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Artificial Selection. Artificial Selection. Humans deliberately breed together organisms with desired traits. They provide an artificial “selection pressure”. This can lead to a great divergence from “wildtype” traits.
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Artificial Selection • Humans deliberately breed together organisms with desired traits. • They provide an artificial “selection pressure”. • This can lead to a great divergence from “wildtype” traits. • Traits that are non-adaptive in the wildtype may be expressed in the domestic version.
Importance of Domestication • Allowed for agriculture and hence to ability to settle down (as opposed to being nomadic). • Being able to settle allowed more time to develop technology. • It has allowed human to produce crops that: • produce a higher yield per area (e.g. larger grains, more per plant) • Are easier to process (e.g. seeds come away from stem more easily, wheat easy to separate from chaff). • Put more energy into building edible parts. • It has lead to the development of animals that: • Are easier to handle. • Provide transport or move goods. • Beast of burden (to help til the soil or grind grain) • Animals that can assist human (such as hunting dogs, sheep dogs etc.)
Examples of artificial selection • Domestication of: wolves, cats, horses, cows, chickens, pigeons etc. • Wheat, corn, mustard plants, apples, ornamental flowers. • Accidental artificial selection: bacteria that become resistant to antibiotics, smaller fish
