Preface ..................................................... ix
1 Discovery of a Unifying Principle ............................ i
A Brief History .............................................. 4
Detecting Character Displacement ............................ 10
Phenomena Mistaken for Character Displacement ............... 14
What Constitutes Character Displacement? Conflation of
Process and Pattern ......................................... 19
Reproductive Character Displacement versus Reinforcement .... 20
Terminology ................................................. 21
Box 1.1: Alternative Manifestations of Character
Displacement ....................................... 22
A Unifying Principle ........................................ 25
Box 1.2: Suggestions for Future Research .................... 26
Summary ..................................................... 27
Further Reading ............................................ 27
2 Why Character Displacement Occurs ........................... 29
Why Ecological Character Displacement Occurs ................ 30
Box 2.1: Alternative Models of Species Coexistence .......... 36
Box 2.2: Is Competitively Induced Plasticity Character
Displacement? ...................................... 44
Why Reproductive Character Displacement Occurs .............. 48
Box 2.3: Suggestions for Future Research .................... 53
Summary ..................................................... 54
Further Reading ............................................. 54
3 When Character Displacement Occurs .......................... 57
Facilitators of Character Displacement ...................... 58
Variation in the Expression of Character Displacement ....... 65
How Ecological and Reproductive Character Displacement
Facilitate Each Other ....................................... 69
How Ecological and Reproductive Character Displacement Can
Impede Each Other ........................................... 77
Box 3.1: Suggestions for Future Research .................... 78
Summary ..................................................... 78
Further Reading ............................................. 79
4 How Character Displacement Unfolds .......................... 81
Mechanisms of Divergence .................................... 82
Tempo and Mode of Character Displacement .................... 93
Summary .................................................... 102
Box 4.1: Suggestions for Future Research ................... 103
Further Reading ............................................ 104
5 Diversity and Novelty Within Species ....................... 105
How Intraspecific Character Displacement Works ............. 106
Intraspecific Character Displacement: Observational
Evidence ................................................... 108
Intraspecific Character Displacement: Experimental
Evidence ................................................... 110
Evolution of Alternative Phenotypes ........................ 111
Intraspecific Character Displacement and Species
Diversity .................................................. 126
Character Displacement Within Versus Between Species ....... 129
Summary .................................................... 130
Box 5.1: Suggestions for Future Research ................... 131
Further Reading ............................................ 131
6 Ecological Consequences .................................... 133
Evolution of the Niche ..................................... 134
Partitioning of Resources and Reproduction: A Reprise ...... 136
Box 6.1: Individual Variation and the Coexistence of
Species ........................................... 139
Community Organization ..................................... 143
Character Displacement and Darwinian Extinction ............ 146
Species Distributions and Geographic Mosaics ............... 150
Character Displacement and Species Ranges .................. 151
Summary .................................................... 153
Box 6.2: Suggestions for Future Research ................... 154
Further Reading ............................................ 155
7 Sexual Selection ........................................... 157
How Sexual Selection Works ................................. 159
How Character Displacement Affects Sexual Selection ........ 160
Implications of the Effects of Character Displacement on
Sexual Selection ........................................... 168
How Sexual Selection Affects Character Displacement ........ 174
A Cautionary Note: Process Versus Pattern .................. 175
Box 7.1: Suggestions for Future Research ................... 176
Summary .................................................... 176
Further Reading ............................................ 177
8 Speciation ................................................. 179
What Are Species? .......................................... 179
How Are Species' Boundaries Maintained? .................... 182
The Evolution of Isolating Mechanisms ...................... 183
Box 8.1: Selection and the Evolution of Reproductive
Isolation .................................................. 186
Character Displacement's Role in Speciation ................ 189
Summary .................................................... 202
Box 8.2: Suggestions for Future Research ................... 203
Further Reading .............................................203
9 Macroevolution ............................................. 205
Competition in the Fossil Record ........................... 207
Methods for Studying Macroevolution: Replaying the Tape
of Life .................................................... 211
Adaptive Radiation ......................................... 213
Evolutionary Escalation .................................... 224
Macroevolution: Red Queen or Court Jester? ................. 228
Summary .................................................... 229
Box 9.1: Suggestions for Future Research ................... 230
Further Reading ............................................ 230
10 Major Themes and Unsolved Problems ......................... 233
Major Themes of the Book 234 Some Unsolved Problems ........ 238
Summary .................................................... 242
References ................................................. 243
Index ...................................................... 291
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