Fig. 6

Expression of several candidate genes associated with jaw morphological diversification in other taxa (a) or identified as affecting jaw and cranial morphology from a zebrafish mutagenesis screen (b). a Boxplots of gene expression levels for each species at all four stages of development. Gene expression values were measured as log2 transformed reads per kilobase per million reads (RPKM) for a set of candidate genes known to affect skull or cranial morphology in other wild vertebrates. These genes are not differentially expressed among different species of pupfish, with the exception of shh that tends to be slightly overexpressed in the scale-biter, and dkk3b which is underexpressed in the scale-biter. b Expression of four genes identified from a zebrafish mutagenesis screen that may contribute to jaw morphological differences among species of pupfish. Note that while edn1 is not differentially expressed, two endothelin receptors are. Letters indicate significant differential expression (FDR ≤ 0.1) in pairwise comparisons at each stage. Letters are omitted from stages where no pairwise comparisons are significant