Sympathy , or sympathy (from the Greek. Sýn - together and patris - the birthplace) is a method of speciation in which the emergence of new species occurs in populations with overlapping or coincident habitats [1] . Populations living in the same territory are called sympatric. Non-crossing species that coexist within the same region are sympathetic. This term is used to denote two different situations: in the first situation, populations coexist genetically, but not ecologically, and in the second, they coexist both genetically and ecologically [2] . The first situation is called related sympathy, the second - biotic sympathy [2] .
The opposite case, speciation in populations with non-overlapping habitats, is called allopathy [1] .
The emergence of sympathy is possible only under the condition that the two forms coexisting within the general area or part thereof do not mix. In some cases, the emergence of sympatric species is the result of allopatric speciation with subsequent resettlement of individuals of one species within the range of another species.
Related Sympathy
It occurs when two or more habitats are directly adjacent to each other, and between them there are areas that separate habitats throughout vast geographical areas. For example, in the savannah there is an alternation of woodlands with sections of open meadows; in the mountains, various sections of altitudinal zoning are arranged in the form of concentric rings. The populations inhabiting areas bordering each other, but at the same time differing according to different criteria, are within their ranges, so that from a spatial point of view, crossing between them is possible. Such populations are called contiguous sympatric . Adjacent sympathy is usually characteristic of ecological races.
Biotic Sympathy
It is possible when two or more populations live in the same locality. In this case, there is not only overlapping of the zones within which the gametes of the representatives of the populations are dispersed, but also their contacts with each other during the period of the non-reproductive stage of life cycles. Such populations are called biotically sympatric .
Notes
- ↑ 1 2 Timofeev-Resovsky N.V. , Yablokov A.V., Glotov N.V. , Essay on the doctrine of the population, M., 1973; Mayr E., Populations, Species, and Evolution, trans. from English., M., 1974
- ↑ 1 2 Vern Grant. The evolution of organisms. - Moscow: Mir, 1980 .-- 408 p.