sexual selection

(redirected from Male-male competition)
Also found in: Dictionary, Medical.
Related to Male-male competition: Female Choice

sexual selection:

see selectionselection.
In Darwinism, the mechanism of natural selection is considered of major importance in the process of evolution. Popular formulations sometimes envisage a struggle for existence in which direct competition for mates or for various factors in the environment (e.g.
..... Click the link for more information.
.

Sexual Selection

 

the particular form of natural selection distinguished by the evolutionary development of secondary sex characteristics. These characteristics include the bright nuptial plumage of many birds, including ducks and grouse, the dances of insects, the mating calls of birds, the fighting of male birds and mammals, the varied sound signals of males used to attract females, and the odoriferous glands of insects and mammals used for attracting the opposite sex. Prominent characteristics, such as coloration, develop chiefly in males. Females, especially during the reproductive period, are usually protected by appropriate behavior, coloration, and form.

The primary basis for sexual selection was the divergence in the identifying characteristics of males and females, which probably facilitated inbreeding of the same species and prevented crossbreeding with other species. Subsequently, individuals with more pronounced sexual characteristics attracted the opposite sex more easily and had the advantage in reproduction.

The ethological or behavioral mechanisms of isolation are partially affected by sexual selection. The course of sexual selection sometimes conflicts with other trends of natural selection. Genotypes that are preserved make reproduction more successful but do not increase the viability of the species as a whole. However, this does not justify contrasting sexual selection with natural selection or considering it an independent factor in evolution. Sexual selection was first suggested by C. Darwin in 1859 and later substantiated in 1871.

REFERENCES

Darwin, C. Proiskhozhdenie vidov putem estestvennogo otbora. In Soch, vol. 3. Moscow-Leningrad, 1939. (Translated from English.)
Darwin, C. Proiskhozhdenie cheloveka i polovoi otbor. In Soch., vol. 5. Moscow, 1953. (Translated from English.)
Shmal’gauzen, I. I. Problemy darvinizma, 2nd ed. Leningrad, 1969.

A. V. IABLOKOV

sexual selection

[¦seksh·ə·wəl si′lek·shən]
(evolution)
A special form of natural selection responsible for the evolution of traits that promote success in competition for mates.
References in periodicals archive ?
2007), suggesting that the activity of the males and male-male competition are important components of sexual selection in these types of breeding systems.
In other dimorphic beetles minor males avoid male-male competition by either mating earlier in the activity cycle or adopting satellite mating tactics (Eberhard 1982, Siva-Jothy 1987, Goldsmith 1987).
First, the males may bare enlarged femoral spines, perhaps used as weapons in male-male competitions (Sivinski 1978; Brock 1999).
Two mechanisms which contribute to the process of sexual selection are male-male competition and female choice.
He imagines that females are choosing the males who are the winners at male-male competition.
Martin and Bergmann (1996) argued that male-male competition may be occurring in situations where ".
But hierarchizing forces were at work contemporaneously; the overpopulation observed by David Herlihy intensified male-male competition, contributing to the rise of the patrilines noted by Herlihy, Christiane Klapisch-Zuber and Diane Owen Hughes.
Andersson likens contest or male-male competition to interference competition and mate choice to exploitative competition.
The influence of male mating history on male-male competition and female choice in mating associations in the blue crab, Callinectes sapidus (Rathbun).
Using multiple inbred lines, we measured the effect s of inbreeding on pre and post-mating success, in the absence and presence of male-male competition," said Gage.