(A–B) A representative region of axon analysis for a 24 hpf wild type (A) and klc4uw314 (B) embryo. The axons are color coded for directionality according to the legend in the upper left corner of (A). (C) Plot of axon directionality in 24 hpf wild type (green) and klc4uw314 mutants (magenta). (D) Axon directionality data was normalized to total signal and posterior angles are displayed to compare directional bias. Area under the curve was measured for shaded area and tested for statistical significance using a t-test. **P=0.0047. For (C–D), error bars = 95% CI. Wild type N=40 embryos, klc4uw314 N=23 embryos.