부산대학교 도서관

We study the emergence of cell differentiation under the assumption of the existence of a given number of tradeoffs between genes encoding different functions. In the model the viability of colonies is determined by the capability of their lower level units to perform different functions, which is implicitly determined by external chemical stimuli. Due to the existence of tradeoffs it can be evolutionarily advantageous to evolve the division of labor whereby the cells can suppress their contributions to some of the activities through the activation of regulatory genes, which in its turn inflicts a cost in terms of fitness. Our simulation results show that cell differentiation is more likely as the number of tradeoffs is increased but the outcome also depends on their strength. We observe the existence of critical values for the minimum number of tradeoffs and their strength beyond that maximum cell differentiation can be attained. Remarkably, we observe the occurrence of a maximum tradeoff strength beyond that the population is no longer viable imposing an upper tolerable level of constraint at the system. This tolerance is reduced as the number of tradeoffs grows.
Comment: 6 pages, 5 figures