Final answer:
Altruistic behaviors can evolve through inclusive fitness and kin selection by promoting behaviors that enhance indirect fitness with close relatives.
Step-by-step explanation:
Altruistic behaviors, which benefit other individuals at a cost to oneself, can evolve through inclusive fitness and kin selection. Inclusive fitness refers to an individual's total reproductive success, which includes both direct fitness (reproducing oneself) and indirect fitness (helping close relatives reproduce).
Kin selection occurs when individuals favor behaviors that enhance their indirect fitness with close relatives. For example, social insects like bees and ants have sterile workers that care for the queen because they are closely related to her and share genes with her offspring.
By promoting behaviors that enhance indirect fitness with close relatives, inclusive fitness and kin selection can lead to the evolution of altruistic behavior and eusociality.