Species Concept
Over the last few decades the Biological Species Concept (BSC) has become predominately the dominant species definition used. This concept defines a species as a reproductive community.
This though has had much refinement through the years. The earliest precursor to the concept is in Du Rietz (1930), then later Dobzhansky added to this definition in 1937.But even after this the definition was highly restrictive. The definition of a sp ecies that is accepted as the Biological species concept was founded by Ernst Mayr (1942); "..groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups" However, this is a definition on what happens in nature. Mayr later amended this definition to include an ecological component; "..a reproductive community of populations (reproductively isolated from others) that occupies a specific niche in nature The BSC is greatly accepted amongst vertebrate zoologists & entomologists. Two reasons account for this .Firstly these are the groups that the authors of the BSC worked with. (Mayr is an ornithologist & Dobzhansky has worked mainly with Drosophila). More importantly Sexual reproduction is the predominate form of reproduction in these groups. It is not coincidental that the BSC is less widely used amongst botanists. Terrestrial plants exhibit much more greater diversity in their mode of reproduction than vertebrates and insects.
There has been many criticisms of the BSC in its theoretical validity and practical utility. For example, the application of the BSC to a number of groups is problematic because of interspecific hybridisation between clearly delimited species.(Skelton).
It cant be applied to species that reproduce asexually ( e.g Bdelloid rotifers,eugelenoid flagellates ).Asexual forms of normally sexual organisms are also known. Prokaryotes are also left out by the...
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