USA Biology Olympiad (USABO) Practice Exam

Which type of isolation occurs when different breeds of dogs are kept physically separate?

1. Geographical isolation

2. Behavioral isolation

3. Ecological isolation

4. Temporal isolation

The correct answer is: Ecological isolation

The correct answer, indicating that physical separation leads to different breeds of dogs being kept apart, aligns with the concept of geographical isolation. Geographical isolation occurs when physical barriers, such as mountains, rivers, or human-made structures, prevent populations from interbreeding. In the case of different breeds of dogs being kept physically separate, it is the geographical separation that impedes gene flow between these populations. Behavioral isolation refers to differences in mating behaviors or rituals that prevent different species from mating. Ecological isolation occurs when species occupy different habitats within the same area, leading to limited interaction and reproductive opportunities. Temporal isolation is related to differences in timing, such as breeding seasons. In this question, none of these other types of isolation accurately describe the scenario of physical separation among dog breeds. Therefore, geographical isolation appropriately captures the essence of how being kept apart physically results in reproductive isolation.