Why Do Dogs Curl When They Sleep?

Dogs sleep in all kinds of positions: On their stomachs, on their backs, sprawled out, or curled up. Puppies especially seem to sleep in positions that make them look as if they’ve collapsed in the middle of something, such as a game of tug-o-war, or with their head in the food dish. The average dog’s ability to catch some z’s is nothing short of admirable.

Do these positions have any significance, or is it a case of random comfort? If your dog curls up or spreads out, what does it mean?

First, we should consider the three most typical sleeping postures for dogs. These are:

  •   Curled up
  •   Flat out on their sides
  •   Other, weirder positions, such as upside down or with head hanging off the couch

What is it that dictates these positions? Are they merely a matter of habit, or something more?

Experts have a theory.

Dogs’ Sleeping Habits are Climate-Related

Experts say that the position a dog chooses to sleep in depends mostly on room temperature. Cold dogs curl up to stay warm and warm dogs stretch out to stay cool. When considering how sled dogs sleep in the snow, this theory seems right on the mark. It’s rare to see a Husky sprawled out on their side in cold weather. Sleeping curled up tight is one way a dog can maintain his body temperature.

Dogs like Huskies, with their thick double coats, handle a colder climate better than some other breeds. Most dogs, in the cold, will curl up into the smallest area possible. The hairs on their back, neck and spine will stand up. The term for this is, “piloerection,” and it’s similar to goosebumps in humans. When dogs curl up in the cold they often cover their nose with their tails, effectively heating the air they breathe. Dogs hold a lot of heat in their paw pads, due to an abundance of blood vessels. They also perspire through their pads. In cold weather, pads can act as a type of heating element, hence the tendency to curl feet up close.

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Am bagel. Not dog. No need to wake.

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Dogs Adjust to the Lifestyle Presented to Them

Most people, thankfully, don’t expect their dogs to live outdoors in the freezing cold. However, because dogs have evolved over centuries of selective breeding, it’s not unusual to see an indoor pampered pooch curled up on the couch exactly like an Iditarod champion. Dogs have amazing resilience. When given a small space, most dogs will simply adapt to it. If you present your dog with a small house with limited space, the dog will adapt to his situation. They might make a few circles, the age-old Wild Dog method purported to “trample down the grass” (really they’re probably just getting comfortable, as you might do when fluffing your pillows) and then with a flop and a groan, they’re down for the count.

Some of heat-seeking breeds, such as Chihuahuas and hairless Chinese Crested, will curl up no matter how warm it seems to be. Some of these dogs will burrow under the blankets, and still curl up with their owners, happy to indulge in temperatures that would drive a double-coated dog out for a drink of water. Part of this is not only because the breed enjoys the warmth, but because it offers a cozy bonding time with the owner.

No matter what the reason may be for dogs to curl up, sleeping time is a quiet time and offers a great opportunity to get close to their owners, to conserve energy for the dog-owner partnership, be it walks in the park or running in the snow.