When Fan Xu needs a break from his mechanics of soft materials research at Fudan University, he likes to visit the campus’s lotus pool for a calming breath of fresh air. When you’re a physicist, though, sometimes a short break can backfire—in Xu’s case, leading to an 18-month study of thin biological tissue. It all started when he observed something curious in the growth of the lotus plants. “I noticed that the leaves had different shapes depending on whether they had a water foundation,” he says. “The lotus leaves floating on the water had a flat shape with wrinkles around the margin, while for leaves growing up above the water they have a global deformation, like a cone shape.” While there are a host of factors influencing the growth of a lotus leaf, including genes, Xu wondered what effect the water substrate had on leaf growth and whether he could explain the various shapes from a physics perspective. Figure 1 . The Xi Garden at Fudan University boasts a number of water lil
brought to you by the American Physical Society