Odd Couples: Extraordinary Differences Between the Sexes in the Animal Kingdom

While we joke that men are from Mars and women are from Venus, our gender differences can't compare to those of other animals. For instance: the male garden spider spontaneously dies after mating with a female more than fifty times his size. Female cichlids must guard their eggs and larvae--even from the hungry appetites of their own partners. And male blanket octopuses employ a copulatory arm longer than their own bodies to mate with females that outweigh them by four orders of magnitude. Why do these gender gulfs exist? Introducing readers to important discoveries in animal behavior and evolution, Odd Couples explores some of the most extraordinary sexual differences in the animal world. From the fields of Spain to the deep oceans, evolutionary biologist Daphne Fairbairn uncovers the unique and bizarre characteristics--in size, behavior, ecology, and life history--that exist in these remarkable species and the special strategies they use to maximize reproductive success. Fairbairn describes how male great bustards aggressively compete to display their gorgeous plumage and large physiques to watching, choosey females. She investigates why female elephant seals voluntarily live in harems where they are harassed constantly by eager males. And she reveals why dwarf male giant seadevils parasitically fuse to their giant female partners for life. Fairbairn also considers humans and explains that although we are keenly aware of our own sexual differences, they are unexceptional within the vast animal world.

Looking at some of the most amazing creatures on the planet, Odd Couples sheds astonishing light on what it means to be male or female in the animal kingdom.

"If you want to find out why adult male elephant seals can weigh more than four times as much as an adult female, whereas female blanket octopuses are truly enormous compared to their tiny male partners, this fascinating book is for you. Daphne Fairbairn not only introduces us to some exceptional animals but she also provides evolutionary explanations for why males are much larger (or much smaller) than females of their species. A great topic and a great read for layperson and biologist alike."--John Alcock, author of Animal Behavior: An Evolutionary Approach

"Odd couples indeed! Fairbairn takes us on a journey through oceans, grasslands, beaches, and backyards, plunging us into the worlds of nature's most weird and wonderful creatures, all to answer one question: why are males and females different? By tackling extremes--such as male octopuses forty thousand times lighter than their mates, and parasitic male seadevils who fuse themselves to the bellies of females--she deftly illustrates how a common set of concepts can connect them all. A thoroughly enjoyable read."--Doug Emlen, coauthor of Evolution: Making Sense of Life

"A fascinating natural history account of some extreme and unfamiliar examples of sexual differences among animals. A real eye-opener."--Mark Elgar, University of Melbourne

"This unique, ambitious, and engaging book educates general readers about animal behavior, physiology, life history, and evolution using sex differences as its theme. Quite an achievement and a pleasure to read."--Allen J. Moore, University of Georgia

Daphne J. Fairbairn is professor of biology at the University of California, Riverside. She has written widely on the science of sexual differences and is the coeditor of "Sex, Size, and Gender Roles".

Chapter 1: Introduction 1

Chapter 2: The Roots of Sexual Differences: Why Male and Female Animals Differ 9

Chapter 3: Elephant Seals: Harems, Hierarchies, and Giant Males 23

Chapter 4: Great Bustards: Gorgeous Males and Choosy Females 46

Chapter 5: Shell-Carrying Cichlids: Protective Males and Furtive Females 64

Chapter 6: Yellow Garden Spiders: Sedentary Females and Roving Males 81

Chapter 7: Blanket Octopuses: Drifting Females and Dwarf Males 104

Chapter 8: Giant Seadevils: Fearsome Females and Parasitic Males 116

Chapter 9: Bone-Eating Worms: Female Tubeworms with Harems of Minuscule Males 133

Chapter 10: Shell-Burrowing Barnacles: Sac-Like Females with Harems of Phallic Males 147

Chapter 11: The Diversity of Sexual Differences: Differences between Males and Females across the Animal Kingdom 160

Chapter 12: Concluding Remarks 187

Acknowledgments 195

Appendix A: Scientific Names Corresponding to Common Names Used in the Text 197

Appendix B: Summary of Sexual Dimorphisms by Animal Phylum 203

Notes 207

Glossary of Technical Terms 239

Sources 247

Illustration Credits 287

Index 289