Ground-dwelling ant species adapt their body traits and food resources to specific microhabitats along an elevation gradient

Understanding the responses of species to changing climates is becoming increasingly urgent with global change impacts. Of particular importance is the impact of global environmental change on species fundamental to the functioning of ecosystems. Using elevation gradients as a proxy for climate change, we investigated the intraspecific responses of ant traits across elevations from 100-700m in a subtropical evergreen broadleaf forest. Specifically, we quantified the relationships between environmental factors, trait variation, and trophic level in two ground-dwelling ant species (Ectomomyrmex javanus, Odontoponera transversa). Morphological traits (dry mass, head length, body size and leg length) generally increased with elevation. Ant δ13C increased significantly with elevation, whereas δ15N did not. Ant δ13C values of E. javanus correlated negatively with mean annual temperature (MAT), and the δ13C values of both species correlated positively with soil C:N ratio. Our study reveals that changing temperatures along elevations are associated with changes in the individual traits and δ13C signatures of ground-dwelling ants, revealing that ants are able to adapt their body traits and food resources to specific microhabitats.