Fig. 2.

Proximate larval responses to turbulence, tilt-inducing vorticity, and waves. Included is the percentage of larvae sinking or diving (A–C, G–I, and M–O) and the propulsive force of swimming larvae normalized by the minimum value (D–F, J–L, and P–R) vs. dissipation rate $\epsilon$ in grid-stirred tank (A–F), vs. magnitude of tilt-inducing vorticity $\xi$ in the cylinder rotating about a horizontal axis (G–L), and vs. magnitude of side-to-side acceleration $\alpha$ in shaker flask oscillating horizontally (M–R). Turbulence experiments produced large dissipation rates, strain rates, and vorticities, but accelerations were small; rotating-cylinder experiments produced large vorticities and moderate centripetal accelerations, but strain rates were negligible; shaker flask experiments produced linear wave motions with large accelerations, but vorticity and strain rate were negligible (SI Appendix, Fig. S2). Symbols are percentages or means $\pm 1$ SE of instantaneous observations within small bins ($N=100$ except $N=300$ in G, H, J, K) of $\epsilon$, $\xi$, or $\alpha$ at larval locations. Solid lines are the fitted piecewise model, and vertical lines and shaded regions indicate threshold signal $\pm 1$ SE identified by piecewise model fit (SI Appendix, Table S3). For propulsive force, the model was fitted to log₁₀$\left(\left|{\mathbf{F}}_v\right|\right)$ (SI Appendix, Figs. S3, S6, and S8); here the fitted $\left|{\mathbf{F}}_v\right|$ is normalized by minimum observed $\left|{\mathbf{F}}_v\right|$, and when converted from ${\mathrm{l}\mathrm{o}\mathrm{g}}_{10}$ to linear scale, the linear model fit is curved.