You examine four forested Caribbean islands. Each has four species of Anolis lizard that use four ecological niches (for a total of 16 species). On each island, one species exclusively occupies either the ground, tree trucks, limbs and branches, or the smallest twigs and leaves. Phylogenetic analysis shows that the species on each island form their own monophyletic groups. Which is the best explanation for this pattern?

Each island was founded by a colonizer, perhaps from a mainland, and divided up ecological niche space as they diversified into the four species present.

Explanation:

Phylogenetic analysis is the study of determining the evolutionary relationships of species. Phylogenetic is important because it makes us understand how different species evolves.

In the given context, four species of the lizards in the four Caribbean Island are descended from the four separate common ancestor of four different species.

Thus it can be concluded that each of the four Caribbean Island was founded by a lizard species colonized to that area or might have come from the main land and played an important role in the ecological niche as they varied and expand into present four species.

Hence the answer is - --

Each island was founded by a colonizer, perhaps from a mainland, and divided up ecological niche space as they diversified into the four species present.