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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]
Tandem selection is a method of artificial selection in which useful traits are selected for sequentially. [1] For instance, one could select for both increased milk yield and increased milk fat content in cows via tandem selection by first selecting those with the best of one trait, production of high milk yield, and then when that trait is at a satisfactory level, by starting to select for ...
Heck cattle were bred in the 1920s to resemble the aurochs.. Breeding back is a form of artificial selection by the deliberate selective breeding of domestic (but not exclusively) animals, in an attempt to achieve an animal breed with a phenotype that resembles a wild type ancestor, usually one that has gone extinct.
The red junglefowl (Gallus gallus), often believed to be an ancestor of the domestic chicken.. Most animals are tuned to modern life by artificial selection. This is either due to the pressure of early hunter-gatherers' attempts to stabilise the food supply, which resulted in the existence of domesticated farm animals, or domestication of pets which are useful to humans. [2]
The process of artificial selection has had a significant impact on the evolution of domestic animals. For example, people have produced different types of dogs by controlled breeding. The differences in size between the Chihuahua and the Great Dane are the result of artificial selection.
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 ...
Human-directed genetic manipulation began with the domestication of plants and animals through artificial selection in about 12,000 BC. [1]: 1 Various techniques were developed to aid in breeding and selection. Hybridization was one way rapid changes in an organism's genetic makeup could be introduced. Crop hybridization most likely first ...