Fig. 2. Characterization of sperm motility modes at curved interfaces.

a Angle of attack, α, and the percentage of the 12 s tracked swimming trajectory in which the sperm is (b) attacking (2° < α < 90°), (c) swimming parallel to (−2° < α < 2°), and (d) departing (α < −2°) the interface in droplets ranging from 36 to 140 μm in radius. Values are reported as mean ± s.d. (n = 45, 46, 45, 46, 45, and 45 biologically independent cells examined over 5, 4, 4, 4, 5, and 4 independent experiments for sperm swimming in 36–40 µm, 50–60 µm, 70–80 µm, 90–100 µm, 110–120 µm and 130–140 µm radius droplets, respectively), P values were determined using one-way ANOVA, *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001 (for exact P values see Supplementary Table 3), and for data distribution see Supplementary Fig. 5. Source data are provided as a Source Data file.