Why does my dog sleep in a ball?

Dogs will sleep in curled up, ball-like position for two reasons. First, they do this to conserve body heat. Keeping body parts close together and preventing body heat from escaping will help your dog stay warm. The second reason dogs sleep in a ball is to protect their vital internal organs from any attacks by a predator.

But there are two valid reasons why your canine rolls up in a ball to snooze — and they both relate to evolution.

When dogs sleep in the wild, especially where it’s cold, they’ll dig a nest and curl up into it, . “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.

And creating security-- If a dog is in unfamiliar territory, he will revert back to the instinct-based, curled-up sleep position.

It's a very common sleep position and is a naturally protective position where the dog is least vulnerable.

A Dog might sleep curled up to stay warm.