Design: Who Made Velcro?

Jens Mortensen for The New York Times

In 1941, a Swiss engineer named George de Mestral returned from a hunting trip with burs clinging to his pants and tangled in his dog's coat. When de Mestral examined the seedpods under a microscope, he marveled at how they bristled with hooks ingeniously shaped to grasp at animal fur. "Most people stop at the 'Oh, that's cool, that's what nature does,' " says Janine Benyus, a pioneer in the field of biomimicry, the science of studying natural models — anthills and lizard feet, say — to solve human problems. "He probably had to go back a lot of times," she adds, "and really look" at those hooks. A bur, of course, can clamp onto wool socks with surprising force, and — even more amazing — once you pry it off, it can stick again and again, like glue that never wears out. But how to imitate this trick with human-made stuff? Eventually de Mestral learned to mold nylon into a fabric studded with tiny hooks or loops that acted like artificial burs.

When Velcro first arrived in America, it caused a sensation. In 1958, a syndicated financial columnist named Sylvia Porter announced that "a new fastening device" had so bewitched her that she spent days playing with it. "It's on my desk as I type this," she wrote.

As for Benyus, she hopes our future will be held together with detachable hooks. Myriad plants and animals use Velcro-like attachments, she says, and engineers are now studying nature to learn how to create a "super-Velcro" that would be strong enough to fuse the pieces of a computer or maybe even a car. She points out that super-Velcro offers a lesson in sustainability. "If we were able to put the parts of a computer together with gecko tape, or insect tape, we could send the computer back to the manufacturer, and they could disassemble it and reuse different parts or recycle it easier." Benyus says. "Glue actually contaminates recyclables. We throw things in a landfill just because they're glued together. Instead, we should take our machines apart and use the building blocks again."

HOW BIRDS DO IT

Mike Hansell is a professor emeritus of animal architecture at the University of Glasgow.

Tell us about the long-tailed tits — the birds that use Velcro-like stuff to hold together their nests. Yes, one of the species in that family of birds is the American bushtit. It uses spider cocoons (or spiderweb silk) and lichen with hooklike projections to make a fabric. The bird produces a bag out of these silk loops and the plant hooks, in the manner of Velcro.

Is there some reason why the birds use the hooks and loops? Do they need to take their nests apart or "unzip" them? Well, the birds start with a nest that's small, and then they lay eggs in it. As the chicks grow, the nest needs to grow — it has to expand around the chicks. So this is an expanding fabric. I guess it's different from our human-made Velcro. This nest is much more stretchy.

So what other billion-dollar ideas could we rip off from Mother Nature? If I knew that, I'd be talking to you from my retirement villa right now.