Fig. 1. Emergence of proliferating and self-maintaining droplet protocells.

In the first stage, the amino acid thioester is oligomerised to produce a peptide. Droplets are formed from the product by liquid−liquid phase separation (LLPS). Continuous addition of the amino acid thioesters as a source of nutrition and physical stimulus to the droplets allows the droplets to divide while they self-reproducing autocatalytically through the incorporation of nutrients. The robustness of the proliferating droplet reflects its ability to concentrate macromolecules such as nucleic acids.