Every dog owner knows how hard it can be to say no to "puppy-dog eyes," but a new study shines light on how canine facial expressions evolved and why humans are able to understand them so well.

New preliminary data offers insight into why we may find dogs to be so darn lovable. A study found that dogs generally have faster facial muscles than wolves—muscles that allow them to quickly react ...

African wild dogs might use facial expressions to communicate with each other as they hunt in packs on the savanna. Arno Meintjes via Flickr under CC BY-NC-SA 2.0 DEED Puppy-dog eyes are irresistible.

Smiles do more than express emotion - new research shows they can unconsciously influence trust and shape how we perceive ...