This little curiosity will attract science-fiction buffs--and perhaps a wider audience. The opening chapters intriguingly remind us that the sensory perceptions of human beings represent only a tiny portion of the perceptual resources on earth, much less in other imaginable biospheres. A dog lives in a sense-world that would be unrecognizable to us; a bee with its infinitesimal brain can ""calculate"" a direct return path from the most tortuous journey by ""measuring"" distances and angles with reference to polarized light. On the basis of such homegrown wonders, the Jonases posit and describe a few imaginary races (the Olfaxes, the Apistarians, the Hydronians) that we might expect to find on planets with differing gravitational, atmospheric, and electromagnetic conditions. (A pity smithsonian magazine's delightful pictorial variations on the same theme couldn't have been recycled for this purpose.) In a more introspective vein, they analyze social organizations based on extrahuman ""intelligence ""--i.e ., ant colonies, whose actions are fitted as precisely' to the organism's ends (through division of labor) as our own actions with their reliance on conscious individual decision. Current norms of perception and behavior, the Jonases rather blurrily suggest, may be only a transitional stage in the evolution of man; our neocortex may barely have begun to assume the ""group brain"" function 'which they claim is its ultimate potential. A big ragbag of materials with more than its share of logical holes (why assume that extraterrestrials will reproduce like mammals?) and muddled facts (a survey of changing cultural values since Egypt and Sumer is especially half-baked). Still, it also has more than its share of sane and likable moments.