Fig. 2.

eve stripe position varies between species, not within D. melanogaster. (A and B) Anterior (A) and posterior (P) eve stripe boundaries (least-square means ± 1 SE) in stage 14a embryos in three D. melanogaster isofemale lines (Ind, Fra, and w1118) and the closely related species D. simulans and D. sechellia. Stripe boundaries were measured as distances from the anterior pole of the embryo. Means are represented as deviations by line from the mean of all of the lines, with a shift toward positive numbers indicating more posterior localization compared with the grand mean. (A) Means in absolute units (μm), uncorrected for embryo length. Stripes are located further from the anterior pole in the two large-egg strains (Ind and sechellia). (B) Relative measurement means, represented as a percentage of the embryo length. D. sechellia eve stripes remain posterior-shifted when scaled to embryo length, whereas the D. melanogaster Ind eve stripes exhibit the same scaling with length as the other two D. melanogaster lines. (C and D) Statistical significance (negative logarithm of P value) of factors influencing stripe boundary positions based on an ANOVA. Factors are age, line within D. melanogaster (mel lines), species, and the line by age interaction. The dotted line is the Bonferroni-corrected P = 0.05 cutoff. These graphs are a confluence of different ANOVAs (see Materials and Methods), as the effects of line within D. melanogaster and species were modeled separately. The species term has a significant effect on both absolute (C) and relative (D) stripe position, whereas the significance of the within D. melanogaster term (mel lines) disappears when the measurements are corrected for embryo size.