Sex and Gender as Unstable Categories

New York Times science writer Natalie Angier talks about her new book "Woman: An Intimate Geography." (Houghton Mifflin)She is also a Pulitzer Prize recipient for her writing in The Times. Her other books include: "The Beauty of the Beastly," and "Natural Obsessions." She lives in Takoma Park, Maryland.

Nationally syndicated sex advice columnist Dan Savage has written a collection of his Q & A's in "Savage Love" published by Plume books. He is also an associate editor at The Stranger, a weekly alternative paper in Seattle.

In her books and plays Bornstein, a transgender activist, argues the need for the acceptance of nontraditional gender roles, meaning those not defined as either male of female. In her book "Gender Outlaw: On Men, Women, and the Rest of Us," she writes about her sex-change experience and her view of society's conceptions of gender. She has also written the novel (with co-author Caitlin Sullivan) "Nearly Roadkill."