Question

. A population of plants of one species is living in a large desert. Some of the dunes are higher than others and over time some of the plants end up with long roots and others with short roots, each group being adapted to the height of the dunes they live in. During this time they also have changes in their pollen structure and the one group can no longer reproduce with members of the other group. The best way to describe this situation is

a. allopatric speciation by vicariance.

b. allopatric speciation by dispersal.

c. disruptive selection followed by sympatric speciation

d. gene flow between the two groups in a hybrid zone.

Answer 1

Option a is the correct answer.

This is an example for allopatric speciation by vicariance.

Isolation by vicariance occurs when a population that is already widely distributed is divided by the appearance of a barrier.Here dunes is the barrier.