The mechanics behind the beauty of roses

Science has chosen to feature a vibrant red rose on the cover of its revamped May ^1st edition. This is the first time in eleven years that the American weekly magazine has redesigned its magazine, which is now dated Thursdays instead of Fridays, to align with the publications on its website.

This red rose doesn't (only) celebrate the birth of this new model. It illustrates two studies published in the same journal this Thursday, May ^1st , explaining the geometric "trick" - which had never been observed in nature until then - that rose petals use to develop.

Using theoretical analysis, numerical simulations, and physical experiments with plasticized and rubberized sheets, the researchers established that, as the petals unfold outward, mechanical feedback regulates their growth, leading to the formation of hemmed edges and pointed corners at their tips. In botany, this is called a “cusp,” which explains the title on the cover, which could be translated as “Cusped Beauty.”

“The growth of the rose creates a kind of geometric conflict, forcing its petals into shapes where the state of bloom cannot be achieved harmoniously, without distortion, in three-dimensional space. These constraints shape the beauty of the rose and give these petals their clean, elegant edges,” the website reads.

For the authors , “this discovery redefines the understanding of how geometric constraints sculpt biological forms and opens new avenues for the engineering of shape-changing materials.”