The toothed whales (systematic name Odontoceti) form a suborder of the cetaceans. As the name suggests, the suborder is characterized by having teeth (rather than baleen as do animals in the other suborder of cetaceans, mysticeti). Toothed whales are active hunters, feeding on fish, squid, and in some cases marine mammals.

Taxonomy

• ORDER CETACEA
  • Suborder Odontoceti: toothed whales
    • Superfamily Platanistoidea: river dolphins
      • Family Iniidae
        • Genus Inia
          • Amazon River Dolphin, Inia geoffrensis
      • Family Lipotidae
        • Genus Lipotes
          • Chinese River Dolphin, Lipotes vexillifer
      • Family Platanistidae
        • Genus Platanista
          • Ganges and Indus River Dolphin, Platanista gangetica
      • Family Pontoporiidae
        • Genus Pontoporia
          • La Plata Dolphin, Pontoporia blainvillei
    • Family Monodontidae
      • Genus Monodon
        • Narwhal, Monodon monocerus
      • Genus Delphinapterus
        • Beluga, Delphinapterus leucas
    • Family Phocoenidae: Porpoises
      • Genus Neophocaena
        • Finless Porpoise, Neophocaena phocaenoides
      • Genus Phocoena
        • Harbour Porpoise, Phocoena phocaena
        • Vaquita, Phocoena sinus
        • Spectacled Porpoise, Phocoena dioptrica
        • Burmeister's Porpoise, Phocoena spinipinnis
      • Genus Phocoenoides
        • Dall's Porpoise, Phocoenoides dalli
    • Family Physeteridae: sperm whale family
      • Genus Physeter
        • Sperm Whale, Physeter macrocephalus
    • Family Kogiidae
      • Genus Kogia
        • Dwarf Sperm Whale, Kogia sima
        • Pygmy Sperm Whale, Kogia breviceps
    • Family Ziphidae, beaked whales
      • Genus Ziphius
        • Cuvier's Beaked Whale, Ziphius cavirostris
      • Genus Berardius, giant beaked whales
        • Arnoux's Beaked Whale, Berardius arnuxii
        • Baird's Beaked Whale (North Pacific Bottlenose Whale), Berardius bairdii
      • Genus Tasmacetus
        • Tasman Beaked Whale (Shepherd's Beaked Whale), Tasmacetus shepherdi
      • Subfamily Hyperoodontidae
        • Genus Indopacetus
          • Indo-Pacific Beaked Whale (Longman's Beaked Whale), Indopacetus pacificus
        • Genus Hyperoodon
          • Northern Bottlenose Whale, Hyperoodon ampullatus
          • Southern Bottlenose Whale, Hyperoodon planifrons
        • Genus Mesoplodon, mesoplodont whales
          • Hector's Beaked Whale, Mesoplodon hectori
          • True's Beaked Whale, Mesoplodon mirus
          • Gervais' Beaked Whale, Mesoplodon europaeus
          • Sowerby's Beaked Whale, Mesoplodon bidens
          • Gray's Beaked Whale, Mesoplodon grayi
          • Pygmy Beaked Whale, Mesoplodon peruvianus
          • Andrew's Beaked Whale, Mesoplodon bowdoini
          • Bahamonde's Beaked Whale, Mesoplodon bahamondi
          • Hubb's Beaked Whale, Mesoplodon carlhubbsi
          • Ginko-toothed Beaked Whale, Mesoplodon ginkgodens
          • Stejneger's Beaked Whale, Mesoplodon stejnegeri
          • Layard's Beaked Whale, Mesoplodon layardii
          • Blainville's Beaked Whale, Mesoplodon densirostris
    • Family Delphinidae: oceanic dolphins
      • Genus Cephalorhynchus
        • Commerson's Dolphin, Cephalorhyncus commersonii
        • Chilean Dolphin, Cephalorhyncus eutropia
        • Heaviside's Dolphin, Cephalorhyncus heavisidii
        • Hector's Dolphin, Cephalorhyncus hectori
      • Genus Steno
        • Rough-toothed Dolphin, Steno bredanensis
      • Genus Sousa
        • Atlantic Humpback Dolphin, Sousa teuszi
        • Indian Humpback Dolphin, Sousa plumbea
        • Pacific Humpback Dolphin, Sousa chinensis
      • Genus Sotalia
        • Tucuxi, Sotalia fluviatilis
      • Genus Tursiops
        • Bottlenose Dolphin, Tursiops truncatus
        • Indian Ocean Bottlenose Dolphin, Tursiops aduncus
      • Genus Stenella
        • Pantropical Spotted Dolphin, Stenella attenuata
        • Atlantic Spotted Dolphin, Stenella frontalis
        • Spinner Dolphin, Stenella longirostris
        • Clymene Dolphin, Stenella clymene
        • Striped Dolphin, Stenella coeruleoalba
      • Genus Delphinus
        • Short-beaked Common Dolphin, Delphinus delphis
        • Long-beaked Common Dolphin, Delphinus capensis
        • (Arabian Common Dolphin, Delphinus tropicalis)
      • Genus Lagenodelphis
        • Fraser's Dolphin, Lagenodelphis hosei
      • Genus Lagenorhynchus
        • White-beaked Dolphin, Lagenorhynchus albirostris
        • Atlantic White-sided Dolphin, Lagenorhynchus acutus
        • Pacific White-sided Dolphin, Lagenorhynchus obliquidens
        • Dusky Dolphin, Lagenorhynchus obscurus
        • Black-chinned Dolphin, Lagenorhynchus australis
        • Hourglass Dolphin, Lagenorhynchus cruciger
      • Genus Lissodelphis
        • Northern Right Whale Dolphin, Lissodelphis borealis
        • Southern Right Whale Dolphin, Lissodelphis peronii
      • Genus Grampus
        • Risso's Dolphin, Grampus griseus
      • Genus Peponocephala
        • Melon-headed Whale, Peponocephala electra
      • Genus Feresa
        • Pygmy Killer Whale, Feresa attenuata
      • Genus Pseudorca
        • False Killer Whale, Pseudorca crassidens
      • Genus Orcinus
        • Orca, Orcinus orca
      • Genus Globicephala
        • Long-finned Pilot Whale, Globicephala melas
        • Short-finned Pilot Whale, Globicephala macrorhyncus
      • Genus Orcaella
        • Irrawaddy Dolphin, Orcaella brevirostris

Anatomy

Toothed whales have a single blowhole on the top of the head (while the baleen whales possess two of them). Except for the sperm whale, most toothed whales are smaller than the baleen whales. The teeth differ considerably between the species. They may be numerous, with some dolphins bearing over 100 teeth in their jaws. The other extremum are the Narwhal with its long tusk and the almost toothless beaked whales with bizarre teeth only in males. Not all species are believed to use their teeth for feeding. For instance, the Sperm Whale is likely to use its teeth for aggression and showmanship.

Behaviour

Vocals

Vocalizations are of great importance for toothed whales. They maintain a broad variety of calls to communicate, but also are capable of using ultrasound for echolocation.

Movement

Most toothed whales swim rapidly. The smaller species occasionally ride waves, like the bow waves of ships. Most frequently can dolphins be encountered this way. They are also famous for their acrobatic breaching from the water, e.g. the Spinner Dolphin.

Social behaviour

Generally toothed whales live in groups of up to a dozen animals. These so-called schools occasionally can join, forming bigger aggregations up to thousands of whales. Toothed whales are capable of complex interactions, e.g. cooperative hunting. In captivity some species display a high potential for learning; for this reason they are considered being among the most intelligent animals.

Human Impact

The Sperm Whale has been hunted commercially for long times (see whaling). While small whales like the Pilot Whale today are still being pursued, the main threat for most species is bycatch. Especially during the tuna fishery thousands of dolphins drown each year.

Keeping small whales (mostly Bottlenose Dolphins, Orca or Belugas) in captivity is a great attraction for ocean parks and zoos. However, it is controversial because of the marine mammals' need for large spaces.