TY - JOUR T1 - A mechanistic model for the evolution of multicellularity JF - bioRxiv DO - 10.1101/115832 SP - 115832 AU - André Amado AU - Carlos Batista AU - Paulo R. A. Campos Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/03/10/115832.abstract N2 - Through a mechanistic approach we investigate the formation of aggregates of variable sizes, accounting mechanisms of aggregation, dissociation, death and reproduction. In our model, cells can produce two metabolites, but the simultaneous production of both metabolites is costly in terms of fitness. Thus, the formation of larger groups can favor the aggregates to evolve to a configuration where division of labor arises. Assuming that the states of the cells in a group maximizes the per capita reproductive rate, we depict the processes affecting cells as kinetic chemical reactions by means of extensive computer simulations. In the model it is considered that the groups can grow linearly, forming a chain, or compactly keeping a roughly spherical shape. Starting from a population consisting of single-celled organisms, we observe the formation of groups with variable sizes and usually much larger than two-cell aggregates. Natural selection can favor the formation of large groups, which allows the system to achieve new and larger fitness maxima.PACS numbers ER -