Fig. 3.

Mean absolute fitnesses ${\overline{w}}_a$ of the ancestor and each of 114 high-temperature adapted clones at 17 °C, 18 °C, and 19 °C. (A) The ancestor (represented as a solid black line) and 59 evolved clones persist at 18 °C and 19 °C but not at 17 °C (absolute fitnesses <0.00). (B) The subset of clones that do not persist at 18 °C but maintain a stable population at 19 °C. (C) The 15 clones with absolute fitnesses <0.00 at all three temperatures. (Insets) Inferred thermal niche for each set of clones, based on the schema defined in Fig. 1.