Island Biogeography Ecology, Evolution, and Conservation

by Whittaker, Robert J.; Fernández-Palacios, José María

• ISBN13: 9780198566120
• ISBN10: 0198566123
• Edition: 2nd
• Format: Paperback
• Copyright: 2007-02-08
• Publisher: Oxford University Press

Summary

Island biogeography is the study of the distribution and dynamics of species in island environments. Due to their isolation from more widespread continental species, islands are ideal places for unique species to evolve, but they are also places of concentrated extinction. Not surprisingly, they are widely studied by ecologists, conservationists and evolutionary biologists alike. There is no other recent textbook devoted solely to island biogeography, and a synthesis of the many recent advances is now overdue. This second edition builds on the success and reputation of the first, documenting the recent advances in this exciting field and explaining how islands have been used as natural laboratories in developing and testing ecological and evolutionary theories. In addition, the book describes the main processes of island formation, development and eventual demise, and explains the relevance of island environmental history to island biogeography. The authors demonstrate the huge significance of islands as hotspots of biodiversity, and as places from which disproportionate numbers of species have been extinguished by human action in historical time. Many island species are today threatened with extinction, and this work examines both the chief threats to their persistence and some of the mitigation measures that can be put in play with conservation strategies tailored to islands.

Author Biography

Robert J. Whittaker is Professor of Biogeography at the Oxford University Centre for the Environment
Jose Maria Fernandez-Palacios is Professor of Ecology at the La Laguna University, Tenerife

Table of Contents

Preface and acknowledgements	p. v
Islands as Natural Laboratories	p. 1
The natural laboratory paradigm	p. 3
Island environments	p. 10
Types of islands	p. 10
Modes of origin	p. 12
Plate boundary islands	p. 16
Islands in intraplate locations	p. 20
Environmental changes over long timescales	p. 22
Changes in relative sea level-reefs, atolls, and guyots	p. 22
Eustatic changes in sea level	p. 24
Climate change on islands	p. 26
The developmental history of the Canaries, Hawaii, and Jamaica	p. 27
The physical environment of islands	p. 32
Topographic characteristics	p. 32
Climatic characteristics	p. 34
Water resources	p. 36
Tracks in the ocean	p. 37
Natural disturbance on islands	p. 38
Magnitude and frequency	p. 40
Disturbance from volcanism and mega-landslides	p. 41
Summary	p. 45
The biogeography of island life: biodiversity hotspots in context	p. 46
Introduction: the global significance of island biodiversity	p. 46
Species poverty	p. 49
Disharmony, filters, and regional biogeography	p. 50
Filtering effects, dispersal limits, and disharmony	p. 50
Biogeographical regionalism and the vicariance/dispersalism debate	p. 52
Macaronesia-the biogeographical affinities of the Happy Islands	p. 60
Endemism	p. 63
Neo- and palaeoendemism	p. 63
Endemic plants	p. 65
Endemic animals	p. 67
Cryptic and extinct island endemics: a cautionary note	p. 71
Summary	p. 73
Island Ecology	p. 75
Species numbers games: the macroecology of island biotas	p. 77
The development of the equilibrium theory of island biogeography	p. 79
Island species-area relationships (ISARs)	p. 81
Species abundance distributions	p. 82
The distance effect	p. 83
Turnover, the core model (EMIB), and its immediate derivatives	p. 84
Competing explanations for systematic variation in island species-area relationships	p. 87
Island species numbers and ISARs: what have we learnt?	p. 89
Area and habitat diversity	p. 89
Area is not always the first variable in the model	p. 90
Distance and species numbers	p. 91
Species-area relationships in remote archipelagos	p. 92
Scale effects and the shape of species-area relationships	p. 93
Species-energy theory-a step towards a more complete island species richness model?	p. 97
Turnover	p. 99
Pseudoturnover and cryptoturnover	p. 100
When is an island in equilibrium?	p. 101
The rescue effect and the effect of island area on immigration rate	p. 102
The path to equilibrium	p. 103
What causes extinctions?	p. 104
Summary	p. 106
Community assembly and dynamics	p. 107
Island assembly theory	p. 107
Assembly rules	p. 108
Incidence functions and tramps	p. 108
The dynamics of island assembly	p. 110
Chequerboard distributions	p. 111
Combination and compatibility-assembly rules for cuckoo-doves	p. 111
Criticisms, 'null' models, and responses	p. 113
Exploring incidence functions	p. 118
Linking island assembly patterns to habitat factors	p. 122
Anthropogenic experiments in island assembly: evidence of competitive effects?	p. 125
Nestedness	p. 126
Successional island ecology: first elements	p. 129
Krakatau-succession, dispersal structure, and hierarchies	p. 131
Background	p. 131
Community succession	p. 131
A dispersal-structured model of island recolonization	p. 134
Colonization and turnover-the dynamics of species lists	p. 136
The degree of organization in the Krakatau assembly process	p. 141
Concluding observations	p. 143
Summary	p. 143
Scale and island ecological theory: towards a new synthesis	p. 145
Limitations of the dynamic equilibrium model of island biogeography: a reappraisal	p. 145
Scale and the dynamics of island biotas	p. 147
Residency and hierarchical interdependency: further illustrations from Krakatau	p. 148
Forms of equilibria and non-equilibria	p. 150
Temporal variation in island carrying capacities	p. 156
The prevalence and implications of intense disturbance events	p. 156
Variation in species number in the short and medium term	p. 157
Long term non-equilibrium systems	p. 158
Implications for endemics?	p. 159
Future directions	p. 161
Summary	p. 164
Island Evolution	p. 165
Arrival and change	p. 167
Founder effects, genetic drift, and bottlenecks	p. 167
Implications of repeated founding events	p. 170
After the founding event: ecological responses to empty niche space	p. 172
Ecological release	p. 173
Density compensation	p. 174
Character displacement	p. 176
Sex on islands	p. 177
Dioecy and outcrossing	p. 177
Loss of flower attractiveness	p. 178
Anemophily	p. 178
Parthenogenesis	p. 178
Hybridization	p. 179
Peculiarities of pollination and dispersal networks on islands	p. 179
The emergence of endemic super-generalists	p. 180
Unusual pollinators	p. 181
Unusual dispersal agents	p. 181
Niche shifts and syndromes	p. 181
The loss of dispersal powers	p. 182
The development of woodiness in herbaceous plant lineages	p. 184
Size shifts in island species and the island rule	p. 186
Changes in fecundity and behaviour	p. 190
The island syndrome in rodents	p. 192
Summary	p. 194
Speciation and the island condition	p. 195
The species concept and its place in phylogeny	p. 195
The geographical context of speciation events	p. 199
Distributional context	p. 199
Locational and historical context-island or mainland change?	p. 201
Mechanisms of speciation	p. 202
Allopatric or geographical speciation	p. 202
Competitive speciation	p. 204
Polyploidy	p. 205
Lineage structure	p. 206
Summary	p. 207
Emergent models of island evolution	p. 208
Anagenesis: speciation with little or no radiation	p. 208
The taxon cycle	p. 209
Melanesian ants	p. 209
Caribbean birds	p. 211
Caribbean anolcs	p. 215
Evaluation	p. 217
Adaptive radiation	p. 217
Darwin's finches and the Hawaiian honeycreeper-finches	p. 219
Hawaiian crickets and drosophilids	p. 225
Adaptive radiation in plants	p. 228
From valley isolates to island-hopping radiations 230 Non-adaptive radiation	p. 230
Speciation within an archipelago	p. 230
Island-hopping allopatric radiations: do clades respond to islands or to habitats?	p. 233
Island-hopping on the grand scale	p. 237
Observations on the forcing factors of island evolution	p. 238
Variation in insidar endemism between taxa	p. 240
Biogeographical hierarchies and island evolutionary models	p. 245
Summary	p. 247
Islands and Conservation	p. 249
Island theory and conservation	p. 251
Islands and conservation	p. 251
Habitats as islands	p. 252
Minimum viable popidations and minimum viable areas	p. 253
How many individuals are needed?	p. 253
How big an area?	p. 257
Applications of incidence functions	p. 257
Metapopulation dynamics	p. 259
The core-sink model variant	p. 261
Deterministic extinction and colonization within metapopulations	p. 262
Value of the metapopulation concept	p. 263
Reserve configuration-the 'Single Large or Several Small' (SLOSS) debate	p. 263
Dealing with the leftovers	p. 266
Trophic level, scale, and system extent	p. 266
Physical changes and the hyperdynamism of fragment systems	p. 268
Relaxation and turnover-the evidence	p. 269
Succession in fragmented landscapes	p. 274
The implications of nestedness	p. 275
Edge effects	p. 276
Landscape effects, isolation, and corridors	p. 278
The benefits of wildlife corridors	p. 278
The benefits of isolation	p. 279
Corridors or isolation?	p. 281
Reserve systems in the landscape	p. 281
Species that don't stay put	p. 282
Does conservation biology need island theory?	p. 283
A non-equilibrium world?	p. 283
Ecological hierarchies and fragmented landscapes	p. 285
Climate change and reserve systems	p. 286
Concluding remarks: from island biogeography to countryside biogeography?	p. 287
Summary	p. 288
Anthropogenic losses and threats to island ecosystems	p. 290
Current extinctions in context	p. 290
Stochastic versus deterministic extinctions	p. 291
The scale of island losses globally	p. 292
The agencies of destruction	p. 295
Predation by humans	p. 295
Introduced species	p. 295
Disease	p. 300
Habitat degradation and loss	p. 302
Trends in the causes of decline	p. 302
A record of passage-patterns of loss across island taxa	p. 305
Pacific Ocean birds and the Easter Island enigma	p. 307
Indian Ocean birds	p. 312
Reptiles	p. 313
Caribbean land mammals	p. 314
Island snails	p. 315
Plants in peril	p. 316
How fragile and invasible are island ecosystems?	p. 320
Summary	p. 322
Island remedies: the conservation of island ecosystems	p. 323
Contemporary problems on islands	p. 323
Maldives: in peril because of climatic change	p. 323
Okino-Tori-Shima: the strategic economic importance of a rocky outcrop	p. 324
Nauru: the destruction of an island	p. 324
The Canaries: unsustainable development in a natural paradise	p. 325
Contemporary problems in the Galapagos: a threatened evolutionary showcase	p. 328
Some conservation responses	p. 329
Biological control-a dangerous weapon?	p. 331
Translocation and release programmes	p. 331
Protected area and species protection systems: the Canarian example	p. 333
Sustainable development on islands: constraints and remedies	p. 336
Summary	p. 340
Glossary	p. 342
References	p. 351
Index	p. 383
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