The butterfly family is extremely diverse, from species sporting transparent wings to ones that look deceivingly like a dried leaf. Scientists have known for a long time that this unique insect makes use of camouflage, mimicry and other tricks to deter predators.<\/p>\n
But camouflage is often lost in flight. This new study provides the first evidence that butterflies are also masters of visual misdirection \u2013\u00a0using their flight and wing pattern, they are able to scramble a predator\u2019s sense of speed and direction.<\/p>\n
The discovery helps answer the question of why butterflies, despite sporting colours that make them stand out, which should attract predators, so often escape with their life intact, with the attacker snapping at thin air. In fact, very few predators specialise in catching butterflies mid-flight, while moths are hunted by many more visually guided aerial predators.<\/p>\n
\u201cThe stripes and spots on many butterflies\u2019 wings interfere with the way visual systems try to guess direction and speed of moving things, boosting false motion cues while hiding the butterfly\u2019s true heading,\u201d said Dr George Hancock from the University of Exeter\u2019s\u00a0Centre for Ecology and Conservation.<\/p>\n
\u201cThe illusions interfere with the predator\u2019s most basic visual targeting system and disrupt the final \u2018ballistic attack\u2019 in the tens of milliseconds when it commits to grabbing its prey, with no time to change course. As a result, birds and other predators will often simply miss.\u201d<\/p>\n The mechanism of this evasion tactic works much like the ‘barber-pole illusion’ \u2013 the red-and-white striped pole common outside barber shops, with stripes that appear to travel upward even though the pole is spinning in place.<\/p>\n \u201cButterfly wings deform as they fly \u2013 clapping together on the upstroke and peeling apart on the downstroke \u2013 so their stripes shift angle and point in different directions as they flap,\u201d said Dr Jolyon Troscianko from the University of Exeter.<\/p>\n \u201cCombined with their unpredictable flight paths, this patterning creates misleading motion illusions just like the barber-pole, causing a predator to miss entirely, or to strike a less vulnerable part of the wing, such as the hindwing or tail.\u201d<\/p>\nStudying the wings\u00a0<\/strong><\/h3>\n