Mitochondrial CR-1 variation in Sardinian hares and its relationship with other Old World hares (genus Lepus)

Among the European fauna the Sardinian hare (Lepus sp.) is peculiar in that it differs from all other hares inhabiting the continent. Here, we report on the variation of a 461-bp long sequence of the hypervariable domain 1 of the mitochondrial control region (CR-1), examined in 42 hares collected throughout Sardinia and compared to the corresponding sequences of different Lepus taxa. Seventeen novel haplotypes were found in the Sardinian population, resulting in a haplotype diversity of 0.840 and a nucleotide diversity of 0.012. As a result of different analyses (Bayesian, principal coordinates) Sardinian hares grouped with North African hares, constituting a monophyletic clade that diverges from all other Old World hares, including Cape hares from South Africa and East Asia. Hence, our data agree with the figure that populations inhabiting North Africa and Sardinia form a distinct taxon, which should be possibly included into the L. capensis super-species. Moreover, two corresponding lineages can be found in Sardinia and Tunisia, providing evidence of a common origin, and thus supporting the hypothesis that North African hares were introduced into the island in historical times by sailors. Our data show that the two lineages have a geographic pattern in the wild Sardinian population, which also shows the signature of the post-introduction demographic expansion.