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In evolutionary ecology, an ecotype,〔Greek: ''οίκος'' = home and ''τύπος'' = type, coined by Göte Turesson in 1922〕 sometimes called ecospecies, describes a genetically distinct geographic variety, population or race within a species, which is adapted to specific environmental conditions. Typically, ecotypes exhibit phenotypic differences (such as in morphology or physiology) stemming from environmental heterogeneity and are capable of interbreeding with other geographically adjacent ecotypes without loss of fertility or vigor. 〔''Ecology: From individuals to ecosystems'' by Begon, Townsend, Harper, Blackwell Publishing 4th ed. (2006), p.5,6,7,8〕〔''Environmental Encyclopedia'' by Bortman, Brimblecombe, Mary Ann Cunningham, William P. Cunningham, Freedman - 3rd ed., p.435, "Ecotype"〕〔http://botanydictionary.org/ecotype.html〕 ==Range and distribution== Experiments indicate that sometimes ecotypes manifest only when separated by great spatial distances (of the order of 1,000 km). This is due to hybridization whereby different but adjacent varieties of the same species (or generally of the same taxonomic rank) interbreed, thus overcoming local selection. However other studies reveal that the opposite may happen, i.e., ecotypes revealing at very small scales (of the order of 10 m), within populations, and despite hybridization.〔 In ecotypes, it is common for continuous, gradual geographic variation to impose analogous phenotypic and/or genetic variation.〔 This situation is called cline. A well-known example of cline is the skin color gradation in indigenous human populations worldwide, which is related to latitude and amounts of sunlight.〔"Race". (2009). ''Encyclopædia Britannica''. Ultimate Reference Suite. Chicago: Encyclopædia Britannica.〕 But often the distribution of ecotypes is bimodal or multimodal. This means that ecotypes may display two or more distinct and discontinuous phenotypes even within the same population. Such phenomenon may lead to speciation and can occur if conditions in a local environment change dramatically through space or time.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ecotype」の詳細全文を読む スポンサード リンク
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