/content/334/6053/219">decoration</a> or <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0136090">skin protection</a>. By 70 000 years ago they were making glues and other compound <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0140269">adhesives</a> using a range of ingredients, combined in a series of complex steps. These glues may have then been used, among other things, to <a href="https://www.sciencedirect.com/science/article/pii/S0305440311001233">haft</a> small stone pieces in varying arrangements, probably as insets for arrows or other weapons. </p>
<p>The presence of these technical elements in the southern African Middle Stone Age (roughly equivalent to the Eurasian Middle Palaeolithic) signals an advanced cognitive ability. That includes notions of abstract thought, analogical reasoning, multitasking and <a href="https://www.tandfonline.com/doi/abs/10.1080/0067270X.2015.1039236">cognitive fluidity</a> or the ability to ‘think outside the box’.</p><img src="https://counter.theconversation.com/content/137651/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Justin Bradfield receives funding from the National Research Foundation. </span></em></p><p class="fine-print"><em><span>Jerome Reynard receives funding from the National Research Foundation.</span></em></p><p class="fine-print"><em><span>Marlize Lombard received funding from the African Origins Platform of the National Research Foundation of South Africa. </span></em></p><p class="fine-print"><em><span>Sarah Wurz receives funding from the Centre of Excellence in Palaeoscience, University of the Witwatersrand</span></em></p>The artefact comes from deposits dated to more than 60,000 years ago. It closely resembles thousands of bone arrowheads used by the indigenous San hunter-gatherers from the 18th to the 20th centuries.Justin Bradfield, Senior lecturer, University of JohannesburgJerome Reynard, Lecturer in Osteoarchaeology, University of the WitwatersrandMarlize Lombard, Professor with Research Focus in Stone Age Archaeology, Palaeo-Research Institute, University of JohannesburgSarah Wurz, Professor, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1305352020-04-01T19:08:55Z2020-04-01T19:08:55ZBaby steps: this ancient skull is helping us trace the path that led to modern childhood<figure><img src="https://images.theconversation.com/files/324205/original/file-20200331-65495-1u437rv.jpg?ixlib=rb-1.1.0&rect=29%2C39%2C3265%2C2356&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The original Dikika child skull (left), a 3D model produced with synchrotron scanning (middle), and a model corrected for distortion during fossilisation (right).</span> <span class="attribution"><span class="source">Gunz et al. (2020) / Science Advances. </span>, <span class="license">Author provided</span></span></figcaption></figure><p>Within our extended primate family consisting of lemurs, monkeys, and apes, humans have the largest brains. Our closest living relatives, chimpanzees, weigh about two-thirds as much as us, yet our brains are about 3.5 times larger.</p>
<p>Ours are also organised differently, and take longer to grow and mature. This extended period of development leads to a particularly long childhood for humans – one that requires extra parental care and protection. </p>
<p>Brains consume a large amount of energy. For a species that has a small brain at birth and a large one in adulthood, growth must either occur rapidly, or over a long time, or through a combination of both.</p>
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Read more:
<a href="https://theconversation.com/how-smart-were-our-ancestors-turns-out-the-answer-isnt-in-brain-size-but-blood-flow-130387">How smart were our ancestors? Turns out the answer isn't in brain size, but blood flow</a>
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<p>Researchers first observed exceptionally large brains in the human fossil record from about 300,000 years ago. However, the slower rate of brain development, which is now unique to humans, began more than three million years ago in the australopithecine lineage. These two-footed hominins from Africa are thought to be ancestral to our genus, <em>Homo</em>. </p>
<p>What triggered the evolutionary brain expansion in hominins, and how this relates to human behaviour, remain hotly debated topics among palaeoanthropologists.</p>
<h2>The Dikika child</h2>
<p>In 2000, an Ethiopian team uncovered an astonishing find in the country’s Dikika region: the skeleton of an ancient baby with a nearly complete skull. </p>
<p>Dated to about 3.3 million years ago, this youngster belonged to the same genus and species as the iconic australopithecine adult female <a href="https://en.wikipedia.org/wiki/Lucy_(Australopithecus)">Lucy</a> – <em>Australopithecus afarensis</em>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/324494/original/file-20200401-66115-1kr2msc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Australopithecine skeleton (left) and reconstructions of australopithecines Lucy and the Dikika child.</span>
<span class="attribution"><span class="source">Institute of Human Origins & Zeray Alemseged</span></span>
</figcaption>
</figure>
<p>In a <a href="https://advances.sciencemag.org/content/6/14/eaaz4729">new paper</a> published in Science Advances, we reveal that Lucy’s species shows surprising similarities and differences with both chimpanzees <em>and</em> humans. But in order to make these comparisons, we first needed to work out two critical details: </p>
<ol>
<li>exactly how old was the Dikika child when it died? </li>
<li>how did its brain size compare to adult members of its species, such as Lucy?</li>
</ol>
<h2>X-rays to the rescue</h2>
<p>Brains do not fossilise, but as they grow and expand during childhood, the tissues surrounding them leave their mark inside the skull. </p>
<p>Using three-dimensional virtual models, researchers can measure the space within the brain case as a proxy for brain size. This is accomplished through computed tomography (CT), or synchrotron X-ray imaging. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/fKhnaDmVJ98?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This 3D animation shows the skull of the Dikika child.</span></figcaption>
</figure>
<p>A <a href="https://www.esrf.eu/about/synchrotron-science/synchrotron">synchrotron</a> is a machine that accelerates electrons close to the speed of light and directs them around a large ring. By forcing electrons to travel in a circular direction with magnetic fields, extremely bright light is produced that can be filtered and adjusted for research purposes. </p>
<p>A benefit of this approach is that permanent impressions of brain folds on the bone can provide clues about key aspects of the brain’s organisation. Synchrotron imaging can also provide powerful insights into dental development.</p>
<h2>The truth is in the tooth</h2>
<p>A seldom recognised fact about humans and other primates is that our milk (baby) teeth and first molars are marked with a <a href="https://thereader.mitpress.mit.edu/birth-certificate-neonatal-lines/">line formed at birth</a>. Similar to the growth rings of a tree, cross sections of teeth also reveal daily growth lines reflecting the body’s internal rhythms during childhood. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/the-lengthy-childhood-of-endangered-orangutans-is-written-in-their-teeth-77564">The lengthy childhood of endangered orangutans is written in their teeth</a>
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<p>Having access to precise records of the Dikika child’s teeth, we were able to determine how old the child was when it died. Our team’s dental experts calculated an age of 861 days, about 2.4 years. </p>
<p>This means the infant grew its molar teeth rapidly – similar to chimpanzees, and faster than humans. Surprisingly, however, its rate of brain development seemed to have shifted from the fast lane to the slow lane.</p>
<h2>Extending brain growth</h2>
<p>Virtual models of australopithecine brain cases reveal members of Lucy’s species had a chimpanzee-like brain organisation, but grew for a longer period of time.</p>
<p>Our estimates suggest that by 2.4 years old, australopithecine children had brains that were only about 70% as big as adults, while average chimpanzees of the same age would have completed more than 85% of their brain growth. Thus, this species may bridge the gap between the long childhoods humans enjoy today, and the shorter ones of our ape-like ancestors.</p>
<p>Among primates in general, different rates of growth and maturation are associated with varied strategies of caring for infants. Slowing brain development is a way to spread the energetic needs of highly dependent offspring over many years. And this can be linked to a long reliance on caregivers. </p>
<p>Lengthening the period of brain growth also stretches out a species’ highly impressionable learning period. Extended brain growth in Lucy’s species may have provided a basis for the subsequent evolution of the brain and social behaviour in our ancestors. </p>
<p>These baby steps would have been critical for the long childhood that is now often regarded as a keystone of human uniqueness.</p>
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Read more:
<a href="https://theconversation.com/what-teeth-can-tell-about-the-lives-and-environments-of-ancient-humans-and-neanderthals-104923">What teeth can tell about the lives and environments of ancient humans and Neanderthals</a>
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<img src="https://counter.theconversation.com/content/130535/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tanya M. Smith receives funding from the Australian Academy of Science and the US National Science Foundation. </span></em></p><p class="fine-print"><em><span>Philipp Gunz receives funding from the Max Planck Society (Germany).</span></em></p><p class="fine-print"><em><span>Zeray Alemseged receives funding from University of Chicago. </span></em></p>Our findings reveal the slowing down of brain development in our ape-like ancestors began more than three million years ago.Tanya M. Smith, Professor in the Australian Research Centre for Human Evolution, Griffith UniversityPhilipp Gunz, Group Leader, Max Planck Institute for Evolutionary AnthropologyZeray Alemseged, Professor, University of ChicagoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1344102020-03-31T14:07:14Z2020-03-31T14:07:14ZFossil track sites tell the story of ancient crocodiles in southern Africa<figure><img src="https://images.theconversation.com/files/322555/original/file-20200324-155658-1qeto17.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Reptile, avian and mammal tracks and Middle Stone Age artefacts on a large track bearing surface which has since been buried by a landslide.</span> <span class="attribution"><span class="source">Images modified from Helm, et al. 2020. South African Journal of Science, 116</span></span></figcaption></figure><p>“<a href="https://www.livescience.com/40311-pleistocene-epoch.html">The Pleistocene</a>” often evokes images of ice ages – with much of the planet covered by great ice sheets. <a href="https://doi.org/10.1016/j.quascirev.2017.12.002">In reality</a>, this geological epoch that started 2.6 million years ago and lasted until about 11,700 years ago was a time of wildly swinging climatic conditions, typically with long, cold “glacial” phases interspersed with warm “interglacials”. </p>
<p>On the Cape south coast of South Africa, the effects of these changes were dramatic. Sea levels dropped during the “glacials”, exposing the vast Palaeo-Agulhas Plain, and around 91,000 years ago the coastline was as much as <a href="https://asu.pure.elsevier.com/en/publications/middle-and-late-pleistocene-paleoscape-modeling-along-the-souther">60 km south of its present location</a>. In contrast, during an “interglacial” around 400,000 years ago, sea levels were as much as <a href="https://doi.org/10.1016/j.epsl.2012.09.006">13 metres above</a> their present levels. Extensive traditional palaeontological evidence from this region, in the form of body fossils, indicates the existence of a Pleistocene megafauna, some members of which are now extinct.</p>
<p>However, it is becoming evident that this “body fossil record” is not complete. Ichnology – the study of tracks and traces – can complement this record. Fossil tracksites have proven their capacity to teach us the unexpected.</p>
<p>Today the Cape south coast of South Africa contains numerous palaeosurfaces. These rock surfaces are the cemented remains of the dune and beach surfaces that existed when vertebrates, including our <em>Homo sapiens</em> ancestors, were making tracks in the region in the Pleistocene Epoch.</p>
<p>Our research team at the African Centre for Coastal Palaeoscience at Nelson Mandela University has been able to identify <a href="https://doi.org/10.1016/j.quascirev.2019.07.039">more than 250 vertebrate tracksites</a> along a 350kms stretch of the Cape south coast. Together these sites contribute to an ecological census of the diverse fauna that inhabited the coast, and they help in the interpretation of palaeoenvironment. For example, the presence in the region of <a href="http://dx.doi.org/10.17159/sajs.2018/20170266">giraffe</a> and <a href="https://www.cambridge.org/core/journals/quaternary-research/article/new-fossil-sea-turtle-trackway-morphotypes-from-the-pleistocene-of-south-africa-highlight-role-of-ichnology-in-turtle-paleobiology/61B73C3B8C5812C3CB6731636C568BBD">hatchling turtles</a> is only known through our documentation of their trackways. And the early modern human presence is represented not only <a href="https://www.nature.com/articles/s41598-018-22059-5">by tracks</a> but also by <a href="https://doi.org/10.1016/j.pgeola.2019.08.004">evidence of patterns</a> that our ancestors created on surfaces of sand.</p>
<p>Now we can add crocodiles to the list of ancient animals that populated this area during the Pleistocene Epoch. In <a href="https://doi.org/10.17159/sajs.2020/6542">a paper</a> <a href="https://www.sajs.co.za/article/view/6542">published</a> in the South African Journal of Science, our team described the tracks and probable swim traces of large reptiles from this coast, from a series of sites within the Garden Route National Park. Swim traces are the traces that a swimming animal makes on the bottom surface of a body of water. Their appearance varies, depending on the water depth and the length of the animal’s limbs; for example, in deep water only faint scrapes may be present where its claws or digits just touch the bottom. </p>
<p>While crocodylian fossil swim traces have been <a href="https://www.researchgate.net/publication/258860622_The_fossil_record_of_crocodylian_tracks_and_traces_an_overview">described from other continents</a>, to the best of our knowledge the examples we describe are the first such reptilian swim traces from Africa. One example of <a href="http://dx.doi.org/10.1016/j.palaeo.2014.04.021">hippopotamus swim traces</a> has been reported from Kenya.</p>
<p>Among other benefits, understanding these palaeoenvironments and palaeoclimates (which are relatively recent in ‘geological time’) may help us to better understand our current challenges with climate change.</p>
<h2>When large reptiles roamed</h2>
<p>Our findings suggest, based on the composition of the rock surfaces, that the tracks and swim traces were made in a lagoon setting. The likelihood is that tracks of both the Nile crocodile (<em>Crocodylus niloticus</em>) and the Water Monitor (<em>Varanus niloticus</em>) are present. </p>
<p>There are no reptiles in the region today that are capable of making such tracks and traces, and there is nothing substantial to suggest their presence on the Cape south coast from the archaeological record or historical records. The current southern range limit of the Nile crocodile is from a site many hundreds of kilometres to the northeast, where a population was introduced.</p>
<p>These findings therefore probably indicate that there was once a more extensive range for the Nile Crocodile and the Water Monitor. Given the ectothermic biological requirements of large reptiles, we can infer a warmer climate, probably during a warm “interglacial”. </p>
<p>Embedded in one of the palaeosurfaces, which contained multiple large reptile trackways, as well as mammal and avian tracks, we found two Middle Stone Age stone artefacts, pictured below. We cannot be certain what they were used for, as we were not permitted to remove them for detailed analysis. But their presence suggests something which had not previously been documented: a spatial and temporal association in this environment between humans and large reptiles, or at least mutual use of habitat. Unfortunately a large landslide has subsequently buried this track-bearing surface.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/322628/original/file-20200324-155645-17mmlkm.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Middle Stone Age artefacts, scale bars in cm and mm.</span>
<span class="attribution"><span class="source">Authors supplied</span></span>
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</figure>
<p>Rock samples from these surfaces have been taken for dating. Based on <a href="https://doi.org/10.1016/j.palaeo.2007.08.005">previous</a> <a href="https://doi.org/10.1016/j.quascirev.2010.10.003,">dating studies</a> we anticipate that the results are likely to be within the range of 158,000 years to 70,000 years. Obtaining an accurate date would establish the approximate moment in time when these tracks were registered, and would help to corroborate the Middle Stone Age appearance of the stone artefacts.</p>
<h2>Deeper understanding</h2>
<p>These discoveries illustrate again the potential of ichnology to complement the traditional palaeontology record, and to contribute to the understanding of Pleistocene palaeoenvironments, in an area which is of great importance in the study of modern human origins.</p><img src="https://counter.theconversation.com/content/134410/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Helm 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>While crocodylian fossil swim traces have been described from other continents, to the best of our knowledge the examples we describe are the first such reptilian swim traces from Africa.Charles Helm, Research Associate, African Centre for Coastal Palaeoscience, Nelson Mandela UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1333702020-03-16T13:29:29Z2020-03-16T13:29:29ZA tiny bone from Little Foot’s skeleton adds fresh insights into what our ancestors could do<figure><img src="https://images.theconversation.com/files/319543/original/file-20200310-61060-mzpfk9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Little Foot's skull, with the arrow on the right-hand image indicating the specimen's atlas.</span> <span class="attribution"><span class="source">R.J. Clarke/Author supplied</span></span></figcaption></figure><p>In his book <a href="https://www.goodreads.com/book/show/36475.Wonderful_Life"><em>Wonderful Life</em></a>, Professor Stephen Jay Gould – an evolutionary biologist, palaeontologist and widely-read popular science author – described the evolution of life in the following way: </p>
<blockquote>
<p>Life is a copiously branching bush, continually pruned by the grim reaper of extinction, not a ladder of predictable progress.</p>
</blockquote>
<p>Studying <em><a href="http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-afarensis">Australopithecus</a></em>, an extinct hominin genus that represents a branch of our family tree, is an excellent way to make more sense of our bushy family tree, and understand better how species emerge, evolve and disappear.</p>
<p>We don’t yet know the identity of <em>Homo</em>‘s direct ancestor, but the most likely candidate is probably one of the <em>Australopithecus</em> species that lived in Africa <a href="https://www.maropeng.co.za/content/page/australopithecus">between 4 and 2 million years ago</a>. But it’s difficult to study the biology and history of <em>Australopithecus</em>; the fossil record for the genus is just too fragmentary. </p>
<p>There have been some major and exciting finds along the way. For example, the discovery of a partial <em>Australopithecus</em> – later <a href="https://iho.asu.edu/about/lucys-story">nicknamed Lucy</a> – in Ethiopia in 1974 provided valuable information. But Lucy’s skeleton is only 40% complete and lacks important elements – like a complete skull.</p>
<p>A more complete skeleton, named Little Foot by researchers, offers scientists a chance to fill in the gaps in their knowledge. A number of studies have been done on the skeleton over the past few years. My colleagues and I have added to this body of knowledge in <a href="https://www.nature.com/articles/s41598-020-60837-2">a paper</a> that explores Little Foot’s first cervical vertebra, also called the atlas.</p>
<p>Our paper sheds light on an important part of <em>Australopithecus</em>’s anatomy. It helps us understand better how these ancient hominins lived. The findings suggest that this specimen could climb and move in trees. But it may also have been able to walk on the ground. That echoes the results of <a href="https://www.sciencedirect.com/science/article/pii/S0047248418302343">a previous study</a> we conducted, which focused on Little Foot’s inner ear. The same study also supports the hypothesis of a late emergence of human brain metabolism. </p>
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Read more:
<a href="https://theconversation.com/virtual-images-reveal-secrets-of-an-ancient-fossils-brain-and-inner-ear-108349">Virtual images reveal secrets of an ancient fossil's brain and inner ear</a>
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<p>This sort of research brings us closer to our origins and contributes to a thorough portrait of the main characters in human evolutionary history. It also illustrates Gould’s description of our evolution as a “copiously branching bush”.</p>
<h2>The first cervical vertebra of Little Foot</h2>
<p>The first skeletal elements of Little Foot were unearthed from the Sterkfontein Caves near Johannesburg, South Africa, in 1994 and 1997. The caves are among the richest sites of fossil remains in the world, and form part of what’s known as the <a href="https://www.maropeng.co.za/">Cradle of Humankind</a>.</p>
<p>After 20 years of meticulous excavations by Ron Clarke and his team, Little Foot turned out to be the most complete <em>Australopithecus</em> skeleton ever discovered: it is more than 90% intact. The specimen has been dated to <a href="https://www.nature.com/articles/nature14268">3.67 million years old</a>. </p>
<p>Various anatomical studies have been recently conducted on Little Foot. For instance, <a href="https://www.sciencedirect.com/science/article/pii/S0047248418302793">we’ve virtually replicated</a> the inner surface of the braincase to deliver information about brain size, shape and organisation. We’ve <a href="https://www.sciencedirect.com/science/article/pii/S0047248418302343">also studied the shape of the inner ear</a>, which is part of the balance system. The findings told us more on Little Foot’s brain and behavior. </p>
<p>Little Foot’s first cervical vertebra, or atlas, is nearly intact and represents a key component of <em>Australopithecus’</em> biology because it connects the skull with the rest of the skeleton. It also plays a role in how blood is supplied to the brain via the vertebral arteries. </p>
<p>By studying it we’ve been able to understand more about how <em>Australopithecus</em> moved, specifically their heads and necks, and the blood flow that irrigated their brains. We turned our attention to it in a bid to confirm or contradict previous findings and to find out more about <em>Australopithecus</em>. </p>
<p>The cranial base was filled with sediments. These were physically removed and the skull was scanned using a technique called <a href="https://www.microphotonics.com/what-is-micro-ct-an-introduction/">microtomography</a> at the University of the Witwatersrand, in South Africa. This imaging technique is far more accurate than the classical medical imaging tools and provided us with high-resolution images of the vertebra that could be virtually extracted from the sediments.</p>
<h2>Key findings</h2>
<p>Our main findings centred on Little Foot’s locomotion – the way it moved; the way this evolved over time; and, its brain metabolism.</p>
<p>First, what we discovered about Little Foot’s head and neck movements indicates that this specimen could climb and move in trees, but this does not exclude the possibility that it may also have walked on the ground. This finding is in accordance with results from our previous study <a href="https://theconversation.com/virtual-images-reveal-secrets-of-an-ancient-fossils-brain-and-inner-ear-108349">about Little Foot’s inner ear</a>.</p>
<p>Second, we compared the anatomy of Little Foot’s vertebra to two other <em>Australopithecus</em> specimens. One came from the same site as Little Foot, but from a different geological unit that is younger. The second specimen was found in the 1970s in Hadar, Ethiopia – the same site where Lucy was discovered.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=588&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=588&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=588&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=739&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=739&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320424/original/file-20200313-115073-1gmo1is.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=739&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A comparative table of the three atlases found in the localities where three iconic <em>Australopithecus</em> specimens were found.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
</figcaption>
</figure>
<p>The atlas of Little Foot is similar to the one of the <em>Australopithecus</em> specimen from Ethiopia. The additional specimen from South Africa, which comes from the geologically younger deposits of Sterkfontein, is more human-like. These observations could indicate that at least some earlier species of <em>Australopithecus</em> may have spent much more time in trees than the later representatives of the genus.</p>
<p>Finally, our estimation of blood flow supplying Little Foot’s brain shows that the energetic costs of <em>Australopithecus’</em> brain were lower than those estimated in modern humans. This could be due to <em>Australopithecus’</em> relatively small brain, a diet that incorporated less meat (and so provided less energy), or because other organs required more energy.</p>
<p>This confirms the late emergence of the human-like brain metabolism that <a href="https://theconversation.com/how-smart-were-our-ancestors-turns-out-the-answer-isnt-in-brain-size-but-blood-flow-130387">previous studies</a> suggested.</p>
<h2>More to come</h2>
<p>There is still more work to be done on Little Foot’s skeleton – we are planning more studies using the various tools offered by “virtual paleoanthropology”. These studies and others will help us to shed more light on a crucial part of human ancestory’s family tree.</p><img src="https://counter.theconversation.com/content/133370/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Amélie Beaudet received funding from the Centre of Excellence in Palaeosciences, Claude Leon Foundation, French Institute in South Africa, Palaeontological Scientific Trust, South African National Research Foundation and University of the Witwatersrand. </span></em></p>The findings suggest that this specimen could climb and move in trees. But it may also have been able to walk on the ground. This echoes previous studies.Amélie Beaudet, Postdoctoral fellow, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1321012020-02-25T19:00:26Z2020-02-25T19:00:26ZStone tools show humans in India survived the cataclysmic Toba eruption 74,000 years ago<figure><img src="https://images.theconversation.com/files/317004/original/file-20200225-24668-1t3hkj5.JPG?ixlib=rb-1.1.0&rect=3%2C6%2C2281%2C1702&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Christina Neudorf</span>, <span class="license">Author provided</span></span></figcaption></figure><p>About 74,000 years ago a volcanic eruption at what is now Lake Toba in Sumatra, Indonesia, created one of the most dramatic natural disasters of the past 2 million years. The plume of the eruption punched 30 kilometres or more into the sky, eventually blanketing much of India and parts of Africa in a <a href="https://pubs.geoscienceworld.org/gsa/geology/article-abstract/15/10/913/204210/Dispersal-of-ash-in-the-great-Toba-eruption-75-ka">layer of ash</a>.</p>
<p>Some scientists <a href="https://www.cambridge.org/core/journals/quaternary-research/article/climatevolcanism-feedback-and-the-toba-eruption-of-74000-years-ago/6C5611CF710962C41436E08196EFE9E6">argue</a> the eruption plunged Earth into a six-year “volcanic winter” followed by a thousand-year cooling of the planet’s surface. The long chill, the argument goes, may have resulted in the near extinction of our own species. </p>
<p>One <a href="https://www.sciencedirect.com/science/article/abs/pii/S0047248498902196">prominent theory</a> says the eruption was a key event in human evolution. If this is right, the few human survivors in Africa would have developed more sophisticated social, symbolic and economic strategies to cope with the harsh conditions. These new strategies might then have enabled them to repopulate Africa and migrate into Europe, Asia and Australia by 60-50,000 years ago. </p>
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Read more:
<a href="https://theconversation.com/armageddon-and-its-aftermath-dating-the-toba-super-eruption-10393">Armageddon and its aftermath: dating the Toba super-eruption</a>
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<p>It is still unclear how intense the fallout from the Toba eruption really was, and how it affected humans. The debate has been running for decades, drawing on evidence from climate science, geology, archaeology and genetics.</p>
<p>We have found new evidence that humans in India survived the Toba eruption and continued to flourish after it. The study – by researchers from the University of Queensland, the University of Wollongong, the Max Planck Institute for the Science of Human History, the University of Allahabad and others – is <a href="https://www.nature.com/articles/s41467-020-14668-4">published in Nature Communications</a> today.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=532&fit=crop&dpr=1 600w, https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=532&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=532&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=668&fit=crop&dpr=1 754w, https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=668&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/317006/original/file-20200225-24690-1of22zq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=668&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">Some of the stone tools found at Dhaba.</span>
<span class="attribution"><span class="source">Chris Clarkson</span></span>
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</figure>
<h2>Living through the eruption</h2>
<p>We studied a unique archaeological record that covers 80,000 years at the Dhaba site in the middle Son valley of northern India. Ash from the Toba eruption was found in the Son valley back in the 1980s, but until now there was no archaeological evidence to go with it. </p>
<p>The Dhaba site fills a major time gap in our understanding of how ancient humans survived and migrated out of Africa and across the world. The stone tools we found at Dhaba are similar to the ones people were using in Africa at the same time. </p>
<p>These toolkits were present at Dhaba before and after the Toba super-eruption, indicating that populations survived the event. It is likely that humans made the same kinds of tools all along the dispersal route from Africa through India, reaching Australia by <a href="https://www.nature.com/articles/doi:10.1038/nature22968">at least 65,000 years ago</a>.</p>
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Read more:
<a href="https://theconversation.com/buried-tools-and-pigments-tell-a-new-history-of-humans-in-australia-for-65-000-years-81021">Buried tools and pigments tell a new history of humans in Australia for 65,000 years</a>
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<p>Dhaba therefore provides a crucial cultural link between Africa, Asia and Australia. Although fossil and genetic evidence indicate modern humans have lived outside Africa for the past 200,000 years (at sites such as Apedima, Misliya,
Qafzeh, Skhul, Al Wusta and Fuyan cave) only human fossil evidence can prove beyond doubt they were in India 80,000 years ago. </p>
<p>Nevertheless, the stone tools at Dhaba go a long way toward demonstrating human presence.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=371&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=371&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=371&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=467&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=467&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316996/original/file-20200225-24668-k6jcdh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=467&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Possible routes of ancient human migration.</span>
<span class="attribution"><span class="source">Chris Clarkson</span>, <span class="license">Author provided</span></span>
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<h2>Putting together the puzzle</h2>
<p>Our findings at Dhaba fit with archaeological evidence from Africa, Asia, and elsewhere in India to support the idea that the Toba super-eruption had minimal effects on humans and did not cause a population bottleneck. Archaeological sites in southern Africa show human populations thrived following the Toba super-eruption. </p>
<p>Climate and vegetation records from Lake Malawi in East Africa likewise show <a href="https://www.pnas.org/content/early/2013/04/24/1301474110.abstract">no evidence</a> for a volcanic winter at the time of the eruption. Genetic studies similarly have not detected a clear population bottleneck around 74,000 years ago. </p>
<p>At Jwalapuram, in southern India, <a href="https://science.sciencemag.org/content/317/5834/114">Michael Petraglia and colleagues</a> found similar Middle Palaeolithic stone tools above and below a thick layer of Toba ash. At the Lida Ajer site in Sumatra, close to the eruption itself, Kira Westaway and colleagues <a href="https://www.nature.com/articles/nature23452">found human teeth</a> dated to 73,000-63,000 years ago. This indicates humans were living in Sumatra, in a closed-canopy rainforest environment not long after the eruption.</p>
<p>Our new findings contribute to a revised understanding of the global impact of the Toba super-eruption. While the Toba super-eruption was certainly a colossal event, global cooling may have been less significant than previously thought. </p>
<p>In any case, archaeological evidence suggests that humans survived and coped with one of the largest volcanic events in human history. Small bands of hunter-gatherers turned out to be highly adaptable in the face of climate change. </p>
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Read more:
<a href="https://theconversation.com/under-the-volcano-predicting-eruptions-and-coping-with-ash-rain-32899">Under the volcano: predicting eruptions and coping with ash rain</a>
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<img src="https://counter.theconversation.com/content/132101/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Clarkson receives funding from the Australian Research Council</span></em></p><p class="fine-print"><em><span>Michael Petraglia 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>An archaeological site in India sheds new light on how ancient humans dispersed from Africa across the world.Chris Clarkson, Professor in Archaeology, The University of QueenslandMichael Petraglia, Professor of Archaeology, Max Planck Institute of GeoanthropologyLicensed as Creative Commons – attribution, no derivatives.