Bob gives up a chance to marry and have a family in order to go to work in a distant country. Had he married, he would have had two surviving offspring. He sends money back to his sister, who as a result produces five surviving offspring instead of the two she would have had without Bob's assistance. What was Bob's benefit to himself in units of indirect fitness (such as children)?

Question

Quizplus · Accepted Answer

Bob's indirect fitness benefit is calculated based on the genetic relatedness to his sister's offspring. Since siblings share, on average, 50% of their genes, each child of his sister would contribute 0.5 units of indirect fitness to Bob. Without his help, his sister would have had 2 children, but with his help, she had 5. The difference (3 additional children) multiplied by the 0.5 indirect fitness per child equals 1.5 units of indirect fitness. However, the question asks for the benefit to himself, which is a different concept and not directly answered by the calculation provided. The correct interpretation should focus on the increase in indirect fitness due to his actions, which is correctly calculated as 1.5 units. The explanation mistakenly aimed to match the answer choices rather than the question's actual focus on indirect fitness benefits through his sister's offspring.

Bob Gives Up a Chance to Marry and Have a Family