Female human evolution and its role in human history are central to the book. Since the beginning of evolutionary science, people have tended to look at human evolution from a male perspective, focusing on how male hominins have evolved into male humans. However, Bohannon asserts that the female sex has been leading human evolution for millions of years, and she clarifies that it is critically important to understand the history of the female body in evolutionary terms to understand the evolutionary disaster to come if female individuals continue to face sexism and gender-based limitations. Human evolution has depended on humans’ female ancestors developing the traits and tools that allowed them and their descendants to have healthy babies and find food. The evolution of the female body has contributed to the growth of humanity and the continuing evolution of the race in seven major ways: the formation of breast milk and nipples; the development of the uterus and childbirth; the heightening of senses; bipedalism; toolmaking in the form of weapons, eating tools, and gynecology; language and communication; and menopause.

Mammals’ development of lactation and humans’ development of nipples and raised breasts were essential to the growth of the human species and the nurturing of young.