Table 3. Paired mammal species comparisons and relative rates of evolution. Branch length ratio is the ratio of the branch length for the warmer (lower latitude or elevation) species relative to that for the cooler (higher latitude or elevation). The dN/dS warmer is the ratio of the non-synonymous to synonymous substitution ratio for the low latitude or elevation species and the dN/dS cooler is the ratio of the non-synonymous to synonymous ratio for the higher latitude or elevation species. Accession numbers can be sequentially attributed to the species in a given row.