C05
C05
Niche construction consequences of parasite virulence in eco-evolutionary dynamics
Jaime Anaya-Rojas & Joachim Kurtz
Parasites can have far-reaching ecological and evolutionary effects. However, parasites do not infect populations, species, or communities; they infect individuals. During infection, parasites construct their niches by altering their hosts’ physiology, morphology, and behaviour. Individuals often differ in their responses to the effects of parasites’ niche construction. Nonetheless, it remains unclear how those individual differences can alter the structure of natural communities, the energy flow of ecosystems, and even drive eco-evolutionary feedbacks? To address this question, we will integrate computational models and large-scale mesocosm experiments to test to what extent parasite effects on niche individualisation of their hosts mediate the widespread ecological and evolutionary effects of parasites. Using computational models, we will investigate under which conditions the individual-level effects of parasites alter individual trophic niche specialisation and eco-evo feedbacks. In mesocosm experiments, we will manipulate the density of three-spined sticklebacks (Gasterosteus aculeatus) and the presence/absence of two strains of the trophically transmitted tapeworm Schistocephalus solidus that vary in their virulence (and thus the strength of their niche construction effects). Using stable isotopes and stomach content data together with transcriptomic data, we will investigate the interactive effects of fish density and parasite virulence on stickleback niche individualisation. Furthermore, we will examine the ecological and evolutionary consequences of these effects by comparing the strength of trophic cascades and the selection regimes that a future fish and parasite generation will experience, thereby testing for eco-evo feedbacks driven by niche individualisation. This work will push the research boundaries in host-parasite interactions by illustrating how parasite traits drive host niche individualisation and shape eco-evolutionary dynamics.
