Biology / Unit 8 Bio 1693 short lesson, about 20 seconds
Allopatric Speciation: Dispersal and Vicariance
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The idea
Allopatric speciation occurs when geographic separation blocks gene flow, so populations diverge independently, whether by dispersal or by vicariance dividing a range.
In practice
A new lake dividing one rodent population, or a seed dispersing to a distant island, both start allopatric speciation by blocking flow.
Where people slip
Dispersal and vicariance both block gene flow, differing only in whether the population moved or the landscape divided.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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