Balaenidae consists of two genera: "Eubalaena" (right whales) and "Balaena" (the bowhead whale, "B. mysticetus"). Balaenidae was thought to have consisted of only one genus until studies done through the early 2000s reported that bowhead whales and right whales are morphologically (different skull shape) and phylogenically different. According to a study done by H. C. Rosenbaum (of the American Museum of Natural History) and colleagues, the North Pacific ("E. japonica") and Southern right ("E. australis") whales are more closely related to each other than to the North Atlantic right whale ("E. glacialis").