Being a morning person may be due to Neanderthal DNA
What is the opposite of a night owl? According to new research, it is not a morning lark, but a Neanderthal.
“By analyzing the parts of Neanderthal DNA that remain in the modern human genome, we discovered a surprising trend,” said John Capra, assistant professor of epidemiology and biostatistics at the University of California, San Francisco, and lead author of the new study. statement.
“Many of them have effects on the control of circadian genes in modern humans, and these effects are mostly in the consistent direction of increasing the tendency to be a morning person,” he explained.
Before all the late risers start shouting, we should get this straight: This isn’t a sign that our early brothers and sisters are “less evolved” or anything like that — it’s actually an evolutionary advantage.
“When humans evolved in tropical Africa, the average day was 12 hours long,” Mark Maslin, professor of Earth system science at University College London, who was not involved in the study, told The Guardian. “But the further north we go, the days get shorter and shorter in the winter when food is particularly scarce, so it makes sense…to start gathering food as soon as there is any light to work with.”
See, while anatomically modern humans began making their way out of Africa roughly 70,000 years ago, Europe and Asia had already been home to their own brand of ancient hominids—Neanderthals and Denisovans—for more than 400,000 years. That’s enough time for some species to develop genetic specializations, such as increased resistance to certain diseases, for example, or lighter skin color to cope with the relative lack of sunlight in their northern climates.
Once in A wise man With their end-of-species levels of horniness, our Neanderthal ancestors passed these genes on to their offspring — and while many of their ancient genetic variants have been bred over generations, some have remained the same.
The traits we have to thank Neanderthals have been the subject of a lot of research lately: they seem to be the cause of larger noses, for example, as well as a lower pain threshold and increased susceptibility to COVID-19 (thanks for all that, by the way, Great-Grandpa, Grandpa, Grandpa ).
One environmental factor already known to produce evolutionary adaptations in a wide range of species is the pattern and level of exposure to available light. The further north you go, the more variable the light becomes, with winter days seeing no sun at all if you go far enough poleward – this made Neanderthals’ ability to rise at the right time a very useful adaptation for the hemisphere’s newest inhabitants.
“At higher latitudes, it is useful to have a clock that is more flexible and more able to change to suit changing seasonal light levels,” Capra told The Guardian.
“We don’t think being a morning person is actually what’s beneficial,” he said. Rather, we believe it is an indication of a faster operating clock that is more able to adapt to seasonal changes in light levels.
Of course, just being a morning person isn’t proof that you’re particularly Neanderthal, and the genes the team isolated are only a small part of what decides when we wake up. But this discovery deserves further exploration, Capra says, as well as expanding their methods to investigate other ancient features.
“By combining ancient DNA, large-scale genetic studies on modern humans, and artificial intelligence, we have discovered significant genetic differences in the biological systems of Neanderthals and modern humans,” Capra said.
“Our next steps include applying these analyzes to more diverse modern human populations, exploring the effects of the Neanderthal variants we have identified on the circadian clock in model systems, and applying similar analyzes to other potentially adaptive traits.”
The paper was published in the journal Genome and Evolutionary Biology.