Question

multiple-choice question
which is the most likely explanation for the presence of 13 different finch species on
the galapagos islands today?

many years ago, a small population of a single bird species migrated to the islands and
evolved into the 13 species that live on the islands today.

many years ago, several different species of birds migrated to the islands and the 13
finch species that currently live there are the only species that survived.

each of the 13 species has migrated to the islands at different times over the years.

Explanation:

The concept of adaptive radiation (a process of evolution where a single ancestral species diversifies into multiple species, each adapted to different ecological niches) explains the Galapagos finches. The first option aligns with this: a single bird species migrated, then evolved into 13 species due to different environmental pressures on the islands. The second option's "several different species migrated" and third's "each species migrated at different times" don't fit the known evolutionary history of Galapagos finches (they originated from a single ancestor).

Answer:

A. Many years ago, a small population of a single bird species migrated to the islands and evolved into the 13 species that live on the islands today.