Hosts and environment overshadow spatial distance as drivers of bat fly species composition in the Neotropics

Abstract

Aim Determine the relative influence of geographical distance, environmental differences, and host species composition on the similarity of bat fly species composition. Location Neotropics. Taxon Bats (Chiroptera: Phyllostomidae) and bat flies (Diptera: Streblidae). Methods Abundance data on bats and ectoparasites were obtained from published studies. The relative influences of environmental variation (annual precipitation, temperature seasonality, elevation, and NDVI), host species composition, and geographic distance on parasite community composition were analysed with Generalized Dissimilarity Modelling and variance partitioning. Additionally, we evaluated the influence of these environmental variables and geographic distance on host species composition. Results Our model explains 45.3% of the variance in the dissimilarity of bat fly species. Host species composition had the most significant influence on bat fly species composition across communities, followed by environmental effects. Variance partitioning showed that host species composition explained 14.9% and environmental characteristics explained 10.3% of the variance in bat fly species dissimilarity. Geographical distance alone had a negligible effect as it accounted for only 0.007% of the variance in bat fly species composition. Host species composition was mainly influenced by geographic distance (18.0%) and secondarily by environmental variables (9.8%). The most important environmental variables influencing parasite and host species composition were annual precipitation and temperature seasonality, respectively. Main Conclusions The lack of relationship between geographical distance and bat fly species composition may reflect either the high mobility or the high dispersal capacity of bat flies, or a combination of these. Alternatively, it could reflect a taxonomic artefact. Environmental differences seem to directly affect bat flies, as opposed to affecting them indirectly through their impact on the hosts. Our results support the fundamental role that host species composition plays in determining the species composition of highly host‐specific parasites. However, we argue that host specificity is not the only trait impacting ectoparasite species composition.

Beta and phylogenetic diversities tell complementary stories about ecological networks biogeography

“…Interaction networks between parasites and hosts have great potential to be used as study systems in the geographic variation of interactions (Proulx et al, 2005;Poulin, 2010). Due to the particular type of association between parasites and hosts, the dissimilarity of these interactions networks reflect not only the environmental differences, but also the replacement of the host species (Krasnov et al, 2005;Poulin and Krasnov, 2010;Eriksson et al, 2019). Nevertheless, the association between parasites and hosts is often the result of the evolutionary history of the groups, and this history can result in a non-neutral contribution of these species to the beta diversity of these communities.…”

Drivers of parasite β-diversity among anuran hosts depend on scale, realm and parasite group

“…We then generated host dissimilarity matrices using the Jaccard index. Throughout this paper, spatial distance (in km) is used as a proxy for dispersal limitation [14].…”

“…Current evidence suggests that parasite turnover at broad scales is mostly affected by host diversity and climate, with a minor effect of spatial distance [10][11][12][13][14]. Since many parasites release larvae and eggs into the environment, climate has an impact on parasite survival, emergence and infectivity during these stages [15,16].…”

Multi‐site generalized dissimilarity modelling reveals drivers of species turnover in ectoparasite assemblages of small mammals across the northern and central Palaearctic

“…Moreover, a host is not merely a parasite’s food resource, but also its habitat and its dispersal vector (Poulin, 2007). It is thus not surprising that studies searching for determinants of compositional turnover in parasite assemblages have focused on both host turnover and abiotic environment, as well as often on the effect of the distance between these assemblages (Eriksson, Doherty, Fischer, Graciolli, & Poulin, 2020; Hernández‐Martínez et al, 2018; Krasnov, Mouillot, Shenbrot, Khokhlova, & Poulin, 2010; Maestri, Shenbrot, & Krasnov, 2017; van der Mescht, Khokhlova, Warburton, & Krasnov, 2017; Vinarski, Korallo, Krasnov, Shenbrot, & Poulin, 2007). However, these studies have produced contradictory results.…”