Evolution of a population of protocells: emergence of species

The Gánti Chemoton represents a minimalist description of a protocell unit based on three coupled chemical networks, namely a proto'metabolism, a template duplication and the membrane growth. We here propose an improved version of Gánti's 'unit of life'where the effects of the volume changes, due to the membrane growth, are explicitly taken into account. The model is further completed by pos- tulating a stochastic mutation mechanism that acts on the template duplication. Within this framework we investigate the evolution of a population of protocells and demonstrate that our hypothesis translates into an open'ended Darwinian evolution, under the pressure of the environment. This observation enables us to conclude that the Chemoton is also a 'unit of evolution': differentiation into species is indeed an emergent property of the model.