Fig 9. Snapshots of the simulations for contractile activity ζΔμ = −1, surface tension γ = 2 and K = 10⁻³ at 4 different times in the simulation (corresponding to t = 25, 75, 125 and 250 respectively in simulation units).

The shading represents the Schlieren texture as used in Fig 8. The blue arrows show the flow field in the fluid (averaged over neighbouring points for clarity), while the blue line shows the droplet interface. We also use a finer mesh than that used to obtain Fig 8, with h = 0.04 and N = 150 in order to resolve the defect dynamics more clearly.