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SOCIAL RECIPROCITY AND INTERCHANGE IN LONG-TAILED MACAQUES (MACACA FASCICULARIS) by MICHAEL DAVID GUMERT (Under the Direction of Irwin S. Bernstein) ABSTRACT Social grooming is a common and potentially valuable act for long-tailed macaques. It may be traded reciprocally or interchanged with other acts such as tolerance, sexual activity, and infant handling. Social exchange related to grooming may be contingent on specific acts of grooming, and thus traded, or it may just be a by-product of social relationships and thus not traded. If grooming can be traded, biological market theory predicts that grooming may be considered as “payment” for other social acts and would vary with supply and demand of available partners. If grooming is traded directly as payment for other social acts, specific acts of grooming should facilitate reciprocation and interchange. Also, the number of available partners (i.e. supply) should negatively influence grooming duration. In the first study, I analyzed sequences following grooming bouts to test the hypothesis that reciprocation and interchange can be linked to specific acts of grooming. I found that specific acts of grooming facilitated subsequent reciprocation and interchange with tolerance or sexual activity. In the second study, I investigated exchange patterns of female-to-mother with infant grooming and its relation to the supply of infants. I found that after mothers with infants received grooming from a female, infant contact by the grooming female was facilitated. I also found a negative relationship between grooming bout duration and the number of infants per female surrounding female-to-mother grooming bouts associated with infant handling. It seemed that grooming did facilitate infant handling and that grooming duration was negatively related to infant supply. In the third study, I investigated whether there was a relationship between grooming duration and the supply of females around male-to-female grooming bouts associated with mating. I found a negative relationship between bout duration and the number of females per male surrounding a mating- related grooming. From these studies, I concluded that specific acts of grooming can facilitate reciprocation and interchange and that the supply of partners is related to the amount of grooming payment an individual will offer to their partner. Overall, some grooming exchanges appear to occur as trades, where grooming is “payment” for other social acts such as more grooming, tolerance, sexual activity/mating, and infant handling. INDEX WORDS: Macaca fascicularis, Long-tailed macaque, Grooming, Tolerance, Sex, Mating, Infant handling, Reciprocity, Interchange, Biological market theory SOCIAL RECIPROCITY AND INTERCHANGE IN LONG-TAILED MACAQUES (MACACA FASCICULARIS) by MICHAEL DAVID GUMERT B.S., East Stroudsburg University, 1997 M.S., Bucknell University, 2001 A Dissertation Submitted to the Graduate Faculty of The University of Georgia in Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY ATHENS, GEORGIA 2006 © 2006 Michael David Gumert All Rights Reserved SOCIAL RECIPROCITY AND INTERCHANGE IN LONG-TAILED MACAQUES (MACACA FASCICULARIS) by MICHAEL DAVID GUMERT Major Professor: Irwin Bernstein Committee: Dorothy Fragaszy Phillip Holmes Carolyn Ehardt Electronic Version Approved: Maureen Grasso Dean of the Graduate School The University of Georgia May 2006 iv ACKNOWLEDGEMENTS This research project was supported by a Fulbright Graduate Research Fellowship from the American-Indonesian Exchange Foundation (AMINEF), Jakarta, Indonesia. I would like to thank AMINEF for all of their assistance during my stay in Indonesia – especially Nelly Paliama. I thank the Indonesian Institute of Sciences (LIPI) for providing me with a research permit to conduct research in Indonesia. I am grateful to the Indonesian Department of Forestry for granting me permission to enter Tanjung Puting National Park and to reside in the park area during my research. I would also like to express a deep thanks to Dr. Noviar Andayani from the Faculty of Mathematics and Natural Sciences at the University of Indonesia for sponsoring my work and assisting in attaining all of my permits. I give special thanks to my advisor Irwin S. Bernstein for all his assistance in formulating ideas and writing up this research. His critical advice was invaluable to the completion of this work. I would also like to thank my other committee members, Dorothy Fragaszy, Carolyn Ehardt, and Phillip Holmes for their help and assistance in completing this dissertation. I give special thanks to my research assistant, Peltanadanson, for his tireless efforts in the field and for being a good friend. I express my gratitude to the management and staff of Rimba Orangutan Ecolodge for their support and my housing during the research project. I also thank Pak Yatno and the Baso family for their support, help, and always providing a place to stay in Kumai during my long stay in Kalimantan. I give special thanks to Bagus Setiawan and Jogi Ardana, who are always an invaluable help whenever I stay in Indonesia. v In addition to the people that assisted me during my research, I give a very special thanks to the Rimba macaques. Without them, none of this work would have been possible. Having been given the chance to take a short glimpse into their interesting lives, I feel mine has been forever changed. I would like to dedicate this work to them. Last but not least, I would like to especially thank my parents and family for their support during my graduate school career. Without their support and encouragement none of this would have been possible. Thank you so much for your love and support during all of this. vi TABLE OF CONTENTS Page ACKNOWLEDGEMENTS........................................................................................................... iv LIST OF FIGURES ...................................................................................................................... vii CHAPTER 1 INTRODUCTION AND LITERATURE REVIEW .....................................................1 2 SEQUENTIAL GROOMING RECIPROCITY AND INTERCHANGE IN WILD LONG-TAILED MACAQUES, (MACACA FASCICULARIS) ................................7 3 GROOMING AND INFANT HANDLING INTERCHANGE IN LONG-TAILED MACAQUES (MACACA FASCICULARIS): THE RELATIONSHIP BETWEEN INFANT SUPPLY AND GROOMING PAYMENT. ............................................42 4 THE RELATIONSHIP BETWEEN SUPPLY OF FEMALES AND MALE-TO- FEMALE MATING-RELATED GROOMING BOUT DURATION....................60 5 GENERAL DISCUSSION AND CONCLUSIONS....................................................73 REFERENCES ..............................................................................................................................76 APPENDICES ...............................................................................................................................80 A INTRODUCTION TO BIOLOGICAL MARKETS ...................................................81 B SUPPORT FOR BIOLOGICAL MARKETS IN PRIMATES....................................88 C ATTITUDINAL RECIPROCITY: A PROXIMATE EXPLANATION FOR SOCIAL TRADE....................................................................................................................95 C EXPERIMENTAL WORK ON RECIPROCITY AND INTERCHANGE...............102 vii LIST OF FIGURES Page Figure 2.1:......................................................................................................................................34 Figure 2.2:......................................................................................................................................35 Figure 2.3:......................................................................................................................................36 Figure 2.4:......................................................................................................................................37 Figure 2.5:......................................................................................................................................38 Figure 2.6:......................................................................................................................................39 Figure 2.7:......................................................................................................................................40 Figure 2.8:......................................................................................................................................41 Figure 3.1:......................................................................................................................................58 Figure 3.2:......................................................................................................................................59 Figure 4.1:......................................................................................................................................72 1 CHAPTER 1 INTRODUCTION AND LITERATURE REVIEW Grooming has many potential functions in primates. It has the utilitarian function of maintenance and hygiene by removing particles and potential parasites from the pelage of the receiving animal (Freeland, 1976; Hutchins & Barash, 1976; Barton, 1985; Saunders, 1988; Tanaka & Takefushi, 1993). Grooming reduces tension (Sparks, 1967; Schino et al., 1988) and can be used as an act of reconciliation (Aureli & van Schaik, 1991; Aureli, et al., 1992; Aureli & de Waal, 2000). Based on physiological responses
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