Palaeontology

Neanderthal genes could explain why some people are early birds

By T.K. Randall
December 18, 2023

Image: AI-generated (Bing AI / Dall-E 3) Does the idea of getting up very early in the morning fill you with dread and despair ? Ever wondered how some people seem to be full of energy the second their head leaves the pillow ?

According to a new study, our Neanderthal ancestors might have possessed a gene that made them predisposed to getting up early and then passed this along to modern humans through interbreeding.

Both species lived alongside one another for thousands of years, with the Neanderthals only disappearing relatively recently (around 40,000 years ago).

Today, it is thought that up to 4% of our genome came from the Neanderthals."When the ancestors of modern Eurasians migrated out of Africa and interbred with Eurasian archaic hominins, namely, Neanderthals and Denisovans, DNA of archaic ancestry integrated into the genomes of anatomically modern humans," the study authors wrote.

"This process potentially accelerated adaptation to Eurasian environmental factors, including reduced ultraviolet radiation and increased variation in seasonal dynamics."

The researchers believe that the tendancy for Neanderthals to live at higher altitudes resulted in a change to their internal body clock (or circadian rhythm) that saw them rise earlier in the morning.

"By combining ancient DNA, large-scale genetic studies in modern humans, and artificial intelligence, we discovered substantial genetic differences in the circadian systems of Neanderthals and modern humans," said lead study author John Capra from the University of California, San Francisco.

"Then by analyzing the bits of Neanderthal DNA that remain in modern human genomes we discovered a striking trend: many of them have effects on the control of circadian genes in modern humans and these effects are predominantly in a consistent direction of increasing propensity to be a morning person."

Source: Gizmodo

Tags: Neanderthal