Researchers at the University of Bristol have discovered that the tips of some saturniid moth forewings are curiously rippled and folded. They found that these unique structures strongly reflect sound, meaning that a bat hunting using echolocation is more likely to attack the wingtip region of the moth over the body, potentially saving the moth’s life.

They also discovered that the ripples and folds of the forewing tips have evolved to act as hemispheric and corner retroreflectors respectively, meaning that they reflect sound strongly back to its point of origin. Coupled together, the folds and ripples of these wingtips cover a huge range of incident sounds angles, meaning that over the entire wingbeat cycle of a flying moth and most possible positions of an attacking bat, the wingtip would consistently produce the strongest echoes. The acoustic protection of wingtips is even stronger than that of common hindwing decoys.

Read the full University of Bristol press release.