In three new books, learn how gender shapes language and development and discover the truth behind gender stereotypes.

Gender is a complex and never-ending story written over the course of a lifetime, according to neurobiologist Donald W. Pfaff in Man and Woman: An Inside Story (Oxford University Press, 2010). Male and female brains develop differently, starting in the womb. Studies show, for example, that male mice fetuses are bathed in the sex hormone testosterone, making them more aggressive than females.

In Conversation and Gender (Cambridge University Press, 2011), psychologists Susan Speer and Elizabeth Stokoe pull together evidence from domestic telephone calls, police-suspect interviews and psychiatric assessments to help explain how the sexes use language differently. For instance, some studies suggest that, on average, women tend to be better with words, exhibiting more diverse vocabularies and a keener eye for textual analysis.

Every year another work of popular psychology tries to convince readers that the male and female brains are as different as G.I. Joe and Barbie. Delusions of Gender (Norton, 2010), by cognitive neuroscientist Cordelia Fine, exposes the flaws in many studies that have provided a scientific foundation for stereotypes about gender differences. —Ferris Jabr