Figure 6.

Dependence of D₀, α, β₋ and β₊ on τ in the Sorted (black), Unsorted (blue) and Aggregated (red) treatments. Error bars were computed using a bootstrap procedure described in the Statistical methods, and roughly represent 1 s.e. Dashed lines show the values used in the model presented below: D₀, β₋ and β₊ are assumed constant, and taken as the mean over all values of τ. α, however, which drives the exponential saturation of P_g (figure 4a), is fitted with the same saturation form and at the same rate ɛ as in figure 4.