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Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together.
The existence of limits in artificial selection experiments was discussed in the scientific literature in the 1940s or earlier. [1] The most obvious possible cause of reaching a limit (or plateau) when a population is under continued directional selection is that all of the additive-genetic variation (see additive genetic effects) related to that trait gets "used up" or fixed. [2]
Sexual selection in humans concerns the concept of sexual selection, introduced by Charles Darwin as an element of his theory of natural selection, [1] as it affects humans. Sexual selection is a biological way one sex chooses a mate for the best reproductive success. Most compete with others of the same sex for the best mate to contribute ...
Sexual selection creates colourful differences between sexes in Goldie's bird-of-paradise.Male above; female below. Painting by John Gerrard Keulemans.. Sexual selection is a mechanism of evolution in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex ...
Therefore, only those with the highest index score are selected for breeding via artificial selection. This method has advantages over other methods of artificial selection, such as tandem selection, in that you can select for traits simultaneously rather than sequentially. Thereby, no useful traits are being excluded from selection at any one ...
Humans have altered the genomes of species for thousands of years through selective breeding, or artificial selection [20]: 1 [21]: 1 as contrasted with natural selection. More recently, mutation breeding has used exposure to chemicals or radiation to produce a high frequency of random mutations, for selective breeding purposes. Genetic ...
Mouse from the Garland selection experiment with attached running wheel and its rotation counter. In 1993, Theodore Garland, Jr. and colleagues started a long-term experiment that involves selective breeding of mice for high voluntary activity levels on running wheels. [44] This experiment also continues to this day (> 105 generations). Mice ...
Darwin described natural selection as being analogous to the artificial selection practised by animal breeders, and emphasised competition between individuals; Wallace drew no comparison to selective breeding, and focused on ecological pressures that kept different varieties adapted to local conditions.