Meeting Abstract
Tropical regions of the world are known for specialist species who are uniquely adapted to intense, but relatively consistent conditions. Being near the equator, one key environmental feature is temperature. In the tropics, surface temperature of canopy branches, which are often directly exposed to the sun, can heat to > 50°C. For small cursorial canopy organisms like ants, the thermal boundary layer above these superheated substrates elevates body temperature to near critical levels. Interestingly, adhesive performance is also impacted by surface temperature. Specifically, the adhesion-mediating secretion ants produce on their soft tarsal pads should become less viscous and cause ants to slip more easily on hot surfaces. Previous work shows that adhesion is only reduced on hot substrates in some species, suggesting species-level variation in adhesive performance and mechanism as a function of surface temperature. While the tropics are known for intense and consistent heat, temperature in temperate regions can drastically vary from below -5°C to 35°C. Therefore generalist ants in the temperate zone must remain attached at a broader range of temperature than tropical arboreal ants. We investigated adhesive performance of one common temperate ant species (Camponotus pennsylvanicus) as a function of temperature, expecting that unlike specialist tropical species, this temperate generalist ant will maintain adhesive performance across the range of temperatures tested. The results of this study have important implications for understanding the ant adhesive system as well as differences in the functional morphology of specialist and generalist species.
