'Why Is Sex Fun? The Evolution of Human Sexuality' is a 1997 book about the evolution of human sexuality by the biologist Jared Diamond.

Summary

Diamond addresses aspects of human sexuality such as why women's ovulation is not overtly advertised (concealed ovulation); why humans have sex in private rather than in public like other mammals; and why the ovaries are U-shaped. The book is divided into 7 chapters: Some signals are genuinely beneficial like certain muscles in males and fat breasts/hips in females, while some mean nothing like pitch of voice, hair, etc. The author proposes that fat deposits in a woman's body are concentrated in breasts and hips as an indication to men that the woman has better lactation abilities and a larger birth canal.

Publication history

Why Is Sex Fun? was published in 1997 by Basic Books, as part of the Science Masters series.

Reception

Why Is Sex Fun? received a positive review from the biologist Steve Jones in The New York Review of Books. Jones described the book as engaging and interesting. However, he questioned Diamond's treatment of concealed ovulation, finding it inconclusive. The anthropologist Peter B. Gray and the evolutionary biologist Justin R. Garcia maintained that Why Is Sex Fun? was one of the best-read books on human sexuality. However, they considered it "informative but too thin in substance".