A new group-selection model for the evolution of homosexuality

Abstract. Scientists have long puzzled over how homosexual orientation has evolved, given the assumed low relative fitness of homosexual individuals compared to heterosexual individuals. A number of theoretical models for the evolution of homosexuality have been postulated including balance polymorphism, "Fertile females", hypervariability of DNA sequences, kin selection, and "parental manipulation". In this paper, I propose a new group-selection model for the evolution of homosexuality which offers two advantages over existing models: (1) its non-assumption of genetic determinism, and (2) its lack of dependency on an inefficient altruism relation and family dynamics theory.