What determines parasite species richness across host species

IN FOCUS Dattilo, W., Barrozo-Chavez, N., Lira-Noriega, A., Guevara, R., Villalobos, F., Santiago-Alarcon, D., Neves, F. S., Izzo, T., & Ribeiro, S. P. (2020). Species-level drivers of mammalian ectoparasite faunas. Journal of Animal Ecology. https://doi.org/10.1111/1365-2656.13216. The question of what drives the number of parasite species able to infect a given host species is still a largely open question, despite decades of research. Dattilo and colleagues examine the potential drivers of ectoparasite species across a large set of host species to explore the taxonomic and trait drivers of host-parasite interactions. Here, we contextualize their findings, explore what is known about parasite species richness, and identify some potential next steps towards answers.