Meeting Abstract
Plethodontid salamanders are capable of extraordinary clinging and climbing performance. This has enabled them to access arboreal, saxicolous, troglodytic, terrestrial, and fossorial habitats to find shelter, access food, and escape predators while traversing substrates in nature that can be rough or smooth, wet or dry. Since these lungless salamanders are dependent on moist environments to ensure sufficient cutaneous respiration, the effect of water on clinging and climbing performance may constrain which habitats they have access to. We previously found that salamanders are capable of high cling performance on both smooth and roughened dry epoxy resin surfaces, depending on their body size, foot morphology, and attachment strategy. Cling performance was weakest on surfaces at a critical intermediate roughness. Salamanders cling to smooth and intermediately roughened surfaces purely through the adhesive strength of their mucus coating. Here, we examined the effect of misted and flowing water on cling performance across a range of substrate roughnesses in 12 species of plethodontid and one ambystomatid salamander. We found that water negatively impacts cling performance on smooth surfaces, but significantly improves cling performance at the critical roughness in some species. On rough substrates where salamanders could engage in gripping, water had no significant effect on cling performance. Study of cling performance and its relationship to surface roughness and wetness may cast light on how the largest family of salamanders in the world have radiated to occupy diverse habitats and inspire synthetic adhesives which function in both dry and wet conditions.
