Have you ever tried to catch a butterfly? Now the trick that helps it escape is revealed

A study published in Nature reveals that butterfly wing patterns create motion illusions that deceive predators. High-speed photography and laboratory experiments with humans showed that stripes and patterns cause the visual system to misjudge the direction of flight, helping the butterfly escape.

A new study published in the journal Nature offers an explanation for a long-standing mystery: how colorful and conspicuous butterflies manage to evade predators while moths are more easily caught. Researchers from the Universities of Exeter and Essex in the UK filmed butterflies taking off at 1,000 frames per second. When comparing natural flight to versions where wing patterns were digitally removed, it became clear that the decorated wings generated more deceptive motion signals. The eyes perceive motion in one direction while the butterfly itself moves in another. The researchers created 3D simulations of 757 butterfly shapes from 397 European species and examined which features produced the strongest confusion effect. Notable features included vertical stripes, high contrast, and uneven patterns. In an experiment with 100 volunteers who tried to catch virtual butterflies on a touchscreen over 3,000 attempts, participants tended to miss and aim behind the butterfly. In extreme cases, the difference in attack location reached about 38% of the butterfly's average body length. An algorithm that generated 57,600 artificial wing patterns and selected those that caused the most confusion produced patterns similar to those found in nature.