Imagine that an alarm caller sacrifices its life to save other conspecifics. According to Hamilton's rule, how many full siblings would it have to save for the behavior to be favored?
A) at least 1.
B) at least 2.
C) at least 3.
D) Hamilton's rule cannot be satisfied.

Question

Quizplus · Accepted Answer

Hamilton's rule states that a behavior is favored if the cost to the actor is less than the benefit to the recipient multiplied by the coefficient of relatedness. For full siblings, the coefficient of relatedness is 0.5. Therefore, the benefit must be at least twice the cost, meaning at least 2 siblings need to be saved to outweigh the cost of losing one's life.

Imagine That an Alarm Caller Sacrifices Its Life to Save