"The Genetical Evolution of Social Behaviour"

"The Genetical Evolution of Social Behaviour" by W.D. Hamilton is a foundational paper that explains how social behaviors, like cooperation and altruism, can evolve through natural selection. Hamilton introduced the concept of "inclusive fitness," suggesting that individuals help relatives because they share genes, increasing the chances those genes are passed on. This idea helps explain why animals sometimes act selflessly toward kin. The paper provides a mathematical framework for understanding how such behaviors arise and persist in populations, emphasizing that the evolution of cooperation depends on genetic relatedness and the costs and benefits of social actions.