Top 7 things we discovered about humanity thanks to DNA

When we hear about mysteries solved by DNA, we obviously think first of all of criminal cases and the like. And it is true that it is very practical DNA to reveal that it was Monique who stabbed Bernard 16 years ago at the barbecue at the Duponts. But DNA can solve much older mysteries. Mysteries that date back tens of thousands of years. Mysteries that concern the entire human species. And that’s even classier.

1. West Africans have genes from an unknown species

We had already told you about the other human species that had lived on Earth before or at the same time as thehomo sapiens, such as Neanderthals and Denisovans. These species were discovered thanks to the fossils that we studied. But research on present-day West African populations has shown that people from that region have some of their DNA (2% to 19%) believed to come from another human species that would have lived on Earth but of which no trace has yet been found in the form of a fossil. Homo sapiens would have crossed paths with this other species about 50,000 years ago and would have mixed (if you know what I mean) with it. All that remains is to continue excavations to possibly find the remains of an unknown ancestor, one of these four. That would be cool.

Researchers have found unknown genes in several West African populations. They could be the trace of a “ghost” ancestor about which science knows nothing yet!

Posted by Sciences et Avenir on Wednesday, February 19, 2020

2. Native Americans have Australian and Asian origins

Thanks to DNA, it was possible to prove that Australians shared a common ancestry with the Native Americans of today’s Amazon. But no, Australia’s first humans didn’t swim their way to South America. In fact, a very long time ago (kind of long before Michel Drucker), populations from Australia went up to Asia and mixed with the local populations. Their descendants then arrived in North America on the Pacific coast and then descended to the Amazon. This is why populations of Amazonia today have DNA in common with the aborigines of Australia. It’s been a hell of a trip.

3. Africans have more Neanderthal genes than previously thought

We often tended to say that our ancestors were Africans who migrated to Europe and Asia and mixed with Neanderthals. As a result, it was said that Europeans and Asians had many genes in common with Neanderthals, but not necessarily Africans who remained in Africa. Except that, in recent years, scientists have realized that they had underestimated the number of round trips that our ancestors would have made between Europe, Asia and Africa. As a result, we realized that the current African populations also had Neanderthal genes. Fewer than Europeans and Asians, but still.

4. Tibetans, Filipinos and Papuans have Denisovan genes

Denisova’s man was only discovered in the early 2010s thanks to a phalanx and two teeth found in a Siberian cave. Until recently, we did not know more about this species close to Neanderthal. That was the big mystery. But, in 2019, we were able to study a jaw fragment found at altitude in Tibet in the 1980s and never analyzed since. It was there that we discovered that the Denisovans had managed to show up as far as the Tibetan plateau before mixing with homo sapiens. In parallel, it was also discovered that the inhabitants of the Philippines and Papua have genes in common with the Denisovans (up to 5%), further proof that this mysterious species has spread well in Southeast Asia. We’ll probably learn more in the next few years since it’s all very recent, and it’s very exciting. Finally, as long as we are curious to know who our distant ancestors were. But if you’ve made it this far, I imagine you’re interested.

According to the researchers, the genome of the inhabitants of Papua New Guinea has integrated between 4 and 6% Denisovan DNA, thus testifying to the help that these genes gave to Homo sapiens.

Posted by Pour la Science on Friday, May 17, 2019

5. There’s been evidence that early Europeans and Neanderthals often intermixed

Until very recently, we only knew that we had genes in common with Neanderthals and that there had been mixtures. But, thanks to research in a Bulgarian cave in 2020, it was deduced that these mixtures had been very common. The 45,000-year-old human fragments found in the cave belonged to several individuals whose Neanderthal roots stretched back only 5 or 6 generations. Basically, that meant their great-great-great-grandfather/mother was Neanderthal. And when we talk about the History of humanity, it’s really VERY close, and that probably means that the homo sapiens and the homo neanderthalensis were caught quite often in Europe.

6. Humans have been fighting coronavirus outbreaks for 20,000 years

Viruses can leave a trace in DNA, and it’s what researchers have found humans have been living with coronaviruses for at least 20,000 years. They also assumed that interbreeding with Neanderthals had weakened us a bit against coronaviruses. We might have resisted the Covid better if we hadn’t slept with the cousins.

A study, published at the end of June, traced the genetic modifications linked to coronaviruses in humans. The…

Posted by La Croix on Wednesday, June 30, 2021

7. Hunter-gatherers and farmers once lived together in Europe

Scientists have analyzed the DNA of several skeletons, all between 4,500 and 5,000 years old and found only a few hundred kilometers from each other. They noticed that there were two profiles among the skeletons which resembled that of the hunter-gatherer and that of the farmer. This means that at the same time and in the same place lived both hunter-gatherers and farmers, and therefore that the arrival of agriculture did not suddenly put an end to hunting/gathering as believed. some.


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