According to the experiment of Diane Dodd, can adaptive divergence of allopatric fruit fly populations lead to reproductive isolation?

• A. Yes. After several generations, the reproductive barrier (behavioral isolation) between the starch- and maltose-fed populations was complete.
• B. Yes. After several generations, the reproductive barrier (mechanical isolation) between the starch- and maltose-fed populations was complete.
• C. No. After several generations, the formation of a reproductive barrier (mechanical isolation) was evident but not absolute.
• D. No. Even after several generations, there was no evidence of a reproductive barrier forming between the populations.
• E. No. After several generations, the formation of a reproductive barrier (behavioral isolation) was evident but not absolute.

Answer: (E)

Verified step by step guidance

1. Understand the concept of allopatric speciation: Allopatric speciation occurs when populations of a species become geographically isolated, leading to genetic divergence and potentially resulting in reproductive isolation.
2. Review Diane Dodd's experiment: Diane Dodd conducted an experiment with fruit flies, where populations were fed different diets (starch and maltose) to observe if adaptive divergence could lead to reproductive isolation.
3. Identify types of reproductive isolation: Reproductive isolation can be behavioral, mechanical, or other forms. Behavioral isolation involves differences in mating behaviors, while mechanical isolation involves physical incompatibilities.
4. Analyze the experiment's findings: After several generations, Dodd observed that the fruit fly populations showed evidence of behavioral isolation, but it was not complete, indicating that adaptive divergence can lead to partial reproductive isolation.
5. Conclude based on the evidence: The correct answer is that adaptive divergence led to behavioral isolation, which was evident but not absolute, demonstrating partial reproductive isolation between the starch- and maltose-fed populations.