National Geographic : 2008 Apr
between the scales." A subsequent examination of the thorny devil's skin with an instrument called a micro-CT scanner confirmed his theory, revealing tiny capillaries between the scales evidently designed to guide water toward the lizard's mouth. "I think we've pretty well cracked the thorny devil structure:' he said. "We're ready to make a prototype." Enter the engineers. As the next phase in his quest to create a water-collection device inspired by the lizard, Parker sent his observations and experi mental results to Michael Rubner and his MIT colleague Robert Cohen, a chemical engineer with whom he has worked on several biomi metics projects in the past. Rubner and Cohen are neatly groomed gentlemen who speak in clipped phrases and look frequently at their watches. While Parker likes to explain his work via a stroll through a botanic garden or by pull ing out drawerfuls of bright beetles in a muse um, they are more likely to draw a tidy graph of force over time, or flip through a PowerPoint presentation on their laptop. But a pooling of biological insight and engineering prag matism is vital to success in biomimetics, and in the case of Parker, Cohen, and Rubner, it has led to several promising applications in spired by the Namib beetle and other insects. Using a robotic arm that, in a predetermined sequence, dips slides into a series of nanopar ticle suspensions and other exotic ingredients, they have assembled materials layer by layer that have the same special properties as the organisms. Soon they hope to apply the method to create a synthetic surface inspired by thorny devil skin. Though impressed by biological structures, Cohen and Rubner consider nature merely a starting point for innovation. "You don't have to reproduce a lizard skin to make a water collection device, or a moth eye to make an antireflective coating"' Cohen says. "The natural structure provides a clue to what is useful in a mechanism. But maybe you can do it better." Lessons from the thorny devil may enhance the water-collection technology they have developed based on the microstructure of the Translating whale power into wind power, biomechanist Frank Fish helped design turbine blades with tubercles (nodules) inspired by the flipper of a humpback whale (left, from a deceased animal). The flipper's scalloped edge helps it generate force in tightly banked turns. The whale-inspired blades are being tested at the Wind Energy Institute of Canada (below) to see if they can make more power at slower speeds than conventional blades, and with less noise.