2.5 Biogeographical analysis
The biogeographical relationships between samples were implemented with the software PRIMER 7 (Plymouth Routines In Multivariate Ecological Research). In the Neotropical region, we pre-assigned a set of smaller hierarchical geographical areas (zones), following Morrone et al. (2022), to enable hypothesis testing using non-metric multidimensional scaling (nMDS). The faunal similarity between zones and between larger regions was quantitatively measured using Sørensen similarity index of presence/absence data, and the significance of the geographical groupings was assessed using the ANOSIM test (see Appendices S1 & S2). Species accumulation curves were implemented by the vegan package (Oksanen et al., 2017) in the software R (R Development Core Team, 2021) using 100 randomizations. Accumulation curves are randomized plots of the presence or absence of each species (here delimited by the sGMYC algorithm) against the number of observations.