Robustness of Drosophila eye disc R8 cell pattern order versus stochasticity, with and without the diffusible activator Scabrous in the model.

The analysis is applied in the same setting as Fig 9, i.e. stochasticity is introduced in the diffusivity of the morphogens Du and Ds. In the absence of the diffusible activator s, there is a much increased sensitivity to stochasticity for infinitesimal non-vanishing σ. The order measure used is the fidelity of the nearest neighbor distance probability distributions.