A Ladybug takes flight. (Photo: U. of Tokyo)
Ladybugs are beautifully colored little creatures that, like bumble bees, seem to defy nature in that they fly with bodies far larger than logic, or perceived aerodynamic rules, would enable a living entity to become airborne under its own power.
Odd as that is, scientists have long pondered another mystery about the ladybug, a type of beetle: How they manage to corral fairly substantial wings into extremely tight folds, making them – the wings – virtually invisible when the, um, bugs are at rest.
Mystery solved! Not only have Japanese scientists at the University of Tokyo figured out how that’s done, they’ve suggested that the ladybug’s wing-folding system could give rise to a change in the shape of umbrellas, the design of which had essentially remained unchanged for more than 1,000 years.
Sarah Knapston, Science Editor at The Telegraph in London, described the finding recently. In a nutshell, it boils down to the fact that the folding wing lies beneath the colorful one that shields and protects the former.
To arrive at their conclusion, the Japanese scientists replaced the spotted forewing, known as an elytron, with a transparent piece of resin. What they learned could help engineers design foldable solar collectors or even a new type of umbrella.
Kazuya Saito, Assistant Professor at the University of Tokyo’s Institute of Industrial Science, designs foldable structures—so insect wings are a natural interest. “Compared with other beetles, ladybugs are very good at flying and frequently take off,” he tells Bryson Masse at Gizmodo. “I thought their wing transformation systems are excellent and have large potential for engineering.”
He and his team tried several methods to figure out how the ladybug folded its wing. They took high-speed images of the insect opening and closing its wings, but still couldn’t see the actual folding process under the opaque spotted forewings. They attempted to 3D print an artificial wing, but they couldn’t make one that was transparent enough to see thorough.
As Masse reports, the researchers’ secretary was the one who came up with a solution: clear nail art resin. After crafting the wing out of the resin, the team was able to observe how the insect folded and unfolded its wings.
The creatures use the edge of the elytron and abdominal movements to fold the wing along creased lines. Examination of the wings using a CT scan also revealed that they have springy veins similar to a tape measure that are rigid enough to allow the insects to fly, but elastic enough to fold up.
Saito tells Masse that the wings are unusual because “transformable structures” usually involve moving parts and joints. But the ladybug’s wing lacks those complications, completing a relatively complex task through flexibility and elasticity. The paper appears in The Proceedings of the National Academies of Science.
While the structure of ladybug wings may have applications for things like foldable solar panels for satellites and space ships, Saito seems most excited about its application to something much more domestic. “I believe that beetle wing folding has the potential to change the umbrella design that has been basically unchanged for more than 1000 years,” he tells Knapton. Collapsible umbrellas usually have multiple parts and are easily broken at the joints. But the ladybug umbrella could be made from”seamless flexible frames,” he says, making it indestructible in strong wind and quick to deploy using “stored elastic energy.”
Saito admits that he doesn’t have a design for the umbrella yet, but perhaps it will look something like this.