How would you expect the behavior of a male fruit fly lacking the fru gene to differ from that of a normal male?

• A. They would not differ in their behavior because the gene encodes physical characteristics.
• B. Unlike the normal male, the male lacking the gene would not exhibit altruistic behavior and therefore would not be subject to kin selection.
• C. The male lacking the gene would look and act like a female fruit fly.
• D. The male lacking the gene will attempt to court other males rather than females.
• E. The male lacking the gene would fail to produce any offspring.

Answer: (E)

Verified step by step guidance

1. Understand the role of the fru gene in fruit flies. The fru gene is crucial for the development of male-specific behaviors, particularly those related to courtship.
2. Consider the impact of lacking the fru gene. Without this gene, a male fruit fly would not develop the typical male courtship behaviors necessary for attracting a female and successfully mating.
3. Analyze the behavioral differences. A male fruit fly lacking the fru gene may exhibit behaviors that are not aligned with typical male courtship, such as attempting to court other males or failing to court females effectively.
4. Evaluate the consequences of these behavioral changes. Due to the lack of appropriate courtship behavior, a male fruit fly without the fru gene would likely fail to mate and produce offspring.
5. Conclude that the absence of the fru gene leads to a failure in reproductive success, as the male fruit fly would not engage in successful mating behaviors necessary for offspring production.