Marine Mammals (eBook)

Evolutionary Biology

Annalisa Berta, Kit M. Kovacs, James L. Sumich (Autoren)

eBook Download: EPUB

2005 | 2. Auflage
560 Seiten
Elsevier Science (Verlag)
978-0-08-048934-6 (ISBN)

Infos

Berta and Sumich have succeeded yet again in creating superior marine reading! This book is a succinct yet comprehensive text devoted to the systematics, evolution, morphology, ecology, physiology, and behavior of marine mammals. The first edition, considered the leading text in the field, is required reading for all marine biologists concerned with marine mammals. Revisions include updates of citations, expansion of nearly every chapter and full color photographs. This title continues the tradition by fully expanding and updating nearly all chapters.

* Comprehensive, up-to-date coverage of the biology of all marine mammals
* Provides a phylogenetic framework that integrates phylogeny with behavior and ecology
* Features chapter summaries, further readings, an appendix, glossary and an extensive bibliography
* Exciting new color photographs and additional distribution maps

Inhalt

Front Cover 1
Marine Mammals: Evolutionary Biology 4
Copyright Page 5
CONTENTS 6
Preface 10
Acknowledgments 11
Chapter 1. Introduction 12
1.1. Marine Mammals—“What Are They?” 12
1.2. Adaptations for Aquatic Life 12
1.3. Scope and Use of This Book 13
1.4. Time Scale 13
1.5. Early Observations of Marine Mammals 14
1.6. Emergence of Marine Mammal Science 18
1.7. Further Reading and Resources 20
References 20
PART I: Evolutionary History 23
Chapter 2. Systematics and Classification 23
2.1. Introduction: Systematics—What Is It and Why Do It? 23
2.2. Some Basic Terminology and Concepts 24
2.3. How Do You Do Cladistics? 28
2.4. Testing Phylogenetic Hypotheses 30
2.5. Going Beyond the Phylogenetic Framework: Elucidating Evolutionary and Ecological Patterns 32
2.6. Taxonomy and Classification 33
2.7. Summary and Conclusions 35
2.8. Further Reading 35
References 35
Chapter 3. Pinniped Evolution and Systematics 38
3.1. Introduction 38
3.2. Origin and Evolution 38
3.3. Summary and Conclusions 57
3.4. Further Reading 58
References 58
Chapter 4. Cetacean Evolution and Systematics 62
4.1. Introduction 62
4.2. Origin and Evolution 62
4.3. Summary and Conclusions 92
4.4. Further Reading 92
References 93
Chapter 5. Sirenians and Other Marine Mammals: Evolution and Systematics 100
5.1. Introduction 100
5.2. Origin and Evolution of Sirenians 100
5.3. The Extinct Sirenian Relatives—Desmostylia 109
5.4. The Extinct Marine Bear-Like Carnivoran, Kolponomos 111
5.5. The Extinct Aquatic Sloth, Thalassocnus natans 113
5.6. The Sea Otter, Enhydra lutris 113
5.7. The Polar Bear, Ursus maritimus 116
5.8. Summary and Conclusions 116
5.9. Further Reading 118
References 118
Chapter 6. Evolutionary Biogeography 122
6.1. Introduction—What Is Biogeography and Why Is It Important? 122
6.2. Ecological Factors Affecting Distributions of Marine Mammals 122
6.3. Present Patterns of Distribution 128
6.4. Reconstructing Biogeographic Patterns 130
6.5. Past Patterns of Distribution 132
6.6. Summary and Conclusions 138
6.7. Further Reading and Resources 139
References 140
PART II: Evolutionary Biology, Ecology, And Behavior 143
Chapter 7. Integumentary and Sensory Systems 143
7.1. Introduction 143
7.2. Integumentary System 143
7.3. Nerves and Sense Organs 159
7.4. Summary and Conclusions 167
7.5. Further Reading 168
References 168
Chapter 8. Musculoskeletal System and Locomotion 176
8.1. Introduction 176
8.2. Pinnipeds 176
8.3. Cetaceans 189
8.4. Sirenians 206
8.5. Sea Otter 211
8.6. Polar Bear 214
8.7. Summary and Conclusions 214
8.8. Further Reading 216
References 217
Chapter 9. Energetics 224
9.1. Introduction 224
9.2. Metabolic Rates 224
9.3. Thermoregulation 228
9.4. Energetics of Locomotion 234
9.5. Osmoregulation 240
9.6. Summary and Conclusions 242
9.7. Further Reading 243
References 243
Chapter 10. Respiration and Diving Physiology 248
10.1. Introduction 248
10.2. Problems of Deep and Prolonged Dives for Breath-Holders 248
10.3. Pulmonary and Circulatory Adaptations to Diving 250
10.4. Diving Response 263
10.5. Diving Behavior and Phylogenetic Patterns 265
10.6. Summary and Conclusions 273
10.7. Further Reading 273
References 273
Chapter 11. Sound Production for Communication, Echolocation, and Prey Capture 281
11.1. Introduction 281
11.2. Sound Propagation in Air and Water 281
11.3. Anatomy and Physiology of Sound Production and Reception 283
11.4. Functions of Intentionally Produced Sounds 295
11.5. Acoustic Thermometry of Ocean Climate and Low-Frequency Military Sonars 313
11.6. Summary and Conclusions 314
11.7. Further Reading 315
References 316
Chapter 12. Diet, Foraging Structures, and Strategies 323
12.1. Introduction 323
12.2. Seasonal and Geographical Patterns of Prey Abundance 324
12.3. Adaptations for Foraging in Pinnipeds 325
12.4. Feeding Specializations of Cetaceans 335
12.5. Feeding Specializations of Sirenians 355
12.6. Feeding Specializations of Other Marine Mammals 361
12.7. Summary and Conclusions 365
12.8. Further Reading 366
References 366
Chapter 13. Reproductive Structures, Strategies, and Patterns 374
13.1. Introduction 374
13.2. Anatomy and Physiology of the Reproductive System 376
13.3. Mating Systems 388
13.4. Lactation Strategies 406
13.5. Reproductive Patterns 413
13.6. Summary and Conclusions 416
13.7. Further Reading 417
References 418
Chapter 14. Population Structure and Dynamics 427
14.1. Introduction 427
14.2. Abundance and Its Determination in Marine Mammals 428
14.3. Techniques for Monitoring Populations 430
14.4. Population Structure and Dynamics 443
14.5. Summary and Conclusions 455
14.6. Further Reading 456
References 456
Chapter 15. Exploitation and Conservation 467
15.1. Introduction 467
15.2. Commercial Exploitation of Marine Mammals 467
15.3. Legal Framework for Marine Mammal Conservation and Protection 471
15.4. Incidental Taking of Marine Mammals 477
15.5. Environmental Contaminants 483
15.6. Single Beachings vs Mass Strandings 486
15.7. Ecotourism 489
15.8. Progress and the Future 491
15.9. Summary and Conclusions 494
15.10. Further Reading 494
References 495
Appendix: Classification of Marine Mammals 502
Glossary 524
Index 532

Textauszug

2 Systematics and Classification

2.1. Introduction: Systematics—What Is It and Why Do It?

Systematics is the study of biological diversity that has as its emphasis on the reconstruction of phylogeny, the evolutionary history of a particular group of organisms (e.g., species). Systematic knowledge provides a framework for interpreting biological diversity. Because it does this in an evolutionary context it is possible to examine the ways in which attributes of organisms change over time, the direction in which attributes change, the relative frequency with which they change, and whether change in one attribute is correlated with change in another. It also is possible to compare the descendants of a single ancestor to look for patterns of origin and extinction or relative size and diversity of these groups. Systematics also can be used to test hypotheses of adaptation. For example, consider the evolution of the ability to hear high frequency sounds, or echolocation, in toothed whales. One hypothesis for how toothed whales developed echolocation suggests that the lower jaw evolved as a unique pathway for the transmission of high frequency sounds under water. However, based on a study of the hearing apparatus of archaic whales, Thewissen et al. (1996) proposed that the lower jaw of toothed whales may have arisen for a different function, that of transmitting low frequency sounds from the ground, as do several vertebrates including the mole rat. According to this hypothesis, the lower jaw became specialized later for hearing high frequency sound. In this way the lower jaw of toothed whales may be an exaptation for hearing high frequency sounds. An exaptation is defined as any adaptation that performs a function different from the function that it originally held. A more complete understanding of the evolution of echolocation requires examination of other characters involved such as the presence of a melon and the morphology of the middle ear and jaw as well as the bony connections between the ear and skull (see Chapter 11).

An understanding of the evolutionary relationships among species can also assist in identifying priorities for conservation (Brooks et al., 1992). For example, the argument for the conservation priority of sperm whales is strengthened by knowing that this lineage occupies a key phylogenetic position as basal relative to the other species of toothed whales. These pivotal species are of particular importance in providing baseline comparative data for understanding the evolutionary history of the other species of toothed whales. Sperm whales provide information on the origin of various morphological characters that permit suction feeding and the adaptive role of these features in the early evolution of toothed whales.

Perhaps most importantly, systematics predicts properties of organisms. For example, as discussed by Promislow (1996), it has been noted that some toothed whales (e.g., pilot whales and killer whales) that have extended parental care also show signs of reproductive aging (i.e., pregnancy rates decline with increasing age of females), whereas baleen whales (e.g., fin whales) demonstrate neither extended parental care nor reproductive aging (Marsh and Kasuya, 1986). Systematics predicts that these patterns would hold more generally among other whales and that we should expect other toothed whales to show reproductive aging.

Finally, systematics also provides a useful foundation from which to study other biological patterns and processes. Examples of such studies include the coevolution of pinniped parasites and their hosts (Hoberg, 1992, 1995), evolution of locomotion and feeding in pinnipeds (Berta and Adam, 2001; Adam and Berta, 2002), evolution of body size in phocids (Wyss, 1994), evolution of phocid breeding patterns (Perry et al., 1995) and pinniped recognition behavior (Insley et al., 2003), and the evolution of hearing in whales (Nummela et al., 2004). Male social behavior among cetaceans was studied using a phylogenetic approach (Lusseau, 2003), and Kaliszewska et al. (2005) explored the population structure of right whales, based on genetic studies of lice that live in association with these whales.

2.2. Some Basic Terminology and Concepts

The discovery and description of species and the recognition of patterns of relationships among them is founded on the concept of evolution. Patterns of relationships among species are based on changes in the features or characters of an organism. Characters are diverse, heritable attributes of organisms that include DNA base pairs, anatomical and physiological features, and behavioral traits. Two or more forms of a given character are termed the character states. For example, the character “locomotor pattern” might consist of the states “alternate paddling of the four limbs (quadrupedal paddling),” “paddling by the hind limbs only (pelvic paddling),” “lateral undulations of the vertebral column and hind limb (caudal undulation),” and “vertical movements of the tail (caudal oscillation).” Evolution of a character may be recognized as a change from a preexisting, or ancestral (also referred to as plesiomorphic or primitive), character state to a new derived (also referred to as apomorphic) character state. For example, in the evolution of locomotor patterns in cetaceans, the pattern hypothesized for the earliest whales is one in which they swam by paddling with the hind limbs. Later diverging whales modified this feature and show two derived conditions: (1) lateral undulations of the vertebral column and hind limbs and (2) vertical movements of the tail.

The basic tenet of phylogenetic systematics, or cladistics (from the Greek word meaning “branch”), is that shared derived character states constitute evidence that the species possessing these features share a common ancestry. In other words, the shared derived features or synapomorphies represent unique evolutionary events that may be used to link two or more species together in a common evolutionary history. Thus, by sequentially linking species together based on their common possession of synapomorphies, the evolutionary history of those taxa (named groups of organisms) can be inferred.

Relationships among taxonomic groups (e.g., species) are commonly represented in the form of a cladogram, or phylogenetic tree, a branching diagram that conceptually represents the best estimate of phylogeny (Figure 2.1). The lines or branches of the cladogram are known as lineages or clades. Lineages represent the sequence of ancestor-descendant populations through time. Branching of the lineages at nodes on the cladogram represents speciation events, a splitting of a lineage resulting in the formation of two species from one common ancestor. Trees can be drawn to display the branching pattern only or in the case of molecular phylogenetic trees drawn with proportional branch lengths that correspond to the amount of evolution (approximate percentage sequence divergence) between the two nodes they connect.

The task in inferring a phylogeny for a group of organisms is to determine which characters are derived and which are ancestral. If the ancestral condition of a character or character state is established, then the direction of evolution, from ancestral to derived, can be inferred, and synapomorphies can be recognized. The methodology for inferring direction of character evolution is critical to cladistic analysis. Outgroup comparison is the most widely used procedure. It relies on the argument that a character state found in close relatives of a group (the outgroup) is likely also to be the ancestral or primitive state for the group of organisms in question (the ingroup). Usually more than one outgroup is used in an analysis, the most important being the first or genealogically closest outgroup to the ingroup, called the sister group. In many cases, the primitive state for a taxon can be ambiguous. The primitive state can only be determined if the primitive states for the nearest outgroup are easy to identify and those states are the same for at least the two nearest outgroups (Maddison et al., 1984).

Using the previous example, determination of the primitive cetacean locomotor pattern is based on its similarity to that of an extinct relative to the cetaceans, a group of four legged mammals known as the mesonychids (i.e., an outgroup), which are thought to have swam by quadrupedal paddling. Locomotion in whales went through several stages. Ancestral whales (i.e., Ambulocetus) swam by pelvic paddling propelled by the hind limbs only. Later diverging whales (i.e., Kutchicetus) went through a caudal undulation stage propelled by the feet and tail. Finally, extinct dorudontid cetaceans and modern whales adopted caudal oscillation using vertical movements of the tail as their swimming mode (Figure 2.2; Fish, 1993).

Figure 2.1. A cladogram illustrating general terms discussed in the text.

Derived characters are used to link monophyletic groups, groups of taxa that consist of a common...

Produkt-Details

• Erscheint lt. Verlag: 14.12.2005
• Sprache: englisch
• Themenwelt: Sachbuch/Ratgeber
• Themenwelt: Kinder- / Jugendbuch ► Jugendbücher ab 12 Jahre
• Themenwelt: Kinder- / Jugendbuch ► Sachbücher
• Themenwelt: Schulbuch / Wörterbuch
• Themenwelt: Naturwissenschaften ► Biologie ► Evolution
• Themenwelt: Naturwissenschaften ► Biologie ► Limnologie / Meeresbiologie
• Themenwelt: Naturwissenschaften ► Biologie ► Ökologie / Naturschutz
• Themenwelt: Naturwissenschaften ► Biologie ► Zoologie
• Themenwelt: Naturwissenschaften ► Geowissenschaften
• Themenwelt: Technik
• Themenwelt: Weitere Fachgebiete ► Land- / Forstwirtschaft / Fischerei
• ISBN-10: 0-08-048934-6 / 0080489346
• ISBN-13: 978-0-08-048934-6 / 9780080489346