Because Neanderthal alleles are relatively rare, the researchers needed data representing a really large number of people. They found what they were looking for in data representing more than 112,000 participants in the UK Biobank pilot study. The Biobank includes genetic data along with information on many traits related to physical appearance, diet, sun exposure, behavior, and disease.
Earlier studies had suggested that human genes involved in skin and hair biology were strongly influenced by Neanderthal DNA, Kelso says. But it hadn’t been clear how.
“We can now show that it is skin tone, and the ease with which one tans, as well as hair color that are affected,” Kelso says.
The researchers observe multiple different Neanderthal alleles contributing to skin and hair tones. What they found somewhat surprising is that some Neanderthal alleles are associated with lighter skin tones and others with darker skin tones. The same was true for hair color.
“These findings suggest that Neanderthals might have differed in their hair and skin tones, much as people now do” adds Michael Dannemann, first author of the study.
Imagine. Our Neanderthal ancestors showed individual differences in comparatively trivial characteristics, which they then passed on to many of us.
These can’t have been the Ape Man Neanderthals we heard about fifty years ago… Naw, some other dudes.
Kelso notes that the traits influenced by Neanderthal DNA, including skin and hair pigmentation, mood, and sleeping patterns are all linked to sunlight exposure. When modern humans arrived in Eurasia about 100,000 years ago, Neanderthals had already lived there for thousands of years. They were likely well adapted to lower and more variable levels of ultraviolet radiation from the sun than the new human arrivals from Africa were accustomed to. Paper. (paywall) – Dannemann and Kelso. The contribution of Neandertals to phenotypic variation in modern humans. American Journal of Human Genetics, 2017 DOI: 10.1016/j.ajhg.2017.09.010More.
Like we always say, keep digging.
See also: Neanderthal Man: The long-lost relative turns up again, this time with documents
A deep and abiding need for Neanderthals to be stupid. Why?