Why Do Dogs Smell Each Other's Butts?

We often come across dogs sniffing each other’s butts. When we witness this, we often wonder why they do that. But did you know that there is a logical reason why dogs nudge their nose into each other's rear ends?

Dogs are blessed with an incredible sense of smell that is 10,000 to 100,000 times better than humans. Butt-smelling for dogs is as good as a handshake for human beings. Smelling each other’s butts is considered an important ritual that dogs perform while greeting a fellow dog—as pheromones are released through specialised glands at their butts and near the ears. While dogs unfamiliar with each other might not sniff each other’s ears (it might seem threatening), sniffing butts is a non-aggressive way for them to get acquainted with each other.

To understand why dogs sniff each other’s butts, we must understand their sense of smell and communication methods. Let us address some common questions to get a clear idea about this unique behaviour of our furry friends.

Is it true that dogs have an excellent sense of smell?

Just like human beings, dogs also have five sensory organs. They possess five basic neurological senses: smell, sight, taste, touch, and hearing, which are very strong and steady. But when it comes to smell, dogs are superior to humans. They have a very sturdy smelling sense. A dog has a sense of smell nearly 100,000 times more subtle and effective than human beings. This is because a dog's nasal area contains 150 million olfactory receptors, while a human nose has just 5 million. Research proves that dogs use around 30% of their brain mass for the recognition and analysis of smells, while humans use 5%.

A unique organ, called the Jacobson’s organ (or the vomeronasal organ), helps as a subordinate olfactory system used specifically for biological communication. The two different parts of the dog’s smell recognition structure are the nose and Jacobson’s organ. These two work hand in hand to offer subtle sensibilities that neither organ can accomplish alone. When a dog blazes their nostrils, they actually unlock Jacobson’s organ, which, in turn, opens up the nasal cavity to aromatic molecules. This helps them smell effectively.

Do dogs use their sense of smell to connect?

When humans meet, they observe body language, expressions, and the manner of the words spoken to understand and connect. After considering these aspects, they may prefer to shake hands, hug, share a casual oral greeting, or completely overlook each other.

Since dogs can’t verbally interact, shake hands, or hug each other as humans do, they adopt other techniques to evaluate each other and collect information from body language. Dogs usually stride in a circular motion while inspecting the character and attitude of the fellow dog.

Dogs use their powerful sense of smell, along with a visual valuation, to gain important information about a new canine associate. A dog can identify through the smell whether the new acquaintance is male or female, joyful or violent, strong or weak, or friendly or unfriendly. They acquire an overall idea about each other with a smell. After the initial scrutiny, they get a fair idea of whether to get along or not.

How does smelling each other's butts play a vital role in communication?

Every dog possesses a unique smell through which they can quickly determine whether they know each other or haven’t met before. Dogs smell each other’s butts as a form of greeting to acquire important information from the anal excretions.

As the dogs start smelling each other’s butts, they establish the foundation of a canine association. One dog initiates the sniffing while the other partner pauses for their turn. Dogs also have a strong scent recall that helps them identify other dogs they have not encountered for a long time. When dogs get detached from their group for some reason, they use their sense of smell to catch up on things when they meet next. Smelling each other’s butts conveys the necessary information about them as to where the dog strolled, what they consumed, etc.

There is another reason dogs smell each other's butts – they smell rear ends as a comforting mechanism. Carrying out this innate ritual calms them and acts as a stress relief.

Should I let my dog smell another dog's butt?

Dogs are less likely to have a tiff or fight if they get a sufficient amount of time to sniff one another. Sometimes, they get a little excited when they spend time in groups, which can lead to fights and violence. You need to keep an eye on the behaviour and the body language of the dogs. If both dogs are hale and hearty, ready to meet each other, and can be properly monitored, then letting them smell each other’s butts is a must.