A comparative analysis of clinging ability among pad-bearing lizards

Duncan J. Irschick, Washington University in St. Louis
Christopher C. Austin, The University of Texas at Austin
Ken Petren, University of California, San Diego
Robert N. Fisher, University of California, San Diego
Jonathan B. Losos, Washington University in St. Louis
Olaf Ellers, University of California, Davis


We examined clinging ability, subdigital pad area and body mass in 14 pad-bearing lizard species from three families to test three predictions: (1) clinging ability and pad area should be tightly correlated among species; (2) pad area and clinging ability should scale similarly to body mass among 14 species; and (3) functional similarity in clinging capabilities should exist among species despite differences in body mass. One results confirm two predictions; clinging ability is tightly correlated with pad area, even when the effects of body size are removed, and the lizards examined are approximately functionally similar in their clinging capabilities. Nevertheless, despite the tight correlation between pad area and clinging ability, pad area scales with body mass by a lower slope than clinging ability. Overall, these results indicated that although pad area is a strong determinant of clinging ability, other factors enable these lizards to maintain functional similarity.