Convergent adaptation to dangerous prey proceeds through the same first‐step mutation in the garter snake Thamnophis sirtalis

“…2c) for both T. atratus (t 24.30 = 18.08, P < 0.0001) and T. sirtalis (t 8.03 = 8.62, P < 0.0001). These results are consistent with previous work showing that TTX resistance (50% MAMU) and genotype are tightly correlated in these 2 species (Feldman et al 2010;Hague et al 2017).…”

“…Moreover, a gene tree of the Na V 1.4 protein, based on genomic DNA from neonates in this study, indicates that TTX resistance in the DIV p‐loop evolved independently in the two lineages (Hague et al. ). Therefore, we assigned neonates to either the California or Pacific Northwest lineage based on the Na V 1.4 tree.…”

“…We found that newt toxin concentrations exhibited significant spatial autocorrelation (Moran's I = 0.2, p < 0.001), while snake resistance did not exhibit spatial autocorrelation (Moran's I = 0.01, p = 0.45). Maps of IDW interpolated resistance (Figure 1), and mean toxin concentrations (Figure 2) show elevated phenotypes in regions corresponding to locations of the independent evolution of different TTX‐resistance alleles (Feldman et al, 2009; Hague et al, 2017). We found that interpolated toxin concentrations significantly predicted population variation in snake resistance ( F 1,6 = 5.3, p = 0.02), and that interpolated snake resistance significantly predicted population variation in newt toxin concentrations ( F 1,45 = 11.7, p = 0.001).…”