Your dog’s puppy dog eyes are a product of evolution – and are designed to help them communicate with you. That’s according to new research from the UK’s University of Portsmouth. They found that as dogs split off from wolves genetically, about 33-thousand years ago, dogs developed expressive eyebrows. They grew a muscle that allows them to raise the inner corner of the eyebrows – and you’re probably familiar with the look. It’s the one they give that says, “Please mom, may I have a treat if I look at you this way?”

The National Academy of Sciences says dogs evolved to interact with humans and tug on their heartstrings to increase their odds of survival. And wolves do NOT have that eyebrow muscle. They don’t need it – because they’re not trying to live with us and communicate with us. Just something to think about the next time your dog gives you “the look.”

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