Animal Signaling and Function

The diversity of animal signals has been widely documented, and the generality of animal signals also tantalizingly suggests that there are common mechanisms that have selected for their origin. However, while much progress has been made on some fronts, we still lack a general theory about why the diversity of signaling structures exist. Our compilation will directly address this gap by focusing on an exciting new arena of sexual selection, namely using functional approaches to understand signaling. This approach is rooted in the idea that many signals are designed to transmit important functional imformation that is both important for issues of male quality (and hence male competition), and female choice. The increasing use of technology in sexual selection studies has enabled researchers to test whether signaling is either constrained by, or accurately transmits information about functional capacities. Further, in animals that fight vigorously, functional capacities such as endurance or strength may make the difference between winning and losing. This volume brings together a diverse collection of researchers who are actively investigating how function and signaling are related. These researchers use both a variety of methods and taxa to study animal signaling, and we believe that this integrative view is important to open up fresh vistas for why animal signals have evolved.

Autorentext

Duncan J. Irschick, Ph.D. is an Assistant Professor in the Department of Biology at the University of Massachusetts at Amherst. His research interests are in the interface among organism design, function, and ecology. Broadly, he is interested in the evolution of complex functional systems in all its facets. His research integrates micro evolutionary and macro evolutionary approaches, and?applies both experimental and descriptive approaches to understand the causes of, and ultimately the consequences of, this diversity. Mark Briffa, Ph.D. is a Lecturer in Marine Biology at the University of Plymouth in the School of Biological Sciences. His main research focuses on contest behavior, where animals compete directly against one another over ownership of a limited resource. He is particularly interested in how animals use communication to resolve conflicts of interest this often involves 'repeated signals' that are?performed in a structured way. Jeffrey Podos, Ph.D. is an Associate Professor at the University of Massachusetts in the Biology Department. His research addresses the interface of animal behavior, organism biology, and evolutionary biology. His work focuses on vocal behavior and evolution in vertebrates, especially songbirds.

Inhalt
Contributors ix

1 INTRODUCTION 1
Duncan J. Irschick, Mark Briffa, and Jeffrey Podos

References 7

2 EARLY LIFE-HISTORY EFFECTS, OXIDATIVE STRESS, AND THE EVOLUTION AND EXPRESSION OF ANIMAL SIGNALS 11
Nick J. Royle, Josephine M. Orledge, and Jonathan D. Blount

Introduction 11

Signaling 12

Early Life-History Effects and Resource Allocation Trade-Offs 13

Oxidative Stress as a Mediator of Resource Allocation Trade-Offs 15

Signals Expressed During Development 20

Signals Expressed During Adulthood 25

Competition-Dependent Sexual Signals 32

Conclusions 34

Acknowledgments 36

References 36

3 A PERFORMANCE-BASED APPROACH TO STUDYING COSTS OF RELIABLE SIGNALS 47
Jerry F. Husak, Justin P. Henningsen, Bieke Vanhooydonck, and Duncan J. Irschick

Introduction 47

Receiver-Independent Costs 51

Receiver-Dependent Costs 55

Compensatory Traits 59

Conclusions 63

Acknowledgments 64

References 65

4 COGNITIVELY DRIVEN CO-OPTION AND THE EVOLUTION OF COMPLEX SEXUAL DISPLAYS IN BOWERBIRDS 75
Gerald Borgia and Jason Keagy

Introduction 75

Cognition, Co-Option, and Complex Display 78

Delayed Male Maturity, MaleMale Courtship, and Display Trait

Acquisition 81

Female Signaling to Affect Male Display Intensity: An Innovation that Improves Courtship Success 82

Mate Searching and Flexibility in Adaptive Decision-Making 83

Female Uncertainty and Flexibility in Active Mate Assessment 84

Long-Term Age-Related Improvement in Decoration Display: Symmetrical Decoration Displays on Older Males' Bowers 84

Anticipation of Male Routes during Courtship: Paths on Display Courts of Spotted Bowerbirds 86

Some Other Possible Cognitive Display-Related Behaviors of Bowerbirds 87

Construction of Successive Scenes for Females Visiting the Bower 88

Cognitive Aspects of Bower Building: Age-Related Improvement in Construction and Novel Techniques for Maintaining Symmetry 90

Cognitive Flexibility and Innovation in Display 93

Decoration Stealing: An Innovation for Display Trait Acquisition 94

Cooperating with Relatives for Display: An Innovation to Reduce

Sexual Competition 95

Vocal Mimicry: Learning and Innovation in Use of Co-Opted Displays 96

Co-Option Mechanism 98

Cognition in Display Trait Acquisition 100

References 101

5 INTEGRATING FUNCTIONAL AND EVOLUTIONARY APPROACHES TO THE STUDY OF COLOR-BASED ANIMAL SIGNALS 111
Darrell J. Kemp and Gregory F. Grether

Introduction 111

Color Signal Production in More Detail 115

Signals, Honesty, and Condition-Dependence 116

Coloration as an Honest Advertisement 117

Trinidadian Guppies (Poecilia Reticulata) 118

Pierid Butterflies (Subfamily Coliadinae) 122

Birds 127

Discussion/Conclusion/Future Work 129

Acknowledgments 131

References 131

6 AGONISTIC SIGNALS: INTEGRATING ANALYSIS OF FUNCTIONS AND MECHANISMS 141
Mark Briffa

Animal Contests and the Evolution of Agonistic Signals 141

Empirical Approaches to Testing Theory: Physiological Costs, Stamina, and Performance 154

Energy Status and Agonistic Signals 156

Whole Body Performance and Agonistic Signals 159

Conclusions 164

References 167

7 ACOUSTIC SIGNAL EVOLUTION: BIOMECHANICS, SIZE, AND PERFORMANCE 175
Jeffrey Podos and S.N. Patek

Introduction 175

Biomechanics 178

Body Size 183

Performance 187

Concluding Remarks 194

Acknowledgments 195

References 195 **8 DISHONEST SIGNALING DURING AGGRESSIVE INTERACTIONS: THEORY AND EMPIRICAL E...