Suborder Odontoceti, toothed whales
Family Delphinidae, oceanic dolphins
Genus Delphinus
Long-Beaked Common Dolphin, Delphinus capensis
Short-Beaked Common Dolphin, Delphinus delphis
Genus Tursiops
Common Bottlenose Dolphin, Tursiops truncatus
Indo-Pacific Bottlenose Dolphin, Tursiops aduncus
Genus Lissodelphis
Northern Rightwhale Dolphin, Lissodelphis borealis
Southern Rightwhale Dolphin, Lissodelphis peronii
Genus Sotalia
Tucuxi, Sotalia fluviatilis
Costero, Sotalia guianensis
Genus Sousa
Indo-Pacific Hump-backed Dolphin, Sousa chinensis
Chinese White Dolphin (the Chinese variant), Sousa chinensis chinensis
Atlantic Humpbacked Dolphin, Sousa teuszii
Genus Stenella
Atlantic Spotted Dolphin, Stenella frontalis
Clymene Dolphin, Stenella clymene
Pantropical Spotted Dolphin, Stenella attenuata
Spinner Dolphin, Stenella longirostris
Striped Dolphin, Stenella coeruleoalba
Genus Steno
Rough-Toothed Dolphin, Steno bredanensis
Genus Cephalorhynchus
Chilean Dolphin, Cephalorhynchus eutropia
Commerson's Dolphin, Cephalorhynchus commersonii
Heaviside's Dolphin, Cephalorhynchus heavisidii
Hector's Dolphin, Cephalorhynchus hectori
Genus Grampus
Risso's Dolphin, Grampus griseus
Genus Lagenodelphis
Fraser's Dolphin, Lagenodelphis hosei
Genus Lagenorhynchus
Atlantic White-Sided Dolphin, Lagenorhynchus acutus
Dusky Dolphin, Lagenorhynchus obscurus
Hourglass Dolphin, Lagenorhynchus cruciger
Pacific White-Sided Dolphin, Lagenorhynchus obliquidens
Peale's Dolphin, Lagenorhynchus australis
White-Beaked Dolphin, Lagenorhynchus albirostris
Genus Orcaella
Australian Snubfin Dolphin, Orcaella heinsohni
Irrawaddy Dolphin, Orcaella brevirostris
Genus Peponocephala
Melon-headed Whale, Peponocephala electra
Genus Orcinus
Killer Whale (Orca), Orcinus orca
Genus Feresa
Pygmy Killer Whale, Feresa attenuata
Genus Pseudorca
False Killer Whale, Pseudorca crassidens
Genus Globicephala
Long-finned Pilot Whale, Globicephala melas
Short-finned Pilot Whale, Globicephala macrorhynchus
Genus Australodelphis
Australodelphis mirus
Family Platanistidae
Ganges and Indus River Dolphin, Platanista gangetica with two subspecies
Ganges River Dolphin (or Susu), Platanista gangetica gangetica
Indus River Dolphin (or Bhulan), Platanista gangetica minor
Family Iniidae
Amazon River Dolphin (or Boto), Inia geoffrensis
Family Lipotidae
Baiji (or Chinese River Dolphin), Lipotes vexillifer (possibly extinct, since December 2006)
Family Pontoporiidae
La Plata Dolphin (or Franciscana), Pontoporia blainvillei
Six species in the family Delphinidae are commonly called "whales" but genetically are dolphins. They are sometimes called blackfish.
Melon-headed Whale, Peponocephala electra
Killer Whale (Orca), Orcinus orca
Wolphin Kawili'Kai at the Sea Life Park in Hawaii.
Pygmy Killer Whale, Feresa attenuata
Wolphin Kawili'Kai at the Sea Life Park in Hawaii.
False Killer Whale, Pseudorca crassidens
Long-finned Pilot Whale, Globicephala melas
Short-finned Pilot Whale, Globicephala macrorhynchus
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacean order, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are among the most intelligent animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture
Amazing Facts about Dolphin
- Like bats, dolphins use echolocation for movement and locating objects.
- Can hear frequencies up to at least 100,000 Hz.
- dolphins are mammals? They give birth to live young and nurse them with milk.
- dolphins have to come up to the surface to breathe? Most dolphins surface every few minutes, but they can stay under water for up to 15 minutes. A dolphin breathes through the blowhole on top of its head.
- dolphins evolved from land animals? The land ancestor of the dolphin lived about 50 million years ago and looked a little like a wolf. This animal hunted in shallow waters and by and by adapted itself to life in water: the forelegs became flippers, the hindlegs disappeared and the fluke evolved, the fur disappeared and the nostrils moved to the top of the head.
- dolphins use echolocation to navigate and to find food? Dolphins send out clicks that are returned from other objects in the water (just like an echo). This way a dolphin can locate food, other dolphins, predators or rocks.
- dolphins live in families? These families are usually led by a female dolphin. The dolphins in a family help each other, for example when raising their young. When travelling or hunting, several families might join together to make a larger group, a school of dolphins.
- the largest dolphin is the orca? It can reach up to ten metres in length. For more information on this dolphin, read our text about orcas.
- … dolphins have a thick layer of fat beneath their skin? This layer of fat is called blubber. As dolphins have no fur, they need the blubber to keep warm. Dolphins in colder waters usually have a thicker layer of fat than dolphins in warm waters.
- dolphins are endangered? Humans are the greatest threat to dolphins: environmental pollution, habitat destruction and overfishing are the main reasons why so many dolphin species are endangered. Lots of dolphins get stuck in fishing nets and in some countries, dolphins are deliberately killed because they eat the fish that the fishermen want to catch. If we do not do anything about it, dolphins might soon be extinct.
- not all dolphins live in seawater? There are some species that live in fresh water: the river dolphins. Unfortunately, river dolphins are critically endangered and it is even feared that one species, the baiji, has already died out.
- you can help to protect dolphins? Educate yourself about these animals and tell others about them. Care more about our environment and start to recycle more things. Raise money for an organisation that helps to support dolphins.
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