Information AboutSympatric Speciation |
| CATEGORIES ABOUT SYMPATRIC SPECIATION | |
| speciation | |
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Sympatric Speciation is the genetic divergence of multiple populations (from a single parent species) inhabiting the same geographic region; such that those populations become different species. Etymological ly, sympatry is derived from the roots sym- (meaning same, alike, similar, or fellow) and -patry (meaning homeland or fatherland). Sympatry is one of four theoretical models for the phenomenon of Speciation . In complete contrast to Allopatry , species undergoing sympatric speciation are not geographically isolated by, for example, a mountain or a river. Debated almost since the beginning of popular evolutionary thought, sympatric speciation is still a highly contentious issue. By 1980 the theory was largely unfavourable given the void of empirical evidence available, and more critically the conditions scientists expect to be required. Ernst Mayr , one of the foremost thinkers on evolution, completely rejected sympatry outright, ushering in a climate of hostility towards the theory. Since the 1980s , a more progressive ideology has been adopted. While still debatable, well documented empirical evidence now exists, and the development of sophisticated theories incorporating multilocus genetics have followed. A number of models have been proposed to account for this mode of speciation. The most popular, Disruptive Speciation , was first put forward by John Maynard Smith in 1962 . Maynard Smith suggested that Homozygous individuals may, under particular environmental conditions, have a greater fitness than those with Allele s Heterozygous for a certain trait. Under the mechanism of Natural Selection , therefore, homozygosity would be favoured over heterozygosity, eventually leading to speciation.
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