Why Do Dogs Lick Their Lips?

Why Do Dogs Lick Their Lips?

Last update: 04 August, 2018

Dogs and humans have lived alongside each other since the Paleolithic period, which explains why both have developed certain means of communication. It’s already well-known that dogs express themselves by wagging their tail, or yawning. However, there’s still a lot more to know. For example, why do dogs lick their lips?

A recent study by British and Brazilian scientists has discovered something new in canine communication. They lick their lips in response to a very surprising stimulus…

Food and Uncertainty

It’s quite common for people to think that dogs lick their lips because they’re salivating too much. Maybe it’s time to eat or they can smell something delicious. However, previous studies on canine behaviour have also shown that this gesture is a response of uncertainty.

Now, through a study published in the famous journal, Behavioural Processesit’s been shown that this act is related to other visual stimuli.

Study Published in ‘Behavioural Processes’

The study involved exposure to different visual and audio stimuli, followed by analysis of the dogs’ responses.

After a thorough study, they discovered that dogs lick their lips as a response upon seeing that their owners are annoyed. Natalia Albuquerque, the main author of the study, said, “Mouth-licking was triggered by visual cues only”, in other words, human facial expressions. Audio stimuli of annoyed voices did not trigger the same response.

A dog which licks to lick their lips

Perception and Domestication

This conclusion opens the door to a brand new understanding of dog behavior and their perception of human emotions. Likewise, the scientists responsible for this discovery have suggested that this way of perceiving emotions is a consequence of selection during their domestication.


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