Why Do Dogs Sniff Each Other's Butts?

We've all watched it happen, and we've all wondered why. Now it's time to answer that age-old question: Why do dogs sniff each other's butts?

In short: It's their most effective method for a meet and greet. But why do dogs sniff butts specifically, as opposed to the other parts of their fellow canine companions? Let's take a look at this seemingly bizarre behavior.

Why Do Dogs Sniff Each Other's Butts?

"When one dog greets another with a nose in the derriere, (they're) basically getting a brief biography of (their) new friend, written in scent molecules and pheromones," according to an article by Mental Floss. Two pouches — known as anal sacs — produce these scents, which provide information to other dogs about everything from your pet's health and reproductive status, happiness, gender, owner and diet, the article said.

Dogs aren't the only creatures who get to know each other in this up-close-and-personal fashion, though. There are several other species whose anal glands secrete pheromones that communicate their information to others. For example, cats also have active anal glands. According to PetPlace, these glands "produce strong-smelling secretions intended to send chemical signals about that cat's identity to other animals."

But why do dogs sniff butts of pets and not their human pals? Well, this behavior isn't really about the butt, it's about the placement of those active glands. Humans are designed a bit differently, and the keys to our identity aren't located in quite the same places. So while butt sniffing might be more of an animal-to-animal behavior, gland sniffing spans across many of Earth's species.

Are Certain Dogs More Prone to Butt Sniffing?

Little is known about which dogs are more prone to butt sniffing. Butt sniffing is an equally prominent behavior in all breeds. Typically, the behavior transcends gender as well, although research published in the Journal of the International Society for Anthrozoology back in 1992 suggests that in public spaces, male dogs do more butt sniffing than females.

Can I Train My Pet Not to Sniff Other Dogs' Butts?

Butt sniffing is a totally normal dog behavior, and it's truly the best way for two pets to get to know each other. If you have concerns about the way your dog approaches other dogs, though, an experienced behaviorist may be able to help you teach your dog to temper their enthusiasm or aggression and make more calm introductions. You may also want to train your dog to sit and stay when they encounter other dogs and ask those approaching to please respect your dog's space.

You will definitely want to spend quality time training your dog to listen to commands such as sit, stay and come, regardless of if they're an aggressive butt sniffer or more on the shy and gentle side. That way, if your dog meets another pet who isn't comfortable getting sniffed, you can quickly regain control of the situation by giving your dog a simple order.

Your veterinarian or a pet care professional may be able to further advise you on ways to modify your dog's greeting behavior. However, it's unlikely that you'll be able to stop your dog from sniffing other dog's butts altogether.

My Dog Isn't a Butt Sniffer — Should I Worry?

If your dog doesn't sniff butts and you're concerned, schedule time to meet with your vet. It's very possible that your dog just isn't feeling social or, perhaps, prefers people to dogs. Your dog may also be fearful or anxious based on previous negative experiences. However, you'll want to confirm that your dog's sense of smell is intact — especially if this is a sudden change in behavior — and a trip to the vet can ensure everything's in working order.

Why do dogs sniff each other's butts? It's the same reason why you shake hands with your coworkers: to get to know them a little better. So the next time you see it happen, try not to be embarrassed. After all, butt sniffing is simply a sign that you've got a budding socialite on your hands.