from The New York Times

Morning Person? You Might Have Neanderthal Genes to Thank.

Hundreds of genetic variants carried by Neanderthals and Denisovans are shared by people who like to get up early.

by Carl Zimmer

Neanderthals were morning people, a new study suggests. And some humans today who like getting up early might credit genes they inherited from their Neanderthal ancestors.

The new study compared DNA in living humans to genetic material retrieved from Neanderthal fossils. It turns out that Neanderthals carried some of the same clock-related genetic variants as do people who report being early risers.

Since the 1990s, studies of Neanderthal DNA have exposed our species’ intertwined history. About 700,000 years ago, our lineages split apart, most likely in Africa. While the ancestors of modern humans largely stayed in Africa, the Neanderthal lineage migrated into Eurasia.

About 400,000 years ago, the population split in two. The hominins who spread west became Neanderthals. Their cousins to the east evolved into a group known as Denisovans.

The two groups lived for hundreds of thousands of years, hunting game and gathering plants, before disappearing from the fossil record about 40,000 years ago. By then, modern humans had expanded out of Africa, sometimes interbreeding with Neanderthals and Denisovans.

And today, fragments of their DNA can be found in most living humans.

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