Homosexual Behaviour in Animals

Behavioural observations from both the field and captivity indicate that same-sex sexual interactions are widespread throughout the animal kingdom, and occur quite frequently in certain non-human species. Proximate studies of these phenomena have yielded important insights into genetic, hormonal and neural correlates. In contrast, there has been a relative paucity of research on the evolutionary aspects. Homosexual Behaviour in Animals seeks to readdress this imbalance by exploring animal same-sex sexual behaviour from an evolutionary perspective. Contributions focus on animals that routinely engage in homosexual behaviour and include birds, dolphin, deer, bison and cats, as well as monkeys and apes, such as macaques, gorillas and bonobos. A final chapter looks at human primates. This book will appeal to graduate students and researchers in evolutionary biology, biological anthropology, zoology, evolutionary psychology, animal behaviour and anyone interested in the current state of knowledge in this area of of sexology.

VOLKER SOMMER obtained his Ph.D. from the University of Göttingen, Germany and is now Professor of Evolutionary Anthropology at University College London. His empirical research focuses on social and sexual behaviour in primates. He is involved in long-term eco-ethological studies of langur monkeys in India (since 1981), of gibbons in Thailand (since 1990) and of chimpanzees in Nigeria (since 1999).

PAUL L. VASEY obtained his Ph.D. from the Université de Montréal, Canada and is now an Associate Professor in the Department of Psychology & Neuroscience at the University of Lethbridge, Lethbridge, Alberta, Canada. His behavioural and neuro-anatomical research focuses on understanding the development and evolution of female homosexual behaviour in Japanese macaques. He currently conducts research on free-ranging macaques at Arashiyama, Japan.

Homosexual
Behaviour in
Animals

An Evolutionary
Perspective

---

Edited by

VOLKER SOMMER

PAUL L. VASEY

CAMBRIDGE UNIVERSITY PRESS
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Cambridge University Press
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Published in the United States of America by Cambridge University Press, New York

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© Cambridge University Press 2006

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First published 2006

Printed in the United Kingdom at the University Press, Cambridge

A catalogue record for this publication is available from the British Library

ISBN-13 978-0-521-86446-6 hardback
ISBN-10 0-521-86446-1 hardback

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Contents

Contributors

Ludek Bartoš

Ethology Group, Research Institute of Animal Production (VUZV),
10-Uhrineves CZ 104 00 Praha, Czech Republic

Barbara Fruth

Max-Planck-Institut für Verhaltensphysiologie, 82319 Seewiesen, Germany

Josef Hemetsberger

Konrad-Lorenz-Forschungsstelle für Ethologie, A-4645 Grünau 11, Austria

Gottfried Hohmann

Max-Planck-Institut für Evolutionäre Anthropologie, Deutscher Platz 6,
04103 Leipzig, Germany

Jana Holečková

Department of Zoology, Faculty of Science, Charles University, Prague &
Global Relation Department, Ministry of Environment of The Czech
Republic, Prague, Czech Republic

Rodney L. Johnson

Mannheimer Foundation, 20155 SW 360th St., Homestead, FL 33034, USA

Ellen Kapsalis

University of Miami, Division of Veterinary Resources, South Campus
Research Facility, 12500 SW 152nd St., Miami, FL 33177, USA

Catherine E. King

Diergaarde Blijdorp, Royal Rotterdam Zoological and Botanical Gardens,
Postbus 532 3000 AM Rotterdam, The Netherlands

Kurt Kotrschal

Konrad-Lorenz-Forschungsstelle für Ethologie, A-4645 Grünau 11, Austria

Diana Kyriazis

Department of Anthropology and Department of Experimental Psychology,
University of Oxford, South Parks Road, Oxford OX1 3UD, United Kingdom

Janet Mann

Department of Psychology & Department of Biology, Georgetown
University, 37th and O Street NW, Washington, DC 20057, USA

Catherine Roden

Royal Zoological Society of Antwerp, Center of Research and Conservation,
K. Astridplein 26, B-2018 Antwerp, Belgium

Peter Schauer

Institute of Archaeology, University College London,
Gower Street, London WC1E 6BT, United Kingdom

Volker Sommery

Department of Anthropology, University College London, Gower Street,
London WC1E 6BT, United Kingdom

Paul L. Vasey

Department of Psychology and Neuroscience, University of Lethbridge,
4401 University Drive, Lethbridge, Alberta, T1K 3M4, Canada

Hilde Vervaecke

University of Antwerp, Department of Biology, Universiteitsplein 1, B-2610
Wilrijk and Royal Zoological Society of Antwerp, Center of Research and
Conservation, K. Astridplein 26, B-2018 Antwerp and Bison Project,
Domaine de Bois St. Jean 7, 6982 Samré, Belgium

Brigitte Weiss

Konrad-Lorenz-Forschungsstelle für Ethologie, A-4645 Grünau 11, Austria

Dennis Werner

Depto. de Antropologia/CFH, Universidade Federal de Santa Catarina,
Campus Universitário, Florianópolis, Santa Catarina, 88.000, Brazil

Juichi Yamagiwa

Laboratory of Human Evolution Studies, Division of Biological Sciences,
Graduate School of Sciences, Kyoto University, Sakyo, Kyoto 606-8502, Japan

Akihiro Yamane

Kitakyushu Museum of Natural History and Human History, 2-4-1
Higashida, Kitakyushu 805-0071, Japan

Acknowledgements

    We wish to thank those colleagues who, as experts on certain taxonomic groups, reviewed individual chapters: Ruth Thomsen, Gerulf Reiger, Martha M. Robbins, Craig Stanford, Anne Storey and Lynne A. Fairbanks. Thanks are due to Alejandra Pascual Garrido for preparing the index.