Title Page	3
	Copyright Page	4
	Table of Contents	5
	Dedication	12
	Preface	13
	List of figures	14
	List of tables	17
	List of abbreviations and acronyms	18
	1 Local-scale patterns in species richness	19
	1.1 Local-scale trends in species richness	19
	1.2 What is species richness?	19
	1.3 What is meant by "local" variations in species richness?	21
	1.4 Local-scale patterns are most noticeable in organisms that don't move around much	22
	1.5 A related and important question: How do species coexist anywhere?	22
	1.6 Different scales of species richness, from local to geographical	32
	1.7 A varied environment tends to allow more species in	34
	1.8 Using models to validate the logic of the role of disturbance in allowing coexistence	39
	1.9 Do humpback curves really occur along disturbance gradients?	41
	1.10 Grime and Tilman: disturbance creates other sorts of opportunities for coexistence, and variation in levels of disturbance affects these opportunities	43
	1.11 When strategies mix-the humpback curve with succession, after a disturbance	44
	1.12 The "other" humpback curve: along gradients in nutrient levels	45
	1.13 Species richness is a balancing act between the effects of disturbance and nutrients	51
	1.14 Why hasn't a humpbacked diversity curve been found for animals?	53
	1.15 A quite different explanation for humpbacked diversity curves in plants, in relation to soil fertility	55
	1.16 "Poisoned" and "extreme" environments are usually poor in species	58
	1.17 Mountain-scale patterns in species richness	59
	1.18 Patterns of species richness with depth in the oceans	62
	1.19 Some conclusions about local-scale patterns in species richness	63
	2 The Holy Grail of ecology: Latitudinal gradients	65
	2.1 Latitudinal trends	65
	2.2 The discovery of latitudinal trends	66
	2.3 Explaining latitudinal gradients	73
	2.4 Non-equilibrium theories: species richness can just keep on rising	78
	2.4.1 The effects of ice ages	78
	2.4.2 "The tropics are more benign"	82
	2.4.2.1 Are the tropics only more "benign" because most groups evolved in a past warmer world?	84
	2.4.2.2 Do species "fall into" the tropics?	86
	2.4.2.3 The mid-domain effect: Is the latitudinal gradient just the sum of chance overlap of ranges?	93
	2.4.2.4 Are species originating more easily and more often at lower latitudes?	95
	2.4.3 A general test of the disequilibrium theories: Has the build-up of species richness continued over time?	97
	2.5 Equilibrium theories: there is a lid on species richness that is higher in the low latitudes	99
	2.5.1 The tropics are just bigger	99
	2.5.2 More energy, more food in warmer climates: the "speciesenergy hypothesis"	99
	2.5.3 More strongly seasonal environments mean less chance of occupying a narrow, specialized niche	103
	2.5.4 More specialized enemies of plants mean more species can exist side by side at lower latitudes (the Janzen-Connell hypothesis)	105
	2.5.5 The latitudinal gradient is produced by a balance between growth and disturbance	110
	2.6 The pros and cons of the various theories for latitudinal gradients	112
	3 Deep time and mass extinctions	114
	3.1 The depth of time	114
	3.2 Species richness can change on a range of time scales	115
	3.3 Sampling the past: the fossil record and species richness	115
	3.4 The broadest scale picture of biological richness, since the beginning of life on Earth	117
	3.5 What caused the sudden initial increase in diversity 540 Myr ago?	122
	3.5.1 What could have caused the explosion of animal life after 600 Myr ago?	123
	3.5.2 Is the Cambrian Explosion just an effect of better preservation?	124
	3.6 How many species have ever existed?	125
	3.7 Background extinction	127
	3.7.1 The causes of background extinction	127
	3.8 Mass extinctions	130
	3.9 The main mass extinctions	130
	3.10 The end-Permian mass extinction	131
	3.11 The end-Cretaceous mass extinction	133
	3.12 The end-Ordovician mass extinction	134
	3.13 Other mass extinctions	135
	3.14 Mass extinctions affected species inhabiting many different environments	135
	3.15 The causes of mass extinctions	136
	3.16 Were mass extinctions sudden, or gradual?	136
	3.17 The paradigm shift towards acceptance of sudden mass extinctions	138
	3.18 There is evidence for dramatic environmental upheaval during mass extinctions	139
	3.19 Global collapse of ecosystems is associated with the "Biggest Two" mass extinctions	139
	3.20 Death of vegetation	141
	3.21 Empty seas	143
	3.22 Carbon-12 shifts in the oceans and what they might mean	143
	3.23 The Strangelove Ocean	144
	3.24 Sudden temperature swings	145
	3.25 The aftermath of mass extinctions: disaster taxa	147
	3.26 Causes of mass extinctions	148
	3.27 Did meteorite impacts bring about mass extinctions? The end-Cretaceous impact	149
	3.28 Did a meteorite cause the end-Permian extinction?	153
	3.29 Other possible impact events at times of mass extinction	154
	3.30 Volcanic eruptions as a cause of mass extinctions	154
	3.31 Stagnant, burping oceans as a cause of mass extinctions	156
	3.32 The end-Paleocene extinction in the deep sea	159
	3.33 Mass extinctions and ice ages	161
	3.34 Is there a cycle of mass extinctions?	162
	3.35 Diversification and recovery	163
	3.36 "Dead clades walking"	164
	3.37 The role of luck in the history of life	165
	3.38 Beyond the mass extinctions: The story of tropical rainforest diversity	166
	3.39 The Quaternary ice ages	169
	3.40 The ice ages and diversity in temperate-zone forests	173
	3.41 Ice ages may create as well as destroy temperate species	179
	3.42 What ice ages did to tropical rainforest diversity	180
	4 Hotspots and coldspots	184
	4.1 Geographical patchiness in species richness	184
	4.2 Hotspots	184
	4.3 Some examples of hotspots in species richness	185
	4.3.1 The big lakes of eastern Africa	185
	4.3.2 The western Cape of South Africa	187
	4.3.3 Lake Baikal in Siberia	188
	4.3.4 The mallee scrub of southwestern Australia	189
	4.3.5 The western edge of Amazonia	189
	4.4 What causes hotspots?	194
	4.4.1 The stable environments hypothesis	194
	4.4.2 The story of the Cape hotspot	195
	4.4.3 The story of Baikal	196
	4.4.4 The story of the African Rift Valley lakes	197
	4.4.5 The story of the southwest Australian mallee	199
	4.4.6 The story of the Amazon hotspots	199
	4.5 Some conclusions: how important is long-term stability for hotspots?	201
	4.6 Peculiarities of local ecology: Are these what it takes to set off a hotspot?	201
	4.6.1 What is peculiar about the Cape?	202
	4.6.2 What is special about the cichlids in African lakes?	203
	4.6.3 What could be peculiar about the western and central Amazonian forest hotspots?	204
	4.7 Do hotspots have more room for species, or have they just been given and retained more species?	207
	4.8 Coldspots	207
	4.9 Explanations for why diversity coldspots occur	208
	4.9.1 Island coldspots	208
	4.9.2 Island biogeography on land and in lakes	213
	4.9.3 Some experimental tests of MacArthur and Wilson's hypothesis	214
	4.10 The peninsula effect	216
	4.11 Bursts of speciation on islands	217
	4.12 Coldspots made through glacial extinctions	218
	5 The march of Cain: Humans as a destroyer of species	222
	5.1 The human species	222
	5.2 Humans and the extinction of other humans	223
	5.3 The secrets of our success over other human species	227
	5.4 Survival of species diversity during the Quaternary	228
	5.5 Yet mammals and birds have suffered a great wave of extinctions	231
	5.6 Africa, 150,000 years ago	231
	5.7 Australia, 45,000 years ago	232
	5.8 A second wave of extinction: the Americas and Eurasia	233
	5.9 Did climate change cause the extinctions on continents between 45,000 and 10,000 years ago?	235
	5.9.1 An Australian drought	236
	5.9.2 A thaw, then a freeze	236
	5.10 Coincidence of extinctions with human arrival-did the humans do it?	242
	5.10.1 When exactly did humans arrive?	242
	5.10.2 A "blitzkrieg" on animals in the Americas and Australia?	243
	5.10.2.1 Putting the overkill hypothesis to the test for North America	245
	5.10.2.2 The plausibility of overkill in South and Central America	246
	5.10.3 Modeling humans driving Quaternary megafauna extinct	247
	5.10.4 Problems in the dating: Did Australian animals really die out just as humans arrived?	250
	5.10.5 An explanation for the delay in Europe and the Americas: A "double-whammy" combination of climate change and over-hunting?	251
	5.10.6 Smaller animals tended to survive	253
	5.10.7 Fire-setting by humans in the Australian extinctions?	254
	5.10.8 Or was it a disease? Or meteorites?	255
	5.11 The wave of extinction spreads to islands	256
	5.11.1 The last mammoths: Wrangel and St. Paul Island	256
	5.11.2 Mediterranean islands	257
	5.11.3 Madagascar: lemurs and elephant birds	258
	5.11.4 Several thousand islands: the story of the Pacific	259
	5.11.5 New Zealand and the moas	261
	5.11.6 The Hawaiian islands and their birds	262
	5.11.7 Mauritius and the dodo	263
	5.11.8 St. Helena and its daisy trees	264
	5.11.9 Guam and its ground-nesting birds	265
	5.12 Why were island species so susceptible to extinction?	266
	5.13 Back to the mainland	267
	5.13.1 The great auk	268
	5.13.2 The passenger pigeon	269
	5.13.3 The Carolina parakeet	270
	5.13.4 The thylacine	271
	5.13.5 Yangtze River dolphin	272
	5.13.6 Cichlids in African lakes	272
	5.14 Current extinction, seen and unseen	273
	6 Knowing what is out there	276
	6.1 Nature's current totals	276
	6.2 Identifying new life forms-taxonomy and its challenges	279
	6.3 The stages in discovery of a new species	280
	6.3.1 Collection	281
	6.3.2 Identification	281
	6.3.3 Description and naming	282
	6.4 The uncertainties in current estimates of species richness	283
	6.5 The deep oceans: a big unknown	287
	6.6 Other tricks for estimating unknown species richness	288
	6.7 A bounty of nematodes?	289
	6.8 A plethora of mites?	289
	6.9 Estimating the unknown species richness of tropical insects	290
	6.10 So, how many types of arthropods are there?	294
	6.11 Cryptic diversity	294
	6.12 False species diversity: species complexes	296
	6.13 The hidden world of microbial diversity	297
	6.14 Nature still yields surprises	299
	6.15 The shadowy world of cryptozoology	299
	6.16 The twilight world of species richness	302
	7 The current threats	304
	7.1 The greenhouse effect and extinctions	305
	7.2 Species ranges changing under global warming	307
	7.2.1 Clues from the past	312
	7.2.2 Polar environments under global warming	313
	7.3 Mountains under climate change	314
	7.4 Coral reefs	315
	7.5 Global warming in the longer term	317
	7.6 Direct CO2 fertilization effects on plants	318
	7.7 The "other" direct CO2 effect, acidification of the oceans	324
	7.8 Introduced species	327
	7.8.1 Argentine ants and the fynbos	329
	7.9 The amphibian decline	329
	7.10 Tree diseases	331
	7.11 Habitat clearance	333
	8 Holding on to what is left	340
	8.1 Conserving habitat	340
	8.2 International biosphere reserves and world heritage sites	343
	8.3 Uncertainties about species richness: a problem for conservation	344
	8.4 Minimum viable population size	345
	8.5 Metapopulations: a complication to minimum viable population sizes	350
	8.5.1 The shapes and sizes of reserves	350
	8.6 How much do nature reserves lose? Relaxation extinction	354
	8.7 Active management of reserves	358
	8.8 Maintaining reserves in a changeable climate	360
	8.9 Aiding plant migration-planting	361
	8.10 Taxonomy as the arbiter of fate	363
	8.11 Botanic gardens and zoos	364
	8.12 Botanic gardens	366
	8.13 Seed and embryo banks	368
	8.14 In vitro storage of plant genetic material	370
	8.15 Rescue through genetic engineering and breeding, against introduced pests and diseases	371
	8.16 Back from the dead: Can we regain animals that have already gone extinct?	374
	8.17 Warning labels: alerting governments and the public of a species in trouble	376
	8.18 Laws	377
	8.19 Where we stand now	379
	References	381
	Index	395