Host evolutionary history rather than avian functional traits drives the Plasmodium regional assembly in the Atlantic Forest

Abstract

Disentangling the influence of hosts and environmental factors in parasite community assembly is one of the main challenges in disease ecology. Here we used three approaches to assess the influence of host ecology and evolutionary history, as well as environmental factors on Plasmodium parasite composition within the Atlantic Forest. Using sampling data of 2,241 bird individuals captured within the Brazilian Atlantic Forest, we first calculated the functional and phylogenetic host specificity of Plasmodium lineages. We then tested whether host functional or phylogenetic distance predicts Plasmodium taxonomic and phylogenetic beta diversity among host species. Finally, we tested whether temperature, precipitation, landscape dissimilarity and host turnover (taxonomic, functional and phylogenetic) determine Plasmodium taxonomic and phylogenetic turnover among 13 localities within the Atlantic Forest. We found that 47% of the parasite lineages were more phylogenetic specialists than expected by chance. In addition, both taxonomic and phylogenetic Plasmodium beta diversity were associated with host phylogenetic distance, indicating that closely related avian species are infected by assemblages composed of more closely related Plasmodium lineages. When comparing Plasmodium lineage community among localities, we found host phylogenetic turnover as the most relevant predictor of Plasmodium taxonomic and phylogenetic turnover. On the other hand, environmental variables explained 23% of Plasmodium taxonomic turnover among localities, suggesting that lineage composition is affected by climate and landscape, especially temperature seasonality. Combining all results, our findings suggest host phylogeny is the main driver of the regional Plasmodium assemblages within the Atlantic Forest. Read the free Plain Language Summary for this article on the Journal blog.