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University of California Press

About the Book

In this innovative celebration of diversity and affirmation of individuality in animals and humans, Joan Roughgarden challenges accepted wisdom about gender identity and sexual orientation. A distinguished evolutionary biologist, Roughgarden takes on the medical establishment, the Bible, social science—and even Darwin himself. She leads the reader through a fascinating discussion of diversity in gender and sexuality among fish, reptiles, amphibians, birds, and mammals, including primates. Evolution's Rainbow explains how this diversity develops from the action of genes and hormones and how people come to differ from each other in all aspects of body and behavior. Roughgarden reconstructs primary science in light of feminist, gay, and transgender criticism and redefines our understanding of sex, gender, and sexuality. Witty, playful, and daring, this book will revolutionize our understanding of sexuality.

Roughgarden argues that principal elements of Darwinian sexual selection theory are false and suggests a new theory that emphasizes social inclusion and control of access to resources and mating opportunity. She disputes a range of scientific and medical concepts, including Wilson's genetic determinism of behavior, evolutionary psychology, the existence of a gay gene, the role of parenting in determining gender identity, and Dawkins's "selfish gene" as the driver of natural selection. She dares social science to respect the agency and rationality of diverse people; shows that many cultures across the world and throughout history accommodate people we label today as lesbian, gay, and transgendered; and calls on the Christian religion to acknowledge the Bible's many passages endorsing diversity in gender and sexuality. Evolution's Rainbow concludes with bold recommendations for improving education in biology, psychology, and medicine; for democratizing genetic engineering and medical practice; and for building a public monument to affirm diversity as one of our nation's defining principles.

About the Author

Joan Roughgarden is Professor of Biology Emerita at Stanford University. She is the author of several books, including Evolution and Christian Faith: Reflections of an Evolutionary Biologist and The Genial Gene: Deconstructing Darwinian Selfishness (UC Press).

Table of Contents

Preface to the 2013 Edition
Preface to the 2009 Edition
Introduction: Diversity Denied

PART ONE: ANIMAL RAINBOWS
1 Sex and Diversity
2 Sex versus Gender
3 Sex within Bodies
4 Sex Roles
5 Two-Gender Families
6 Multiple-Gender Families
7 Female Choice
8 Same-Sex Sexuality
9 The Theory of Evolution

PART TWO: HUMAN RAINBOWS
10 An Embryonic Narrative
11 Sex Determination
12 Sex Differences
13 Gender Identity
14 Sexual Orientation
15 Psychological Perspectives
16 Disease versus Diversity
17 Genetic Engineering versus Diversity

PART THREE: CULTURAL RAINBOWS
18 Two-Spirits, Mahu, and Hijras
19 Transgender in Historical Europe and the Middle East
20 Sexual Relations in Antiquity
21 Tomboi, Vestidas, and Guevedoche
22 Trans Politics in the United States

Appendix: Policy Recommendations
Notes
Index

Reviews

“As a compendium of information on sex and gender diversity in the natural world, Roughgarden's is the richest and most authoritative book available, fulfilling a desperate need of readers both within and outside the scientific community . . . this book is going to have a huge impact.”
Nature
“This brilliant and accessible work of biological criticism has the potential to revolutionize the way readers conceive of gender and sexuality in the natural world. “
Publishers Weekly
“An insightful blend of biology and social science, this work presents a fresh evolutionary perspective on sex, gender, and sexuality, with widespread implications for modern societies.”
CHOICE
“The book is thought–provoking, even at times profound. . . . I hope this book will be widely read. It combines the combustible power of a keen intellect with powerful conviction and ethical courage. Scientists are trained to create the illusion of objectivity by hiding their hopes and expectations. Roughgarden tries a different approach, openly injecting her reasoned convictions and policy agenda into her analyses. I don't agree with all of her conclusions, but she has written an important and honest book about a subject that matters.”
American Scientist
“Throws open the animal kingdom’s closet doors.”
Advocate
“This extraordinary study strengthens the case for a liberal tolerance and blows open established moral and scientific certainties.”
Scotsman
“Brave . . . Evolution’s Rainbow succeeds very well at making the reader rethink their conceptions of social selection and nature.”
Biology Digest
Evolution’s Rainbow not only enhances our knowledge of the natural world, it also offers an ethical way for such knowledge to be used.”
California Wild
‘A fascinating discussion of diversity in gender and sexuality across a wide variety of animals.”
Pink Pages
"Evolution's Rainbow is an expansively creative challenge to the modern orthodoxies of sexual selection. Roughgarden's intellectual generosity may jump-start the careers of a new generation of diversity-affirming Darwinian scientists."—Patricia Adair Gowaty, author of Feminism and Evolutionary Biology

"An entrancing tale of sexual ambiguity in animals and people, but also that rarest of literary beasts—a science book written from the heart."—Steve Jones, author of Darwin's Ghost

"A thoughtful and scholarly, yet deeply personal, perspective from a brilliant theoretical biologist. This articulate and provocative disquisition is must reading for anyone fascinated by one of the most important contemporary social challenges."—Simon Levin, author of Fragile Dominion

"This book challenges not only the assumptions about male-female differences in behavior and homosexual-heterosexual differences, but also the very meanings of ‘maleness’ and ‘femaleness’ in physical and biological terms. Roughgarden builds a strong case for biological diversity related to what humans call sex, gender, and sexuality."—Bonnie Spanier, author of Im/partial Science: Gender Ideology in Molecular Biology

"Joan Roughgarden asks, and indeed tries to answer, all the big questions about sexual diversity among humans and animals. She takes her readers on a wonderful journey through ecology and evolution and is a brilliant and talented narrator. Evolution's Rainbow will fundamentally change many ongoing conversations on sexuality and science."—Judith Halberstam, author of Female Masculinity

"Every now and then science focuses on a subject that matters. Gender and gender differences matter to us social primates. And we will judge, condemn, restrict or incarcerate people based on our notions of biologically normal variability in gender and sexuality. Thus, it is immensely important when a book comes along, written clearly and authoritatively by an eminent scientist, that demonstrates how wrong most people’s ideas are about this subject. This is such a book."—Robert Sapolsky, author of A Primate’s Memoir