Scaling: Why Is Animal Size So Important?

Galileo wrote that andldquo;nature cannot produce a horse as large as twenty ordinary horses or a giant ten times taller than an ordinary man unless by miracle or by greatly altering the proportions of his limbs and especially of his bonesandrdquo;andmdash;a statement that wonderfully captures a long-standing scientific fascination with body size. Why are organisms the size that they are? And what determines their optimum size?and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;and#160;This volume explores animal body size from a macroecological perspective, examining species, populations, and other large groups of animals in order to uncover the patterns and causal mechanisms of body size throughout time and across the globe. The chapters represent diverse scientific perspectives and are divided into two sections. The first includes chapters on insects, snails, birds, bats, and terrestrial mammals and discusses the body size patterns of these various organisms. The second examines some of the factors behind, and consequences of, body size patterns and includes chapters on community assembly, body mass distribution, life history, and the influence of flight on body size.

"...a must for teachers who like to add thought-provoking material to lectures or class discussions." The Science Teacher

andldquo;It is not a comprehensive discussion of body size in animals but ratherandmdash;as suggested by the title after the colonandmdash;focuses on why animals are the sizes that they are based on a comparative macroecological perspective. . . . The editorsandrsquo; own chapter on size in mammals through space and time is an important contribution to the field. . . . Animal Body Size includes a range of papers that would likely be of interest to ecologists, paleontologists, and conservation biologists.andrdquo;

and#8220;Although the contributors are numerous and the topic large, several threads running through this collection make it strongly cohesive. . . . Animal Body Size provides a landmark, or point of reference, in the progress toward understanding body size, its implications, and its consequences.and#8221;

andldquo;This diverse collection provides a fascinating glimpse into a fundamental property of animal communities: the distribution of body sizes. With a stimulating integration of ecology and paleobiology that addresses the interplay of structure, function, the environment, and evolutionary history, this compilation is sure to appeal to a broad readership. By bringing to the forefront a suite of unanswered questions, the contributorsandrsquo; efforts will motivate exciting new research into how communities are structured across space and through time.andrdquo;

andldquo;Felisa A. Smith, S. Kathleen Lyons, and a cadre of leaders and pioneers in their field present a comprehensive yet imminently accessible synthesis that successfully argues that size matters in more ways than we could have possibly imagined.andrdquo;

andldquo;Animal Body Size presents macroecological patterns in body size distributions for vertebrates and invertebrates and evaluations of ecological and evolutionary processes that shape body size distributions of clades and communities. Contributors emphasize patterns and processes at different taxonomic and spatial scales. Recurrent themes include life history analysis, metabolic scaling, allometry, ecogeographic and evolutionary trends in body size, ecological interactions, and biogeography. The strengths of this book lie in its broad vision of body size research, the intertwined ecological and evolutionary perspectives, and excellent bibliographies. The book will be useful as both a reference and a stimulus to new avenues of research.andrdquo;

This book is about the importance of animal size.

This short, non-mathematical discussion of how the physical size of an animal affects its physiological functions can be read profitably by both students and professional scientists. Elegantly written, the book illuminates those physical laws controlling rates of diffusion and heat transfer, transfer of force and momentum, the strength of structures, the dynamics of locomotion, and so on. It shows how these laws have profound implications for animals of widely different size and scale and why the size of living things is of such fundamental importance.

This book is about the importance of animal size. We tend to think of animal function in chemical terms and talk of water, salts, proteins, enzymes, oxygen, energy, and so on. We should not forget, however, that physical laws are equally important, for they determine rates of diffusion and heat transfer, transfer of force and momentum, the strength of structures, the dynamics of locomotion, and other aspects of the functioning of animal bodies. Physical laws provide possibilities and opportunities for an organism, yet they also impose constraints, setting limits to what is physically possible. This book aims to give an understanding of these rules because of their profound implications when we deal with animals of widely different size and scale. The reader will find that the book raises many questions. Remarkable and puzzling information makes it read a little like a detective story, but the last chapter, instead of giving the final solution, neither answers all questions nor provides one great unifying principle.

Felisa A. Smith is professor of biology at the University of New Mexico and lives in Santa Fe, NM.

S. Kathleen Lyons is a research scientist in the Department of Paleobiology at the National Museum of Natural History and lives in Arlington, VA.

Preface

Acknowledgments

Introduction: On Being the Right Size: The Importance of Size in Life History, Ecology and Evolution

Felisa A. Smith and S. Kathleen Lyons

PART I. Body Size Patterns across Space and Time

CHAPTER 1. Macroecological Patterns in Insect Body Size

Kevin J. Gaston and Steven L. ChownCHAPTER 2. Latitudinal Variation of Body Size in Land Snail Populations and Communities

Jeffrey C. Nekola, Gary M. Barker, Robert A. D. Cameron, and Beata M. PokryszkoCHAPTER 3. Geographic Variation in Body Size Distributions of Continental Avifauna

Brian A. MaurerCHAPTER 4. Evolution of Body Size in Bats

Kamran Safi, Shai Meiri, and Kate E. JonesCHAPTER 5. Macroecological Patterns of Body Size in Mammals across Time and Space

S. Kathleen Lyons and Felisa A. Smith

PART II. Mechanisms and Consequences Underlying Body Size Distributional Patterns

CHAPTER 6. Using Size Distributions to Understand the Role of Body Size In Mammalian Community Assembly

S. K. Morgan ErnestCHAPTER 7. Processes Responsible for Patterns in Body Mass Distribution

Brian A. Maurer and Pablo A. MarquetCHAPTER 8. The Influence of Flight on Patterns of Body Size Diversity and Heritability

Felisa A. Smith, S. Kathleen Lyons, Kate E. Jones, Brian A. Maurer, and James H. BrownCHAPTER 9. On Body Size and Life History of Mammals

James H. Brown, Astrid Kodric-Brown, and Richard M. SiblyConclusion: The Way Forward

Felisa A. Smith and S. Kathleen Lyons

List of Contributors

Index