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Allopatric speciation (from Ancient Greek ἄλλος (állos) 'other' and πατρίς (patrís) 'fatherland') – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model [1]: 86 – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with gene flow.
For example, differential fusion implies greater postzygotic isolation among sympatric species, as this functions to prevent fusion between the species. However, Coyne and Orr found equal levels of postzygotic isolation among sympatric and allopatric species pairs in closely related Drosophila. [8]
One example of natural speciation is the diversity of the three-spined stickleback, ... a subform of allopatric speciation, new species are formed in isolated ...
A simplification of an allopatric speciation experiment where two lines of fruit flies are raised on maltose and starch media. Laboratory experiments of speciation have been conducted for all four modes of speciation: allopatric, peripatric, parapatric, and sympatric; and various other processes involving speciation: hybridization, reinforcement, founder effects, among others.
An example of gametic isolation involves the allopatric sea urchins have minimal bindin differences (bindin is a protein involved in the process of sea urchin fertilization, used for species-specific recognition of the egg by the sperm) and have insufficient barriers to fertilization.
For example, Albinaria land snails on islands in the Mediterranean [1] and Batrachoseps salamanders from California [2] each include relatively dispersal-limited, and closely related, ecologically similar species often have minimal range overlap, a pattern consistent with allopatric, nonecological speciation.
Evolution occurs continuously both in time and space, so that ecotypes or forms may qualify as distinct species in a few generations. [22] Begon, Townsend, and Harper use an illuminating analogy on this: ... the origin of a species, whether allopatric or sympatric, is a process, not an event. For the formation of a new species, like the boiling ...
Evidence for niche segregation as the result of reinforcement of reproductive barriers is especially convincing in those cases in which such differences are not found in allopatric but only in sympatric locations. For example, Kawano (2002) [69] has shown this for giant rhinoceros beetles in Southeast Asia. Two closely related species occur in ...