The predicted relative change in the Dpp concentration within the domain.

(a) The relative change in the Dpp concentration at the different relative positions at four time points (light to dark grey): 24 h, 46 h, 68 h, 90 h. The coloured lines mark four different relative positions: 0.2 (blue), 0.4 (orange), 0.6 (red), 0.8 (brown). (b) The relative change in the Dpp concentration decreases over time, albeit differently at different relative positions (colours as in panel a). (EPS)