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Origin and Evolution of Life — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrigin and Evolution of Life4 Marks
Question
Distinguish between: Allopatric and Sympatric speciation.
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Answer

Allopatric speciationSympatric speciation
1. Allopatric speciation is the formation of a new species due to separation of a segment of population from the original population.1. Sympatric speciation is the formation of species within single population.
2. There is geographical barrier cutting across the species range during such speciation.2. There is no geographical isolation during sympatric speciation.
3. Allopatric speciation does not have physiological barrier.3. Sympatric speciation is due to physiological or reproductive isolating barrier.
4. Migration of individual are also helpful in allopatric speciation. E.g. African elephant and Indian elephant.4. Mutations are helpful in sympatric speciation. E.g. Cichlid fishes in Lake Victoria.

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