The first people to explore the Galapagos Islands noticed that the finches there are different species than the finches living on the nearby mainland.

Question

Which most likely caused this example of speciation?

A. Unhealthy conditions on the islands caused severe mutations.

B. The birds had different mating seasons and could not interbreed.

C. Adaptation stopped on the mainland but continued on the islands.

D. The water between the mainland and islands prohibited interbreeding.

Answer 1

The most likely cause of the speciation of finches in the Galapagos Islands compared to those on the nearby mainland is:

D. The water between the mainland and islands prohibited interbreeding.

This option highlights the geographical barrier that would prevent the finches from mating between the mainland and the islands, leading to reproductive isolation. Over time, this isolation allows the finches on the islands to adapt to their unique environments, ultimately resulting in the development of different species.