Dragonflies are among nature’s most efficient hunters, capturing up to 95% of their intended prey—a far higher success rate than even birds of prey, which average around 25%.
Their four wings, which can work independently, in pairs, or together, enable extraordinary aerial agility. These insects can hover, pivot midair, and even fly backward with astonishing precision and speed.
Each wing, though ethereal in appearance, is an extension of the exoskeleton—only about three micrometers thick, just over one ten-thousandth of an inch. Despite their delicate look, these gossamer structures endure for the entirety of a dragonfly’s adult life, lasting from several weeks to a few months.
This combination of lightness and strength has long intrigued scientists seeking to understand how such fragile-seeming appendages remain so durable.
A Quest to Decode Durability
A team of researchers recently explored the wings of the African dragonfly Aethriamanta rezia, commonly called the pygmy basker, to uncover the secrets of this durability. Their findings, published in the Annals of the Entomological Society of America, offer fascinating insights into both natural design and potential industrial applications.
Co-author Dr. Kofi Adu, a physics professor at Pennsylvania State University–Altoona, typically studies nanomaterials—substances measured in billionths of a meter. When colleagues introduced him to dragonflies, he became captivated by their unique ability to shed water instantly.
“There are so many surface properties that deserve study,” Adu says, reflecting on how the insect’s wings repel water and resist damage.
Exploring the Structure of Strength
Collaborating with experts from Ghana’s University of Cape Coast, the University of Edinburgh, and the American Museum of Natural History, Adu’s team examined every facet of the dragonfly wing. Using scanning electron microscopes, they revealed an intricate landscape.
The pterostigma—the dark spot along the wing’s edge—was rough and textured. The spaces between veins contained fine, mesh-like pillars, while spines and tiny sensors called sensilla dotted the surface.
Chemical analysis uncovered 45 different cuticular hydrocarbons—waxy lipids coating the insect’s cuticle. The uneven surface enhanced these compounds’ effectiveness, creating a powerful synergy between form and chemistry.
“The nanostructures can serve as a scaffold,” Adu explains. “You increase the surface area of coverage,” allowing these tiny molecules to perform multiple protective functions.
Water-Repelling Wonders
To test how well the wings repel water, scientists placed droplets of controlled density onto the wings and measured their contact angles—the steeper the angle, the greater the hydrophobicity.
A. rezia wings recorded angles between 100.7 and 181 degrees, well within the superhydrophobic range. That means water beads up and rolls off effortlessly, rather than soaking in.
Even more astonishing, the hydrophobic quality endures over time. When researchers retested the wings three years later, they still shed water as if freshly made. “If you ask me what the shelf life is, I don’t know,” Adu admits. “But from an industrial perspective, longevity matters.”
Built-In Bacterial Defense
The same structures that repel water also discourage bacterial growth. Smooth surfaces attract bacteria, while textured ones make adhesion difficult.
On top of that, the dragonfly’s wing chemistry includes biocidal compounds that kill microbes and inert barriers that prevent them from taking hold. Together, these defenses form a natural antibacterial shield—one that could inspire self-cleaning or germ-resistant materials.
Lessons from a Natural Engineer
The team’s findings extend beyond hydrophobicity. Dragonfly wings also absorb ultraviolet light, which may serve as camouflage, and contain compounds like squalene, known for its antioxidant and anti-inflammatory properties.
Such discoveries hint at wide-ranging applications, from medical coatings to advanced materials that mimic nature’s resilience.
Adu envisions practical uses inspired by these properties—from self-cleaning surfaces to packaging that releases every drop of its contents. “Imagine a condiment packet,” he says, “that empties completely with one squeeze—nothing sticks to the walls.”
Tiny Wings, Big Insights
Reflecting on the dragonfly’s design, Adu is filled with wonder. “We know a lot—but there is so much we don’t know,” he says. “The insect wing is such a small part of the insect, yet the properties are enormous.”
Indeed, these delicate, shimmering wings may hold the key to solving modern challenges—from cleaner technologies to more efficient materials—all thanks to the quiet genius of evolution’s engineers.
FAQs
What makes dragonfly wings so durable?
Dragonfly wings are reinforced with nanostructures and coated with waxy lipids that make them strong, flexible, and resistant to water and bacteria.
How do dragonflies repel water from their wings?
Their wings are superhydrophobic, meaning water beads up and rolls off due to microscopic pillars and special chemical coatings.
What practical uses could dragonfly wing research inspire?
Scientists hope to apply these findings to create self-cleaning materials, antibacterial coatings, and packaging that doesn’t let anything stick inside.
