Butterfly wing patterns may trick predators with motion illusions

On September 30, researchers discovered that the wing patterns of butterflies may deceive predators through motion illusions. When a bird attempts to catch a butterfly mid-flight, it might perceive the wings' apparent movement to be different from the actual trajectory, allowing the butterfly to escape. Professor Jolyon Troscianko from the University of Exeter and the study's leader explained that contrasting wing patterns work in tandem with wing movements to create misleading motion signals, making it challenging for predators to gauge the butterfly's speed and direction during flight.

The scientists used high-speed filming, computer modelling, simulated evolution, and touchscreen experiments to investigate this phenomenon, revealing that stripes interfere with motion detection circuits. The "barber pole illusion," where stripes moving sideways appear to move vertically, exemplifies this effect. Moreover, the patterns may increase uncertainty about the butterfly's position during an attack, making it harder for predators to overcome.

However, not all butterflies employ this strategy; brown or red-colored species seem to rely more on camouflage or warning colors. The study's findings could potentially enhance flight simulators, improve road safety, and develop protective patterns for personnel, vehicles, drones, or robots.