Geometrid moths are well known for their camouflage. Their wing color patterns resemble tree bark which is their preferential resting place. After landing on tree bark, many of them show the re-positioning behavior which makes the moths more cryptic effectively. Previous study revealed that moths perceive structural cues from tree bark to position their bodies. However, to date, it is not clear which sensory organ is used during re-positioning behavior. We performed a series of experiments to find out how (i.e. by using which sensory organs) moths seek out an appropriate position and body orientation. We used a geometrid moth, Jankowskia fuscaria, to test our hypothesis. We hypothesized that one of four sensory organs (eyes, antennae, front legs, and wings) may be responsible for their ability to find more cryptic position and body orientation. We amputated one of these organs and observed whether they are still able to find a cryptic position. The results indicates that visual cue is essential for their cryptic-positioning searching behavior, but antennae or front legs are not. Tactile cues from their wings seem to have a role in their behavior, but the evidence is flimsy. Therefore we cautiously conclude that moths mainly rely on visual cues (most likely through eyes) to orient their bodies on resting place, but additional tactile cues from their wings seem to play an additional role.

• Jongyeol Moon(School of Biological Sciences, Seoul National University)
• Changku Kang(School of Biological Sciences, Seoul National University)
• Piotr G. Jablonski(School of Biological Sciences, Seoul National University)