Two species encounter rarely because they occupy different habitats, even though not physically blocked. This is an example of which isolation?

Two species encounter rarely because they occupy different habitats, even though not physically blocked. This is an example of which isolation?

• A. Prezygotic Barrier
• B. Postzygotic Barrier
• C. Mechanical Isolation
• D. Ecological Isolation

Answer: (D)

The main idea is that species can be reproductively isolated simply by occupying different environments, which reduces chances of encountering and mating. This situation is ecological isolation (often called habitat isolation) because the two species live in distinct habitats and rarely meet, preventing gene flow before any mating occurs. It’s a prezygotic barrier since the separation happens before fertilization, due to lack of contact. The other options don’t fit: postzygotic barriers occur after mating (hybrid inviability or sterility), and mechanical isolation involves incompatible reproductive structures rather than differences in habitat.

The main idea is that species can be reproductively isolated simply by occupying different environments, which reduces chances of encountering and mating. This situation is ecological isolation (often called habitat isolation) because the two species live in distinct habitats and rarely meet, preventing gene flow before any mating occurs. It’s a prezygotic barrier since the separation happens before fertilization, due to lack of contact. The other options don’t fit: postzygotic barriers occur after mating (hybrid inviability or sterility), and mechanical isolation involves incompatible reproductive structures rather than differences in habitat.