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Natural Selection
Natural selection and evolution
Term | Definition |
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Evolution | the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth. |
Natural selection | the process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin and is now believed to be the main process that brings about evolution. |
Charles Darwin | Darwin, Charles. A British naturalist of the nineteenth century. He and others developed the theory of evolution. This theory forms the basis for the modern life sciences. Darwin's most famous books are The Origin of Species and The Descent of Man . |
fitness | the condition of being physically fit and healthy. |
variability | lack of consistency or fixed pattern; liability to vary or change. |
inheritability | The process of genetic transmission of characteristics from parent or ancestor to offspring. b. A characteristic so inherited. |
artificial selection | Artificial selection is the intentional breeding of plants or animals. It means the same thing as selective breeding and is an ancient method of genetic engineering. |
adaptation | the action or process of adapting or being adapted. |
structural adaptation | Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. |
mimicry | the action or art of imitating someone or something, typically in order to entertain or ridicule. |
camouflage | the disguising of military personnel, equipment, and installations by painting or covering them to make them blend in with their surroundings. |
fossil record | A fossil record is a group of fossils which has been analyzed and arranged chronologically and in taxonomic order. Fossils are created when organisms die, are incased in dirt and rock, and are slowly replaced by minerals over time. |
homologous mixture | having the same relation, relative position, or structure. |
analogous structure | analogous. ... Analogous things can be compared to each other, so a near synonym is the adjective comparable. |
vestigial structure/ organ | vestigial-structure. Noun. (plural vestigial structures) (biology) A structure in an organism that has lost all or most of its original function in the course of evolution, such as human appendixes. |
embryol | An embryo is an early stage of development of a multicellular diploid eukaryotic organism. |
gene pool | the stock of different genes in an interbreeding population. |
genetic drift | variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce. |
allele/gene frequency | Allele frequency, or gene frequency, is the relative frequency of an allele (variant of a gene) at a particular locus in a population, expressed as a fraction or percentage. |
stabilizing selection | Allele frequency. ... Specifically, it is the fraction of all chromosomes in the population that carry that allele. Microevolution is the change in allele frequencies that occurs over time within a population.. |
bottleneck effect | A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events (such as famines, earthquakes, floods, fires, disease, or droughts) or human activities (such as genocide). |
founder effect | the reduced genetic diversity which results when a population is descended from a small number of colonizing ancestors. |
fossil | the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock. |
sepciation | the formation of new and distinct species in the course of evolution. |
directional selection | In population genetics, directional selection is a mode of natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype. |
disruptive selection | Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. |