(a)
(b)
(d)
(f )
(g)
(h)
(i)
(e)
(c)
Figure 5.1 Representative skulls of major marine mammal clades. (a) Phocidae (harbor seal, Phoca
vitulina); (b) Otariidae (Steller’s sea lion, Eumetopias jubatus); (c) Odobenidae (walrus, Odobenus rosmarus);
(d) Trichechidae (West Indian manatee, Trichechus manatus); (e) Dugongidae (dugong, Dugong dugon);
(f) Odontoceti (bottlenose dolphin, Tursiops truncatus); (g) Mustelidae (sea otter, Enhydra lutris);
(h) Ursidae (polar bear, Ursus maritimus); and (i) Mysticeti (gray whale, Eschrichtius robustus). Skull
images are not to scale.