Maximum-likelihood estimation of the phylogenetic relationship of ancient incisor DNA sequences to extant ruminants (including orthologous sequences from the cow reference genome bosTau2). (A) Phylogenetic reconstruction using 645-bp orthologous sequence from several ruminant species. Deer sequence was used to root the trees. (B) Phylogenetic reconstruction using a 1153-bp orthologous sequence from bovine species. Sheep sequence was used to root the trees; (*) seven out of nine and 12 out of 14 substitutions on the ancient incisor branch are C > T or A > G, consistent with ancient DNA damage. The total number of substitutions is shown for each branch, along with percent support for internal nodes.
