RESEARCH
While parasitism is the most common lifestyle on the planet, parasites are rarely considered in a larger behavioral and ecological context. However, mounting evidence suggests that parasites have substantial effects on ecosystem dynamics, from increasing food web links and connectance, to contributing substantial biomass that can exceed that of top predators. One such way that parasites can dramatically alter ecosystem dynamics is through behavioral manipulation of their hosts.
Manipulated hosts often exhibit behavioral profiles that increase parasite transmission and fitness. For example, California killifish infected with the manipulative Euhaplorchis calforniensis trematode exhibit a four-fold increase in conspicuous swimming behaviors and are 10-30 times more likely to eaten by predatory final hosts (the parasite is transmitted through predation of an infected fish by a bird) than are uninfected fish. Further, infected killifish have altered serotonin and dopamine expression, which may contribute to the observed parasite-dependent behavioral changes. These neurotransmitters influence numerous behaviors in vertebrate animals, such as foraging, locomotion, aggression, and reproduction. Our research aims to elucidate the effects of manipulative parasites on these behaviors and on predator-prey interactions. Because our study host species are abundant and ecologically important, we expect that parasite driven changes in their behavior and trophic interactions will have significant, multi-level effects on their populations, communities, and ecosystems.
Manipulated hosts often exhibit behavioral profiles that increase parasite transmission and fitness. For example, California killifish infected with the manipulative Euhaplorchis calforniensis trematode exhibit a four-fold increase in conspicuous swimming behaviors and are 10-30 times more likely to eaten by predatory final hosts (the parasite is transmitted through predation of an infected fish by a bird) than are uninfected fish. Further, infected killifish have altered serotonin and dopamine expression, which may contribute to the observed parasite-dependent behavioral changes. These neurotransmitters influence numerous behaviors in vertebrate animals, such as foraging, locomotion, aggression, and reproduction. Our research aims to elucidate the effects of manipulative parasites on these behaviors and on predator-prey interactions. Because our study host species are abundant and ecologically important, we expect that parasite driven changes in their behavior and trophic interactions will have significant, multi-level effects on their populations, communities, and ecosystems.