Wet Dry Protocells (IMAGE) Penn State Caption Membraneless compartments, called complex coacervates, which form micrometer-sized droplets (center), are widely studied as models of protocells, a potential step in the evolution of life on Earth. New research shows that the droplets behave as predicted by an experimentally derived phase diagram (left) in response to a proposed early-Earth environmental process, the wet-dry cycle as could be seen as small ponds or puddles evaporate and reform. The preference for RNA molecules (fluorescently labeled red in the right panel) to accumulate inside the droplets decreases as the solution dries. Credit Hadi Fares, Penn State Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.