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Developmental Selection
Developmental selection is selection that occurs on developmental units in an organism, such as cell lineages, embryos, and gametes or gametophytes. Generally, developmental selection is differentiated from natural selection because the targets of selection are internal to an organism contain the developmental units, rather than selection due to external environmental factors that favor specific phenotypes. However, in animals, developmental selection against offspring can manifest in the external environment, in which parents might select against offspring with developmental instabilities, or when offspring with deleterious malformations may not survive. Developmental selection in plants Selective embryo abortion A common form of developmental selection in plants is selective ovule abortion, where the maternal parent selects against unstable embryos. Abortion of low-viability offspring may be driven by either genetic factors or environmental stress. Developmental selection may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Charles Darwin popularised the term "natural selection", contrasting it with selective breeding, artificial selection, which in his view is intentional, whereas natural selection is not. Genetic diversity, Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits. The environment of a genome includes the molecular biology in the Cell (biology), cell, other cells, other individuals, populations, species, as well as the abiotic environment. Because individuals with certain variants of the trait tend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
