The Cryptic impacts of invasion: functional homogenization of tropical ant communities by invasive fire ants

The diversity and distribution of traits in an ecological community shapes its responses to change and the ecosystem processes it modulates. This ‘functional diversity’, however, is not necessarily a direct outcome of taxonomic diversity. Invasions by exotic insects occur in ecosystems worldwide, but there is limited understanding of how they impact functional diversity. We present the first comprehensive trait-based investigation of the impacts of an ant invasion, and the first incorporating intraspecific polymorphisms in species-level functional diversity. The fire ant Solenopsis invicta is an invasive species with a global distribution. Focusing on invaded and uninvaded plots in tropical grasslands of Hong Kong, we investigated how the presence of S. invicta affects the diversity and distribution of ant species and traits within and across communities, the functional identities of communities, and functionally unique species. Using trait probability density functions, we built trait ...