“…As this science on host and parasite interactions in the above perspective grew, the perspective expanded, not just on single species parasite-host systems where the host is in essence the 'habitat' (or island, Kuris et al, 1980; but see Lawton et al, 1981) for the parasite, but an ever increasing vision of higher ecological levels of complexity from individuals to even ecosystems. With this expanding interpretation the perspective also expanded spatially, from a single host as a parasite's 'world' to metapopulations, populations, expanding from meters to kilometers and even greater spatial ranges from continents or oceans to global terrestrial, freshwater, and marine biogeographical provinces (e.g., Lafferty et al, , 2010; Morand and Krasnov, 2010;Poulin et al, 2011;Byers et al, 2014;Hopper et al, 2014;. These patterns have been exacerbated significantly by global parasite and host introductions (e.g., Thieltges et al, 2009;Sorte et al, 2010;Sousa et al, 2014).…”