Zebra Teaser

The pattern serves to divert the eye of birds away from the butterfly's head and body, and towards the "false antennae" tails. Immediately after settling the butterfly characteristically gyrates to face in the opposite direction and dips its head. It then slowly oscillates the hindwings, causing the tails to wiggle, which further acts to focus the observer's attention on the rear of the butterfly. - learnaboutbutterflies.com