The reason why dogs lick their lips


The licking of lips is something that has endured throughout history. Humans and animals lick their lips and this is in preparation for something tasty, right? Well, that’s the common assumption, though it’s not strictly true. Yes, humans generally lick their lips in anticipation at the taste of something that’s likely to be truly delicious. But, when we’re talking about dogs, there’s actually a different reason.

It’s actually been suggested, in the journal Behavioral Processes, that lip licking is actually a form of dogs communicating with humans! We know that there are already lots of ways dogs choose to communicate with us, including barking, and the wagging of their tails. But, it seems that licking their lips is also another way of them communicating complex emotions and feelings to us.

What’s with the licking?

Okay, so it turns out that dogs actually lick their lips when they detect that humans are angry or upset. This is something that is based almost solely on visuals. It’s strange because we think of dogs as having poor vision, and that they make up for it in other areas. However, it now appears that dogs have slightly better vision than we first thought because they react to seeing us display negative emotions. This hints to dogs having a deeper understanding of human emotions that we might not have thought they had before.

The reason why dogs lick their lips

Running tests

During the testing part of the process, the most curious findings were revealed. The pooches were shown images of humans and dogs displaying either positive or negative facial features. And, at the same time, they were played audio clips conveying positive, negative, and neutral sounds. It turned out the dogs only licked their lips when they saw the images of humans with negative facial expressions, suggesting that visual stimuli is what plays the biggest role when dogs process human emotion.

Other findings

The dogs were tested over a period of a fortnight apart and were presented with every possible combination. It turned out that the lip licking occurred on a more frequent basis when the dogs were shown images of a human displaying negative emotions as opposed to a fellow dog. This could indicate that years of domestication has altered dogs’ perceptions and that they are now more attuned to human emotions and responses than to their own.

Dogs are smart

This puts to bed one of the common misconceptions surrounding household pets – cats are smart, dogs are dumb. But, it turns out that dogs are actually pretty smart too! You think cats could simply look at our facial expressions, and, not only understand that we are upset, but also emote with us? Dogs are continuing to surprise us in a lot of different ways, and this is just one of them.

The reason why dogs lick their lips

The next time you see a dog licking its lips, you will think “Oh, my pooch is hungry!” Instead, you’ll know that your dog has seen the anger or negativity on your face, and is doing what they can to communicate with you. They’re showing you they care for you, and they love you, and that’s a pretty amazing thing.