Evolution is the change in the heritable characteristics of biological populations over successive generations. Evolutionary processes give increase biodiversity at every level of biological organization, including the levels of species, individual organisms, and molecules.
We once thought that the neanderthals were the only relatives but recent studies show that the Denisovans also interbred with humans.
Modern humans are now the only human lineage left alive but others not only lived alongside modern humans, but also interbred with them, leaving behind DNA in the human genome. But with enough evidence, it has been proven that the mysterious Denisovans are relatives of modern humans. Denisovans also harbor a small amount of especially exotic DNA, probably from breeding with “super-archaic” humans that split from the others over 1 million years ago.
Previous research discovered that while Denisovans shared a common origin with Neanderthals, they were just as genetically distinct from Neanderthals as Neanderthals were from modern humans.
According to researchers, ancestors of Oceanians interbred with a southern group of Denisovans, while the ancestors of East Asians mixed with a northern group.”The implication is that there were at least three instances of modern humans interbreeding with archaic humans — one with Neanderthals and two with Denisovans,” Browning said. “To me, this suggests that modern humans weren’t so very different from Neanderthals and Denisovans. There are signs that intermixing with archaic humans was occurring in Africa, but given the warmer climate, no one has yet found African archaic human fossils with sufficient DNA for sequencing,”