Fig. 1.

Trichodesmium N₂ fixation and growth rates for 4.5- and 7-year time points. (a) The cell-specific growth rates (blue) and N₂ fixation rates (purple) sampled at 4.5 years. The short-term (Amb-High) and long-term (High and High-Amb) responses are significantly higher than the Ambient condition. Below each sample name is the time of sampling after being transferred to the respective CO₂ environment. For example, Ambient (4.5yr) means cell lines had been growing at ambient CO₂ for 4.5 years. Amb-High means ambient cell lines were transferred to high CO₂ and sampled after 2 weeks of growth. High-Amb means high cell lines were transferred to ambient CO₂ and sampled periodically starting from 2 weeks of growth with the final time point being 2 years of growth. Bars and error bars for both plots are means and standard deviations of six biological replicates. (b) Cell-specific rates of the same cell lines and treatments shown in panel (a). Shown are the specific growth rates (blue) and N₂ fixation rates (purple) sampled at 7 years for the Ambient and High cell lines.