Motor handedness bias of five Caenorhabditis species.

(A) HBVs of individual worms for N2 (n = 32), C. briggsae (n = 23), C. japonica (n = 19), C. remanei (n = 19) and C. brenneri (n = 23) samples. (B) Log (p-value of two-tailed binomial test) of the same worms as in (A) and plotted as in Fig. 4. (C) Log transformation of the p-values representing binomial logistic regression model fits for the indicated species. (D) Estimates of the binomial logistic regression π parameter for all 9 samples used in this study. There are 10 possible pairwise comparisons between the 5 N2-related strains; only one was marginally significantly different at the 0.05 threshold (spe-12 vs. gpa-16 reversed; p = 0.047). By contrast, all 5 N2-related strains are significantly different from each of the other 4 Caenorhabditis species (20 possible pairwise comparisons).