Pulitzer Prize–winning science journalist Franklin (Molecules of the Mind
) draws on a slew of disciplines—evolutionary theory, zooarcheology, behavioral science, ethnology, bio-philosophy and keen firsthand observation—to formulate a challenging but enticingly plausible theory about the psychological leash binding humans and canines. His thesis: beginning about 12,000 years ago, as wild wolves evolved into “follower wolves” and were subsequently domesticated by early man, a kind of mind meld occurred. As this neurological attachment took shape, the dog shed 20% of its brain mass because, biologically, humans had “agreed to do its thinking” for it, while mankind lost 10% of its brain mass because dogs became “our beast of emotional burden.” Franklin buttresses his inventive assertion with a combination of absorbingly loquacious ruminations on the behavior of his own dog, Charlie, and a rigorous compilation of scientific facts rooted in a decade of study about the nature of wolves and dogs. As concepts of the canine go, Franklin's is notably audacious. And among a plethora of books on breeding, disciplining, loving and lamenting the loss of man's best friend, this thoughtful discourse is a best of breed. (Sept.)