A new volcanic island forms in the Pacific Ocean. Over time, soil forms on the...
A new volcanic island forms in the Pacific Ocean. Over time, soil forms on the island, grasses grow, shrubs appear, birds nest on the island, and the island is no longer a barren rock. This is an example of which of the following?
- A. Evolution because the species on the island changed over time.
- B. A population bottleneck because the population on the island has to be very limited due to the nature of islands.
- C. A climax community because the community changed and grew more complex.
- D. Ecological succession because the structure and composition of the community has changed over time.
Correct Answer: D. Ecological succession because the structure and composition of the community has changed over time.
Explanation
This is an example of ecological succession. While climax community may seem like a reasonable answer, the text describes the entire process from barren rock onwards and does not specifically state that new species are no longer appearing on the island and that the community is stable. Evolution occurs within a species, and while the species on the island may change, the species themselves are not described as changing. This question mentions nothing about genetics, thus we cannot determine whether or not a population bottleneck (a reduction in population that is sudden and reduces genetic diversity) is occurring and we have no evidence that one is.