Topographical Anatomy of the Dog By Dr. O. Charnock Bradley. Revised by Prof. Tom Grahame. Fourth edition. ... First, after the descriptions of most of the muscles, ...

New research shows domestication has altered dogs' facial structure such that they have a unique muscle allowing them to raise their inner eyebrows, but wolves do not.

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 ...