Comparison between the setae of the dong beetle Copris ochus and the gecko Gekko gecko and the effects of deformation on their functions

摘要

Scanning electron microscopy (SEM) and histological techniques were used to observe and study the structure of setae on the integument surface of the dung beetle Copris ochus Motschulsky and on the foot pad of the gecko Gekko gecko and their relationship to anti-adherent and adherent functions respectively. There are very distinctive comparison between the structures and the constructs of the setae on the dung beetle and the gecko：the setae of the dung beetle are ramification of the integument, mainly distributing on the body abdomen surface and the lateral side of the legs, loosely arranging, having different length with many buds and sticks along the whole seta body but without side branches, uprightly directing to the contacting dung face. The setae of the gecko are protuberances from the skin, arranging in order and densely, regularly directing, branching in twice with curved top. The histological observation found that dung beetle’s setae are empty inside with lots micro-foramens communicating to the inner side on the base of the buds and sticks on the seta and also connecting with the oil glands below the integument, but without the erect muscle; Gecko setae are surrounded by fat cells and muscles. Results from functional experiments suggest that deformation of the setae of the bung beetle integument could reduce the anti-adherent function and also the same kind of change could reduce the adherent function of the gecko setae on the leg bottom. These results offer important information for preparation of the soil machine and components imitating dung beetle setae flexible non-adherence and for designing artificial setae imitating the gecko’s adherent setae [Acta Zoologica Sinica 51(4): 761–767, 2005].