Fig. 2.

Schematic phylogeny of complete mtDNAs from modern horses. This tree includes 81 sequences and was rooted by using a published donkey (E. asinus) mitochondrial genome (not displayed). AMM indicates the reconstructed AMM, whereas horse reference sequence (HRS) is the newly proposed horse reference sequence (GenBank JN398377). The topology was inferred by a maximum parsimony (MP) approach, whereas an ML time divergence scale (based on synonymous substitutions) is shown on the bottom. Additional details concerning samples, mutational motifs, and ages are given in SI Appendix, Fig. S1 and Tables S1 and S2.