Gay, Straight, and the Reason Why: The Science of Sexual Orientation

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Oxford University Press, Sep 30, 2010 - Social Science - 432 pages
4 Reviews
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. LeVay helped create this field in 1991 with a much-publicized study in Science, where he reported on a difference in the brain structure between gay and straight men. Since then, an entire scientific discipline has sprung up around the quest for a biological explanation of sexual orientation. In this book, LeVay provides a clear explanation of where the science stands today, taking the reader on a whirlwind tour of laboratories that specialize in genetics, endocrinology, neuroscience, cognitive psychology, evolutionary psychology, and family demographics. He describes, for instance, how researchers have manipulated the sex hormone levels of animals during development, causing them to mate preferentially with animals of their own gender. LeVay also reports on the prevalence of homosexual behavior among wild animals, ranging from Graylag geese to the Bonobo chimpanzee. Although many details remain unresolved, the general conclusion is quite clear: A person's sexual orientation arises in large part from biological processes that are already underway before birth. LeVay also makes it clear that these lines of research have a lot of potential because--far from seeking to discover "what went wrong" in the lives of gay people, attempting to develop "cures" for homosexuality, or returning to traditional explanations that center on parent-child relationships, various forms of "training," or early sexual experiences--our modern scientists are increasingly seeing sexual variety as something to be valued, celebrated, and welcomed into society.

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User Review  - bness2 - LibraryThing

This is a good overview of what science currently has to say about the biological underpinnings of sexual orientation. The author himself is gay, which lends more credence to his apparently even ... Read full review

LibraryThing Review

User Review  - HonourableHusband - LibraryThing

This is a necessary book, which comes at an important time. Back in 1991, LeVay made one of the key scientific breakthroughs in understanding the dynamics of sexal orientation. Since then, he's ... Read full review


What Is Sexual Orientation?
Why We Need Biology
The Outline of a Theory
Characteristics of Gay and Straight Adults
The Role of Sex Hormones
The Role of Genes
The Brain
The OlderBrother Effect
Author Index
Subject Index

The Body

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About the author (2010)

Simon LeVay is a British-born neuroscientist who has served on the faculties of Harvard Medical School and the Salk Institute for Biological Studies. He has written ten previous books, including the New York Times best-seller, When Science Goes Wrong.

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