Race (biology)

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This article is about the biological taxonomy term. For the sociological concept, see Race and society. For the anthropological term, see Race (human classification). For the technique in molecular biology, see Rapid amplification of cDNA ends.
Four different ecotypes, i.e. ecological races, of the species Physcomitrella patens, stored at the International Moss Stock Center

In biological classification, a race is an informal taxonomic rank, below the level of a species. It is used as a higher rank than strain, with several strains making up one race.[1][2]

Races may be distinct phenotypic populations within the same species, or they may be defined in other ways.[3] The term is also used for domesticated animals, see landrace.[3]

Races are defined according to any identifiable characteristic, and also by gene frequencies.[4] "Race differences are relative, not absolute".[4]

  • A physiological race, or forma specialis is a group of individuals that do not necessarily differ in morphology from other members of the species, but have identifiably different physiology or habits.[5] Parasitic species frequently have races that are adapted to different hosts.[5]
  • An ecological race is an ecotype, part of a species that is adapted to a different local habitat.

Race vs. subspecies[edit]

If the races are sufficiently different or if they have been tested to show little genetic connection regardless of phenotype, two or more groups/races can be identified as subspecies or another infraspecific rank, and given a name. According to Ernst W. Mayr, "a subspecies is a geographic race that is sufficiently different taxonomically to be worthy of a separate name."[6][7]

See also[edit]

References[edit]

  1. ^ Gotoh, T.; Bruin, J.; Sabelis, M.W.; Menken, S.B.J. (1993). "Host race formation in Tetranychus urticae: genetic differentiation, host plant preference, and mate choice in a tomato and a cucumber strain". Entomologia Experimentalis et Applicata 68 (2): 171–178. doi:10.1111/j.1570-7458.1993.tb01700.x. 
  2. ^ I. Buddenhagen (2009). "Understanding Strain Diversity in Fusarium oxysporum f. sp. cubense and History of Introduction of 'Tropical Race 4' To Better Manage Banana Production". ISHS Acta Horticulturae 828: 193–204. 
  3. ^ a b c Walker, P.M.B., ed. (1988). "Entry for Race". The Wordsworth Dictionary of Science and Technology. W. R. Chambers Ltd. and Cambridge University Press. 
  4. ^ a b c d Rieger, R.; Michaelis, A.; Green, M.M. (1968). A glossary of genetics and cytogenetics: Classical and molecular. New York: Springer-Verlag. ISBN 9780387076683. 
  5. ^ a b Walker, P.M.B., ed. (1988). "Entry for Physiological Race". The Wordsworth Dictionary of Science and Technology. W. R. Chambers Ltd. and Cambridge University Press. 
  6. ^ Ernst Mayr (1970). Populations, Species, and Evolution: An Abridgment of Animal Species and Evolution. Cambridge, Mass: Belknap Press. ISBN 0-674-69013-3. 
  7. ^ Ernst Mayr. The Biology of Race and the Concept of Equality. Daedalus, Winter 2002, pp.89-94.