Parasite virulence, horizontal transmission, and the evolution of host dispersal under kin interaction

Dispersal is defined as a movement causing gene flow across space. Using the direct fitness approach (Taylor & Frank 1996; Frank 1998; Rousset 2004) and the methods of convex analysis (Kuhn-Tucker's theorem), I study the evolutionary and convergence stability of host dispersal rates affected by parasitic effects such as virulence and horizontal transmission. My study reveals that (1) state-specific dispersal rates might evolve so that dispersal tendency is strongly biased towards either non-infected or infected individuals, (2) the bias is determined by parasite virulence and post-dispersal transmission/recovery rate, and (3) parasites modify host population structure by driving the evolution of host dispersal.