top of page

Scent is important for a dog's understanding of the world, even their self-understanding

Understanding the “self” and “others” is something we as humans comprehend easily – but can dogs? Researchers set out to determine if dogs could understand their inner “selves” through smelling their urine, the urine of another dog, and a modified sample of their own urine. I know, it seems weird! But scent is a very important sense for dogs – it is their primary sensory modality, like sight is for humans. Dogs don’t see themselves in the mirror every day, but they smell their familiar scent constantly. The researchers discussed how dogs do seem to have an understanding of the “self”, because they spent significantly less time smelling the familiar odor of their own pee. They were seeing themselves through an “olfactory mirror”. What do you think? Do dogs understand the concept of the “self”?


A person’s understanding of themselves, others, and where they fit in society is crucial for their success as an individual. Self-understanding is often referred to by psychologists as theory of mind, and understanding the self can be easily tested in humans by something called a mirror self-recognition task. In this task, a person is marked with lipstick or a marker somewhere on their face, they look in the mirror, and they are able to notice that there is a mark on themselves and wipe it off. It seems very simple, but children sometimes can’t consistently understand and pass this test until the age of 3 or even older in some cases. Some primates have been shown to pass the mirror self-recognition task, and even dolphins and an elephant.

Dogs have not shown an interest in removing things like lipstick or fixing ruffled fur while looking in a mirror, but they have demonstrated the ability to use mirrors to find objects or food behind them. Sort of like how humans can use a mirror to watch TV from the bathroom…you know, if they wanted to. Since dogs have the ability to use mirrors efficiently, but don’t seem interested in grooming themselves to remove marks, scientists needed to come up with a new way to find out if dogs can understand their “selves”. While human beings primarily use sight to navigate the world, dogs rely much more heavily on scent to learn about their environments.

Due to this heavy reliance on smell, researchers devised a study comparing how long dogs sniff certain sample of urine. Yes, urine! It sounds gross, but as anyone with a dog knows, pups are super interested in smelling doggy pee. It can provide them with important social information. They found differences in how long the dogs smelled their own pee, another dog’s urine, and their own pee again – only with something added to it. Though the dogs couldn’t tell the researchers, “Hey! I did that! That one’s mine!”, they were able to tell us that they knew their own smell based on how long they smelled each liquid. The dogs smelled their own urine for significantly less time than the altered sample and the unknown sample. The dogs spent less time sniffing their own smell, because it was familiar, but the modified and unknown smells required more attention to understand what the scents represented. The researchers discussed how this might be evidence for self-awareness in dogs, even though they don’t pass mirror self-recognition tasks. Instead, the dogs seem to be able to recognize themselves in their “olfactory mirror”.

What do you think? Do dogs have a keen understanding of “the self”? Join the conversation @DogScienceWeekly on Instagram.


Where to find this article: Horowitz, A. (2017). Smelling themselves: Dogs investigate their own odours longer when modified in an “olfactory mirror” test. Behavioural Processes, 143, 17-24.

Thanks to @life_of_sora for letting us use their photo. Find them on Instagram!

bottom of page