Artificial selection - conscious and unconscious selection by man of individuals of plants, animals and microorganisms with the most useful for him traits.
The selection by man of the most economically valuable animals and plants for the purpose of their further breeding. In contrast to natural selection, which acts in the direction of adaptation of organisms to the environment, artificial selection is aimed at fixing individual traits useful for humans, while other traits important for the viability of organisms may be lost.
Unconscious artificial selection has existed since antiquity, when man began to domesticate animals and cultivate plants. Over time, techniques and methods of conscious, methodical artificial selection were developed. Its theory was created by C. Darwin.
Two main forms of selection are used in breeding. In mass artificial selection, individuals with desirable traits for a breed or variety are retained, and the rest are culled. Such selection by external traits (phenotype) can be repeated, since hereditary stability (homogeneity) is not achieved. In individual artificial selection, individuals are selected not only for the presence of desirable traits, but also for their ability to transmit them to offspring, i.e. in this case selection is also based on genotype. Individual selection uses various types of crosses, including inbreeding, leading to the creation of genetically homogeneous pure lines.
Forms of artificial selection:
Unconscious - in this form of selection, the best specimens are retained without setting a definite goal.
Methodical - a person purposefully approaches the creation of a new breed or variety by setting certain objectives. Methodical selection is a creative process that produces faster results than unconscious selection. This method of breeding is based on the variability of traits, their inheritability and selection. Methodical in turn is divided into Single and Multiple. In turn, single selection is selection in one generation. Multiple selection is selection during a number of generations for the same traits until a significant improvement of the required trait is achieved.
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