Natural by design

'Biomimicry' creates sustainable technology from the fruits of evolution

by Winifred Bird

I magine being able to maintain a perfect temperature and humidity in your home year round, without spending a single yen in electricity or gas bills. That’s exactly what Professor Emile Ishida of Tohoku University in northern Japan is striving to achieve — and he got the idea from termites.

After all, as any zoologist will tell you, Macrotermes michaelseni, termites that are native to parts of Africa, maintain just such a perfectly controlled environment inside their nests despite outside temperatures that can fluctuate from near freezing to 40 degrees and beyond.

Unlike most termites found in Japan and many other temperate parts of the world, M. michaelseni cannot directly digest the wood and other plant material they harvest. Instead, they build towering nests of soil where they use the chewed-up plant material to ‘farm” a type of fungus. This fungus, which the termites eat, requires a stable 30.5-degree environment in which to grow. Consequently, the termites have evolved their unique ventilation system: Air enters at the base of the nest, circulates through cool chambers underground, and finally flows out at the top of the tower, cooling the nest as it goes. The termites open and close vents throughout the day to keep the temperature even.

These natural wonders of architecture have already inspired a handful of low-energy buildings around the world. Zimbabwean architect Michael Pearce designed one such office complex, called Eastgate, in Harare in 1997. The building utilizes a complex system of vents and fans to circulate air much like a termite mound does, with a resulting reduction in heating and cooling costs of 90 percent.

But Ishida, who spent more than 20 years at tile and building-material manufacturer INAX Corp. before entering academia, had his eye on a different feature of the termite mounds: the fact that they are built of dirt. Soil is not only a good insulator, Ishida says, but its microscopic pores also condense and absorb moisture in the air. This explains the steady humidity levels in termite nests.

Of course, humans have been using soil as a building material for millenniums, but earth dwellings lack the strength demanded today (and make for a dusty house beside). Constructing earth walls like Japan’s traditional tsuchi-kabe can also be time-consuming and expensive. While baking earth into conventional bricks and ceramic tiles adds strength, the high temperature they need to be fired at destroys the nanopores vital to humidity control. So Ishida is researching a low-temperature steam treatment for tiles, called hydrothermal processing, which leaves pores intact while increasing strength.

Using these “earth ceramics” as flooring or wall-coverings virtually eliminated the need for air conditioning and heating in experimental trials, Ishida says. This April, he shared his findings with an attentive audience at the Conference for the Promotion of Manufacturing in Tokyo, whose 1,600 members include Canon, Hitachi, and Toyota. He hopes earth ceramics and other ideas inspired by nature will help Japan’s manufacturing industry wean itself from fossil fuels as global warming becomes an increasing concern.

Ishida is part of an exploding field called “biomimicry,” which looks to nature for sustainable solutions to today’s toughest design challenges. Rather than simply harvesting natural resources, biomimicry practitioners see nature as a mentor that can help us improve the way we design our world. In Japan, the field is often called “nature technology” because it draws inspiration from geological as well as biological forms.

Tiny solar batteries inspired by the way leaves turn sunlight into energy; self-cleaning tiles modeled on spotless snail shells; and improvements to Japan’s Shinkansen bullet train gleaned from the shape of kingfisher beaks and owl wings are just a few of the ideas biomimicry has spawned in recent years. The field made news again this July when the United States military revealed its study of the African freshwater fish Polypterus senegalus, whose super-protective scales may provide insight into how to create better body armor.

Seeking inspiration in nature is nothing new, of course. Thousands of years ago, the inventors of chopsticks are said to have mimicked the way a bird’s beak captures food, and in more recent centuries, Leonardo da Vinci and the Wright Brothers turned to birds once again when designing their flying machines.

However, the past several decades have seen a renewed focus on nature as a source of design ideas. As Bryony Schwan, director of the Montana, U.S.-based Biomimicry Institute puts it, biomimicry is a “revived idea.” What’s new about this latest reincarnation of biomimicry is that scientists and designers are examining nature at an increasingly microscopic level — and with a greater urgency — as the world runs through its natural resources with dizzying speed.

“Since the Industrial Revolution, we’ve owed everything to minerals and energy underground,” says Ishida. “But within 20 to 30 years, the current manufacturing system will be facing limits.”

He believes nature technology, not a lowered standard of living, is the solution.

Biomimicry was brought together as a field of study in 1997, with the publication of American biologist and writer Janine Benyus’s book, “Biomimicry: Innovation Inspired by Nature.”

In 1998, Benyus founded the Biomimicry Guild, a consulting group whose clients range from Nike to NASA, and in 2005 she started up the nonprofit Biomimicry Institute. Since her book was published, interest in both the research and business communities has mushroomed. A Web search for “biomimicry” and related terms turns up about 23.7 million hits, and between 1985 and 2005 the number of explicitly bio-inspired patents increased from just five in 1985 to 99 in 2005. Meanwhile, Benyus was last year named a Time magazine “International Hero of the Environment” — hurtling the concept of nature-as-mentor even further into the mainstream.

Japan’s biomimicry research community is one of the most active in the world, says Benyus. In 2006, she toured the country to promote the Japanese- language release of her book by Ohmsha (“Shizen to Seitai ni Manabu Biomimikuri”). She says her Japanese audiences felt a natural connection to the philosophy behind biomimicry.

“Often after the talk people would come up to me and say, ‘This resonates, for two reasons: We revere our elders and we revere nature.’ Humans are a very young organism. In biomimicry we are learning from our biological elders, from those 3.8 billion years of experience. These organisms are sensei (teachers); there is so much they can tell us.” The living creatures we see around us today, she goes on to point out, are but a tiny fraction that have managed to survive the evolutionary process.

According to Kazunori Kobayashi, a manager at the Tokyo-based nonprofit organization Japan for Sustainability (JFS), the biomimicry field started to heat up in Japan three or four years ago. In April 2004, JFS took on a one-year project to gather examples of biomimicry work. The project, funded by a ¥1.5 million grant from the Hitachi Environmental Fund, also hosted a number of lectures and workshops on the subject.

After the grant from Hitachi ended, JFS stopped its work on biomimicry — but Kobayashi was hooked. He met with Prof. Ishida, a leader in the field, and the two of them brought together a group of scientists and journalists under the banner of the Nature Technology Research Consortium. The group hosts an award-winning Web site and database of Japanese biomimicry innovations (in Japanese at www.nature-sugoi.net). Since last fall, contents from the site have also been included monthly in the Japanese environmental journal Kankyou Business.

“Nature technology can be very technical. We try to make it easy to understand even for children,” says Kobayashi, whose group aims its work mainly at junior-high through college-age students. To this end, Ishida often visits schools to introduce the concept of using nature technology to solve environmental problems like global warming.

However, although many companies are using biomimicry to develop sustainable products, bio-inspired design is not inherently tied to environmental protection.

“Some people are using biomimicry as a tool for innovation,” points out Benyus. “Others are taking the next step and doing it green.” She explains that biomimicry can happen on the level of form (the macro or micro shape of things), process (how things are made), or systems (how they interact with other things). Each has a different potential for sustainable design.

Mimicking form can make products more environmentally friendly, but that’s not always the case.

One example is a new method for creating color. Instead of using pigments, as humans have done for time immemorial, designers have figured out how to produce color the way beetles and butterflies do: by creating textured, super-thin layers of material which reflect light at various angles. In the case of the brilliant-blue Morpho butterfly, these layers are made of proteins and air. Japanese synthetic fiber company Teijin Fibers Ltd. has produced the same effect in its Morphotex fabric line using nylon and polyester instead. Similar “structural color” technology is being used in products from car paint to cosmetics, and is touted as environmentally friendly because it eliminates the need for chemical dyes and paints. However, the oil-based plastics used to produce the effect are not biodegradable.

To become truly sustainable, Benyus believes, we must mimic nature’s production processes as well as its forms. Rather than simply looking at the mechanism in a butterfly’s wing that produces color, we need to ask how the butterfly produces that mechanism. Most plant and animal material is produced at room temperature, from biodegradable materials, and without toxic byproducts. Looking more closely at the natural “factories” within butterflies, trees and other organisms may eventually provide the basis for new, more eco-friendly manufacturing methods.

And beyond mimicking forms and processes, some innovators are even thinking about how they might be able to mimic entire ecosystems.

Right now, says Benyus, humans are functioning pretty much like the weeds that take over newly plowed land: gobbling up resources as quickly as possible to produce seeds before winter comes. In nature, these greedy pioneering species are soon pushed out by longer-lasting perennial bushes and trees, and their seeds take root in a new field.

Unfortunately, though, humans have few unspoiled frontiers left to exploit. That’s why Benyus suggests it’s time for us to start acting more like a mature forest, in which nutrients are efficiently cycled so that interdependant plant communities can survive for many generations. For instance, if industrial parks could cascade byproducts from one factory to another, garbage would be reduced, resource efficiency increased, and costs potentially lowered.

Putting these ideas into practice is predictably difficult, however, and research today still outweighs product development. But the business world seems to be catching on.

“Over the past two years, nature-inspired technology has really started to take off in Japan,” says Manabu Akaike, director of research at the Tokyo-based Universal Design Intelligence environmental design firm, and host of the Science Channel’s current “Insect Technology (Shorai wo Hiraku Konchu Tekunoroji)” series on television, which showcases ideas from the insect world that have been put to work in fields from space exploration to medicine. Among the most interesting of these ideas is a potential cancer treatment inspired by silkworm moths. Professor Koichi Suzuki of Iwate University describes how the peptide yamamarin, which inhibits development of silkworm-moth eggs during winter, may also be able to stop cancer cells from growing by similarly “putting them to sleep.”

Both Akaike and Ishida have been involved in the Conference for the Promotion of Manufacturing’s efforts to embrace nature technology as a design principle. The recently formed group, which is supported by Japan’s Ministry of Economy, Trade, and Industry, drafted a “Sustainable Manufacturing Roadmap” this April that incorporates nature technology into its research goals.

Yet even as biomimicry and nature technology appear poised for greater influence, Benyus points out that species extinction is putting our natural wellspring of inspiration in jeopardy.

The International Union for the Conservation of Nature (IUCN), a network of governments, NGOs and scientists, estimates that species are going extinct at a rate between 1,000 and 10,000 times higher than the normal “background” rate. According to their data, by species one in three amphibians, one in four mammals, and one in eight birds is in danger of extinction in the near future.

To bring attention to that fact, Benyus has drawn on the IUCN’s “Red List” of endangered species in a new book project titled “Nature’s 100 Best.” The book, coauthored by longtime Japan resident Gunter Pauli, and scheduled for release in early 2009, will be a collection of 100 ideas from nature selected for their promising potential for human adaptation. Many, like the idea for a new pacemaker inspired by the way a Humpback whale’s heart beats, come from animals and plants that are in danger of extinction. The goal is to make accessing nature’s 3.8 billion years of R&D a little easier for designers and engineers worldwide.

Toward the same end, the U.S.-based Biomimicry Institute plans to put a massive peer-reviewed biomimicry database online this fall, searchable by function. Keying in the term “adhesives” into the prototype currently accessible at database.portal.modwest.com, for example, brings up detailed descriptions of 18 adhesive strategies found in nature (intermolecular attraction and suction to name just two); 13 organisms notable for their sticking power (barnacles, geckos and carnivorous plants, for instance); and a plethora of scientific papers relating to adhesives found in nature.

Here in Japan, biomimicry will get a publicity boost at a symposium on Nature Technology at the International Materials Research Society in Asia in Nagoya this December. Despite the recent frenzy of activity in the field, however, Nature Tech Consortium founding member Kobayashi admits that changing the mind-set of scientists and designers around the world is no small task.

“It may take 10 years or even a generation to make it mainstream,” he says. But he and others in the field are willing to wait.

As Prof. Ishida puts it, “This is the big wave of the future.”

Trash to cash

When trees shed their leaves they soon become food for soil organisms and break down into nutrients that the trees re-use.

However, humans’ “garbage” is rarely recycled so neatly. But one Japanese company, Taiheiyo Cement, has found a way to transform waste into a valuable resource.

Cement is commonly produced in coal-fired kilns, a resource-intensive process that contributes to global warming. But in 2004, at its factory in Hidaka-shi, Saitama Prefecture (left), Taiheiyo began trucking in municipal garbage, which is fermented and then becomes fuel for the cement kiln, which burns at high enough temperatures to safely break down dioxins in the garbage. Coal use is reduced by over 5,000 tons each year, about 90 percent of the city’s garbage is put to use — and a factory becomes a little bit more like a tree.

A better, quieter bullet train

When West Japan Railway Co. set out to develop a better Shinkansen bullet train in 1990, it encountered a problem: noise. Friction between the fast-moving train and the air around it created noise levels that exceeded Japan’s sound-pollution regulations.

Luckily, the man in charge of testing the new train, Eiji Nakatsu, happened to be a bird-watching enthusiast. One day a fellow birder told him that owls are the quietest of all birds in flight, and further research revealed that saw-like serrations on their wing feathers are responsible for this unique feature. JR etched similar serrations onto the train’s pantographs (the trapezoidal mechanism on the roof that draws electricity from overhead lines), and as a result reduced sound levels by 30 percent.

Interestingly, JR Central’s latest N700 series Shinkansen (left) also owes a lot to birds — specifically in having its front end modeled on the shape of an eagle’s outstretched wings that cut air resistance in flight.

Clean buildings take their lead from snails’ tiny bumps

Have you ever seen a dirty snail? Most likely not. That’s because, as researches at Japanese tile-manufacturer INAX Corp. discovered in the early 1990s, snail shells have special dirt-repelling properties. A pattern of tiny bumps creates microscopic pools of water on the snail’s shell. Oil-based contaminants “float” on these tiny pools, and when rain hits the shell the dirt is easily washed away.

Scientists at INAX knew a good thing when they saw it. After several years of research and testing, they developed a silica coating called Suitewall that can be painted on exterior wall tiles to protect them from exhaust, smoke and other pollutants. Silica, an element found naturally in soil, forms microscopic bumps to which moisture in the air easily adheres, creating the same kind of tiny dirt-repelling pools found on a snail’s shell. The tiles — on a house, office building or whatever — are then washed clean every time it rains. (A similar phenomenon, called the “lotus effect,” was discovered by scientists at the University of Bonn in Germany and put to use in a range of self-cleaning products.)

Farming like Mother Nature

Sometime around 10,000 years ago, humans developed agriculture, and along with it the grain and legume crops that make up the bulk of our diet. These selectively developed annual crops, harvested and replanted each year, had higher yields than their perennial ancestors, but brought with them new problems. Yearly planting requires yearly plowing, which degrades the soil structure and contributes to soil erosion.

In contrast, most natural ecosystems include perennial plants whose deep roots help create healthy soils and hold them in place year-round. Unfortunately, our current agricultural system is rapidly depleting the very soil it depends on.

That’s why researchers at the Kansas, U.S.-based Land Institute are working to develop perennial grains similar to the grasses that once covered the wild prairies. Using experimental breeding, scientists aim to combine the high yields of annual crops with the deep roots and soil-generating qualities of plants that stay in the ground year after year. By doing so, they hope to create a truly sustainable agricultural system: one that builds rather than erodes its vital soil base.

Feathery algae saves the day

Ever since the discovery of antibiotics that followed British scientist Alexander Fleming’s discovery of penicillin in 1928, doctors and scientists have been struggling to outpace bacteria’s evolving resistance to the drugs.

Antibiotics wipe out the majority of bacteria, but the strongest handful remain to reproduce into a new generation of drug-resistant diseases. The solution to this endless battle may lie in an entirely different antibacterial strategy — one that a feathery red algae named Delisea pulchra has been using for millions of years.

In 1994, Peter Steinberg, a biologist at the University of New South Wales in Sydney, Australia noticed that this particular seaweed managed to maintain a bacteria-free surface even in the unusually bacteria-rich environment of Sydney’s Botany Bay, where Steinberg was working.

Together with colleague Staffan Kjelleberg, Steinberg discovered that rather than killing bacteria, the algae block their communication signals, thus disabling the bacteria’s ability to gather on the algae’s surface. In other words, bacteria are kept at bay yet don’t have the chance to evolve newer, tougher strains.

Applications of the technology that followed from this breakthrough, now patented by Australia’s Biosignal Ltd., are expected to range from health care and sanitation to water treatment and agriculture. This year,too, an Osaka-based sanitation company (which preferred not to be named) has also begun looking into possible commercial uses for the technology.