It turns out that cats aren’t the only pets with a knack for manipulating their owners into doing their bidding.

New research reveals dogs developed “puppy dog eyes” specifically to tug at their owners’ heartstrings.

A study conducted by the National Academy of Sciences has found that the muscle dogs use to raise their eyebrows and increase their cute factor has developed in the years since canines became household pets.

The study claims the muscle appeared as dogs evolved because using it would net them food or affection.

As proof, researchers point to the ancestors of dogs. In wolves, the muscle is non-existent.