I recently reviewed Raven’s Choice, a book by Harper Swan, the premise of which is based on the discovery that at some point in time Neanderthal and Homo sapiens commingled and as a result, we all have Neanderthal DNA. I remembered reading about this in passing, and my interest became piqued while reading this book. So I did a little investigation…
Some 200,000 years ago, the ancestors of modern man evolved in East Africa. They spread throughout the rest of the continent and then moved out into eastern Asia and western Europe. By the time modern humans arrived there, some 45,000 to 80,000 years ago, the Neanderthals had already been there for more than 100,000 years and established their own culture. As Homo sapiens journeyed though these regions, they encountered Neanderthals and at least once in a while, they had sex.
Neanderthals were not a hunched over, brutish people, hairy and with dark complexions. More recent have studies have concluded that Neanderthals were fair-skinned and probably with no more facial hair than modern man. They may have communicated by speech, made and used a diverse set of sophisticated tools, controlled fire, lived in shelters, made and wore clothing. They were skilled hunters of large animals and also ate plant foods, and occasionally made symbolic or ornamental objects. There is evidence that Neanderthals deliberately buried their dead and occasionally even marked their graves with offerings, such as flowers. No other primates, and no earlier human species, had ever practiced this sophisticated and symbolic behavior.
Nevertheless, Homo sapiens and Neanderthals did not merge into a single people, and Neanderthal culture and purebred Neanderthals died out 35,000-30,000 years ago. Hypotheses for the manner of their extinction include a failure or inability to adapt to climate change or competitive exclusion by encroaching Homo sapiens. However, there was enough interbreeding that around 2.5 percent of the DNA in Asians and Europeans is Neanderthal.
The skeletal remains of an individual living in northern Italy 40,000-30,000 years ago are now believed to be that of a Homo sapiens/Neanderthal hybrid, according to a paper in PLOS ONE. Genetic analysis was done on the individual’s nuclear and mitochondrial DNA. The nuclear DNA was mainly Homo sapiens, but the DNA of the mitochondria, which is are cell organelles containing DNA transmitted only from the mother, was Neanderthal. It was concluded the individual was the product of a female Neanderthal who had mated with a male Homo sapiens.
Anthropologists have long wondered why, if Neanderthal and Homo sapiens brains were the same size, did Homo sapiens dominate? A functional comparison has revealed it was a matter of allocation: Neanderthal brains focused more on vision and movement, leaving less room for cognition related to social networking. Homo sapiens evolved distinct genes related to cognitive functions, metabolism and the development of cranial features, the collarbone and the rib cage.
So when I’m acting a little primitive (which my children used to accuse me of), I can blame it on my Neanderthal DNA!