One of the founders of modern human biology and physical anthropology, Gabriel W. Lasker holds a well-established place in the history of science. In a classic article published in Science in 1969, Lasker advanced the idea of plasticity, the process of human adaptation to stressful environments by a series of modifications to the body during the course of physical growth and development.

This concept was a factor that led the scientific community to give up its reliance on the notion of genetically fixed racial types. As he documents the rapidly changing field of anthropology and some of its leading figures, Lasker gives his readers a peek inside the lives of people who have defined what it means to be human - and one of those people is himself.