COEVOLUTIONARY INTERACTIONS BETWEEN HOST LIFE-HISTORIES AND PARASITE LIFE-CYCLES

Several recent studies have discussed the interaction of host life-his tory traits and parasite life cycles. It has been observed that the li fe-history of a host often changes after infection by a parasite. In s ome cases, changes of host life-history traits reduce the costs of par asitism and can be interpreted as a form of resistance against the par asite. In other cases, changes of host life-history traits increase th e parasite's transmission and can be interpreted as manipulation by th e parasite. Alternatively, changes of host's life-history traits can a lso induce responses in the parasite's life cycle traits. After a brie f review of recent studies, we treat in more detail the interaction be tween the microsporidian parasite Edhazardia aedis and its host, the m osquito Aedes aegypti. We consider the interactions between the host's life-history and parasite's life cycle that help shape the evolutiona ry ecology of their relationship. In particular, these interactions de termine whether the parasite is benign and transmits vertically or is virulent and transmits horizontally.