Adhesive footpads have evolved many times within animals (Irschick et al. 1996; Autumn 2006; Irschick et al. 2006). We examined how adhesion scales through the prism of a broader theory about how compliance and size influence adhesion (Bartlett et al. 2012). Our approach integrates whole-animal function and evolutionary comparisons of shape. Increases in area are viewed as the most common means of increasing adhesive force as animal grow larger, but our analyses indicate that this pattern does not fully explain the increase of adhesive force with size. Our data (Figure 1) show that as geckos become larger, their adhesive system becomes stiffer. This increased stiffness allows adhesion to scale to support the weight of geckos as they become larger. Our research examines the role of the stiff tendons in the toepads of geckos, which may allow them to obtain higher stiffnesses at larger sizes.
展开▼
