One cloudless midsummer day, Andrew Parker, an evolutionary biologist, knelt in the baking red sand of an Australian desert and gently placed the right back leg of a thorny devil into a dish of water. The thorny devil, a small lizard that has learned to survive in the baking heat of the Australian desert, has a secret that fascinated Parker. "Look, look!" he exclaimed, "Its back is completely drenched!" Sure enough, in less than a minute, water from the dish had traveled up the lizard's leg, across its skin, and into its mouth. It was, in essence, drinking through its foot. The thorny devil can also do this when standing on damp sand vital competitive advantage in the desert. Parker had come here to solve the
riddle of precisely how it does this, not from purely biological interest, but with a concrete purpose in mind: to make a device to help people collect water in the desert.
From Natural Wonder to Useful Tool
Parker is a leading scientist in the field of biomimetics designs from nature to solve problems in engineering, materials science, medicine, and other fields. His studies of the body coverings of butterflies and beetles have led to brighter screens for cell phones. He sometimes draws inspiration from nature’s past: while visiting a museum in Warsaw, Poland, he noticed a 45-million-year-old fly trapped in amber and observed how the shape of its eye’s surface reduced light reflection. This shape is now being used in solar panels.
As the next phase in his plan to create a water-collection device inspired by the lizard, Parker sent his observations and experimental results to Michael Rubner and Robert Cohen, two colleagues at the Massachusetts Institute of Technology. On the one hand, Parker is full of inspiration and enthusiasm about the many possibilities of biomimetics. On the other, Rubner and Cohen are much more practical and focus on the ideas that actually have a chance of being applied successfully. This combination of biological insight and engineering pragmatism5 is vital to success in biomimetics, and has led to several promising technologies.
Though Rubner and Cohen are certainly impressed by biological structures, they consider nature merely a starting point for innovation. Cohen says, ”The natural structure provides a clue to what is useful. . . But maybe you can do it better.” Ultimately, they consider a biomimetics project a success only if it has the potential to make a useful tool for people. ”Looking at pretty structures in nature is not sufficient,” says Cohen. ”What I want to know is, can we actually transform these structures into [something] with true utility in the real world?”
Unlocking Nature’s Secrets
The work of Parker, Rubner, and Cohen is only one part of a growing global biomimetics movement. Scientists around the world are studying and trying to copy a wide variety of nature’s design secrets, with the goal of using them to create something useful. In the United States, researchers are looking at the shape of humpback whale fins in order to improve windmills that generate electric energy. The shape of the body of a certain fish has inspired designers at Mercedes-Benz to develop a more efficient car design. By analyzing how termites keep their large nests at the right temperature and humidity, architects in Zimbabwe hope to build more comfortable buildings. And in Japan, medical researchers have developed a painless needle that is similar in shape to the proboscis of a mosquito.
The Bio-Inspired Robot
Potentially, one of the most useful applications of biomimetics is the robot. Robots can perform tasks that might be too boring or dangerous for humans, but such robots are extremely difficult to build. Professor Ronald Fearing of the University of California is creating a tiny robot fly that can be used in surveillance or rescue operations. Fearing’s fly is a much simplified copy of the real thing. “Some things are just too mysterious and complicated to be able to replicate,” he says. It will still be years before his robot fly can perform anything like an actual fly, but Fearing is confident that over time he will close the gap between nature and human engineering.
At Stanford University in California, Mark Cutkosky is working on a robot gecko. As long ago as the fifth century B.C., the Greek philosopher Aristotle was amazed at how this small lizard “can run up and down a tree in any way, even with the head downward.” Cutkosky studied the extremely small structures on the gecko’s feet that allow it to run up and down vertical walls as easily as humans run down the street. He applied what he learned to create Stickybot, a robot that can walk up and down smooth vertical surfaces made, for example, of glass or plastic. The U.S. military, which funds the project, hopes that one day Stickybot will be able to climb up a building and stay there for days, monitoring the area below. Cutkosky hypothesizes a range of non-military uses as well. ”I’m trying to get robots to go places where they’ve never gone before,” he says. For now, Stickybot only climbs very clean and smooth surfaces quite slowly unlike a real gecko, which can run up just about any surface very quickly.
However, despite the promise of the field, and the brilliant people who work in it, biomimetics has led to surprisingly few business successes. Perhaps only one product has become truly famous—Velcro, which was invented in 1948 by Swiss chemist George de Mestral, who copied the way seeds called cockleburs stuck to his dog’s fur. Some blame industry, whose short-term expectations about how soon a project should be completed and become profitable conflict with the time-consuming nature of biomimetics research. But the main reason biomimetics hasn’t yet been a business success is that nature is inherently and unimaginably complex. For the present, engineers cannot hope to reproduce it.
Nonetheless, the gap with nature is gradually closing. Researchers are using more powerful microscopes, high-speed computers, and other new technologies to learn more from nature. A growing number of biomimetic materials are being produced. And although the field of biomimetics has yet to become a very successful commercial industry, it has already developed into a powerful new tool for understanding nature’s secrets.
Critical Thinking
Which feature of an animal or plant not mentioned in the reading do you think would be useful to replicate? Can you think of a practical use for it?
