Fig. 6

Cell dynamics during remodeling following a division. We assume that the initial cell numbers are 50 % of the steady state number of neoblasts, and 10 %, 30 %, and 5 % of the steady state values of the three kinds of differentiated cells respectively (rather than 25 % neoblasts and 40 %, 30 %, 30 % relative distribution of differentiated cells in the steady state). Starting from relatively small size, the planarian grows to a steady state, since food is constant) (first panel), experiences a burst of mortality initially (second panel) as the differentiated cells apoptose in order to achieve their target values (fourth panel; colors are red: ρ ₂, black: ρ ₁, and blue: ρ ₃), and a complicated trajectory for the fraction of neoblasts as the animal readjusts its composition