Figure 1. The anthropogenic disturbance, biodiversity change, and spillover cascade.

To understand mechanisms connecting anthropogenic disturbance with spillover via biodiversity change, it is imperative to investigate how anthropogenic disturbance impacts biodiversity, and how those effects drive the perforation of the layers (intermediate processes) leading to spillover (shown using four case studies from Table 1 as examples). Zoonotic spillover arises from the alignment of multiple processes (depicted as layers). Apart from human susceptibility to infection, we found that each layer can be affected by biodiversity change, especially when considering biodiversity along multiple axes (Box 1). Connecting biodiversity change to explicit processes helps us to better understand how, when, and why biodiversity change impacts zoonotic disease risk. Numbers next to each layer correspond to the eight case studies highlighted in Table 1. All references for these case studies are included in Table 1.