Figure 2. Taxa and habitats affected by agricultural intensification, urbanization, and species invasion.

(A) The competent rodent host species (Saccostomus mearnsei) of Bartonella in Kenya (image courtesy of Hillary Young). Reduced functional diversity, due to loss of large consumers and driven by agricultural expansion and intensification, increases rodent richness and abundance and thus Bartonella spillover risk. (B) The natural habitat of the flying fox (a fruit bat of the genus Pteropus) is threatened by land conversion and urbanization (reducing ecosystem phenological diversity), which in turn aggregates flying foxes at higher densities in urban areas and brings humans into closer proximity with these natural reservoirs of Hendra virus (photo by Elizabeth Shanahan). (C) Supplemental feeding of elk (Cervus canadensis) during winter months in Yellowstone National Park (image courtesy of United States Geological Survey). Agricultural conversion of land in North America has limited the availability of natural winter-feeding grounds for elk (reduced ecosystem phenological diversity). Large populations are dependent on supplemental feeding, reducing migration and promoting high density aggregations, thus increasing the risk of brucellosis spillover to livestock and humans. (D) A Burmese python (Python bivittatus) in the Everglades in Florida, USA (photo by Anne Devan-Song). This invasive species has reduced biodiversity in the Everglades (taxonomic, functional, and interaction diversity), thereby increasing the rate at which vectors feed on competent hosts of Everglade virus and thus spillover risk in this region.