A lot of people have theories about the behaviors and personalities of dogs. Some folks believe in harsh training -- the alpha mode of pet ownership -- while others treat their dogs like toys to spoil and dress up.

Alexandra Horowitz, a cognitive scientist as well as a dog lover, digs a little deeper, trying to discover what truly makes a canine tick.

It's fascinating reading.

Horowitz notes from the start the human tendency to anthropomorphize their pets, assigning human motivations and attitudes toward animals that wouldn't share them. At the same time, she acknowledges the error of assuming too much about the canine heritage, descended from a wolf-like ancestor but with traits that evolved on a very different track.

She devotes the book to a more cerebral study, lovingly punctuated with insights gained watching her own beloved dog, Pumpernickel. She discusses traits that are common to the domesticated dog, and the manner in which they differ from wolves and wild dog-like species. She explores a fascinating experiment that attempted to direct the evolution of a group of foxes into dog-like pets. She explains how a dog's senses -- heightened in some areas, such as scent and hearing -- affect the dog's perception of the world. She looks at the reasons that bonding occurs between person and dog in a way that's rare among other species.

When studies have been done, she discusses their findings. She uses her own observations to illustrate behaviors in a way that personalizes what could have been a dry text. But no, anyone who loves dogs -- and who has, staring into their eyes, wondered what they are thinking -- will enjoy this well-researched, well-presented exploration of the canine world.