The physics of a blooming lily

Science News : Harvard physicists have described for the first time how flowers generate the forces needed to curl open come springtime, writes Daniel Strain for Science News. In their 21 March article published online in the Proceedings of the National Academy of Sciences, Haiyi Liang and L. Mahadevan studied the asiatic lily and how its petals and sepalsthe outer, greener portion of a flowergradually invert, then peel open like a banana and form a blossom. The Harvard team’s first clue to the mechanism was that the outer margins of petals and sepals ruffled during blooming, while inner surfaces stayed smooth. The researchers also developed a mathematical model to demonstrate how extra edge strain could warp thin materials like flower petals. “Infusing a scientific aesthetic into a thing of beauty only enhances our appreciation of it,” Mahadevan said. “This is what we try to do as scientists.”