The neighbour-joining (NJ) tree derived from the combined data of four mtDNA fragments. Oryctolagus cuniculus was used as the outgroup. The numbers above the branches are the Bayesian posterior probabilities (PP) and the numbers below the branches are the bootstrap proportions (BS). Abbreviations of each species name are presented in the parentheses following the species name, and this abbreviation was used in the sequence names. Sequence names correspond to the sample codes listed in Additional file 4 and Additional file 2. The boxed and highlighted sequences indicated the samples with an introgressed mitochondrial genome. MtDNA of L. mandshuricus are completely replaced by mtDNA from L. timidus or L. sinensis, suggesting the absence of a "true" L. mandshuricus mtDNA lineage.
Liu et al. BMC Evolutionary Biology 2011 11:223 doi:10.1186/1471-2148-11-223