In November 2013, researchers discovered an entirely new species of hominin currently strange to modern science. The genome analysis of a finger bone and two teeth found in a Siberian cave suggested there was interbreeding between modern humans, Neanderthals, Denisovans and an unknown archaic population.
The genome from a Neanderthal was also analyzed from the excavation, and the results suggested that interbreeding was common in human evolution and occurred among members of multiple ancient human-like groups in Europe and Asia more than 30,000 years ago. After our direct ancestors expanded out of Africa, they interbred with both Neanderthals and Denisovans contributing to the genetic diversity of many people today.
In July 2014, scientists found that Tibetans were able to adapt to high altitudes thanks to EPAS1, a gene they acquired when their ancestors bred with Denisovans – a mysterious group of prehistoric hominins that went extinct around 45,000 years ago.
In February 2015, researchers in Germany identified a gene that is only present in humans, making human brains three times bigger and complex than other species. The gene, called ARHGAP11B, is found in modern-day humans and our ancient relatives, Neanderthals and Denisovans, but not in chimpanzees.
Scientists believe that ARHGAP11B played a key role in the evolutionary expansion of the human neocortex and that during evolution human genome must have changed in order to trigger such a massive brain growth – from 30 cubic inches in volume around 3.8 million ago to 85 cubic inches when Neanderthals and Denisovans arrived.
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