Why do dogs circle before lying down?
Dear Straight Dope:
Why do dogs circle before they sit down?
Sometimes, the obvious answer is the correct one. We checked with our friend Doug Yanega the entomologist, on the grounds that dogs have fleas, so he oughta know about dogs. Doug says:
"The trick to understanding any domestic animal 'stereotypical' behavior is to imagine its value in the wild. A wild dog will often sleep in the open, and walking in a circle before you lay down is a good way to tramp down the vegetation a bit to make a more comfortable "bed." It's also possible that dogs, being social, sleep together and circling is a way of marking out territory and making more room--one of those obviously 'hard-wired' things that haven't yet been bred out.
"Other animals have similar behaviors. Cats like to 'knead' the surface they're going to sleep on with their claws, but they stand in place to do this. I'm not positive about rabbits or rodents, but I think they just hunker down and wriggle, from what I recall of my friends' pets. Maybe each type of critter has its own ritual. Heck, people do some pretty stereotypical maneuvers when they're about to bed down, like fluffing the pillow, getting a glass of water, and so forth. At least a dog doesn't insist on being read Green Eggs and Ham."