In this controversial culmination of a lifelong quest, Alexander F. Skutch, a well-known ornithologist who has studied birds for more than sixty years, makes a case for "believing that birds' mental capacities have been grossly underestimated." Lacking hard scientific proofs of what birds think and feel, we are left, Skutch argues, with inferences gleaned from observation of their behavior. His intimate, six-decade study of tropical and north temperate birds and his wide survey of the literature inform this remarkable review of the psychic life of birds. Although varying widely by species,...