The debate over "nature versus nature" continues over the causes of homosexuality. Is there a gay gene? Is there something about the way a child is raised that can "turn" her gay? Or is being gay simply a "choice"? Taking a look at the major genetic, biological, and psychological theories of the origins of homosexuality, this book asks questions about gender, gender identity, and sexual orientation that are at the center of gay people's sense of identity and their struggle for civil rights and acceptance by society. While for centuries homosexuality was considered a mental illness, a moral failure, or a biological disorder, gay people in the twenty-first century have the evidence of scientific research and their authentic experiences of happy and fulfilling lives to support the pride and sense of community that is their rightful place in the modern world.

What causes a child to grow up gay or straight? In this book, neuroscientist Simon LeVay summarizes a wealth of scientific evidence that points to one inescapable conclusion: Sexual orientation results primarily from an interaction between genes, sex hormones, and the cells of the developing body and brain. In this revised edition LeVay broadens his horizons. He adds a new chapter on bisexuality, reviews some uncommon forms of sexuality such as asexuality and pedophilia, and considers whether there could be a biological basis for subtypes of gay people such as "butch" and "femme" lesbians.

This text reviews what research on animals can tell us about the biological factors that control human sexual behavior and orientation.

Are people born gay, or does upbringing or even personal choice play a part? The row between gay rights activists and the conservative lobby over this question has now raged for over a decade. Combining their own findings with research, the authors provide an overview of the work that has been done in this field.

The first authoritative summary of its kind in this area, the Handbook of Psychology and Sexual Orientation is the primary resource for the many researchers, including a new generation of investigators, who are continuing to advance understanding in this field. The volume editors along with other leading experts, contribute an extraordinary review of contemporary psychological research and theory on sexual orientation in their specific fields of work.

Genetic, hormonal, neurological, and other biological factors need to be taken into account to fully understand sexual orientation. This work represents the latest research and theory on causes of variation in sexual orientation. It looks at sexual orientation as a cross-species phenomenon with numerous determining factors. This work is a collection of chapters by some of the leading researchers in the scientific study of sexual orientation. The theory that many genetic, hormonal, neurological, and other biological factors need to be taken into account to fully understand sexual orientation is espoused in this book. It presents much of the latest research on the causes of variation in sexual orientation and related phenomena. It views sexual orientation as a cross-species phenomenon with both biological and environmental determinants.

Front-page headlines last July reported the discovery of a gene marker for male homosexuality. Now the scientist who made the discovery describes his history-making research and the far-reaching implications of this first genetic link to behavior.