Figure 1.

Comparison of the areal strain from 14 cells using the constant volume assumption, S_v, with the original data, S_o, which neglected a change in thickness. (Squares with error bars) Calculated S_v versus each measured S₀ for living (solid squares) and ghost (open squares) cells. Here, for each cell, S₀ is measured four times by using different start points for the snake algorithm under the same threshold as in Fig. 4 of Li et al. (1).