| Dolphins (Latin: Delphinidae) — aquatic mammals belonging to order “cetacean” (whales), suborder “odontoceti” (large-toothed whales) (Denticete). Dolphins are characterized by the presence of fairly sufficient number of uniform teeth (88 teeth) in both the jaws; both the nostrils are joined usually at a single lateral hole of semi lunar shape. Head of the dolphins is relatively small usually with pointed face; elongated body; mainly exists dorsal fin. Dolphins are very lively, swift, voracious predators, living mainly in pods (group of individuals); found in all seas and raise high even in rivers. Fish and squid are the main source of food for most dolphin species; sometimes attack and feed on their relatives (marine mammals). Dolphins are differentiated even by intellectual curiosity and traditionally good behavior towards human being.
For some dolphins, the snout is extended forward in the form of a beak У (family Platanista, Inia, Delphinus); for some dolphins, the head is round-shaped from front side without beak-shaped snout (Phocaena, Orca (killer whale), Globicephalus (pilot whale), Delphinapterus (white whale)).
Dolphins swim extremely fast. Dolphin pods often follow steamers and ships. Dolphin was lovable and extremely popular animal in ancient times; Many poetic legends and believes were composed about dolphins (Legend about Arion); often represented in sculpture.
Gestation period of dolphins is around 10—18 months. Usually, female dolphin gives birth to a single calf, which is 50-60 cm length, and carefully protects the calf for sometime. Apparently, reproductive senescence (old-age) is very slow in dolphins and lifespan of dolphins is fairly more.
Dolphins possess developed sound signalization and echolocation system. Contrary to the widespread opinion, authenticated information about the existence of special dolphin “language” is absent, even though, group of American researchers established that the dolphins are capable of understanding and identifying the names. In June 2005, cultural aspect of dolphins was established through combined efforts of American, Canadian and Australian researchers. Some dolphins teach their children to use tools. The knowledge to use the tools is mostly transferred from mothers to daughters.
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