Can a parrot understand complex concepts and mean what it says? Since the early 1900s, most studies on animal-human communication have focused on great apes and a few cetacean species. Birds were rarely used in similar studies on the grounds that they were merely talented mimics--that they were, after all, "birdbrains." Experiments performed primarily on pigeons in Skinner boxes demonstrated capacities inferior to those of mammals; these results were thought to reflect the capacities of all birds, despite evidence suggesting that species such as jays, crows, and parrots might be capable of more impressive cognitive feats.

Twenty years ago Irene Pepperberg set out to discover whether the results of the pigeon studies necessarily meant that other birds--particularly the large-brained, highly social parrots--were incapable of mastering complex cognitive concepts and the rudiments of referential speech. Her investigation and the bird at its center--a male Grey parrot named Alex--have since become almost as well known as their primate equivalents and no less a subject of fierce debate in the field of animal cognition. This book represents the long-awaited synthesis of the studies constituting one of the landmark experiments in modern comparative psychology.

Pepperberg bought Alex--a parrot of average intelligence and without lofty pedigree or training--from a pet store when he was 1. Since working with Pepperberg, he has developed a 100-word vocabulary and can identify 50 different objects, recognizing quantities up to six, distinguishing seven colors and five shapes, and understanding the difference between big and small, same and different, over and under. He can tell you, for instance, that corn is yellow even if there is no corn in view, as well as correctly select the square object among various shapes and identify it verbally. What this all means, stresses Pepperberg, is that Alex is not merely parroting but actually thinking; he bases answers on reason rather than instinct or mimicry.

Though the anecdotes are rich and Alex makes a lively subject, this is principally a research paper relying on intricate details and a prodigious amount of data (the notes and references alone run to 79 pages). This is not light reading, particularly for the layperson. Still, The Alex Studies manages to be more than a valuable contribution to science, for in providing ample evidence of our similarities to other creatures, the book ultimately calls into question the concept of human supremacy over the animal kingdom. Pepperberg's stated goal is "to provoke awareness in humans that animals have capacities that are far greater than we were once led to expect, and to remind us that all we need to examine these capacities are some enlightened research tools." She has provided such tools in this seminal work. --Shawn Carkonen