Final answer:
Inclusive fitness is a concept in biology that revolutionized our understanding of the evolution of social behavior. It explains why some organisms engage in altruistic behaviors that benefit the group at the expense of the individual.
Step-by-step explanation:
Inclusive fitness is a concept in biology that refers to an organism's overall reproductive success, taking into account not only its own offspring but also the offspring produced by other individuals that share some of its genes.
It was introduced by biologist W.D. Hamilton in 1964 and revolutionized our understanding of the evolution of social behavior. Inclusive fitness theory explains why some organisms, such as ants and bees, engage in altruistic behaviors that benefit the group at the expense of the individual.
For example, the worker ants in a colony are sometimes sterile and do not produce their own offspring, but they help raise the offspring of the queen. This indirectly improves their inclusive fitness by increasing the survival and reproduction of their genetically related sisters.