Continental-scale shifts in termite diversity and nesting and feeding strategies

Abstract

Typically, termites are treated as a single guild, which ignores important internal diversity, including diverse feeding and nesting traits. These termite traits are crucial for both ecosystem-level fluxes and trophic webs, with implications for vertebrate species. Despite their ecological importance, the large-scale distribution of termite feeding and nesting traits and the relationship with termite diversity is largely unknown. We investigated whether functional diversity, species richness and feeding (wood, litter, grass and dung) and nesting trait (aboveground mound, belowground nest, inside tree or outside tree nest) distributions of termites were climatically controlled. To address this gap, we assembled a continental-scale database of termite traits and occurrence in Australia and modelled termite nesting and feeding traits in response to macroclimate. Functional richness and evenness increased primarily with temperature. Australia showed multiple hotspots of termite diversity with each hotspot showing a distinct guild composition. The large-scale distribution of nesting traits showed that aboveground nesting species were the most common nesting guild in the dry and wet tropics, while belowground nesting dominated in seasonally cold arid environments, demonstrating a strong climatic control on nesting strategy. Given their large biomass and many interactions with other species, the macroecology of termite traits may be especially important in predicting shifts in other species' distributions at continental and global scales.