(Note: This program originally aired back in the fall.) Our guest is Dr. Sarah E. Hill, a professor at TCU in Ft. Worth, Texas. She's seen as an authority on evolutionary approaches to psychology and health, and her new book, which she tells us about, is "This Is Your Brain on Birth Control: The Surprising Science of Women, Hormones, and the Law of Unintended Consequences." As was noted of this work by Dr. Jolene Brighten (author of "Beyond the Pill"): "[This book] validates what generations of women have suspected since the introduction of the pill--birth control is doing a whole lot more in our bodies than simply preventing pregnancy. In this brilliant and witty exploration of what we know (and don't know) about birth control, Hill has provided sound evidence that is eye-opening, riveting, and a must read for all women and the people who care about them."