Fig. 5

The temporal pattern of size, total mortality of differentiated cells, total mortality of differentiated cells, and fraction of neoblasts under growth, degrowth, and regrowth for a situation in which the planarian starts in an environment with Y _e =450 at 20 % of its steady state size. For simplicity of presentation, we scale time and divide all times in the model by 10,000 for presentation in figures. At scaled time t= 7 food is dropped to Y _e =400 and then at scaled time t=14 increased to Y _e =480. Even in the absence of a resource constraint, the cell population dynamics show a dependence upon the level of food in the environment. This is due to the feedback control on the activity of neoblasts