Your dog has been outside all afternoon enjoying the lovely fall weather but is now asking to come back inside. So you open the door to let him in, but as he walks past you, your nose wrinkles with the faint whiff of something unpleasant. You know nothing’s gone bad in the refrigerator, and you just put the garbage out, so you check the soles of your shoes. Nope, nothing there either. Okay, you think, just where IS that smell coming from? Guess what…it’s your dog.

So you call him to your side, lean over, and sniff…ewww. He’s either rolled in feces…or possibly a dead squirrel. Disgusting.

Every dog rolls in something really gross at least once in his lifetime. So why do they do it? Take a step back and try to think like a dog. This probably won’t be easy because pet parents–and yours truly is as guilty as the rest–tend to anthropomorphize their CBFs (canine best friends). This means that we attribute human qualities to them. For the most part, this is acceptable, because dogs do exhibit some human-like characteristics, such as certain emotions and feelings just as a human being would. But on the other hand, who do you know that would roll in poop? (Please don’t answer that.)

This is one situation where dogs will be dogs. They don’t attach the same values to smelling pleasant that humans do, so your dog won’t understand why you’re so perturbed. Their sense of smell is hundreds of times more acute than a human’s, and dogs learn a great deal about the world around them by sniffing. They clearly enjoy the sensation, so it may be that some dogs enjoy the pungent odor of a ripe dead squirrel SO MUCH that they literally immerse themselves in it to get the full experience. If they then encounter another dog, they get to share the experience. (It’s like telling a friend about this fabulous restaurant you visited, or a great vacation you took.)

Another possibility is that dogs who roll in gross stuff are trying to disguise their own natural odor. This harkens back to their hunting ancestry, when dinner had to be caught and killed before eaten. It was easier for a predator to sneak up on a potential meal if the prey couldn’t detect the killer’s scent. Although nowadays most domestic dogs do very little hunting and instead enjoy meals prepared and served to them in the comfort of a warm kitchen, the evolutionary instinct still remains.

What can you do to break this nasty habit? Other than keeping your dog’s environment as clean as possible, it’s not likely that you will be able to convince your dog that it’s not good manners to roll in rotten carcasses. The best thing you can do is put a clothespin over your nose and find a good shampoo.