Heterotopia(redirected from heterotopous)
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a change in position and site of development of an organ in the course of individual ontogeny in animals; one of the methods of evolutionary rearrangement of an organism.
Heterotopia is the result either of the migration of cells from one germ layer to another, of the displacement of cells within a given germ layer, or of the secondary displacement of organs. Examples of heterotopia include the displacement of the heart to the thoracic cavity in birds and mammals (near the head in fish and amphibians) and the translocation of the forelegs to the rear in higher vertebrates (in comparison to the thoracic fins offish). The term “heterotopia” was introduced by the German naturalist E. Haeckel in 1874 to designate disturbances of the phylogenetically determined spatial sequence of the stages of ontogeny. It was subsequently shown that heterotopia does not fit into Haeckel’s interpretation of cenogenesis.
REFERENCESSevertsov, A. N. Morfologicheskie zakonomernosti evoliutsii. Moscow-Leningrad, 1939.
Miiller, F. and E. Haeckel. “Osnovnoi biogeneticheskii zakon.” Izbr. raboty. Moscow-Leningrad, 1940.
E. N. MIRZOIAN