Subterranean Rodents (eBook)

Contents 7
Introduction 17
Subterranean Rodents: News from Underground 18
References 24
Part I Ecophysiology 25
Adaptive Physiological Mechanisms in the Underground Dwellers 26
2.1 Energy and Material Fluxes 27
2.2 Neural and Hormonal Regulation 29
References 30
Microclimate in Burrows of Subterranean Rodents – Revisited 33
3.1 Introduction 33
3.2 Microenvironmental Parameters 34
3.3 Further Perspectives 42
References 43
New Data onMetabolic Parameters in Subterranean Rodents 46
4.1 Introduction 46
4.2 Variation of Basal Metabolic Rate on Interspecific Level 47
4.3 Variation of Resting Metabolic Rate on Intraspecific Level 52
References 55
Skimping as an Adaptive Strategy in Social Fossorial Rodents: The Mole Vole ( Ellobius talpinus) as an Example 59
5.1 Introduction 59
5.2 Subjects, Area and Methodological Comments 60
5.3 Standard Metabolic Rate, Cost of Locomotion and Thermoregulation 61
5.4 Growth and Reproduction 62
5.5 Immune Defense 65
5.6 Adrenocortical Response to Stress 66
5.7 Conclusion 67
References 68
The Reproductive Physiology and Endocrinology of the African Mole-rats: with Special Reference to Southern African Mole-rat Species 71
6.1 Introduction 71
6.2 Reproductive Strategies in Solitary and Social African Mole- rats 72
6.3 Seasonal Breeding in Social Mole-rats 79
6.4 Induced vs Spontaneous Ovulation and the Role of Penile Ornamentation 80
6.5 Habitat Shapes the Reproductive Physiology of African Mole- rats 81
6.6 Monopolization of Reproduction: Plural Breeding in Males and Females 82
6.7 Perspective 83
References 84
Part II Sensory Ecology 89
Sensory Ecology of Subterranean Rodents 90
References 92
Using Odors Underground 94
8.1 Introduction 94
8.2 Foraging Underground 95
8.3 Recognizing and Discriminating Between Conspecifics Underground 96
8.4 Conclusion 103
References 103
Acoustics, Audition and Auditory System 106
9.1 Introduction 106
9.2 Acoustics in Burrows 107
9.3 Hearing in Subterranean Rodents 108
9.4 Morphological Adaptations of the Ear 112
9.5 Synthesis 117
References 118
Acoustic Communication in Subterranean Rodents 121
10.1 Introduction 121
10.2 Adult Vocalizations 122
10.3 Juvenile Vocalizations: Are Care-elicitation Calls Honest Advertisements of Offspring Need? 131
10.4 Conclusion 133
References 133
Visual Systems and the Role of Vision in Subterranean Rodents: Diversity of Retinal Properties and Visual System Designs 136
11.1 Introduction 136
11.2 EyeMorphology 136
11.3 Retina 137
11.4 Optic Nerve (ON) 146
11.5 Subcortical Visual System 148
11.6 Visual Cortex 157
11.7 Oculomotor Nuclei 159
11.8 Role of Vision 159
11.9 Chronobiology 161
References 162
Magnetic Compass: A Useful Tool Underground 168
12.1 Introduction 168
12.2 Available Information: From Earth to Animal 169
12.3 Compass Mode: From Behavioural Experiment to Proof 170
12.4 Transduction Mechanisms: From Signal to Receptor 173
12.5 Neuronal Processing: From Receptor to Brain 176
References 177
Adaptive Neural Organization of Naked Mole- Rat Somatosensation ( and Those Similarly Challenged) 182
13.1 Introduction 182
13.2 Naked Mole-rat Body Hairs 182
13.3 Somatosensation and Behavior 184
13.4 Somatosensory Specializations in the Central Nervous Systemof Naked Mole-rats 190
13.5 Comparisons to Star-Nosed Moles 193
13.6 New Directions: Unique Somatic Organization for Processing Painful Stimuli 195
13.7 Conclusion 197
References 198
Part III Life Histories, Behavioural Ecology, Demography 201
From Natural Histories to Life Histories – A Homage to a Comparative Approach 202
How and Where to Go from Here? 206
References 207
Giant Mole-rats, Fukomys mechowii, 13 Years on the Stage 209
15.1 Introduction 209
15.2 Taxonomy, Nomenclature and Phylogeny 210
15.3 Morphology of the Giant Mole-rats 211
15.4 Distribution 213
15.5 Burrow Systems 214
15.6 Food 215
15.7 Colony Size and Structure 216
15.8 Sex Ratio 217
15.9 Surface Activity 218
15.10 Economic Importance 219
References 221
Biology of the Silvery Mole-rat ( Heliophobius argenteocinereus). Why Study a Neglected Subterranean Rodent Species? 224
16.1 Introduction 224
16.2 Taxonomy and Body Size 225
16.3 Population Density and Structure 227
16.4 Food and Habitat Preferences 228
16.5 Burrow Systems and Burrowing 229
16.6 Reproduction 229
16.7 Economic and Epidemiological Importance 233
16.8 Parasites and Sociality in African Mole-rats 233
16.9 Evolution of Sociality in the African Mole-rats 234
16.10 Further Perspectives 236
References 237
The Biology and Ecology of Plateau Zokors ( Eospalax fontanierii) 240
17.1 Introduction 240
17.2 Morphological Characteristics 241
17.3 Physiological Characteristics 241
17.4 Habitat Selection and Distribution 243
17.5 Burrow Systemand Environment 243
17.6 Foraging and Diet 244
17.7 Activity Rhythms 244
17.8 Reproduction 245
17.9 Dispersal 245
17.10 Territoriality and Home Range 246
17.11 Population Dynamics 246
17.12 Burrow Cohabitants 247
17.13 Plateau Zokors as Prey 247
17.14 Relationship of Plateau Zokors and Livestock 248
17.15 Conclusion 249
References 250
Senescence Patterns in African Mole-rats ( Bathyergidae, Rodentia) 253
18.1 Introduction 253
18.2 Longevity of Bathyergid Mole-rats Compared to Other Rodent Families 254
18.3 Intrafamilial Longevity Patterns 256
18.4 Intraspecific Aging Rates in Eusocial Bathyergids 259
18.5 “ Caste”-Specific Aging: Possible Explanations 260
18.6 Conclusions and Perspectives 263
References 264
Part IV Environmental and Economic Aspects 266
The Influence of Subterranean Rodents on the Environment 267
References 269
The Influence of Pocket Gophers on the Biotic and Abiotic Environment 271
20.1 Introduction 271
20.2 Burrowing Activity 271
20.3 Geometry of Disturbances 272
20.4 Activity Patterns 273
20.5 Diets 274
20.6 Impact on Plants 275
20.7 Complex Biotic Interactions 278
20.8 Soil Dynamics 279
20.9 Economic Impacts 281
20.10 Conclusion 282
References 283
Subterranean Rodents as Pests: The Case of the Pocket Gopher 287
21.1 Introduction 287
21.2 Pocket Gophers (Family Geomyidae) 288
21.3 Damage by Pocket Gophers 288
21.4 Pocket Gopher Damage Management 293
21.5 Conclusions and Future Needs 296
References 297
Influence of Plateau Zokors ( Eospalax fontanierii) on Alpine Meadows 300
22.1 Introduction 300
22.2 Effects on Soil and Nutrients 301
22.3 Effects on Vegetation and Diversity 302
22.4 Effects on Monocotyledons 302
22.5 Effects on Dicotyledons 304
22.6 Conclusion 305
References 306
Mountain Beaver: A Primitive Fossorial Rodent 308
23.1 Introduction 308
23.2 Distribution of the Aplodontidae Family 309
23.3 Mountain Beaver Ecology 309
23.4 Management and Economic Impacts 315
23.5 Conclusion and Future Research Needs 316
References 318
Part V Molecular Ecology and Evolution 321
Molecular Ecology and Evolution 322
References 325
The Multiple Meanings of Inbreeding: The Key to Understanding the Social and Genetic Structure of Subterranean Rodent Populations 327
25.1 Introduction 327
25.2 Determinants of Genetic Structure: Mutation, Selection, or Drift 327
25.3 The Influence of Social Structure on Genetic Structure and Genetic Structure on Social Structure 329
25.4 Genetic Structure and Social Structure in Naked Mole- rats: A Classic Example of the Importance of Understanding the Multiple Meanings of Inbreeding 329
25.5 Dispersal 332
25.6 Conclusions 333
References 333
Behavior, Demography, and Immunogenetic Variation: NewInsightsfromSubterranean Rodents 337
26.1 Introduction 337
26.2 Genetic Structure in Subterranean Rodents 338
26.3 MHC Variation in Subterranean Rodents 341
26.4 Overview and Future Directions 346
References 347
African Mole-rats (Bathyergidae): A Complex Radiation in Tropical Soils 352
27.1 Introduction 352
27.2 Intergeneric Relationships 353
27.3 Biogeography of the Bathyergidae 354
27.4 Overview of the Six Genera 357
27.5 Diversification in Social Mole-rats of the Genera Cryptomys Gray, 1864 and Fukomys ( Kock, Ingram, Frabotta, Honeycutt and Burda 2006) 358
27.6 Prospects (for Phylogenetic Studies and Beyond) 362
References 365
Mosaic Evolution of Subterranean Mammals: Tinkering, Regression, Progression, and Global Convergence 369
28.1 Overview 369
28.2 Visual Adaptations in Subterranean Mammals 371
28.3 Evolutionary Adaptive Regulation ofWide Genome Gene Expression 378
References 380
Subject Index 383