Dog side eye, aka ‘the shady gaze’, is the subject of many seemingly humorous memes. But this canine characteristic is often more loaded than the videos suggest.
Humans give side eye as an expression of doubt, scorn or disapproval, which is why it’s so amusing to see in dogs. It occurs when the coloured part of the eye, known as the iris, swivels to the side, to reveal more of the white part, known as the sclera.
In dogs, this charismatic look is often accompanied by other non-verbal gestures, such as flattened ears and a slight turning away of the head. This gives animal behaviourists some insight into its meaning.
Dogs give side eye for various reasons. When the cocker spaniel next door encounters our cat, for example, her sardonic look of ‘oh, really?’ belies the fact that she’s actually anxious (and with good reason: our cat is a nightmare).
She makes the same expression when our dog is guarding a desirable treat. In this case, the avoidance of direct eye contact is her way of saying: ‘If I’m not looking at you, I can’t possibly be plotting theft.’ It works too. She spots the instant that our dog drops his guard and the treat is in her belly before you can so much as shout: ‘Stop! Thief!’
In other dogs in other instances, ‘half-moon eye’ may also be used to convey different emotions, such as feeling protective or territorial.
Dogs owe this expressive capability to the whites of their eyes, which are an anomaly in the animal kingdom. Most animals don’t have white sclerae. It’s thought that, during domestication, our ancestors may have inadvertently selected for dogs with white sclera, because it aided communication between our two species. The funny videos were an unexpected by-product!
Read more:
- 6 simple ways to instantly improve your dog’s life, according to science
- Puppy love: How science explains our special bond with dogs
- The (incredibly adorable) reason your dog stares at you
Asked by: Tyrone Chase, via email
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