Idea paper: Trophic transmission as a potential mechanism underlying the distribution of parasite diversity in food webs

Parasites are ubiquitous and constitute a substantial amount of natural biomass. Host species differ greatly in how many parasite species they harbor. In this idea paper, we ask what may cause the distribution of parasite diversity in an ecosystem. Since host species interact trophically in a food web and parasites are often transmitted along trophic links, we argue that trophic transmission can be a potential mechanism for explaining parasite diversity distribution. We propose a modeling framework for investigating this issue. The feasibility of our idea is demonstrated by fitting a simulation model to data derived from the Carpinteria ecosystem. Our preliminary analysis suggests that a model with trophic transmission is able to produce parasite diversity distribution similar to the empirical data better than a model without trophic transmission can. We also discuss possible extensions of our preliminary work for future research.