Question

Suppose there was a type of primate called the Buttermouth monkey that lives on a remote island in the South Pacific. There are two types of Buttermouth monkeys, the Spotted Buttermouth and the Banded Buttermouth. The two types of monkeys have distinct fur coloring, have differing diets, and live in habitats on opposite sides of the island. Prior to a large volcanic eruption in the center of the island, the Spotted and Banded Buttermouths were able to mate and produce fertile offspring. However, in recent years successful matings became very rare and have not been observed in over two decades. What biological process might explain this observation

Answer 1

The biological process that might explain this observation is speciation. Speciation is the process by which populations evolve to become distinct species. In this case, the Spotted and Banded Buttermouths have become so different from each other that they are no longer able to mate and produce fertile offspring.