Mutants: On Genetic Variety and the Human body discusses exactly what it says it does. The physical effects of altered or missing genes on the various parts of the human body are discussed in some detail. Some of the "mutations" discussed in the book include conjoined twins, mermaid syndrome, cyclops syndrome, pygmies, giants, hermaphrodites, skin and skeletal issues and aging. This book is extremely interesting, without being distasteful or gory. The science (real science!!) is understandable but not overly simplified. Black and white illustrations are included regularly.