International A Level Biology / Environment and climate change

Allopatric and sympatric speciation revision notes

Edexcel International A Level Biology (YBI11), chapter 16: Environment and climate change, specification point 5.24. Part of the full course.

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Speciation is the formation of new species when gene flow between groups is reduced and they become unable to produce fertile offspring together. Allopatric speciation follows geographical separation, while sympatric speciation happens in the same area.

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