cetacean summary

Know about the classification and physical features of cetaceans

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Below is the article summary. For the full article, see cetacean.

species of whales
Whales (order Cetacea).

cetacean , Any of the exclusively aquatic placental mammals constituting the order Cetacea. They are found in oceans worldwide and in some freshwater environments. Modern cetaceans are grouped in two suborders: about 70 species of toothed whales (Odontoceti) and 13 species of toothless baleen whales (Mysticeti). They have a tapered body, no external hind limbs, and a tail ending in a horizontal blade of two lobes, or flukes. Cetaceans must come to the water’s surface to breathe through blowholes located on top of their head. See also whale.

whale Summary

Whale, any of the larger species of aquatic mammals belonging to the order Cetacea. The term whale can be used in reference to any cetacean, including porpoises and dolphins, but in general it is applied to those more than 3 metres (10 feet) long. An exception is the 2.7-metre dwarf sperm whale

Dolphins (family Delphinidae) and river dolphin (family Platanistidae).

dolphin Summary

Dolphin, any of the toothed whales belonging to the mammal family Delphinidae (oceanic dolphins) as well as the families Platanistidae and Iniidae, the two that contain the river dolphins. Of the nearly 40 species of dolphins in the Delphinidae, 6 are commonly called whales, including the killer