A Study of Altruism by Genetic Algorithm

Altruism belongs to “social attributes” of individuals in a population. Model of “kinship” altruism is studied, where an altruistic individual is more likely to help its relative.In our model simulations by a modified genetic algorithm the chromosomes were defined by a presence or an absence of an altruistic disposition, affiliation to a group (kinship relation), and a fitness, initially random. No objective function is used, new fitness is created in a reproduction process from an arithmetic mean of parental fitness modified by a random number with normal distribution.Altruistic process increases fitness of a randomly chosen chromosome-recipient, and decreases fitness of a randomly chosen chromosome with an altruistic allele-donor. The increase/decrease is unproportional to an absolute value of the difference of their affiliated groups. Results suggest, that an altruistic behavior in the initial stage was created by a random genetic drift in a subgroup and initial division of a population into subgroups is crucial for its evolutionary (meta)stability.The presented simulation can be useful for evolutionary biology as well as for a modification of genetic algorithms (e.g. in artificial agents) towards natural systems.