Protocetidae, the protocetids, form a diverse and heterogeneous group of extinct cetaceans known from Asia, Europe, Africa, South America, and North America.
Protocetidae
Drawing of Rodhocetus.
Drawing of Georgiacetus.
Cetacea is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver.
Cetacea
Skull of the North Atlantic right whale (Mysticeti)
Skull of the orca (Odontoceti)
Head profile of a beluga whale, featuring the large "melon" region