The mitochondrial genome of the sperm whale and a new molecular reference for estimating eutherian divergence dates.

摘要: Extant cetaceans are systematically divided into two suborders: Mysticeti (baleen whales) and Odontoceti (toothed whales). In this study, we have sequenced the complete mitochondrial (mt) genome of an odontocete, sperm whale (Physeter macrocephalus), included it in phylogenetic analyses together with previously mtDNAs mysticetes (the fin blue a number other mammals, including five artiodactyls hippopotamus, cow, sheep, alpaca, pig). The most strongly supported cetartiodactyl relationship was: outgroup,((pig, alpaca),((cow, sheep),(hippopotamus,(sperm whale,(baleen whales))))). As previous mtDNAs, sister-group between hippopotamus whales received strong support, making both Artiodactyla Suiformes (pigs, peccaries, hippopotamuses) paraphyletic. addition, identified Suina pig) Tylopoda alpaca), although was not supported. paleontological records odontocetes extend Oligocene, suggesting that mysticete odontocete lineages diverged 32–34 million years before present (MYBP). Use divergence date baleen allowed establishment new molecular reference, O/M-33, for dating eutherian divergences. There general consistency O/M-33 established references, A/C-60 E/R-50. Cetacean (whale) origin, i.e., cetaceans, dated to ≈55 MYBP, while basal artiodactyl divergences were ≥65 MYBP. Molecular estimates Tertiary consistent fossil record.