FIRST ECOLOGY JOIN US ON THE INTERNET VIA WWW, GOPHER, FTP OR EMAIL: WWW: http://www.thomson.com GOPHER: gopher.thomson.com A service 01 ICDP" FTP: ftp.thomson.com EMAIL: [email protected] FIRST ECOLOGY Alan Beeby and Anne-Maria Brennan School of Applied Science University of the South Bank London, UK Springer-Science+Business Media, B.Y. First edition 1997 © 1997 Alan Beeby and Anne-Maria Brennan Originally published by Chapman and Hall in 1977. Typeset in 10/11 pt Times by Saxon Graphics Ltd, Derby ISBN 978-0-412-63060-6 ISBN 978-1-4899-3262-4 (eBook) DOI 10.1007/978-1-4899-3262-4 Apart from any fair dealing for the purposes of research or private study, or criticism or review, as pem1itted under the UK Copyright Designs and Patents Aet, 1988, this publieation may not be reprodueed, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the ease of reprographie reproduetion only in aeeordanee with the terms of the lieenees issued by the Copyright Lieensing Agency in the UK, or in aecordanee with the terms of licences issued by the appropriate Reproduetion Rights Organization outside the UK. Enquiries coneerning reproduetion outside the terms stated here should be sent to the publishers at the London address printed on this page. The publisher makes no representation, express or implied, with regard to the aeeuraey of the information contained in this book and eannot aeeept any legal responsibility or liability for any errors or omissions that may be made. A eatalogue reeord for this book is available from the British Library It is true: Man is the microcosm: I am my world. Ludwig Wittgenstein Contents Guest contributors xi First words xiii Acknow ledgements xv Prologue Michael C. Newman 1 1 Origins 9 1.1 Origins of humanity 9 1.2 Evolution by natural selection 13 1.2.1 The blooms and the bees 18 1.3 Sources of variation 19 1.4 Rates of evolution 22 1.5 The origins of life 23 1.6 Origins of the major groups 25 Summary 26 Further reading 28 Exercises 28 2 Species 31 2.1 What's in a name 32 2.2 The species 35 2.2.1 The biological species 37 2.2.2 Defining species by their chemistry 38 2.3 Variation within a population 42 2.4 Ecologieal niehe 42 2.4.1 Niche and competition 44 2.5 Speciation 47 2.5.1 Allopatric speciation 47 2.5.2 Reproductive barriers 48 2.5.3 Sympatric speciation 49 2.5.4 Man-made species 53 Summary 55 Further reading 55 Exercises 56 3 Popnlations 59 3.1 Modelling 60 3.2 Simple models of population growth 60 3.2.1 Populations with overlapping generations 62 3.2.2 Factors affecting the rate of population growth 63 3.2.3 Populations in limited environments 63 3.2.4 What determines the carrying capacity? 65 3.3 Harvesting a population 65 viii CONTENTS 3.3.1 Fishery models 65 3.4 Growth rates, age and recruitment 67 3.5 Life his tory strategies 69 3.5.1 The spectrum from r-selected to K-selected strategies 71 3.6 Survival and extinction 71 3.6.1 Persistence time and extinction 72 3.6.2 Fragmentation, extinction and colonization 72 3.6.3 The elephant and the rhinoceros 74 Summary 78 Further reading 79 Exercises 79 4 Interactions 81 4.1 Acquiring resources 82 4.2 Cooperation 82 4.2.1 Cooperating with different species 86 4.3 Competition 88 4.3.1 Intraspecific competition 90 4.3.2 Interspecific competition 90 4.3.3 Competitive types 91 4.4 Consumerism 93 4.4.1 Herbivory 93 4.4.2 Predation 95 4.4.3 In self-defence 99 4.4.4 Parasites and pathogens 100 4.5 Controlling pests 105 Summary 108 Further reading 109 Exercises 110 5 Systems 113 5.1 Ecological energetics 113 5.2 The producers 114 5.3 Links in the chain 123 5.3.1 The reducers 126 5.3.2 Chain length 126 5.4 The web 128 5.4.1 Are communities real? 131 5.5 Working the system 132 5.5.1 Why grow animals? 136 5.5.2 Getting the grazing right 138 5.5.3 Added energy 139 Summary 142 Further reading 143 Exercises 144 6 Balances 147 6.1 Nutrients as limiting factors 148 6.2 The nutrient cycles of life 148 6.2.1 The principal nutrients 150 CONTENTS ix 6.3 Eutrophication - too much of a good thing 159 6.3.1 Restoring eutrophie waters 161 6.3.2 Eutrophication in terrestrial ecosystems 162 6.4 Oil pollution 163 6.5 Restoration - the 'acid test of ecology' 164 6.5.1 The three Rs of restoration 164 6.5.2 The time factor 166 6.5.3 Restoration methods 167 6.5.4 The limits of restoration 170 Summary 170 Further reading 171 Exercises 171 7 Communities 175 7.1 Mediterranean communities 176 7.1.1 The role of fire 178 7.1.2 Animal communities 181 7.1.3 Similarities 182 7.1.4 Integration 185 7.2 What are communities? 186 7.2.1 Change in communities 187 7.2.2 Assembling communities 187 7.2.3 Disturbance and succession 189 7.3 Succession and conservation 193 Summary 195 Further reading 199 Exercises 200 8 Scales 203 8.1 Landscape ecology 203 8.1.1 Hierarchy theory 206 8.2 The biogeography of Earth 208 8.2.1 Tropical biomes 211 8.2.2 Temperate biomes 214 8.2.3 Boreal biomes 216 8.3 Climate change 218 8.3.1 Atmospheric composition and mean temperature 218 8.3.2 Anthropogenic sources of atmospheric carbon 219 8.3.3 Predicting climate change 220 8.3.4 Ecological changes likely with atmospheric warming 225 8.3.5 Changes in primary productivity 226 8.3.6 Changes in decomposition 227 8.3.7 Stabilizing the atmosphere: ecological methods 227 Summary 228 Further reading 229 Exercises 230 9 Checks 233 9.1 Ecological stability 233 9.2 Stability and diversity 237 x CONTENTS 9.3 The big questions: latitudinal gradients in diversity 240 9.4 Extinctions 245 9.5 The scale of human disturbance 248 9.6 Last, ecology 256 Summary 256 Further reading 257 Exercises 257 Appendix A: Glossary 261 Appendix B: Answers to exercises 267 Bibliography 275 Index 287