Home of the brave: is similarity in defensive behaviour of Neotropical snakes (Dipsadidae: Pseudoboini) predicted by sympatry?

Abstract Predation is a strong driver of prey behaviour and sympatric species are likely exposed to similar selective predatory pressures. We test the hypothesis that this leads to similar anti-predator behaviours using the widespread Neotropical snake tribe Pseudoboini as our model. We reviewed and compiled documented defensive behaviours for all species, adding new unreported behaviours for three species. We used a cluster analysis to generate a matrix of defensive behaviour dissimilarity between species. We then used a phylogenetic generalized linear mixed model to test how behaviour dissimilarity changed with geographical overlap, similarity in ecological traits, and phylogenetic relatedness. Only 41 species had available data on defensive behaviour, with only 22 of those represented in the phylogeny. We found that similarity in defensive behaviour is significantly (albeit not strongly) correlated with geographical overlap, but only for species with similar body sizes. Phylogenetic relatedness by itself was a poor predictor of behaviour dissimilarity. This corroborates our hypothesis that defensive behaviours are spatially structured at larger scales but that this can be modulated by morphological differences. Testing inter-species ecogeographical differences of defensive behaviour and its implications can be broadly applied to other taxa.