Right whale
Right whales were first classified in the genus "Balaena" in 1758 by Carl Linnaeus, who at the time considered all right whales (including the bowhead) to be a single species. Through the 1800s and 1900s, in fact, the family Balaenidae has been the subject of great taxonometric debate. Authorities have repeatedly recategorised the three populations of right whale plus the bowhead whale, as one, two, three or four species, either in a single genus or in two separate genera. In the early whaling days, they were all thought to be a single species, "Balaena mysticetus".