Gorilla Biology: A Multidisciplinary Perspective

Half-title......Page 3
Series-title......Page 5
Title......Page 7
Copyright......Page 8
Dedication......Page 9
Contents......Page 11
Contributors......Page 15
Acknowledgments......Page 21
Epigraph......Page 22
Introduction: Gorilla biology: Multiple perspectives on variation within a genus......Page 23
Part 1 Gorilla taxonomy and comparative morphology......Page 31
1 An introductory perspective: Gorillas – How important, how many, how long?......Page 33
References......Page 35
Prologue......Page 37
The gorilla becomes known to science......Page 38
Early studies on the gorilla’s anatomy......Page 39
Paul Matschie: Let a hundred species bloom......Page 40
Pygmy gorillas?......Page 43
Order out of chaos......Page 44
Recent understanding of the anatomy of the gorilla: Normal and pathological......Page 47
Epilogue......Page 48
References......Page 53
Introduction......Page 57
Materials and methods......Page 58
Analysis of raw measurements......Page 62
Analysis of size-adjusted measurements (shape)......Page 68
Discussion......Page 76
References......Page 81
Introduction......Page 84
Gorillas in paleoanthropological fossil species recognition studies......Page 85
Population thinking, intraspecific variation, and the hierarchy of morphological variation......Page 87
Materials and methods......Page 89
Sampling strategy......Page 91
Measurements......Page 94
Principal components analysis......Page 95
Overall species level variation......Page 98
Sexual dimorphism......Page 100
Subspecific level variation......Page 104
Demic level variation......Page 106
Locality level variation......Page 107
Sexual dimorphism......Page 108
Intraspecific variation within sexes......Page 111
Population thinking and species structure......Page 113
Implications for interpreting fossil variation......Page 115
Sampling strategy for constructing yardsticks......Page 116
Concluding remarks......Page 119
Acknowledgments......Page 120
References......Page 121
Introduction......Page 126
Morphology......Page 127
Molecular variation......Page 129
Ecology and social behavior......Page 130
Gorillas and subspecies......Page 131
Craniometrics......Page 132
Discrete traits......Page 133
F and morphological variation......Page 134
F estimation......Page 135
Population size, morphometric size adjustment, and heritability......Page 136
Discrete trait analyses......Page 137
F estimation......Page 138
Discrete trait analyses......Page 140
Degree of variation in Gorilla......Page 141
Comparisons to other species......Page 142
Concordance and variation......Page 144
Evolutionary history......Page 146
Conservation issues......Page 147
Acknowledgments......Page 148
References......Page 149
Introduction......Page 154
Cranial, dental, and mandibular variation......Page 155
Morphological correlates of folivory/herbivory......Page 159
Morphological predictions in gorilla subspecies......Page 161
Gorillas as a comparative model......Page 165
Samples......Page 166
Measurements......Page 167
Methodological approach......Page 168
Statistical approach......Page 169
Results......Page 172
Discussion......Page 183
Do gorilla subspecies differ in craniomandibular size?......Page 184
Ontogeny and allometry of jaw form in gorillas......Page 186
Adaptive differences in masticatory form......Page 189
Discrepancies between theoretical predictions and morphology......Page 191
Summary of morphological findings......Page 195
Evolutionary implications......Page 197
Gorilla taxonomy......Page 199
Conclusions......Page 201
References......Page 202
Introduction......Page 216
Subspecies of Gorilla......Page 217
Taxonomic issues......Page 218
Variation in positional and locomotor behavior in Gorilla......Page 219
Morphological variation in Gorilla......Page 220
Scapula......Page 222
Hands and feet......Page 223
Other postcranial comparisons......Page 226
Allometry and ontogeny......Page 227
Ontogenetic “criterion-of-subtraction”......Page 228
Shoulder......Page 230
Multivariate regression analyses......Page 232
Bivariate regression analyses......Page 235
Shoulder......Page 236
Elbow......Page 238
Wrist......Page 239
Summary of results......Page 241
Arboreality versus terrestriality: the relationship between form and function......Page 242
Evolution of knuckle-walking in the African apes......Page 244
Taxonomic status of Gorilla......Page 247
Conclusions......Page 249
References......Page 250
Part 2 Molecular genetics......Page 259
8 An introductory perspective: Gorilla systematics, taxonomy, and conservation in the era of genomics......Page 261
References......Page 266
Previous genetic results......Page 269
Goals of the study......Page 271
Loci examined......Page 272
Data analyses......Page 274
MtDNA......Page 275
Nuclear DNA......Page 278
Sequencing results......Page 280
Explaining the difference between Pan and Gorilla......Page 281
Implications for Gorilla taxonomy and biogeography......Page 282
Implications for other species......Page 283
Conclusions......Page 284
References......Page 285
Classification......Page 291
Origins of divergence......Page 293
Conservation genetics......Page 294
Noninvasive sampling strategies......Page 295
Feces......Page 296
Mitochondrial DNA......Page 297
Genetic studies of lowland gorillas throughout central Africa......Page 298
Mitochondrial DNA analysis......Page 300
Microsatellite DNA analysis......Page 303
Gorilla phylogeography......Page 307
Central African Republic......Page 308
Conservation implications......Page 309
References......Page 310
Part 3 Behavioral ecology......Page 315
11 An introductory perspective: Behavioral ecology of gorillas......Page 317
References......Page 322
Introduction......Page 324
The ecological model of primate female relationships......Page 325
Mountain gorilla females and the ecological model......Page 326
Male infiuence on female grouping......Page 327
Male influences on relationships between females......Page 329
Male–male relationships and male life histories......Page 330
An analysis of long-term consistency and change in male–female relationships: A case study......Page 331
Possible differences from mountain gorillas......Page 337
Other primates......Page 339
Group-living equids......Page 341
Summary and conclusions......Page 343
References......Page 344
Introduction......Page 350
Study site and methods......Page 352
Ecology of the Kahuzi and Itebero sites......Page 354
Ape habituation and density estimates......Page 356
Phenology of fruits and diet of gorillas......Page 357
Group size and fruit abundance......Page 359
Day range......Page 361
Intergroup relationships......Page 362
Relationships with sympatric chimpanzees......Page 363
Group size and frugivory in gorillas......Page 364
Within-group competition and foraging strategy of gorillas......Page 367
Sympatry with chimpanzees......Page 369
Conclusions......Page 371
References......Page 372
Introduction......Page 380
Highland versus lowland gorillas......Page 381
Predicting comparative behavioral ecology of lowland and mountain gorillas: The bonobo/chimpanzee analogy......Page 382
Study sites and subjects......Page 384
Data collection......Page 385
Vegetation diversity/density and diet......Page 387
Foraging effort......Page 388
Group cohesion......Page 391
The formation of temporary subgroups......Page 393
Results of within-population comparisons......Page 394
Discussion......Page 397
Bwindi gorillas......Page 399
Lowland/highland gorillas and the bonobo and chimpanzee analogy: Where do Bwindi gorillas fit?......Page 400
Acknowledgments......Page 401
References......Page 402
Introduction......Page 407
Field research at Bai Hokou, Central African Republic......Page 409
Captive research at the San Francisco Zoological Gardens......Page 410
Food availability and gorilla diet at Bai Hokou......Page 411
Nutritional analyses of foliage and fruits: Consequences of dietary flexibility......Page 413
Comparison of nutritional composition of gorilla diet across sites......Page 414
Captive research on food preferences and taste sensitivity......Page 417
Gorillas as seasonal frugivores......Page 418
Are gorillas vacuum cleaners of the forest floor?......Page 420
References......Page 421
Part 4 Gorilla conservation......Page 427
16 An introductory perspective: Gorilla conservation......Page 429
References......Page 434
The status of gorilla populations......Page 436
Habitat loss or modification......Page 440
Hunting or poaching......Page 441
Disease transmission......Page 443
War and political unrest......Page 445
Protected areas......Page 446
Working with logging companies......Page 448
Conclusions......Page 449
References......Page 450
Introduction......Page 454
Distribution......Page 455
Western gorillas (Gorilla gorilla)......Page 457
Local distribution......Page 462
Gorilla censusing......Page 463
Estimates based on transect nest counts......Page 470
Demography and censuses......Page 473
Gorilla taxonomy......Page 474
Genetics and alpha taxonomy......Page 475
Genetics and conservation......Page 476
Gorilla habitats......Page 477
Diet and behavior......Page 478
Habitat structure and food distribution......Page 479
Life forms coexisting with gorillas......Page 480
Conclusions......Page 482
References......Page 484
19 The Cross River gorilla: Natural history and status of a neglected and critically endangered subspecies......Page 494
Geographical range......Page 495
Taxonomy and cranial morphology......Page 496
Genetics......Page 498
Ecology......Page 500
Grouping patterns......Page 507
Present distribution......Page 508
Numbers......Page 509
Threats and trends......Page 511
Conservation efforts and options......Page 512
References......Page 515
Afterword......Page 520
Index......Page 523