Fig. 2: The size of aggregates is controlled by oxygen availability.

a Domains below the meniscus at the dish border. The mosaic image was obtained by stitching confocal tile scans. h(x) is the height profile, with x the distance from the dish wall. This experiment was repeated independently once with similar results. b Influence of medium height h on the domain size in a normal atmosphere. This experiment was repeated independently three times with similar results. c Effect of a step change in the oxygen content of atmosphere while keeping h fixed. Each step lasts at least 6.6 h. This experiment was repeated independently twice with similar results. d, e Average (projected) cell density \(\bar{\rho }\) and most probable aggregate radius a as a function of equivalent height \({h}_{{{{{{{{\rm{eq}}}}}}}}}\equiv h{c}_{{{{{{{{\rm{s}}}}}}}}}/{c}_{{{{{{{{\rm{s}}}}}}}}}^{{\prime} }\) (main panels) or medium height h (insets). Colors indicate measurements from distinct samples. Circles and squares indicate oxygen partial pressure of 21% and 15%, respectively. In panel (d), error bars represent the counting error (see “Methods”) and the dotted line is the prediction of Eq. (1). In panel (e), error bars represent the width at half maximum of the size distribution \(P({a}^{{\prime} })\). Information on the numbers of aggregates considered for each point is given in Supplementary Table 1. The pink area indicates the region where a single continuous aggregate forms.