daniel buenoOne of the most remarkable features of octopuses and squid is their ability to change skin color by contracting and expanding their muscles, so as to camouflage themselves in the environment. This movement changes the amount or type of pigment in skin cells called chromatophores, thereby changing the pattern of colors displayed by the animal. Scientists from the Massachusetts Institute of Technology (MIT) were able to reproduce this effect on the surface of an elastomer – a type of polymer –, using an electric field to control the voltage applied to the material. Pigments soaked into the polymer responded to changes in voltage, making pre-established patterns visible. The authors of the study, headed by mechanical engineer Xuanhe Zhao, demonstrated that the patterns produced in the experiment, including letters and shapes, could be exhibited and then erased over and over. In the future, these polymers may make it possible to replace today’s laptop, tablet, and smartphone screens with flexible displays (Nature Communications, September 16, 2014).