The Ant and the Peacock is about two disagreements between Darwin and Wallace: altruism and sexual selection.
In the study of sexual selection that individual factor was passed over very lightly.
If it were not so there could be no sexual selection, nor any social organization.
Otherwise, what becomes of the accepted doctrine of sexual selection?
The third factor of evolution which we have considered is sexual selection.
Ripley (Races of Europe, pp. 49, 202) attaches much importance to the sexual selection founded on a tendency of this kind.
If so, sexual selection must be conducive to the stability of species.
The other Darwinian factor in evolution is sexual selection.
But the results of sexual selection are by no means perfect.
Such are the main lines of evidence in favour of the theory of sexual selection.
sexual selection n.
Selection that is driven by the competition for mates and that is considered an adjunct to natural selection.
|sexual selection |
The process by which certain organisms produce more offspring by mating more frequently than other organisms of the same sex and thereby ensure the survival of more of their genetic traits. Sexual selection is a form of natural selection in which organisms are competing not for food or other resources in the environment but for mates. The development of size difference between males and females in mammals and birds, in which the greater strength (and often aggressiveness) of larger males allows them to have greater success mating, is seen as a consequence of sexual selection. The development of secondary sex characteristics, such as colored feathers in male birds or large antlers in male deer, which are attractive to the opposite sex as signs of fitness but are not directly involved in reproduction is also attributed to sexual selection. These features are often disadvantageous to the organism's survival—the colored feathers make the male bird more visible to predators, for instance—but can provide the organism with a competitive advantage over rivals in mating. The theory of sexual selection was first proposed by Charles Darwin in The Origin of Species.
In evolution, the selection of a mate based on secondary sex characteristics. Sexual selection is thought to lead distinct differences in the appearance of the two sexes within a species. For example, the tail of the male peacock may be the result of sexual selection.