Researchers at Trinity College, Dublin (Ireland) have shown thatinsect wings are not as fragile as they appear. In a study published in the journalPLoS ONEshow that the network of veins present in the wings of insects such as grasshoppers or dragonflies help them avoid breakage. The strategy is very similar to that used when building ships, dividing the hull into compartments to prevent the ships from sinking.
According to scientists, the most emblematic example isthe desert locust ( Schistocerca gregaria ), an insect that can fly for days across deserts and oceans flapping its wings three times thinner than a human hair. During this journey, they withstand hurricane-force winds and other inclement weather without their wings suffering the slightest damage. One of its secrets resides incuticlewhich forms both the wings and the body of insects, considered the second most abundant natural material on the planet, and also one of the most resistant.
To study the resistance of these insects’ wings, the scientists made small notches in their membranes, filmed the process and measured the force required to create a fissure. At first they did not seem excessively resistant. But when they analyzed the footage in detail, they found thatmost of the cracks stopped expanding when they encountered one of the veins in the membranes, in such a way that these tiny barriers increased the strength of the wings by 50%, as explained by David Taylor, engineer and co-author of the work.
The scientists then measured the size and shape of the nearly 1,000 cells found in each wing and identified that the space separating most of the veins corresponds exactly to the so-called “critical fissure point.” Given a given stress, cracks smaller than this constant do not spread. And simultaneously the number of veins is optimal so that the wings do not weigh too much. “Thanks to this distribution of the intersecting veins,cracks always stop before they reach a critical size without losing lightness“Taylor clarifies.
