Comparison of gene-by-gene level patterns
At a gene-by-gene level, there was no clear relationship among average F­ST and \({\overset{\overline{}}{H}}_{E}\) for orthologous genes for any species pair (Fig. 3). Average FST per gene was weakly correlated among all species pairs, with tubesnouts and ninespines having a negative albeit non-significant correlation (Table 2). A lack of similarity was also observed with \({\overset{\overline{}}{H}}_{E}\) scores, with a slightly stronger negative correlation between threespines and ninespines (Table 2). Additionally, pairwise comparisons between populations showed less similarity in \({\overset{\overline{}}{H}}_{E}\) for among-species comparisons (ρ < 0.2) than within-species comparisons (ρ > 0.4; Fig. 3B). No clear visual pattern exists in\({\overset{\overline{}}{H}}_{E}\) (Fig. 3A) or FST(Fig. 3C), with the exception of a flattening of\({\overset{\overline{}}{H}}_{E}\) and elongation of FSTtowards the ninespine axes. Overall, these patterns show broad-scale similarity between threespines and tubesnouts, which does not extend to the local gene level, or overlap with ninespines.