Homo Neanderthalis.
They lived for hundreds of thousands of years, principally in what is now Europe. Neanderthals seem to be the result of an early human migration out of Africa that then evolved to Neanderthal. They never expanded their range beyond what is now Southern Europe and Western Asia. They never evolved into anything else. They alone inhabited their territory until modern man, Homo Sapiens, came along on a much later migration out of Africa. From the fossil records we can tell that during the last part of the Neanderthal reign, from about thirty thousand years ago, these two human species co-existed in the same habitat at the same time, for about 10,000 years, but only one species came out alive. Thirty thousand years ago; twenty thousand years ago; tiny blips of time in the history of human evolution. Neanderthals almost lasted long enough for us to know a time when there were two different species of humans living at the same time in our lifetimes!
Early on, in the early 1900s, it was thought that Neanderthals were dumb brutish grunting cavemen thugs. That perception has shifted over the years, research revealing that Neanderthals had social groups, were cooperative ambush hunting forest dwellers, and were in control of fire and cooking. They either copied art from the arriving homo sapiens, or produced it on their own before the invaders arrived. New evidence continues to be discovered, and new analyses made, so our understanding of our earliest ancestors, and those other human species encountered along the way, continues to evolve. Recent discoveries suggest there were a whole series of early human migrations out of, and back to, Africa, complicating existing explanations. Our neat explanations don’t stay neat for very long.
It has been postulated that Homo Sapiens invaded and wiped out Homo Neanderthal, or they outcompeted them for resources with their superior intellect, or maybe Neanderthals never went extinct at all but were just absorbed by the newcomers. But none of those speculations are supported by evidence. We still don’t know why Neanderthals aren’t here anymore.
Much of what we know has been learned since the first genetic sequencing of Neanderthal DNA in 2010. The question had often been asked: “Did Neanderthals and Modern Humans interbreed?” and that question has been the source of much speculation. The DNA sequencing provided the first conclusive evidence that there definitely was interaction between Neanderthals and Modern Humans. Even after all this time, up to 2% of the DNA of Modern Humans has been contributed by Neanderthals.
That also crushes that theory that maybe Neanderthals never really went extinct but were absorbed by the Modern Humans and continue to exist as part of them to this day. If that were the case, there would be a much higher proportion of Neanderthal DNA in Modern Humans and the total amount of Neanderthal DNA would be more complete. For current humans all over the planet, about 1 to 2% of their DNA is from Neanderthals. But different groups of people have different Neanderthal DNA. Altogether, spread out across a whole lot of different people, about 20% of Neanderthal DNA survives today.
Now that we’ve answered the question about how much Neanderthal DNA survives in today’s humans though, that makes me wonder, how much did Modern Humans affect, or infect, Neanderthal? These two species coexisted for 10,000 years. How much Modern Human DNA did the last Neanderthals have? Was it the same 1 or 2% as we have of theirs? And how much did the amount of homo sapiens DNA they absorbed influence what happened to them?
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