Fig. 2

Cold shock produces visually distinct phenotypes within 4 h of recovery. a–c Examples of the three major phenotypic classes of living worms, with insets d–f. a, d Non-clear (NC) worms have dark pigmentation throughout the length of their intestines. b, e Immobile worms show negligible motion in response to nose-touch, and often contain apparently empty air bubbles. e Brackets indicate several of these large bubbles. c, f Clear worms show reduced pigmentation in their intestines, particularly in the posterior end. Panels g and h show the percentage of worms exhibiting each phenotype over the course of recovery from 4 h g (N = 166) and 12 h h (N = 483) cold shocks