Many people find zoos saddening: the animals often seem depressed and understimulated in dreary, unnatural settings. Hancocks (Animals and Architecture), an architect and director of the Open Range Zoo in Melbourne, Australia, confirms the accuracy of those impressions. He became concerned about the plight of zoo animals when, as a university student, he looked into a gorilla's intelligent eyes: "I walked away from London Zoo that day... feeling confused and depressed." This brilliantly researched and persuasive book traces the sociology of animal captivity back to Paleolithic times, when "wild animal ownership bestowed prestige and power." Speculating that the first zoo appeared in Sumeria 4,300 years ago, Hancocks explores zoo design, ecology and history worldwide. He praises certain model institutions, including the Bronx Zoo, Emmen Zoo in Holland and Seattle's Woodland Park Zoo. Otherwise, he stridently criticizes many zoo practices, such as "disjointed exhibits," cramped conditions and even bad cafeteria food. "My proposal is to uninvent zoos as we know them and to create a new type of institution, one that... engenders respect for all animals and that interprets a holistic view of Nature." Zoos shouldn't solely provide entertainment, he says, but should educate visitors about animals and encourage preservation of their natural habitats. They should also hold a multitude of species, not just the most popular or beautiful ones. Though the somewhat academic text loses steam midway, Hancocks's passion for creating humane environments for captive animals revives it at the end. Photos. (May)