A Harvard biologist explains the real science behind the popular sci-fi TV show. With its huge cast of alien life-forms (some with powers and senses no human can match), Star Trek would appear to flout the most basic characteristics of life as we know it. But, as Andreadis points out, no matter how exotic the cast, certain Earth-based assumptions remain valid. Silicon may be able to substitute for carbon on some distant planet, but organisms based on it will be subject to gravity and electromagnetism, as well as having some form of genetic code to permit continuity of form and function as the beings reproduce. Sensory organs will still be necessary to receive information from the environment. In addition, the Trek universe is populated by a variety of machine intelligences ranging from the android Lt. Commander Data to sentient computer viruses. Andreadis uses these various fictional examples (and others drawn from such films as Bladerunner and print science fiction) to explain the current state of biological knowledge. This takes her into subjects ranging from the nature of immortality or telepathy to the problems of universal translating machines--all of which throw considerable light on the dark comers of biology. She notes the general sameness and blandness of the various cultures encountered by the Enterprise and its crew--generally humanoid, with far less social variation than a five-year voyage on Earth would be likely to uncover--but recognizes that by Hollywood standards, this is adventurous stuff. And while she pokes fun at other Hollywood conventions, such as the ""Snugglability Quotient""--alien Good Guys tend to be cute and fuzzy while Bad Guys look like refugees from the Black Lagoon--her affection for the material is always clear. And she deftly maintains the effective blend of entertainment and instruction that characterized The Physics of Star Trek (not reviewed). An entertaining book that deserves an audience well beyond sci-fi fandom.