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Green Design: Inspired by Nature
Where It All Begins
After honing its engineering skills for billions of years, nature has produced some of the world’s most innovative technologies and adaptations. From the kingfisher’s streamlined beak, designed to soften splashes, to bioluminescent marine life in the deep sea, ecosystems and animals are equipped with a wide variety of specialized machinery. Today scientists and engineers are looking to nature to tackle some of humanity’s most complex problems, a process known as biomimicry. The opportunities for innovation seem endless.

 

Hanging On

Left: Robert Clark. Right: Dee Breger/Micrographic Arts

Perhaps one of the earliest modern examples of biomimicry, Velcro was developed about 60 years ago after a walk in the woods. Swiss inventor George de Mestral, curious to understand how cockleburs attached themselves to his clothes and dog, examined the plant under a microscope and discovered a jumbled network of tiny hooks across its surface. In nature, these hooks clasp onto loose threads of fabric or animal fur for enhanced seed dispersal. But de Mestral saw potential for something else in nature’s design—a strong, yet adjustable, commercial fastener. Today Velcro can be found on a wide variety of items, from sports equipment to car interiors. Frankly, we’re not quite sure how we would have made it through kindergarten without it on our shoes.

Stick-to-itiveness

Left: Robert Clark. Right: Dennis Kunkel

Back in the fourth century B.C., Aristotle noted the gecko’s uncanny ability to crawl practically anywhere, from trees to ceilings. The lizard’s exceptional adhesive capabilities have awed scientists ever since. Nanoscale imaging of gecko feet shows millions of long, tubular filaments, known as setae, with branched tips, each of which contain 100 to 1,000 even smaller fibers. These tree- or broccoli-like structures are so small you could fit more than a thousand of them on a flat pinhead. When a gecko sets its foot down, small but powerful molecular bonds form between the surface and the millions of fibers, a phenomenon known as van de Waals forces, creating the adhesive ability that allows the lizard to cling to vertical surfaces by only one toe. Many engineering firms are racing to develop the natural sticking technology for use in a range of products, from Band-Aids and common household tapes to medical devices and robotics.

Smooth Glide

Left: Brian Skerry. Right: Robert Clark and Rebecca A. Rudolph/American Museum of Natural History

From a distance sharkskin appears fine and even, but it is actually made up of microscopic, grooved scales. The skin’s cracked texture increases its flexibility, while ridges prevent tiny eddies from forming as water flows over the surface. Both features reduce drag and allow sharks to glide smoothly and quickly through the ocean. Speedo, a swimwear manufacturer, applied sharkskin’s design to a new type of competitive body suit in 2000, and the results were undeniable. About 83 percent of medal winners at the 2000 Sydney Olympics wore the new suits, known as Fastskin. By 2007 half of the world’s swimming records had been broken by competitors wearing them.

Got You Covered

Left: Robert Clark. Right: Fabrice Bettex. Mysterra.org

Intrigued by the lotus plant’s ability to stay impeccably clean, even in the grimiest situations, scientists at Germany’s Bonn University started studying the lotus’s leaf structure in the 1990s to discover its dirt-repelling secret. While the lotus leaf may look smooth to the naked eye, microscopic imaging shows it actually has a jagged, mountainous surface texture. This rough exterior limits the contact area, and therefore the adhesive force, between the leaf and whatever lies on its surface. Water droplets slide off the plant quickly, carrying any dirt and debris with them (opposite). Mimicking nature, Sto Corp., an Atlanta-based construction materials manufacturer, applied the plant’s texture to a line of self-cleaning paints. The final product, known as Lotusan, dries quickly and resists the growth of mold, mildew, and algae. Industry researchers have also applied the lotus effect to glass and fabrics.

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Green Design: Natural Forms of Flattery
Form and function come together in nature-inspired, manmade designs.