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By Ian Sample Picking up a design tip from the penguins. IN AN old Army hospital on the campus of Reading University, Colin Dawson is being taught by penguins. What he hopes to learn is how, exactly, they manage to survive on the coldest continent in the world -Antarctica. But his work with Dr Julian Vincent, a director of the university's Centre for Biomimetics, isn't driven by mere scientific curiosity. Understanding the penguin's secret could help scientists design better clothing for humans working in some of the most formidable environments on Earth. Indeed, their research is being backed by the Defence Clothing and Textile Agency, part of the Ministry of Defence. As Dawson explains: ''If you're trying to design something to perform extremely well, it seems sensible to look at something which is able to do it anyway.'' The whole notion of looking to Nature for answers is steadily becoming a science in itself. Because what Nature lacks in intelligence, she more than compensates for in experience. Over hundreds of mil lions of years, Nature has used simple trial and error to tackle problems similar to those that scientists and engineers wrestle with every day. And the results are everywhere; the bones in a bird's wing are strong but incredibly light, while spider silk is as strong as a steel, but incredibly elastic and completely recyclable. The reason for Nature's success is clear; she doesn't suffer bad design. ''In Nature,'' says Dr Vincent, ''the good designs eat the bad, it's as simple as that.'' Even so, it's hard to imagine how Nature, using ''the dumb mechanism of natural selection'', as Dawson puts it, can outsmart our finest scientists and engineers. The answer, it seems, lies in the fact that man has concentrated on using high temperatures, high pressures and aggressive chemicals to make an everincreasing variety of materials. In Nature's workshops almost everything must be made at ambient temperature and pressure, and the most common solvent is water. The result, says Dr Vincent, is simple: ''Whereas engineers have majored on material, Nature has majored on design.'' So restricted in her choice of materials, Nature was forced to invest in structure. And because biological structures can be built up from the tiniest blocks - molecule by molecule - the designs found in Nature are often far more complex than anything we can produce today. AS A TESTING ground for biological design, there can be few places as harsh as Antarctica. Dr Tony Williams of Simon Fraser University in British Columbia spent three years studying penguins on Bird Island, the British Antarctic Survey base in South Georgia. ''In Antarctica,'' he says, ''the temperature goes down to about - 40C, but there are also very strong winds, so the wind chill can be extreme.'' Despite these bitter conditions, Emperor penguins flock to Antarctica every year to breed. Their brief courtship produces a single egg, which is left with the male to incubate. Balancing the egg on his feet, the male will huddle with other penguins for up to four months. None of them will eat during this period and when the egg is ready to hatch, the parents will have lost almost half of their body weight. To help them endure such adverse conditions, Emperor penguins have developed highly efficient insulation. But they don't have a huge fatty layer. ''About 80 per cent of the insulation comes from the feathers,'' says Williams. And while more birds' feathers grow along a few welldefined tracks, penguins grow feathers all over, so no part of their skin is exposed. On land, penguins use tiny muscles to erect their feathers, forming a barrier zone of still air around their bodies. This is their first line of defence against the cold. The second line of defence is the downy layers at the root of each feather. This traps air very close to the skin, in extremely small, regularsized pockets. The size of these air pockets is critical for good insulation and through natural selection, Nature appears to have produce the optimum structure. Each fibre of down has along its length, a number of spikes, or nodes. When fibres from neighbouring plumes push into each other, these nodes make the fibres buckle into regular sized loops, producing a dense structure of tiny air pockets and by trapping the air as efficiently as this, the penguin reduces i ts heat l oss drastically. But despite the penguin's success, we are unlikely to end up waddling around in feather suits next winter. As Daedalus and Icarus proved, it can be foolish to copy Nature slavishly. ''We only need the essential features,'' emphasises Dawson. ''There are some good ideas in there and my job is to go in and steal them.'' And until he does, we can keep warm using another of the penguin's tricks - we can all just huddle together. |