Adaptive radiation

Adaptive radiation

[
13 finch species found on the Galápagos Archipelago, are thought to have evolved by an adaptive radiation that diversified their beak shapes to adapt them to different food sources.]

An adaptive radiation is a rapid evolutionary radiation characterized by an increase in the morphological and ecological diversity of a single, rapidly diversifying lineage. Phenotypes adapt in response to the environment, with new and useful traits arising.cite book
author = Schluter, D.
year = 2000
title = The Ecology of Adaptive Radiation
publisher = Oxford University Press
isbn = ] This is an evolutionary process driven by natural selection.

Causes of adaptive radiation

Innovation

The evolution of a novel feature may permit a clade to diversify by making new areas of morphospace accessible. A classic example is the evolution of a fourth cusp in the mammalian tooth. This trait permits a vast increase in the range of foodstuffs which can be utilized, with species able to specialize on feeding on a range of foodstuffs. The trait arose a number of times in different groups during the Cenozoic, and in each instance was immediately followed by an adaptive radiation.cite doi|10.1126/science.274.5292.1489] Birds find other ways to provide for each other, ie. the evolution of flight opened new avenues for evolution to explore, initiating an adaptive radiation. ["The Origin and Evolution of Birds" by Alan Feduccia (1999)]

Opportunity

Adaptive radiations often occur as a result of an organism arising in an environment with unoccupied niches, such as a newly formed lake or isolated island chain. The colonizing population may diversify rapidly to take advantage of all possible niches.

In Lake Victoria, an isolated lake which formed recently in the African rift valley, over 300 species of cichlid fish adaptively radiated from one parent species in just 15,000 years.

Adaptive radiations commonly follow mass extinctions: following an extinction, many niches are left vacant. A classic example of this is the replacement of the non-avian dinosaurs with mammals at the end of the Cretaceous, and of brachiopods by bivalves at the Permo-Triassic boundary..

ee also

*Evolutionary radiation - a more general term to describe any radiation
*Cambrian explosion - the most famous evolutionary radiation

Further reading

*Wilson, E. et al. "Life on Earth," by Wilson,E.; Eisner,T.; Briggs,W.; Dickerson,R.; Metzenberg,R.; O'brien,R.; Susman,M.; Boggs,W.; (Sinauer Associates, Inc., Publishers, Stamford, Connecticut), c 1974. Chapters: "The Multiplication of Species; Biogeography," pp 824-877. 40 Graphs, w species pictures, also Tables, Photos, etc. Includes Galápagos Islands, Hawaii, and Australia subcontinent, (plus St. Helena Island, etc.).
*Leakey,Richard. "The Origin of Humankind" - on adaptive radiation in biology and human evolution, pp. 28-32, 1994, Orion Publishing.
*Grant, P.R. 1999. The ecology and evolution of Darwin's Finches. Princeton University Press, Princeton, NJ.
*Mayer, Ernst. 2001. What evolution is. Basic Books, New York, NY.
*Kemp, A.C. 1978. A review of the hornbills: biology and radiation. The Living Bird 17: 105-136.

References


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Look at other dictionaries:

  • Adaptive Radiation — am Beispiel der Darwinfinken Schema der Radiation der Darwinfinken aus einem gemeinsamen Vorfahren …   Deutsch Wikipedia

  • adaptive radiation — n. 1. (Palaeontology) the evolutionary generation of multiple specialized life forms from one ancestral form, evidenced in the fossil record. The inverse of {extinction}. [PJC] …   The Collaborative International Dictionary of English

  • adaptive radiation — adaptive radiation. См. адаптивная радиация. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • adaptive radiation — n evolutionary diversification of a generalized ancestral form with production of a number of adaptively specialized forms * * * evolution from a generalized, primitive species to diverse, specialized species, each adapted to a distinct mode of… …   Medical dictionary

  • adaptive Radiation — adaptive Radiation, evolutive Fortentwicklung einer Ausgangsart in verschiedene Richtungen, d.h. Auffächerung in Arten, die an spezielle Umweltbedingungen (Nischen) angepasst sind. Ein Beispiel sind die Darwin Finken der Galapagos Inseln, die… …   Deutsch wörterbuch der biologie

  • adaptive radiation — n. Biol. the dispersal of, and adaptation to new environments by, a line of animals or plants, resulting in the evolution of divergent forms, often new species, specialized for surviving in the new habitats …   English World dictionary

  • adaptive radiation — Biol. the diversification of an ancestral group of organisms into a variety of related forms specialized to fit different environments or ways of life, each often further diversifying into more specialized types. [1900 05] * * * ▪ biology… …   Universalium

  • adaptive radiation — Evolutionary diversification of members of a single phyletic line into a series of different niches or adaptive zones …   Dictionary of invertebrate zoology

  • adaptive radiation — noun the development of many different forms from an originally homogeneous group of organisms as they fill different ecological niches • Hypernyms: ↑radiation …   Useful english dictionary

  • adaptive radiation — noun Date: 1902 evolutionary diversification of a generalized ancestral form with production of a number of adaptively specialized forms …   New Collegiate Dictionary

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