Let’s not beat around the bush: dogs love butts. Specifically, one another’s butts. Even more specifically, getting their nose up in them for a good sniff. You or your local Dog Walker may have noticed this behaviour at the dog park, where plenty of new dogs abound. But why do dogs sniff butts? Is it because they, er, smell nice? Or is there a more meaningful (and likely) reason?
The act of butt sniffing in dogs is actually rather fascinating. Read on to find out why.
Why do dogs sniff butts?
Unlike a handshake or a polite “Nice to meet you!” dogs prefer to sniff each other’s butts when they’re first introduced. In a nutshell, it’s basically their rather unique way of greeting a new dog.
But there’s a lot more to a butt sniff than a simple “hello”. Every time a dog sniffs something, they’re using their powerful nose to absorb information about their environment, including other dogs. When a dog sniffs another dog’s butt, they’re gleaning a number of useful details about that dog in a single sniffing session.
So, how does this work exactly? Dogs have an incredibly acute olfactory sense that allows them to soak up this knowledge. Depending on the breed of dog, pooches have a sense of smell that’s between 10,000 and 300,000 more superior than ours. The average dog, though, can smell 100,000 better than us humans. As well, dogs use about a third of their brain to process scents, whereas we only use one-twentieth of it.
Once the scent enters the dog’s nose, it hits a nifty thing called the Jacobson’s organ, or vomeronasal organ. This organ has minute openings on the roof of a dog’s mouth and connects straight to the brain via a bunch of nerves.
Note that it’s not only dogs who possess Jacobson’s organs. All lizards and snakes have them, as do cats, mice, elephants, pigs, cows, and a bunch of other mammals. Experts still aren’t sure whether humans are lucky enough to have them, though!
But wait, why do dogs go for the butt?
You might still be wondering, “Why do dogs sniff butts and not another part of the body?” Well, the reason why dogs sniff each other’s butts is all to do with their apocrine glands. Dogs have apocrine glands all over their bodies, but they’re mostly concentrated in their butt. Here, they’re often known as anal glands, anal sacs, or annal succules.
They’re basically two tiny sacs that sit inside a dog’s butt. The anal glands don’t smell particularly nice given their location, but they do produce pheromones. These pheromones are very useful for dogs. They contain every bit of insight they need to know about another dog.
When a dog sniffs another dog’s butt, they use their Jacobson’s organ to process the pheromones emitted by the anal glands and send information up to the brain.
What can a dog learn by sniffing another dog’s butt?
This is where things get really interesting. There’s just so much that dogs can learn about each other, simply by sticking their noses into one another’s behinds.
Here’s what they can find out during a butt-sniffing session with a new dog:
- Whether they’ve met before
- Their gender
- Their age
- Their reproductive status
- How healthy they are
- Their diet
- Their mood
Who knew a dog’s butt could store all of this, and likely more?!
Why do dogs sniff butts on other dogs, but not on humans?
You may have noticed that when your doggo meets a new human, they’re much more likely to go for their crotch over their butt. Sure, this is rather awkward for you and your guest. But to your dog, it’s just their way of greeting and getting to know this new and fascinating person.
You see, we humans have apocrine glands, too – but they’re located in our armpits and crotches. When we’re standing up, our armpits are generally too high up for dogs, so they go for our crotches instead. This is where they can learn a lot about us.
Interestingly, a dog is more likely to sniff a human’s crotch if that human is menstruating, or has recently had a baby. This is because the apocrine glands are emitting more pheromones than usual, and the dog wants to understand why.
Should I be concerned if my dog seems to sniff too much, or doesn’t sniff butts at all?
Butt-sniffing is a very natural, normal behaviour among dogs. It’s usually nothing to worry about. And in most cases, you can let your dog sniff another dog’s butt – especially if both dogs are properly socialised and in good health.
In some cases, though, you may notice your dog getting a little too overzealous or even aggressive with their sniffing. The other dog might not be feeling it, or even retaliating by becoming hostile. This is where training can come in handy. Teaching your pup easy dog tricks and commands like sit, come, heel, and stay lets you take control if your doggo’s sniffing gets a bit out of hand.
But what if your dog prefers to steer clear of others’ behinds?
It could just be that your pooch prefers human company over dog company. They may not be particularly interested in getting to know other dogs. Or, if it’s just a one-off, perhaps they’re just not feeling very social that day.
Alternatively, they might have had a bad experience in the past and be suffering anxiety around other dogs. If your dog is older, they could be losing their powerful ability to smell.
If you’re ever concerned, you can take your dog to the vet for a check-up. Your vet can assess your pupper’s sense of smell to ensure everything is operating as it should.
