Fig. 6. Representative fits of Eqn 2 to central O₂ concentrations in an egg mass (A) with little initial O₂ depression (Tritonia challengeriana egg mass at –1.5°C; fits shown in green) or (B) with substantial initial O₂ depression (Tritonia diomedea egg mass at 22°C; fits shown in orange). x- and y-axes are scaled differently in the two panels. When initial drawdown is slight, estimates of D from down- and up-traces are similar, whereas when initial drawdown is large they are divergent (see also Fig. 7).