Introduction to Animal Behavior by R.J. Siiter
With more emphasis than usual on the behavior of vertebrates and primates (although the author still includes classic bird and insect studies) the book examines how wild animals live, survive, and reproduce in their natural, wild habitats.

For the Love of a Dog: Understanding Emotion in You and Your Best Friend
While we may never be absolutely certain what our dogs are feeling, with the help of this riveting book we can understand more than we ever thought possible.