Extended Data Fig. 2: Relationship between Prochlorococcus maximum division rates (d⁻¹) and environmental variables.

a, Data were binned by 0.25 °C intervals of seawater temperature, and the 80th percentile division rate was calculated for each bin. The lines represent a fitted generalized linear model (black) with standard error (grey shading) and generalized additive model (dotted red) (see Supplementary Table 3), illustrating the relationships between maximum division rates and seawater temperature (°C). b-d, Relationships between division rates derived from all three methods (matrix population model, dilution experiments, and cell cycle analysis) and phosphorus concentration (nmol L⁻¹) (b), light (µmol photons m⁻² s⁻¹) (c), and nitrogen concentration (nmol L⁻¹) (d). Error bars represent standard deviation of the 2000 Markov Chain Monte Carlo iterations used to infer division rates with the matrix population model, and standard deviation in estimating duration of S phase in cell cycle method. Uncertainty estimates were not reported for dilution experiments. Red and green circles highlight division rates observed at the highest temperatures that fall below (red) or above (green) the regression line in panel a.