A new study claims that we gained evolutionary advantages after our ancestors bred with Neanderthals and Denisovans.
During our long evolutionary history, human ancestors have bred with both Neanderthals and Denisovans, slightly less evolved species. While most scientists claim that we have suffered from our ancestors’ promiscuity, a new study claims that we have gained some advantages that enabled the survival of humans outside Africa.
The study, published in the journal Current Biology, claims that specific traits of modern humans like the immune system and the properties of our skin were the result of interbreeding with the more archaic species of humans. The research reference specific genetic traits which are still present in different ethnic groups in varying proportions.
The study lists 126 different places in the human genome where the impact of the genes from Neanderthals and Denisovans are integrated into groups of people around the world. This aspect has endowed humans with the ability to adapt to various environments as our ancestors spread all over the world., according to Joshua Akey, a professor of genome sciences at the University of Washington.
The researchers revealed that non-African individuals have almost 2 percent of their genomes from Neanderthals. The Denisovan inheritance is in the range of about 2 to 4 percent of our genomes.To reach these results, the researchers examined an extensive number of samples. The study included around 500 participants from South and East Asia as well as Europe.
Some samples of DNA saw lower frequencies of archaic genomes than others, at around 5 percent from both species. However, they also discovered specific parts of the genome where the archaic sequence reached a frequency of around 65 percent. The best example put forward by researchers to argue their theory is that of Tibetans which have a genome featuring 5 percent of Denisovan traits. These traits are what helped them better adapt at breathing at high altitudes.
However, the advantages we received from our ancestors who bred with archaic humans do not limit at better breathing. They also involve a more adaptive immune response, enhanced fat storage, liver function and even keratine production, not to mention the different skin pigmentation.
What do you think about this new study? Do you think that we are better off thanks to Neanderthals and Denisovans?
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