Evidence has been piling up for a while that early humans in Europe had children with the Neanderthals who had been living there for probably 500 thousand years before humans arrived. Very few Neanderthal genes are left in humans today, so what difference does it make? A lot, both genetically and philosophically.
First of all, we still aren’t sure what genetic inheritance the Neanderthals left behind among non-African populations, and we’re even less certain about mixtures that probably took place in the Middle East and Asia between Homo sapiens and hominins like the Denisovans. It’s possible that Europeans inherited red hair from Neanderthals. And just this week, a new study in Nature linked Neanderthal genes to fatty acids that show up in the brains and other tissues of Europeans — but not in Asian populations.
Paleolithic Mixing – Did my Neanderthal ancestors give me a predisposition to accumulate certain kinds of fat? Possibly. Though researchers aren’t sure what role these extra fatty acids play in our bodies, one thing is certain. A large group of Homo sapiens have inherited genetic material from a group that was once considered another species.
So the first way that our Neanderthal heritage matters is that it may actually have a bearing on some aspects of our metabolism, our brain function, and more. Second, it reminds us that what at first might seem to be another species was probably just another kind of human. As humans, we tend to think of ourselves as grand exceptions in the animal world — even though we look like our ape cousins, we have table manners and Android devices and can follow the plot on Game of Thrones. Key to this sense of exceptionalism is the idea that no other creatures alive were ever like us. More here Why Does It Matter If Homo sapiens Had Sex With Neanderthals?.