Genetic divergence
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| - | [[Image:Blackface.jpg|thumb|200px|right|This reproduction of a [[1900]] [[minstrel show]] poster, originally published by the Strobridge [[Lithography|Litho]] Co., shows the transformation from [[white people|white]] to "[[blackface|black]]".]] | ||
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| - | '''Race''' is a classification system used to categorize [[human]]s into large and distinct [[population]]s or [[Group (sociology)|groups]] by [[anatomical]], [[cultural]], [[ethnic]], [[genetics|genetic]], [[geographical]], historical, [[language|linguistic]], [[religious]], or [[social group|social]] affiliation. First used to denote national affiliations, the term began to be used to relate to physical traits in the 17th century and promoted hierarchies favorable to differing ethnic groups. Starting from the 19th century the term was often used, in a [[Race (biology)|taxonomic sense]], to denote [[Genetic divergence|genetically differentiated]] human [[population]]s defined by [[phenotype]]. | ||
| - | ==See also== | + | '''Genetic divergence''' is the process in which two or more populations of an ancestral species accumulate independent genetic changes ([[mutations]]) through time, often after the populations have become [[Reproductive isolation|reproductively isolated]] for some period of time. In some cases, subpopulations living in ecologically distinct peripheral environments can exhibit genetic divergence from the remainder of a population, especially where the range of a population is very large (see [[parapatric speciation]]). The genetic differences among divergent populations can involve [[silent mutations]] (that have no effect on the [[phenotype]]) or give rise to significant [[Morphology (biology)|morphological]] and/or [[physiology|physiological]] changes. Genetic divergence will always accompany reproductive isolation, either due to novel adaptations via selection and/or due to genetic drift, and is the principal mechanism underlying [[speciation]]. |
| - | * [[Breed]] | + | |
| - | * [[Clan]] | + | |
| - | * [[Cultural difference]] | + | |
| - | * [[Ethnic nationalism]] | + | |
| - | * [[List of ethnic groups]] | + | |
| - | * [[Multiracial]] | + | |
| - | * [[Nationalism]] | + | |
| - | * [[Pre-Adamite]] | + | |
| - | * [[Race (fantasy)]] | + | |
| - | * [[Race (U.S. census)]] | + | |
| - | * [[Race and health]] | + | |
| - | * [[Race baiting]] | + | |
| - | * [[Race and ethnicity in censuses]] | + | |
| - | * [[The Races of Mankind|Races of Mankind]] for the [[Field Museum of Natural History]] exhibition by sculptor [[Malvina Hoffman]] | + | |
| - | * [[Racial discrimination]] | + | |
| - | * [[Racial stereotypes]] | + | |
| - | * [[Racial superiority]] | + | |
| - | * [[Racialization]] | + | |
| - | * [[Racism]] | + | |
| - | * [[Scientific racism]] | + | |
| - | * [[Social interpretations of race]] | + | |
| - | * [[The Race of the Future]] | + | |
| - | * [[The Race Question]] | + | |
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| + | On a molecular genetics level, genetic divergence is due to changes in a small number of [[gene]]s in a species, resulting in [[speciation]]. However, researchers argue that it is unlikely that divergence is a result of a significant, single, dominant mutation in a genetic [[locus (genetics)|locus]] because if that were so, the individual with that mutation would have zero [[fitness (biology)|fitness]]. Consequently, they could not reproduce and pass the mutation on to further generations. Hence, it is more likely that divergence, and subsequently [[reproductive isolation]], are the outcomes of multiple small mutations over evolutionary time. | ||
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Genetic divergence is the process in which two or more populations of an ancestral species accumulate independent genetic changes (mutations) through time, often after the populations have become reproductively isolated for some period of time. In some cases, subpopulations living in ecologically distinct peripheral environments can exhibit genetic divergence from the remainder of a population, especially where the range of a population is very large (see parapatric speciation). The genetic differences among divergent populations can involve silent mutations (that have no effect on the phenotype) or give rise to significant morphological and/or physiological changes. Genetic divergence will always accompany reproductive isolation, either due to novel adaptations via selection and/or due to genetic drift, and is the principal mechanism underlying speciation.
On a molecular genetics level, genetic divergence is due to changes in a small number of genes in a species, resulting in speciation. However, researchers argue that it is unlikely that divergence is a result of a significant, single, dominant mutation in a genetic locus because if that were so, the individual with that mutation would have zero fitness. Consequently, they could not reproduce and pass the mutation on to further generations. Hence, it is more likely that divergence, and subsequently reproductive isolation, are the outcomes of multiple small mutations over evolutionary time.
