Models of food-sharing are based upon general evolutionary theory. When applied to human behavior, these models are considered a branch of human behavioral ecology. Researchers have developed several types of food-sharing models, involving phenomena such as kin selection, reciprocal altruism, tolerated theft, group cooperation, and costly signaling. Kin-selection and reciprocal-altruism models of food-sharing are based upon evolutionary concepts of kin selection and altruism. Since the theoretical basis of these models involves reproductive fitness, one underlying assumption of these models is that greater resource-accumulation increases reproductive fitness. Food-sharing has been theorized as an important development in early human evolution.[9][10][11][12]
^"The Harvey Lecture Series, 1977-1978. Food Sharing and Human Evolution: Archaeological Evidence from the Plio-Pleistocene of East Africa". Journal of Anthropological Research. 34 (3): 311–325. 1978-10-01. doi:10.1086/jar.34.3.3629782. S2CID89143790.
^McGrew, W. C.; Feistner, Anna T. C. (1995). "Chapter 4. Two Nonhuman Primate Models for the Evolution of Chimpanzees and Callitrichids". In Barkow, Jerome H.; Cosmides, Leda; Tooby, John (eds.). The Adapted Mind: Evolutionary Psychology and the Generation of Culture. Oxford University Press. p. 230. ISBN978-0-19-535647-2. Retrieved 5 February 2023. [...] Parker and Gibson (1979) suggested that food sharing arose as a secondary adaptation from tool use. [...] Sharing patterns thus created could generalize to other relationships. (Why chimpanzees [...] have not taken food sharing further in the hominid direction is not clear.)