(A) Comparison of morphological differences between larval surface fish and Pachón cavefish morphs. Cavefish (right) exhibit altered cranial structure compared to surface fish (left), and lack pigmentation and functional eyes. Scale bar = 0.5 mm. (B) Quantification of strike angle (left) and strike distance (right) used for behavior analysis. (C) Example time-lapse of a stereotypical surface fish strike, in lighted conditions. Surface fish move towards their prey head-on and propel themselves forward to capture. Scale bar = 1 mm. (D) Example time-lapse of a stereotypical cavefish strike, in lighted conditions. Cavefish remain immobile prior to striking nearby prey, using a lateral C-shaped motion. Scale bar = 1 mm (E) Strike angle in larval surface (N = 11) and cavefish (N = 10; Unpaired t-test, t = 9.772, df=19, P < 0.0001). (F) Strike distance in larval surface (N = 11) and cavefish (N = 10; Unpaired t-test, t = 2.884, df=19, P = 0.0095). Error bars represent + /− standard error of the mean. ** denotes P < 0.01, *** denotes P < 0.001.