Preface 1
Contents 1
Chapter 1 Introduction 2
1.1 What is ecology? 2
1.2 The nature of ecology 3
1.3 The study of ecology 3
Chapter 2 The individual 5
2.1 Why look at individuals in ecology? 5
2.2 Autotrophs and heterotrophs 5
2.2.1 Terms associated with heterotrophic nutrition 5
2.2.2 Ingestion by heterotrophs 6
2.3 Metabolic rate 7
2.4.1 Size 9
2.4.2 Life style 9
2.5 Size determines more than metabolic rate 10
2.6.1 Assimilation efficiency 11
2.6 2 Production and respiration 11
2.6 Energy budgets 11
2.6.3 Allocation to reproduction 12
2.6.4 Drawing up a complete energy budget 12
2.7 Distinguishing between growth and reproduction 13
Chapter 3 Autecology 16
3.1 The meaning of autecology 16
3.2 The autecology of bracken 16
3.2.1 The importance of bracken 16
3.2.2 The life form of bracken 17
3.2 3 Anti-predator mechanisms 18
2.4 Factors affecting metabolic rate 19
3.3 The autecology of the European starling 19
3.3.1 Appearance and distribution 19
3.3.2 Feeding habits 20
3.3.3 Roosting behaviour of starlings 21
3.3.4 Reproduction 22
3.3.5 Starlings and humans 22
Chapter 4 Population dynamics 23
4.1 Populations and population change 23
4.2 Dispersal of organisms 24
4.3 Dormancy 24
4.4 The study of populations 25
4.4.1 The basic equation 25
4.4.2 Age structure in populations 25
4.5.1 Life tables 29
4.5 Presentation of demographic data 29
4.4.5 Long-term population studies 29
4.4.3 The fate of a cohort 29
4.4.4 Age at death 29
4.5.2 Population pyramids 30
4.5.3 Survivorship curves 30
4.6 Evolutionary strategies 32
4.6.1 Strategies as shown by survivorship curves 32
4.6.2 r-and K-strategies 32
4.7 Modular organisms 34
5.1 Population growth 37
5.1.1 Population growth without regulation-exponential growth 37
Chapter 5 Population regulation 37
5.1.2 Simple population regulation-the logistic growth curve 38
5.2 Factors which regulate population size 39
5.2.1 Types of regulation 39
5.2.2 Space 41
5.2.3 Food and water 42
5.2.4 Territories 43
5.2.5 Herbivores and predators 44
5.2.6 Weather and climate 45
5.2.7 Parasites and diseases 45
5.2.8 Natural disasters 46
5.2.9 Self-regulation and stress 47
5.3 Patterns in population dynamics 48
Chapter 6 Ecological genetics 51
6.1 The importance of genetics to ecology 51
6.1.1 The source of variation 51
6.1.2 Genetic and environmental variation 51
6.1.3 The role of variation in natural selection 51
6.2 Reproductive systems 52
6.2.1 Formation of genetic variation 52
6.2.3 Facultative cross-fertilisation 53
6.2.4 Self-fertilisation 53
6.2.2 Obligate cross-fertilisation 53
6.2 5 Seed apomixis 54
6.2.6 Vegetative reproduction 55
6.3 Genetic consequences of different reproductive systems 55
6.3.1 The source of inherited chromosomes 55
6.3.2 The consequences of outcrossing 55
6.3.3 The consequences of self-fertilisation 56
6.3.4 The consequences of asexual reproduction 57
6.4 Patterns of genetic variation 58
6.4.1 External influences on genetic variation 58
6.4.2 Founder effects and bottlenecks 58
6.4.4 Ecotypes and ecoclines 59
6.4.3 Isolation of populations 59
6.5 Genetic variation within an organism 63
Chapter 7 Behavioural ecology 64
7.1 What is behavioural ecology? 64
7.2 Optimisation theory 64
7.3 Optimal foraging 64
7.3.1 Optimal foraging in crows 64
7.3.2 Foraging in African elephants 65
7.3.3 Optimal foraging in plants 66
7.4 Growth versus reproduction 68
7.5 Reproducing only once versus reproducing several times 68
7.6.2 Which sex looks after the offspring? 69
7.6 Parental care 69
7.6.1 Offspring size 69
7.7 Breeding systems in plants 70
7.8 Alternative strategies 71
7.9 Games theory 72
7.10 Constraints on adaptation 74
7.10.1 Time lags 75
7.10.2 Historical constraints 75
7.10.3 Lack of genetic variation 76
8.2.1 Less risk of predation 77
8.2 The advantages of group living 77
8.1 Living in groups 77
Chapter 8 Sociobiology 77
8.2.2 More chance of obtaining food 78
8.2.3 Other advantages of group living 78
8.3 Disadvantages of group living 79
8.4 Optimal group size 80
8.5 Evolution of helping behaviour 80
8.5.1 Kin selection 80
8.5.2 Reciprocal altruism 81
8.6.1 Termites 83
8.6 The unit of selection and social behaviour 83
8.5.3 Group selection 83
8.6.2 Army ants 84
8.6.3 Lions 86
8.6.4 Naked mole rats 88
8.7 Human sociobiology 89
8.7.1 Parental investment in the iater mediaeval Portuguese nobility 90
8.7.2 Helping behaviour in humans 91
Chapter 9 The environment 92
9.1 What is the environment? 92
9.2.2 Geology and soil 93
9.2.1 The composition ofthe physical environment 93
9.2 The physical environment 93
9.2.3 Topography 96
9.2.4 Latitudinal light and temperature variation 97
9.2.5 Climate and weather 97
9.2.6 Catastrophes 101
9.3 The biotic environment 101
9.3.1 Types of interaction 101
9.3.2 Intraspecific relationships(within species) 101
9.3.3 Interspecific relationships(between species) 102
9.4.2 Pathogens and climate 103
9.4.1 The complexity of the environment 103
9.4 Biotic and abiotic interactions 103
9.4.3 Abiotic effects on competition 104
Chapter 10 Habitats and niches 106
10.1 Habitats 106
10.2 Niches 106
10.2.1 Determining niches 106
10.2.2 Each species has its own unique niche 108
10.3 Gause's competitive exclusion principle 110
10.4 Species coexistence 112
1O.4.1 Size ratios in closely related species 112
10.5 Fundamental and realised niches 113
10.4.2 Niche overlap and species coexistence 113
10.6 Resource partitioning 114
10.7 Character displacement 116
10.8 Interspecific competition in natural communities 116
10.9 Do plants need niches? 118
10.10 Community structure of fish on coral reefs 119
Chapter 11 Trophic levels 120
11.1 Why study trophiclevels? 120
11.2 Autotrophs 120
11.2.1 Photoautotrophs 120
11.2.2 Chemoautotrophs 121
11.3 Decomposers 122
11.3.1 Decomposition on the forest floor 123
11.3.2 Decomposition of dead plant matter 124
11.4 Herbivores and carnivores 125
11.5 Omnivores 126
11.6 Food chains 126
11.7 Food webs 128
11.8 Pyramids of numbers 129
11.9 Pyramids of biomass 130
12.2 Primary production in terrestrial communities 132
12.1 Energy and disorder 132
Chapter 12 Energy transfer 132
12.3 Primary production in aquatic communities 136
12.4 The capture of light by plants 136
12.5 Efficiencies in ecology 137
12.6 Energy flow in natural communities 137
12.6.1 Odum's (1957)study at Silver Springs Florida 138
12.6.2 Teal's(1962)study at a salt marsh in Georgia 138
12.6.3 Varley's (1970)study ofWytham Wood,Oxford 140
12.7 The efficiency of energy transfer in ecosystems 142
12.8 Pyramids of energy 144
13.1 The pattern of nutrient transfer and its connection with pollution 147
Chapter 13 Nutrient cycling and pollution 147
13.2 The carbon cycle 148
13.3 The greenhouse effect 149
13.4 The nitrogen cycle 152
13.5 The phosphorus cycle 155
13.6 Interactions between the nutrient cycles 155
13.7 The importance of nutrient availability 156
13.7.1 The response of organisms to nutrient availability 156
13.7.2 China clay waste tips 157
13.8.1 Different forms of pollution 158
13.8 Pollution 158
13.7.3 Nutrient cycling in tropical forests 158
13.8.2 Eutrophication 159
13.8.3 Heavy metal toxicity 160
13.8.4 Alkaline wastes 161
13.8.5 Acid rain 161
13.8.6 Pesticides 163
13.8.7 CFCs and the ozone layer 165
13.8.8 Radioactivity 166
14.1.2 Recognition of communities 168
14.2.1 The investigation of communities 168
14.2 The structure of communities 168
14.1.1 Definitions 168
14.1 The community concept 168
Chapter 14 Communities 168
14.2.2 Oak woodland communities 169
14.2.3 Marine rock pools 172
14.2.4 Mammalian gut communities 174
14.3 Global distribution of terrestrial communities 178
14.4 Patterns of diversity 181
14.4.1 Global diversity 181
14.4.2 Species richness in-a community 181
14.4.3 Stability-diversity relationships 183
14.4.4 The global cline 184
Chapter 15 Ecosystems 187
15.1 The first use of ecosystem 187
15.2 Soils 187
15.2.1 The structure of soils 187
15.2.2 The great soil groups 190
15.2.3 The effect of vegetation on soil-two case studies 194
15.3 Wetland and aquatic ecosystems 196
15.3.1 Water-the important factor 196
15.3.3 Marine wetland ecosystems 197
15.3.2 Types of wetlands 197
15.3.4 Floodland ecosystems 198
15.3.5 Swamp and marsh ecosystems 199
15.3.6 Bog ecosystems 200
15.3.7 Aquatic ecosystems 201
15.4 Inter-relationships of ecosystems 204
Chapter 16 Succession 206
16.1 Vegetation changes 206
16.2 The causes of change 207
16.3 Examples of primary seres 208
16.3.1 Xeroseres 208
16.3.2 Hydroseres 210
16.4.1 Variation in seres 211
16.4 Patterns of succession 211
16.4.2 The end of the succession 212
16.4.3 Diverted seres 213
16.5 Human influence on succession 215
Chapter 17 Biomes 217
17.1 How many biomes are there? 217
17.2 The world's terrestrial biomes 217
17.2.1 Tropical rainforest 217
17.2.5 Thornwood 219
17.2.6 Temperate rainforest 219
17.2.3 Tropical seasonal forest 219
17.2.4 Tropical broad-leaved woodland 219
17.2.2 Elfinwood 219
17.2.7 Temperate deciduous forest 220
17.2.8 Temperate evergreen forest 220
17.2.9 Temperate woodland 221
17.2.10 Temperate shrubland 221
17.2.11 Boreal forest 221
17.2.12 Savannah 222
17.2.13 Temperate grassland 223
17.2.16 Tundra 224
17.2.15 Alpine grassland 224
17.2.14 Alpine shrubland 224
17.2.17 Warm semi-desert scrub 225
17.2.18 Cool semi-desert 225
17.2.19 Arctic-alpine semi-desert 225
17.2.20 Desert 225
17.3.2 Tropical freshwater swamp forest 227
17.3.4 Lakes and ponds 227
17.3.3 Temperate freshwater swamp forest 227
17.3.1 Cool temperate bog 227
17.3 Wetland and freshwater biomes 227
17.2.21 Arctic-alpine desert 227
17.3.5 Streams and rivers 228
17.4 Coastal and marine biomes 228
17.4.1 Marine rocky shore 228
174.2 Marine sandy beach 229
17.4.3 Marine mud fiat 230
17.4.4 Temperate salt marsh 230
17.4.5 Mangrove swamp 230
17.4.6 Coral reef 230
17.4.7 Marine surface pelagic 231
17.4.9 Continental shelf benthos 232
17.4.8 Marine deep pelagic 232
17.4.10 Deep ocean benthos 233
Chapter 18 Biogeography 235
18.1 Species distribution-where and why? 235
18.2 The historic effects of plate tectonics 236
18.2.1 Past continental movements 236
18.2.2 Present patterns of biogeography 239
18.3 Island biogeography 241
18.3.1 The fascination of islands 241
18.3.2 Colonisation of isolated islands 241
18.3.3 The equilibrium theory 244
18 3.4 Evolution on islands 245
18.3.5 Mountain islands 249
Chapter 19 Co-evolution 252
19.1 The different grades of co-evolution 252
19.2 Pairwise co-evolution 253
19.2.1 Generai aspects of one-on-one relationships 253
19.2.2 The ant-acacia example 255
19.3 Diffuse co-evolution 256
19.3.1 Co-evolution between groups of species 256
19.3.2 The mammalian predator-prey example 257
19.4.1 Angiosperm-pollinator relationships 258
19.4 Insect pollination 258
19.3.3 The Red Queen hypothesis 258
19.4.2 The early evolution of insect pollination 261
19.4.3 Orchids and Hymenoptera 262
19.5 Introduced species 263
Chapter 20 Conservation principles 268
20.1 Biology is not enough 268
20.2 The need for conservation 268
20.2.1 The pressure on wildlife 268
20.3 The philosophical basis for conservation 269
20.3.1 Ethical arguments 269
20.2.2 Maintaining biodiversity 269
20.3.2 Anthropocentric arguments 272
20.3.3 The role of ecology 272
20.4 Conservation of species 273
20.4.1 Why do species become extinct? 273
20.4.2 Genetic diversity in rare species 275
20.4.3 Captive breeding programmes 277
20.4.4 Re-introductions 277
20.5 Conservation of ecosystems 279
20.5.1 The importance of habitat conservation 279
20.5.2 Design of nature reserves 280
20.5.3 Maintenance of conservation areas 281
20.6 Conservation of the biosphere 283
Chapter 21 Conservation in practice 284
21.1 The realities of attempting conservation 284
21.2 Conservation of species 284
21.2.1 The golden lion tamarin-a successfulre-introduction 284
21.2.2 The African elephant-protective legislation 285
21.2.3 The tiger-teetering on the edge of extinction 286
21.2.4 Northern spotted owl-habitat destruction 287
21.2.5 Spreading avens-habitat management 288
21.2.6 Partula snails-captive breeding 289
21.3.1 Dif.ferent models of conservation 290
21.3 Conservation of ecosystems 290
21.3.2 UK legislation 291
21.3.3 Tropical rainforest 292
21.3.4 Wetlands 293
21.4 Conservation of the biosphere 296
21.4.1 The greenhouse effect 296
21.4.2 Conserving the seas 298
21.5 What can individuals do? 300
Glossary 303
Bibliography 311
Index 327