Appendix 1—table 4. Comparison of the angular velocity $\mathrm{\omega }$ determined from the physical skew model with experimentally measured average spindle skew rates.

The angular velocity $\mathrm{\omega }$ is calculated for each condition using Equations S21 with ${\displaystyle R=4.5\mu m}$ and $\mathrm{v}\mathrm{=}\mathrm{(}{\mathrm{v}}_{\mathrm{a}}\mathrm{+}{\mathrm{v}}_{\mathrm{p}}\mathrm{)}\mathrm{/}\mathrm{2}$ (see Appendix 1—table 3). $\mathrm{\Gamma }$ is given by Equation S23, with the hydrodynamic lengths ${\displaystyle {\ell }_L=24.8\mu m}$ and ${\displaystyle {\ell }_R=18.7\mu m}$ (Figure 5—figure supplement 3), and the measured contact surface areas on the future left and right side given by ${\mathrm{A}}_{\mathrm{L}}\mathrm{=}\mathrm{166.13}\mathrm{\pm }\mathrm{22.63}\mathsf{}\mathrm{\mu }\mathsf{}{\mathrm{m}}^{\mathrm{2}}$ and ${\mathrm{A}}_{\mathrm{R}}\mathrm{=}\mathrm{210.49}\mathrm{\pm }\mathrm{39.9}\mathsf{}\mathrm{\mu }\mathsf{}{\mathrm{m}}^{\mathrm{2}}$, respectively. Theory error: ± propagated uncertainty, Measurement error: ± 95 % confidence interval

Condition	Angular skew velocity $\omega$ [°/s] from theory	Measured average spindle skew rate [°/s]
wt	${\displaystyle -0.42\pm 0.15}$	$-0.32\pm 0.04$
ect-2	${\displaystyle -0.28\pm 0.04}$	$-0.29\pm 0.04$
rga-3	${\displaystyle -0.49\pm 0.19}$	$-0.36\pm 0.16$