Investigation into the atypical locomotory apparatus of beetles and their effects on beetle movement patterns

Abstract

In this study, the claws of the beetle Mecynorhina Torquata were studied to understand how beetles can walk smoothly with only claws without struggling and slipping. The claws’ mechanism was found to result in an open-close cycle. The beetles had their claws restrained and allowed to walk on surfaces with different roughness. Opening the claws was discovered essential to a secure grip, whereas rotating the claws is needed to release it. An artificial claw was fabricated based on a natural claw and could replicate these observations. This study also investigated the role of the middle leg pair’s movement in flight cessation. Through dissections, a physical connection was found between the middle leg pair and the elytra among beetles. Subsequent experiments show that downward movement of the middle legs pull down the elytra via this connection, thereby preventing wingbeat. Front and hind leg movement caused no such effect. Finally, a free flight experiment was done to show that beetles’ altitude can be changed by manipulating its middle legs in flight.