The acetylcholinesterase inhibitor, aldicarb, induces ventral and dorsal curling of the male tail. (a) Ventral and (b) dorsal tail curling of wild-type males in different concentrations of aldicarb (5 mM, N = 19; 2.5 mM, N = 20; 1.0 mM, N = 26; 0.5 mM, N = 21; 0.25 mM, N = 20; ddH20, N = 30). Insert figure shows the extent of tail curling (anterior is left, posterior is right, image has been flipped in (a)). (c) Comparison of ventral and (d) dorsal tail curling in wild-type control vs. unc-64 (e246) mutant males in 1 mM aldicarb and ddH20 (wild-type 1 mM aldicarb, N = 20; unc-64 (e246) 1 mM aldicarb, N = 21; wild-type ddH20, N = 20; unc-64 ddH20, N = 19). * P < 0.05, ** P < 0.005, *** P ≤ 0.0005. Error bars indicate +/- standard error of the mean.