Meeting Abstract
The gecko adhesive system has been subject to widespread investigation for many decades, but few studies explore environmentally relevant conditions that geckos likely face in their natural habitat. Recent evidence suggests that after Gekko gecko takes more than three steps on certain wet substrates, shear adhesion is significantly lower than adhesion on dry substrates, a result that is somewhat unexpected given G. gecko is native to wet tropical habitats. Interestingly, some evidence suggests that when geckos are engaged in dynamic adhesion, locomotor performance is not affected by wet substrates over a distance of 1 m. We followed up on these results by testing whether gecko locomotion would be impaired over larger distances. To answer this question, we investigated the locomotor performance of two species of geckos, G. gecko and Chondrodactylus bibronii, measured on wet glass and acrylic substrates over a distance of 2 m. We found that neither water nor substrate type had a significant effect on the average sprint velocity of either species. Furthermore, the frequency of slipping on a vertical surface, a behavior that would be expected to reduce velocity, was dependent on substrate type and species, although no significant decrease in average sprint velocity was observed. Our findings suggest that geckos are able to effectively sprint on wet surfaces up to two meters in length without a reduction in locomotor performance. These results highlight the plasticity and versatility that makes gecko adhesion such a popular biomimetic model.
