Genealogies of vkorc1 protein coding DNA sequences determined by phylogenetic analysis. Bootstrap support >90% for clades is indicated at nodes. Samples are labeled as in Additional file 1. Non-synonymous mutations identified in population samples are shown as symbols (see legend). H1-H5 denote roof rat sequences obtained in our study and verified as roof rats by DNA barcoding (Figure 2). Species designations inferred from vkorc1 sequence analysis are provided as vertical bars (right panel), but we note that species designations for other Rattus species (e.g. samples from the Azores/Terceira, Indonesia, and Thailand) are inconclusive. Note that recombination in the data should be assumed was not considered during phylogenetic analysis. For example, the separate clustering of mutations at position 139 does not imply that mutations at this position have evolved independently. Separate clusters could have originated by recombination.