Simulation of eyespots with various levels of organising centre activity. Signals propagate according to the t-x curves depicted on the right side of the figure. By definition, the signalling process starts at t = 0 for all four eyespots shown in this figure. However, smaller eyespots were assumed to be associated with a lower v
and shorter signal duration D. The signalling dynamics shown in Figure 6 are not shown here, but the single time point t = 10 is depicted as a snapshot. Signal durations are indicated by horizontal bars under the t axis. The front and rear of the signal for the same eyespot are depicted by arrows of the same colour. Organising centres are shown as red spots; the sizes of the spots reflect their signalling activities. Only half of an eyespot is drawn, with both the right and left sides deleted for simplicity. Note the differences in size and morphology among these four eyespots.