Why Does My Dog Curl Up In A Ball When He Sleeps?

Why Does My Dog Curl Up In A Ball When He Sleeps?, Huffington Post, Sept. 9, 2012. It’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? Margaret Gruen, clinical sciences, featured.