Data from: Salamander ecomorphology reveals a unique suite of climbing adaptations

Many salamanders climb extensively but lack morphological adaptations,
such as claws or adhesive toe pads, found in other climbing tetrapods.
Here, we compared climbers and non-climbers from the salamander genera
Aneides and Plethodon to evaluate potential morphological adaptations for
climbing across multiple levels of biological organization. We integrated
body shape morphometrics, allometry of the autopods (manus and pes),
mechanical advantage of the digits, and comparisons of epithelial
microstructures. Compared to non-climbers, climbers have longer limbs that
likely facilitate faster climbing and have larger and positively
allometric autopods that likely yield superior clinging performance.
Longer digits increase climbing reach at the expense of grip force, but
climbers circumvent this trade-off with phalangeal morphologies that
increase the mechanical advantage of their digits. A few species also have
pes epithelia that may increase adhesion or friction but epithelial
morphology was largely uncorrelated with habitat use. While scansorial
species of Aneides and Plethodon share some characteristics with other
genera of climbing salamanders, our results reveal subtle differences
between rock-climbing and tree-climbing salamanders that reflect different
selective pressures imposed by their microhabitats. Many-to-one mapping
enables alternate strategies to address the challenges of climbing and
helps to explain the abundance and diversity of climbing tetrapods.