Swedish scientists believe they have successfully solved the mystery of the flight of butterflies. In a report published in the journal of the Royal Society Interface, Dr Per Henningsson and his colleagues analyze this subject which has baffled experts for ages.
Scientists have long wondered how some butterflies can fly with their large but inefficient wings. Now, thanks to a study led by Dr Per Henningsson of Lund University in Sweden, it is known that these extraordinary insects have developed an effective way to flap their wings to generate thrust. It turns out that this ability allows them to escape certain dangers. Butterflies therefore have their own techniques to escape predators. While some species have developed wings that are efficient enough to fly faster, others (notably moths) have a somewhat peculiar method of survival: producing a toxicity that gives them bad taste.
But what about species that are not able to fly quickly?
Slow butterflies have the peculiarity of having wings that are largely large compared to their body. These therefore prove to be less effective for theft. As the BBC reports , in the 1970s scientists had already put forward a theory that having large wings gave the insect the ability to take off faster compared to other species. Unfortunately, the publication only mentioned this hypothesis. Scientists did not take their study any further.
Today, thanks to the Swedish team led by Dr Per Henningsson, much more is known about this peculiarity of slow butterflies. To study the way the animal flies, the team used a wind tunnel and high speed cameras. “The wings behave in a pretty interesting way , ” Henningsson told the BBC. “The leading edge and the trailing edge meet in front of the central part, thus forming a pocket shape. "
“We think that this kind of behavior improves the snap because it forms an air pocket between the wings which, when they sag, makes the thrust even stronger and more efficient,” he said. added. Note that the scientists also built two mechanical wings to verify their hypothesis. One was rigid, while the other was flexible.
After their experiments, they discovered that the flexibility of the wings played an important role as it increased the force generated by the snap. As for the interest of such a study, it relates to the possibility for designers to design flying devices imitating the concept.