Genetic variability in Astyanax mexicanus using 26 microsatellite loci. Figure 3A. Proportion of shared alleles (samples of likely common ancestry determined by shared alleles) between the studied populations shown as Euclidian distances, 95% confidence ellipses represent each population. Figure 3B. Private allelic richness averaged over geographically grouped populations. Populations are coded as follows: El Abra caves (O1 - O7); Guatemala (N1 - N2); Micos (N3), Chica (O8); Surface (S1 - S4). All bar plots represent mean ± SEM. Asterisk denotes that the surface group was significantly different than each of the other groupings at the P < 0.0001, as tested by Student's t.