Modelling Wet-Dry Cycles in the Binary Polymer Model

A key question concerning the origin of life is whether polymers, such as nucleic acids and proteins, can spontaneously form in prebiotic conditions. Several studies have shown that, by alternating (i) a phase in which a system is in a water-rich condition and (ii) one in which there is a relatively small amount of water, it is possible to achieve polymerization. It can be argued that such “wet-dry” cycles might have actually taken place in the primordial Earth, for example in volcanic lakes. In this paper, using a version of the binary polymer model without catalysis, we have simulated wet and dry cycles to determine the effectiveness of polymerization under these conditions. By observing the behavior of some key variables (e.g., the number of different chemical species which appeared at least once and the maximum length of the species currently present in the system) it is possible to see that the alternation of wet and dry conditions can indeed allow a wider exploration of different chemical species when compared to constant conditions.