What makes people gay? In this hour of To the Best of Our Knowledge, the complex origins of homosexuality, including the confusing search for the "gay gene" and words from a gay man who embraces Freud. Also a conversation with a biologist who's catalogued same-sex relationships in the animal world.

Research psychiatrist Kenneth Kendler explains to Steve Paulson what we really know about the so-called "gay gene." He says there may be a slight genetic predisposition to homosexuality in some men, but environmental factors are also crucial. Also, Andrew Sullivan tells Steve Paulson that he's been reading Freud and finds his views on homosexuality remarkable nuanced and tolerant. Sullivan is senior editor of The New Republic and author of "Love Undetectable: Notes on Friendship, Sex, and Survival."

Biologist Bruce Bagemihl tells Judith Strasser about some of the same sex behaviors he's catalogued in the animal world, and outlines his thesis that biology is fueled by an abundance of energy in nature. His book is "Biological Exuberance: Animal Homosexuality and Natural Diversity."

Joan Drury tells Judith Strasser why she writes mystery novels, and why people like to read them. Drury's protagonist is a radical feminist lesbian activist and a journalist with investigative skills. She appears in the mysteries "Silent Words," "The Other Side of Silence," and "Closed in Silence." Also, Joe Karaszewski is a graduate student at the University of Wisconsin, and he's HIV positive. He tells Jim Fleming why he's participated for two years in the Minneapolis - Chicago AIDS (Bicycle) Ride, and how he's able to do it.

Distribution dates:

• week of 05/23/99 - hour 2