Out of concern that insects might destroy the murals as they move and burrow into the mural surfaces, this paper measures the adhesive forces of the Noctuid Apopestes spectrum on simulated murals in the Mogao Grottoes. In order to adhere stably to the mural surfaces, Apopestes spectrum produce a normal grip force before exerting a large tangential friction force. The maximum scratching force on the surface of the mural was about fifteen times the body weight of the insect, which might cause micro-scratches on the murals or even surface flaking.
