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Related to darwinian evolution: Evolutionary Theory
the proposition that the phylogeny of all species is wholly ascribable to the combined effects of random variation (mutation) in genotypes of the members of a stock as a result of the operation of undirected accidents with consequences to their phenotypes and the operation of preferential (but by no means certain) survival of those resulting phenotypes most suited to survive in the contemporary environment. The proposed system survives largely because of genetic factors that avidly conserve the ontogeny of the stock.
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orthogenic evolutionAn obsolete term referring to the evolution of biota based on intrinsic changes in the organisms’ genetic constitution, which contrasts to environmentally dependent (bathmic) evolution.
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dar·win·i·an ev·o·lu·tion(dahr-win'ē-ăn ev-ŏ-lū'shŭn)
The proposition that the phylogeny of all species is wholly ascribable to random variation (mutation) in genotypes and the operation of preferential survival of those resulting phenotypes most suited to survive in the contemporary environment.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012