HORISAWA, S.; BYRNES, G.T.; DUDLEY, R.; Univ. of California, Berkeley; Univ. of California, Berkeley; Univ. of California, Berkeley: Erratic Flight in Butterflies

Palatability of butterflies is correlated with diverse morphological features, flight speeds, and flight trajectories. In particular, palatable butterflies exhibit erratic flight paths which help in evading attack from aerial predators. We determined three-dimensional body kinematics for two species of palatable butterfly: Painted Lady butterflies (Vanessa cardui) engaged in fast and erratic flight, and Morpho butterflies (Morpho amathonte) engaged in both slow and erratic flight. Free-flight kinematic data were obtained using infrared-reflective markers and four fixed infrared-sensitive cameras at 120 frames/s (Painted Lady butterflies), and by using two fixed digital video cameras at 30 fields/s (Morpho butterflies). We derive a new parameter to describe how butterflies fly erratically, and elucidate differences in flight patterns between the two species.