A basic biology text rather than a light reading exercise. As such it is an excellent account of animal organisms on the earth. Ranging from tiny one-celled creatures through the usual organizations of multicellular communities to ever more differentiated species, the text is very lucid and interestingly written. It touches on such diverse topics as genetics and mutations, dinosaurs and the search for evolutionary records, and the role of sanctuaries in the preservation of animals. This is a very straightforward and moderately heavy work, adequate and accurate. It is similar in style and content but perhaps set at an easier reading level than the 1959 textbook Animal Life by the same authors.