![]() The new genealogy also contains hints of early journeys. ![]() These groups began interbreeding more around 50,000 years ago, but by 20,000 years ago this largely stopped. They carried DNA from three distinct lineages that originated in the distant past, from eastern, central and southern Africa. In line with this, a second study published this week obtained ancient DNA from six sub-Saharan African people who lived within the past 18,000 years. Read more: Human evolution: The astounding new story of the origin of our species “There’s a lot of very deep lineages within Africa, which are suggestive of that notion of there being multiple source populations, very deeply diverged, representing really ancient splits.” “Our findings are certainly perfectly compatible with that,” says McVean. If that is correct, humanity doesn’t have a central origin point. Many anthropologists now think there were multiple populations spread across Africa, which were sometimes separated and sometimes interbred. They were thought to be 197,000 years old, but a paper published in January presented evidence that they are more like 233,000 years old. The next oldest are those from Omo-Kibish in Ethiopia, in the east. The oldest known specimens are from Jebel Irhoud in Morocco, in north Africa, and are perhaps 315,000 years old. sapiens fossils are from the north and east of Africa, but few have been discovered, so we don’t know our species’ early range with any certainty. “I would definitely not take the naive and immediate answer,” says Jennifer Raff at the University of Kansas. The simplistic interpretation of this is that humanity first evolved in that region, but it is likely that subsequent migrations have interfered with the data. Instead, the variants date to the earliest members of our genus, Homo. Those oldest variants are about 2 million years old, so they long predate our species, which emerged around 300,000 years ago. Variants that emerged before 72,000 years ago were most common in north-east Africa, and the oldest 100 variants were also from there, specifically in what is now Sudan. To do this, they also looked at an additional 3589 samples of ancient DNA that weren’t good enough to include in the tree, but did shed light on when the variants emerged. ![]() They identified 6,412,717 variants and tried to figure out when and where each one arose. The team focused on bits of DNA that vary from person to person. “The different data sets have been produced over time, using different technologies, analysed in different ways,” says McVean. Putting them together into a tree was challenging. McVean and his colleagues compiled 3609 complete genomes, almost all of which belonged to our species, Homo sapiens, except for three Neanderthals and one from the Denisovan group, which may be a subspecies of H. Geneticists have been reading people’s entire genomes for the past two decades. New Scientist Live is going hybrid, with a live in-person event in Manchester, UK, that you can also enjoy from the comfort of your own home, from 12 to 14 March 2022. Join us for a mind-blowing festival of ideas and experiences.
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