The very first life on earth is thought to have developed from 'protocells' -- liquid mixtures of many different types of molecules. Researchers have now shown that in such mixtures, small imbalances in the number of molecules of different types can have an unexpected effect. A surprising interplay with the complex pattern of interactions strongly amplifies such imbalances -- meaning that a type of molecule that is only slightly in the majority can almost entirely separate out from the others. These fundamental findings point towards a new mechanism that will apply in many complex mixtures. For instance, this would be a way for cells to control the formation of structures by fine-tuning the concentration of different molecules.
