Speciation refers to the evolutionary process of genesis of the new species. The formation of these new and distinct species from the existing species occurs in two different ways Allopatrically and Sympatrically. Allopatric speciation occurs mainly due to the geographic isolation while Sympatric speciation happens within a population, by appearance of reproductive limitations or barriers.
|Allopatric Speciation||Sympatric Speciation|
|Geographic isolation needed||Yes||No|
|Major differentiation mechanism||Natural selection||Polyploidy|
|Speed of creation of new species||Slow||Autopolyploidy – fast; allopolyploidy – slow|
|Are they Common in nature?||Yes||Yes – in plants|
|The Examples||Darwin’s Finches; squirrels in the Grand Canyon||Cultivated corn, wheat and tobacco|
This type of speciation occurs when biological populations of the existing species get separated from each other. The separation leads them to interfere with genetic interchange. The isolation is caused by geographical barriers like rivers, mountains etc. The separation greatly reduces the chances of interbreeding between the populations. The changes in population enable them to adapt to the new environment. The reproductive separations detach two populations into two species. Allopatrical separation is regarded as the most common form of speciation.
This type of speciation occurs when there is a formation of two new and distinct species which develop from a single existing ancestral species. This formation evolves while dwelling in the same geographical area. Here the biological populations are not geographically isolated. This type of speciation often occurs through polyploidy. A diploid individual and a tetraploid individual cannot interbreed together and it leads to a reproductive separation. Sympatric Speciation occurs rarely and it is commonly found in plants rather than animals.
The above article furnishes the authentic information about the Allopatric Speciation and Sympatric Speciation. It enables one to draw the exact differences between both the speciation.