ACKNOWLEDGEMENTS ................................................. v
CONTENTS ......................................................... vi
LIST OF TABLES ................................................... viii
ABSTRACT ......................................................... ix
INTRODUCTION ..................................................... 1
The Idea of Modifier Genes ................................... 1
The Results of Modifier Theory ............................... 4
The Approach of This Thesis .................................. 8
CHAPTER 1: SELECTION AND TRANSFORMATION ......................... 11
Transformation-Selection Balances ............................ 14
The Nature of Types That Can Evolve .......................... 15
The Evolution of Transformations ............................. 17
Formalizing Transformation Processes ......................... 18
Examples of Transformation Processes ......................... 25
Situations Rendering Perfect Transmission Unattainable ....... 32
Formalizing Selection......................................... 33
CHAPTER 2: EVOLUTION UNDER SELECTION AND TRANSFORMATION ......... 36
The Recursions on the Frequencies of Types ................... 37
Basic Properties of the Recursions ........................... 49
Additional Aspects of Evolution
Under Selection and Transformation ......................... 65
Transformation and "Units of Selection" Arguments ............ 81
Summary ...................................................... 82
CHAPTER 3: THE EVOLUTION OF TRANSFORMATIONS ..................... 84
The Selective Forces on Transformation Types ................. 86
The Nature of Variations in Transformations .................. 89
The Evolution of Transformation Types
Under Pure Branching Descent ............................... 94
The Evolution of Transformation Types
Under Pair-Mating Descent .................................. 106
The Diploid Modifier Gene Model ........................ 107
Intragenomic Transformation ...................... 109
Migration Modifiers .............................. 178
A Model for Selection on Sexual Reproduction ........... 199
A Model for Modifiers in Cultural Transmission ......... 203
The Strength of Selection on Modifiers and
the Effect of Pleiotropy ................................... 207
Conclusions .................................................. 209
CHAPTER 4: DISCUSSION ........................................... 213
Speculations in the Literature ............................... 213
Limitations of the Analysis .................................. 215
On the Uses of the Term "Modifier" ........................... 216
Underlying Homology Between Phenotype Distribution Models
and Modifier Models ........................................ 218
The Fitness Load Principle ................................... 223
Implications of the Principle of Partial Control ............. 225
LIST OF REFERENCES ............................................... 229