The Bergers do offer some intriguing particulars on how certain animals ""fit in"" (adapt) to a given habitat: the Anables fish of South America float with their eyes half above, half below the water line; birds get information from nerve endings at the base of their feathers. . . . But overall this worthy presentation of the concept is too diffuse to do more than echo, on a slightly more mature level, Jeanne Bendick's definition of Adaptation (1971). Supplementary.