Question

Small islands tend to have fewer species than nearby large islands. Which one or more of the following reasons explain(s) this outcome?

• A. Smaller areas have higher extinction rates.
• B. Smaller areas have low environmental heterogeneity.
• C. Smaller areas support smaller populations.
• D. Smaller areas have higher speciation rates.

Hint:

Smaller islands are more vulnerable to extinction due to limited resources, lower population sizes, and less environmental variation.

Answer 1

The Correct Option is A

Step 1: Understand island biogeography.
Island biogeography suggests that small islands typically support fewer species because they have fewer resources, lower environmental heterogeneity, and smaller populations.

Step 2: Evaluate each option.
Option (A): Correct, small islands have smaller populations and fewer resources, which increases the likelihood of extinction.
Option (B): Correct, smaller islands typically have less environmental variation, limiting the diversity of species they can support.
Option (C): Correct, smaller islands support fewer individuals, which increases the risk of extinction due to random events.
Option (D): Incorrect, smaller islands typically have lower speciation rates due to fewer ecological opportunities.
Hence, the correct answers are (A), (B), and (C).