Genomic Phylogeny of Codfish

Previous studies (Carr et al. 1999) were unable to resolve the relationships of Atlantic Cod with two endemic Pacific species, Pacific Cod (G. macrocephalus) and Alaska Pollock (Theragra chalcogramma). Work in progress by Mark Coulson strongly suggests that Theragra is more closely related to Atlantic Cod than is Pacific Cod. This implies separate, though perhaps simultaneous, invasions through the Bering Strait. Biological characteristics that have allowed Atlantic Cod and Pollock to support the world's largest marine fisheries seem to be the consequence of common ancestry, tested in separate oceans. To keep Gadus monophyletic, Theragra should again be referred to Gadus chalcogrammus Richardson, 1836 as originally described.