Life, as we know it, consists of replicating strings of nucleic acids. If life originated with such strings, it is reasonable to assume that they were quite short, slowly increasing in length and complexity over time. Pioneering work by Eigen and Schuster demonstrated that self-replication would have been constrained by an “error threshold”, a critical number of base-pair nucleotides above which it is unreasonable to assume a particular string could replicate itself faithfully enough to sustain an exact lineage for long times. As a consequence, more complicated replication machineries — metabolisms involving more than one string, such as primitive replicases and cooperative hypercycles — would have been necessary to avoid the error threshold. However, these metabolisms are susceptible to defection, i.e. metabolic collapse due to malfunction of one or more of the components. Two proposed mechanisms to avoid defectors are primitive cell membranes and spatial distributions which allow healthy metabolisms to evade defective elements. Membranes provide additional benefits, which can be defined by algorithmic procedures such as concentrating, splitting and merging, which make them more appealing than spatial structures. Here we show that naturally-occurring spatial structures in fluid flows can actually incorporate the benefits of both the membrane and spatialization theories, allowing for algorithmic processes to redistribute genetic material without any kind of physical membrane.
arXiv, PDF