The evolution of parental care/ T.H. Clutton-brock

Parental Care and Competition for Mates
1.1 Parental Care and Sexual Selection 3
1.2 Parental Care And Competition for Mates 5
1.3 The Evolution of Parental Care 7
1.4 Definitions of Parental Care and Parental
Investment 8
Forms of Parental Care
2.1 Introduction 13
2.2 Preparation of Nests, Burrows, or
Territories 13
2.3
Production of Gametes 14
2.4 Care of Eggs 15
2.5 Care of Young without Provisioning from
Sources outside the Egg
Provisioning Young before Hatching or Birth
Provisioning Young after Hatching or Birth
2.8 Care of Offspring after Nutritional
Independence
Social Assistance to Mature Offspring
Summary
The Costs of Breeding
Introduction 31
3.2 Parental Expenditure 32
Correlations between Components
of Fitness 34
3.4 The Limitations of Phenotypic
Correlations
3.5 Experimental Manipulation of Parental
Expenditure
Negative Genetic Correlations between
Fitness Components 43
Propagule Size
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4.1 Introduction 49
4.2 How Large Should Propagules Be? 49
4.3 How Much Time Should Be Spent
in the Egg? 54
4.4 Constraints on Propagule Size 57
4.5 Variation In Propagule Size 61
4.6 Egg Size and Parental Care 65
4.7 Is There a Single Optimal Propagule Size
or an Optimal Range of Variation? 66
4.8 Summary 68
Viviparity
5.1
Introduction
5.2
Viviparity among Invertebrates
5.3
Viviparity In Fish
5.4
Viviparity in Amphibia
5.5 Viviparity in Reptiles
5.6 On the Absence of Viviparity in Birds
5.7
Viviparity in Mammals
6 Incubation, Gestation, and Lactation
6.1 Introduction 85
6.2 Body Size and the Duration of
Development Periods 88
6.3 Incubation 89
6.4 Gestation and Age at Weaning 90
6.5 Lactation 92
6.6 Milk Composition 94
6.7 Summary 99
7 Parental Care in Ectotherms
7.1 Introduction
7.2
The Evolution of Parental Care by
Males and Females
7.3
The Maintenance of Parental Care by
Males and Females
7.4
Parental Care In Invertebrates
7.5
Parental Care in Fish
Parental Care in Amphibia
Parental Care in Reptiles
Summary
Parental Care in Birds and Mammals
8.1 Parental Care and Breeding Systems in
Birds and Mammals 131
8.2 Models of Parental Care 140
8.3 Why Do Males Help in Biparental
Species? 140
8.4 Why Don't Males Always Assist with
Parental Care?
145
8.5 Why Do Males Agree to Being the Only
Care-giver in Some Monogamous Species? 146
8.6 Why Do Males Agree to Polyandry? 147
8.7 Why Are Males Responsible for All Care
in Some Polygynous Birds? 150
8.8 Summary 151
Parental Tactics 1: Variation in Care in
Relation to Benefits
9.1 Introduction 155
9.2 Parental Care and Parent-Offspring
Relatedness 157
9.3 Parental Care and Brood Size 158
9.4 Parental Care and Offspring Age 161
9.5 Parental Care and Offspring Quality 164
9.6 Brood Reduction 165
9.7 Brood Desertion 170
9.8 Summary 172
Parental Tactics 2: Variation in Care in
Relation to Costs
10.1 Introduction 175
10.2 Parental Investment and Resource
Availability 175
10.3 Reduced Reproductive Success in Young
Breeders: Restraint or Constraint? 176
10.4 Reproductive Value and Terminal
Investment 178
10.5 Parental Investment by Males and
Access To Mating Partners 182
10.6 Parental Investment and Conflicts of
Interest between Care-givers 183
10.7 Parental Decision Rules 188
10.8 Summary 190
Parent-Offspring Conflict
11.1 Introduction 193
12
X • CONTENTS
11.2 Parent-Offspring Conflict in Theory 193
11.3 Parent-Offspring Conflict in Practice:
Predictions 201
11.4 Summary 206
Parental Investment in Sons and
Daughters
12.1 Introduction 209
12.2 Does Parental Expenditure Have a Greater
Effect on Fitness in Males or Females? 209
12.3 Parental Expenditure and Sex Differences
in Early Growth 213
12.4 Energy Expenditure on Sons and
Daughters 215
12.5 Reproductive Costs of Sons and
Daughters 218
12.6 Sex Allocation or Differential Extraction? 221
12.7 Sex Differences in Parental Investment
and the Population Sex Ratio 223
12.8 Summary 226
13 Sex Ratios and Differential Juvenile
Mortality
13.1 Introduction 229
13.2 Sex Ratio Variation at Hatching or Birth 232
13.3 Sex Differences in Juvenile Mortality 242
13.4 Summary 252
14 Conclusions
14.1 Introduction 255
14.2 What Are the Benefits and Costs of
Parental Care? 255
14.3 Why Does the Extent of Parental Care
Vary so Widely among Species? 257
14.4 why Do Only Females Care for Eggs and
Young in Some Species. Only Males in
Others, and Both Parents in a Few? 258
14.5 To What Extent Is Parental Care Adjusted
to Variation in Its Benefits to Offspring
and Its Costs to Parents? 261
14.6 How Do Parents Divide Their Investment
between Sons and Daughters? 262
14.7 Prospects 263