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What about some shut-eye while pulling Santa's sleigh? Reindeer can sleep while eating, study says

By Nicholas Gerbis
Published: Friday, December 22, 2023 - 9:45am
Updated: Friday, December 22, 2023 - 2:39pm

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Person standing in reindeer stalls
Current Biology Furrer et al.
A researcher observes reindeer as part of the study.

Reindeer don’t get much sleep: In a herd, they take turns grabbing short naps; when fearful of predators, one hemisphere of their brain sleeps while the other keeps watch.

Now, a study published in Current Biology shows they can sleep while eating, too.

Whether carb-loading before pulling Santa’s sleigh or just browsing nature’s produce aisle before the long Arctic winter, reindeer get food while the gettin’ is good.

That continual eating should cause a build-up of physical pressure to sleep, followed by a rebound of more, deeper, non-REM sleep.

But a non-invasive EEG study of four Eurasian tundra reindeer shows the animals experience smaller sleep rebounds during summer, and that brain activity related to non-REM sleep dropped during rumination.

In short, reindeer are more rested after chewing their cud.

That adaptation could help them chow down more when food is most abundant.

Close-up on face of reindeer
Leo Rescia
The last thing an Arctic plant sees.

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