ThinkstockIt's nighttime and your pup nestles snugly in his bed, rolled up tight like a drum.
It's a common slumber position for dogs, but why? Wouldn't it be more comfortable to stretch out while catching some shut-eye?
SEE ALSO: Should Dogs and Cats Sleep in Your Bed?
Well, yes, says Dr. Margaret Gruen, DVM, a clinician at NC State University College of Veterinary Medicine Animal Behavior Service.
But there are two valid reasons why your canine rolls up in a ball to snooze - and they both relate to evolution.Keeping Cozy
"When dogs sleep in the wild, especially where it's cold, they'll dig a nest and curl up into it," Dr. Gruen says. "This gives them warmth - tucking into a ball conserves body heat. It also protects their most vulnerable organs in the abdomen from would-be predators."
So if your pooch sprawls out to nap - instead of curling up - he's either hot or he feels very safe in his environment.
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