The origin of interlocus sexual conflict: is sex-linkage important?

Sexual conflict has been proposed as a potential selective agent in the evolution of a variety of traits. Here, we present a simple model that investigates the initial conditions under which sex-linked and sex-limited harming alleles can invade a population. In this paper, we expand previous threshold models to study how sex-linkage and sex determination mechanisms affect the spreading conditions of a harming allele. Our models provide new insights into how sexual conflict could originate, showing that in diploid organisms the probability of a new harming allele spreading is independent of both the genetic sex determination system and the dominance relationships. However, the incidence of interlocus sexual conflicts in the initial steps of the invasion critically depends on the inheritance system.