The separation of populations by barriers such as rivers, mountains, or bodies of water is called:

• A. genetic drift
• B. adaptive radiation
• C. convergent evolution
• D. geographic isolation

Answer: (D)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of geographic isolation. Geographic isolation occurs when physical barriers such as rivers, mountains, or bodies of water prevent populations of the same species from interbreeding.
2. Step 2: Recognize that geographic isolation is a mechanism of speciation, where separated populations may evolve independently due to differences in environmental pressures, genetic drift, or mutations.
3. Step 3: Compare geographic isolation with other terms provided in the problem: genetic drift, adaptive radiation, and convergent evolution. Genetic drift refers to random changes in allele frequencies, adaptive radiation involves the diversification of a species into multiple forms, and convergent evolution describes unrelated species evolving similar traits due to similar environmental pressures.
4. Step 4: Identify that none of the other terms describe the separation of populations by physical barriers. Geographic isolation is the correct term for this phenomenon.
5. Step 5: Conclude that geographic isolation is the process described in the problem, as it specifically refers to the separation of populations by physical barriers such as rivers, mountains, or bodies of water.