APPLICATIONS OF SIGNALING THEORY TO CONTEMPORARY HUMAN COURTSHIP By BRIA LANE DUNHAM A Dissertation submitted to the Graduate School—New Brunswick Rutgers, the State University of New Jersey in partial fulfillment of the requirements for the degree of Doctor of Philosophy Graduate Program in Anthropology written under the direction of Lee Cronk and approved by ______________________________________________ ______________________________________________ ______________________________________________ ______________________________________________ New Brunswick, NJ October, 2010 © 2010 Bria Lane Dunham ALL RIGHTS RESERVED ABSTRACT OF THE DISSERTATION Applications of Signaling Theory to Contemporary Human Courtship By BRIA LANE DUNHAM Dissertation Director: Lee Cronk, Ph.D. Signaling theory, a popular approach in ethology and theoretical biology, can be employed to better understand social interaction in humans. Applied to contemporary human courtship, signaling theory can provide a framework for interpreting information transmitted at an initial encounter, signals conveyed at key relationship phases both within a romantic couple and to outside parties, and the regular communicative exchange within established relationships. This dissertation applies signaling theory to courtship in testing evolutionary hypotheses within three projects, each involving a different subject population situated at a salient courtship phase. The first project addresses the signaling value of women's faces absent any other information, which is analogous to a first meeting prior to the beginning of courtship. Testosterone-mediated facial features were positively associated with viewer perceptions of masculinity, positively associated with ii self-reports of sociosexual attitudes and behaviors, and negatively associated with viewer perceptions of attractiveness. The second project explores the signaling potential of engagement rings among a sample of Ohio newlyweds. Engagement ring cost was positively associated with male income and female income, and was negatively associated with female age, indicating that engagement ring cost may reflect both male and female mate value. The cost of engagement rings as a proportion of male salary was positively associated with courtship duration, suggesting that engagement ring cost may reinforce a signal of commitment already conveyed by a lengthy courtship. The third project concerns notions of spousal obligation on the Honduran island of Utila. This project used an experimental interview setting to elicit and measure audience effects. In response to key questions about characteristics sought in wives, men interviewed in the presence of their wives used more forceful rhetoric. Furthermore, men's responses more frequently emphasized women's morality whereas women's responses more frequently emphasized male resource control. iii ACKNOWLEDGEMENTS I owe a tremendous debt to Lee Cronk for his steadfast support, guidance, and friendship over the past nine years. He has been a tremendous source of information and inspiration, having introduced me to the theoretical approach of signaling theory as well as to the key principles of and figures within human behavioral ecology. He has been a fantastic collaborator within our shared research and highly supportive of projects that I have undertaken on my own. I could not have asked for a more responsive, accessible, and committed Dissertation Chair. His boundless patience has seen me through many revisions and this dissertation would not have been possible without him. I also wish to express my gratitude to the members of my committee: Ryne Palombit, Laura Ahearn, and Helen Fisher. Their perspectives and support over the course of my graduate training have been invaluable. Robert Trivers supervised one of my field statements and participated in my dissertation proposal defense. Chi-hua Chiu also participated in my dissertation proposal defense. I have greatly benefitted from the support of such talented scholars through my studies and appreciate the time they have invested in my career. My family and friends have been wonderfully supportive and encouraging throughout my time at Rutgers. I wish to especially thank my husband, Mark Murphy, for his understanding on all the long nights I spent writing, from my field statements to the final revisions of this dissertation. I also wish to thank Jennifer Trivedi for giving me feedback and a fresh perspective on chapter drafts and assorted projects over the years. The members of the Human Behavioral Ecology Lab at Rutgers University have been a iv stimulating source of new ideas, connections, and applications through both our formal discussion sessions and casual interactions, and I am grateful to all of them for the role they have had in shaping my intellectual development. Portions of this research were previously published as Cronk and Dunham (2007), “Amounts spent on engagement rings reflect aspects of male and female mate quality” in Human Nature, and Campbell et al. (2009), “The association between men’s ratings of women as desirable long-term mates and individual differences in women’s sexual attitudes and behaviors” in Personality and Individual Differences. Research resulting from the same field season as was used in Chapter 4 of this dissertation was previously published in Cronk and Steadman (2002) and Cronk et al. (2009), both of which were highly instructive for my work. I owe gratitude to my collaborators on these projects: Lee Cronk, Shannon Steadman, Lorne Campbell, Jeffry Simpson, Alison Milroy, and Carol Wilson. I am further thankful to William Irons, Tara Wigington, and Amy Jacobson for their contributions to companion projects to the Utilian and facial features research used in this dissertation. Concurrently with writing my dissertation, I was involved in the writing of two review articles: Kimmeldorf et al., “Gift-giving as signaling,” which is currently in revision; and Dunham, “The role for signaling theory and receiver psychology in marketing,” which is forthcoming in Evolutionary Psychology in the Business Sciences with Springer. I feel that this dissertation has profited from these works and wish to thank my collaborators for the former article, Marcia Kimmeldorf and Michael McCullough, as well as my editor for the latter chapter, Gad Saad, for their work and feedback. I also wish to thank Will Brown, Drew Gerkey, and Marie Diener-West for fruitful advice they gave me regarding analytical techniques for v projects within my dissertation. Most importantly, I wish to thank the college students, Ohioan newlyweds, and Utilian men and women who volunteered their time and their information for these projects. I could not have constructed this dissertation without their data and I very much appreciate their generosity to my collaborators and me. Financial support for my involvement in this research included a Bigel grant and a grant from the Center for Human Evolutionary Studies (CHES). Support awarded to my collaborators for this work included funds from the Social Sciences and Humanitites Research Council of Canada, Premier’s Research Council Excellence Awards, additional support from CHES, the Research Council and Department of Anthropology at Rutgers University, and Texas A & M University. I am further grateful to research assistants who contributed to data collection, transcription, and coding. vi DEDICATION To my mother, for supporting my obstinately tenacious goal to become an evolutionary anthropologist ever since I asked her to read Lucy to me when I was seven years old. And to Elliott, whose intellectual and creative passions I hope to one day support just as faithfully. vii TABLE OF CONTENTS Title Page..............................................................................................................................i Abstract................................................................................................................................ii Acknowledgements.............................................................................................................iv Dedication..........................................................................................................................vii Table of Contents..............................................................................................................viii List of Tables and Figures.................................................................................................xii CHAPTER ONE: INTRODUCTION 1. Courtship Signaling............................................................................................1 2. A Short Primer on Signaling Theory..................................................................2 2.1 Signal Design Principles.......................................................................5 2.2 Cues.......................................................................................................7 2.3 Signal Costs..........................................................................................8 2.4 Receiver Psychology...........................................................................11 2.5 Signal Forms.......................................................................................13 3. Sexual Selection Theory...................................................................................18 4. Courtship Signaling in Humans........................................................................23 5. Courtship Dynamics..........................................................................................27