{"id":136571,"date":"2024-12-13T13:17:48","date_gmt":"2024-12-13T06:17:48","guid":{"rendered":"https:\/\/hotvideos24.online\/?p=136571"},"modified":"2024-12-13T13:17:48","modified_gmt":"2024-12-13T06:17:48","slug":"a-new-timeline-of-when-neanderthals-and-ancient-humans-interbred","status":"publish","type":"post","link":"https:\/\/hotvideos24.online\/?p=136571","title":{"rendered":"A new timeline of when Neanderthals and ancient humans interbred"},"content":{"rendered":"<p> <script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<\/p>\n<div>\n<div class=\"summary-box\" data-testid=\"summary-box\">\n<div class=\"summary-box__content\">\n<h2 class=\"summary-box__headline\">The Summary<\/h2>\n<ul class=\"summary-box__items\">\n<li>Many people have a tiny slice of Neanderthal DNA, evidence of interbreeding between the species and ancient human ancestors.<\/li>\n<li>Two new studies suggest that interbreeding occurred during a limited period of time as ancient humans left Africa.<\/li>\n<li>Clarifying that timeline narrows the possible range of time when humans spread to new continents. <\/li>\n<\/ul>\n<\/div>\n<\/div>\n<p class=\"\">Hidden in many people\u2019s genetic codes is a mystery that has long intrigued scientists \u2014 a tiny slice of Neanderthal DNA that persists tens of thousands of years after the species vanished.\u00a0<\/p>\n<p class=\"\">Most non-African people can attribute around 1% to 2% of their DNA to Neanderthal ancestors.<\/p>\n<p class=\"\">But the details of that evolutionary history\u00a0have remained unclear. How often did ancient humans and Neanderthals interbreed? Exactly when did that happen? Why did Neanderthals go extinct, and why did modern humans survive? What does that Neanderthal DNA do for us now?\u00a0<\/p>\n<p class=\"\">Two research groups have separately analyzed collections of ancient genomes and come to the same conclusions about some of those core questions. Studies published <a href=\"https:\/\/www.nature.com\/articles\/s41586-024-08420-x\" target=\"_blank\" rel=\"noopener\">in the journals Nature<\/a> and <a href=\"https:\/\/www.science.org\/doi\/10.1126\/science.adq3010\" target=\"_blank\" rel=\"noopener\">Science on Thursday<\/a> suggest that ancient humans and Neanderthals interbred during a limited period of time as the humans left Africa and migrated to new continents.\u00a0<\/p>\n<p class=\"\">The wave of interbreeding took place roughly 43,500 to 50,500 years ago, according to the findings. Then, over the next 100 generations, most Neanderthal DNA got weeded out \u2014\u00a0but not all. Today, the DNA that remains is linked to traits like skin pigmentation, immune response and metabolism.\u00a0<\/p>\n<p class=\"\">According to the new findings, the interbreeding event happened more recently than some previous estimates suggested, which in turn shifts and narrows the possible range of time when humans spread to places like present-day China and Australia.\u00a0<\/p>\n<p class=\"\">It also clarifies the significance of fossilized remains of humans discovered outside of Africa, like in Europe, that date back more than 50,000 years. The new studies say those populations died off and became evolutionary dead ends.\u00a0<\/p>\n<p class=\"\">\u201cHuman history is not just a story of success. We actually went extinct several times,\u201d said an author of the Nature paper, Johannes Krause, a professor at the Max Planck Institute for Evolutionary Anthropology in Germany. \u201cThere\u2019s multiple lineages that we have identified now that did not contribute to later people.\u201d\u00a0<\/p>\n<p class=\"\">The findings also demonstrate how skilled anthropologists have become at reconstructing ancient DNA and analyzing it to make inferences about the course of human history.<\/p>\n<p class=\"\">\u201cIt\u2019s just very cool that we can look at these events from the past and really reconstruct what our paths look like,\u201d said an author of the Science paper, Priya Moorjani, an assistant professor of molecular and cell biology at the University of California, Berkeley. \u201cFifty thousand years ago is a long time ago, but to be able to have genetic data from these samples really helps us paint a picture in more and more detail.\u201d\u00a0<\/p>\n<p class=\"\">The two research groups took different approaches to their work.\u00a0<\/p>\n<p class=\"\">Moorjani\u2019s group built a catalog of genomic information from 59 ancient individuals \u2014 who lived between 2,000 years ago and 45,000 years ago \u2014 and 275 present-day people. Then the researchers analyzed changes over time in the distribution and length of Neanderthal DNA in those genomes.\u00a0<\/p>\n<p class=\"\">They determined that the flow of Neanderthal genes into humans occurred roughly 47,000 years ago and lasted no more than 7,000 years. Those findings line up with archaeological evidence that suggests Neanderthals and humans overlapped in geography as humans traveled out of Africa. Many scientists suspect the two species crossed paths in the Middle East, but that\u2019s not confirmed.\u00a0\u00a0<\/p>\n<p class=\"\">After the interbreeding, natural selection kept a few traits from Neanderthals while ditching many more.\u00a0<\/p>\n<p class=\"\">\u201cThe majority of selection, positive and negative, on Neanderthal ancestry happened very quickly after the gene flow, within roughly 100 generations,\u201d said a co-author of the Science paper, Leonardo Iasi, a postdoctoral researcher in the evolutionary genetics department at the Max Planck Institute for Evolutionary Anthropology.\u00a0<\/p>\n<p class=\"\">The other new study, in Nature, relied on an analysis of six genomes from remains discovered in Ranis, <a href=\"https:\/\/www.nbcnews.com\/science\/science-news\/45000-year-old-pit-bones-reveals-earliest-human-ancestors-rcna136265\" target=\"_blank\" rel=\"noopener\">a cave site in present-day Germany that sits below a medieval castle<\/a>. The remains date back about 45,000 years, and the DNA suggests two of the six individuals were a mother and daughter.\u00a0<\/p>\n<p class=\"\">\u201cThey\u2019re now the oldest nuclear genomes that we have of modern humans,\u201d Krause said.\u00a0<\/p>\n<figure class=\"styles_inlineImage__yAWZ0 styles_medium__OMa6x\"><picture class=\"styles_image__1qciH\" data-testid=\"picture\"><source media=\"(min-width: 1000px)\" srcset=\"https:\/\/media-cldnry.s-nbcnews.com\/image\/upload\/t_fit-560w,f_avif,q_auto:eco,dpr_2\/rockcms\/2024-12\/241212-caves-ch-1156-d23c5b.jpg 2x, https:\/\/media-cldnry.s-nbcnews.com\/image\/upload\/t_fit-560w,f_auto,q_auto:best\/rockcms\/2024-12\/241212-caves-ch-1156-d23c5b.jpg 1x\"\/><source media=\"(min-width: 320px)\" srcset=\"https:\/\/media-cldnry.s-nbcnews.com\/image\/upload\/t_fit-760w,f_avif,q_auto:eco,dpr_2\/rockcms\/2024-12\/241212-caves-ch-1156-d23c5b.jpg 2x, https:\/\/media-cldnry.s-nbcnews.com\/image\/upload\/t_fit-760w,f_auto,q_auto:best\/rockcms\/2024-12\/241212-caves-ch-1156-d23c5b.jpg 1x\"\/><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/media-cldnry.s-nbcnews.com\/image\/upload\/t_fit-760w,f_auto,q_auto:best\/rockcms\/2024-12\/241212-caves-ch-1156-d23c5b.jpg\" alt=\"D\u00f3me of the Kon\u011bprusy caves.\" height=\"1667\" width=\"2500\"\/><\/picture><figcaption class=\"caption styles_caption__Pe5JC\" data-testid=\"caption\"><span class=\"caption__container\" data-testid=\"caption__container\">The Kon\u011bprusy caves in Czechia, where the Zlat\u00fd k\u016f\u0148 skull was discovered.<\/span><span class=\"caption__source\" data-testid=\"caption__source\">Martin Frouz \/ Anthropology Department of the National Museum in Prague<\/span><\/figcaption><\/figure>\n<p class=\"\">The researchers also analyzed the DNA of an individual found in a cave site in present-day Czechia, about 140 miles from Ranis. The two sites date back to roughly the same period. The results indicated that two of the individuals found in Ranis were closely related to the one in the Czechia cave \u2014 within five or six degrees in family relation.<\/p>\n<p class=\"\">They concluded that the individuals found at the two sites were most likely part of a small isolated population of perhaps just 200. From a genetic perspective, they didn\u2019t make it \u2014\u00a0the population died out.\u00a0<\/p>\n<p class=\"\">\u201cThey present a genetic lineage that has no descendants \u2014 that actually, later on, got extinct,\u201d Krause said.\u00a0<\/p>\n<p class=\"\">However, those individuals\u2019 DNA shares the same traces of Neanderthal influence as the remains that the other team of researchers analyzed. That strengthens the idea of a single event of \u201cadmixture\u201d \u2014 or interbreeding.\u00a0\u00a0\u00a0<\/p>\n<p class=\"\">\u201cIt\u2019s always nice to have two independent studies that are working with independent data using independent methods that come up with basically the same answer. That engenders a lot of confidence,\u201d said Joshua Akey, a professor at the Lewis-Sigler Institute for Integrative Genomics at Princeton University, who wasn\u2019t part of either research group.<\/p>\n<p class=\"\">Chris Stringer, a professor and research leader on human evolution at the Natural History Museum in London, said pinpointing the interbreeding event helps line up other key parts of the human evolution timeline. The findings constrain \u201cthe timing of the arrival of populations in regions like China and Australasia [Australia, New Zealand and Papua New Guinea] that gave rise to present-day people in those areas to less than 50,000 years ago, because their genomes share the same interbreeding event,\u201d he said.<\/p>\n<p class=\"\">The studies also clarify the time frame in which humans interbred with Denisovans, another extinct species, Stringer added \u2014\u00a0that took place after the introduction of Neanderthal DNA.\u00a0<\/p>\n<p class=\"\">Akey said questions remain, though. It\u2019s not clear how often humans and Neanderthals mated. And there\u2019s more to be learned about the traits humans got from Neanderthal and Denisovan DNA. Plus, there\u2019s the mysterious disappearance of Neanderthals 39,000 years ago.<\/p>\n<p class=\"\">Akey said he thinks mating between humans and Neanderthals might have led to the latter\u2019s vanishing.\u00a0<\/p>\n<p class=\"endmark\">\u201cMy inclination is to think that mating was pretty frequent,\u201d Akey said. \u201cAnd that there was enough mating that it contributed to the disappearance of Neanderthals by incorporating them into human populations. But that\u2019s still speculative.\u201d<\/p>\n<p><br class=\"\"\/><\/div>\n<p><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<br \/><div data-type=\"_mgwidget\" data-widget-id=\"1660802\">\r\n<\/div>\r\n<script>(function(w,q){w[q]=w[q]||[];w[q].push([\"_mgc.load\"])})(window,\"_mgq\");\r\n<\/script>\r\n<br \/>\n<br \/><a href=\"https:\/\/www.nbcnews.com\/science\/science-news\/neanderthals-ancient-humans-interbreeding-timeline-rcna183955\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The Summary Many people have a tiny slice of Neanderthal DNA, evidence of interbreeding between the species and ancient human ancestors. Two new studies suggest that interbreeding occurred during a &hellip; <a href=\"https:\/\/hotvideos24.online\/?p=136571\" class=\"more-link\">Read More<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8628],"tags":[],"class_list":["post-136571","post","type-post","status-publish","format-standard","hentry","category-science","entry"],"_links":{"self":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/136571","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=136571"}],"version-history":[{"count":0,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/136571\/revisions"}],"wp:attachment":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=136571"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=136571"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=136571"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}