Chapter IV: Variation and Natural Selection

The law of persistence 61
The occurrence of variations 63
Application of the law of increase 76
Natural selection 77
Elimination and selection 79
Modes of natural elimination illustrated 80
Protective resemblance and mimicry 82
Selection proper illustrated 93
The effects of natural selection 95
Isolation or segregation 99
Its modes, geographical, preferential and physiological 99
Its effects 108
Utility of specific characters 110
Variations in the intensity of the struggle for existence 112
Convergence of characters 117
Modes of adaptation: Progress 119
Evolution and Revolution 120