Why do dogs sniff each other?

When you’re out walking your dog you have undoubtedly noticed that dogs sniff an awful lot. They sniff their surroundings, they sniff the ground where other dogs have left a scent marking, they greet other dogs by sniffing their butt, and other equally undesirable areas.

How many times have you wondered why?

It has long been believed that dogs sniff other dogs scent markings to establish what others dogs patrol in the same area, so it’s believed to be territorial.

It’s also believed that dogs sniff each other as a formal greeting.

Personally I believe that both of these theories are true, but I also believe that there could be more to it than that.

It is thought that a dog will memorise all of the scent marking smells in their territory, basically building up a database in their mind as to what dogs reside in that same territory.

When one dog sniffs another dog, my theory is that they are building up a better profile of the dogs in their territory; basically putting a face to a smell. This could be useful to a dog in the future. It would enable them to tell from a distance and from sight if a dog is known to be a part of the same territory or not.

This may also account for why some dog greetings go well, while others do not. If a dogs scent is not known to the area a territorial dispute might take place.