George R. Price - Other Work in Evolutionary Theory

Other Work in Evolutionary Theory

Price developed a new interpretation of Fisher's fundamental theorem of natural selection, the Price equation, which has now been accepted as the best interpretation of a formerly enigmatic result. He wrote what is still widely held to be the best mathematical, biological and evolutionary representation of altruism. He also pioneered the application of game theory to evolutionary biology, in a co-authored 1973 paper with John Maynard Smith. Furthermore Price reasoned that in the same way as an organism may sacrifice itself and further its genes (altruism) an organism may sacrifice itself to eliminate others of the same species if it enabled closely related organisms to better propagate their related genes. This negative altruism was described in a paper published by W. D. Hamilton and is termed Hamiltonian spite.

Price’s 'mathematical' theory of altruism reasons that organisms are more likely to show altruism toward each other as they become more genetically similar to each other. As such, in a species that requires two parents to reproduce, an organism is most likely to show altruistic behavior to a biological parent, full sibling, or direct offspring. The reason for this is that each of these relatives’ genetic make up contains (on average in the case of siblings) 50% of the genes that are found in the original organism. So if the original organism dies as a result of an altruistic act it can still manage to propagate its full genetic heritage as long as two or more of these close relatives are saved. Consequently an organism is less likely to show altruistic behavior to a biological grandparent, grandchild, aunt/uncle, niece/nephew or half-sibling(each contain one-fourth of the genes found in the original organism); and even less likely to show altruism to a first cousin (contains one-eighth of the genes found in the original organism). The theory then holds that the farther genetically removed two organisms are from each other the less likely they are to show altruism to each other. If true then altruistic (kind) behavior is not truly selfless and is instead an adaptation that organisms have in order to promote their own genetic heritage.