allopatric speciation

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allopatric speciation

A process in which two or more populations of the same (but geographically separated and non-interbreeding) species become less similar to each other over time, through mutation or survival advantages of different traits in differing environments, and eventually become distinct species.
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allopatric speciation

the genetic differentiation of populations which are geographically separate to the point where they become separate SPECIES.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
In this sense, we can infer that the current distribution patterns of the aquatic insects in Southern Brazil wetlands are determined mainly by vicariant events, and not by uncorrelated individual dispersions.
The parameters varied in the model's gene flow regimes under isolation by distance and the timing of vicariant events in sundered populations.
By definition, allopatric and microallopatric divergence require long-term extrinsic barriers to dispersal (vicariant events).
Consider now effects of a vicariant event that interrupts gene flow at one point in the cline, but that leaves all populations on either side of this point still exchanging migrants.
These divergence date estimates are at least in part consistent with Haffer's (Haffer 1969; Simpson and Haffer 1978) hypothesis that most geographically differentiated species are the result of Pleistocene climatic vicariant events, although probably not the most recent cycle of glaciation (21,000-13,000 ybp; van der Hammen 1974).
For example, if two widespread species were fragmented by a vicariant event, one would eventually expect that haplotypes in each species would be monophyletic on each side of the isolating barrier.
An ancestral vicariant event in the Pacific must have caused early divergence of these two clades.
However, the possibility exists that vicariant events may have contributed to the patterns discerned: a secondary contact zone gives identity to oregonensis and platensis north and west of Lassen Peak, there is a region of reduced gene flow on both sides of the Wagner Ridge population (27) in the central Sierra Nevada that might be interpreted as another region of secondary contact, and there is an apparent geographic gap (Bob's Gap) between croceater and klauberi.
distribution is inferred to be wide (= sum of all areas, ABcDEFG) with the occurrence of subsequent vicariant events. Sympatric distributions (overlapping) between terminal taxa and between clades were resolved by assuming at least 10 ad hoc events, however, the DIVA algorithm cannot correctly distinguish whether dispersion or dispersal occurred, i.e., simple range expansion or a true dispersal process.
These subregions suggest specific microhabitats for the benthic hydroid fauna of the SO that may be derived from dispersal or vicariant events.