Mary Roach is the author of Stiff: The curious Lives of Human Cadavers and Spook: Science Tackles the Afterlife. Her writing has appeared in Salon, Wired, National Geographic, New Scientist, and the New York Times Magazine. Her latest book is Bonk: the Curious Coupling of Science and Sex.

In this conversation with D.J. Grothe, Mary Roach reveals why she looks to science rather than to religion for answers about death and sex, and why she is interested in such topics in the first place. She talks about the history of sex research, including Leonardo Da Vinci's anatomical explorations of coitus, as well as 19th century sex research connected to fertility and STDs. She talks about religious opposition to scientific research of human sexuality, and how it affects funding. She describes some on Alfred Kinsey's research that showed the diversity of sexual activity in the United States. She details various scientific attempts to improve human sexuality, including grafting additional testicles on men, or surgically relocating women's clitorises. She explores the role of the placebo effect in certain sexual cures, such as for impotence or increased arousal. And she talks about the link between sexual satisfaction and overall happiness.