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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.
Examples are the cabbage varieties, maize, or the large number of different dog breeds. The power of human breeding to create varieties with extreme differences from a single species was already recognized by Charles Darwin. In fact, he started out his book The Origin of Species with a chapter on variation in domestic animals. In this chapter ...
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]
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]
Humans have used artificial selection for thousands of years in the domestication of plants and animals. [4] More recently, such selection has become a vital part of genetic engineering, with selectable markers such as antibiotic resistance genes being used to manipulate DNA in molecular biology.
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.
Artificial reproduction is the re-creation of life by other than the natural means and natural causes. It involves building of new life following human plans and projects. Examples include, artificial selection, artificial insemination, in vitro fertilization, artificial womb, artificial cloning, and kinematic replication.
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 ...