Wikipedia

Dolphin

This is an old revision of this page, as edited by PlatinumX (talk | contribs) at 02:19, 16 March 2004 (inserted classification table). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.


This article is about the dolphin mammal. For other uses of the term, please see dolphin (disambiguation).

Dolphin
a bottlenose dolphin

Dusky Dolphins

Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Cetacea
Family:Delphinidae


Dolphins are certain aquatic mammals related to whales and porpoises.

The word is used in a few different ways. It can mean:

  1. any member of the family Delphinidae (oceanic dolphins),
  2. any member of the families Delphinidae and Platanistoidae (oceanic and river dolphins),
  3. any member of the suborder Odontoceti (toothed whales; these include the above families and some others),
  4. laypeople often use the term synonymously with Bottlenose Dolphin, the most common and familiar species of dolphin.

Wikipedia uses definition 2 above.

Porpoises (suborder Odontoceti, family Phocoenidae) are thus not dolphins in our sense. Killer Whales and some related species belong to the Delphinidae family and therefore qualify as dolphins, even though they are called whales in common language.

There are almost 40 species of dolphin in 17 genera. They vary in size from 1.2 metres and 40 kg (Heaviside's Dolphin), up to 7 metres and 4.5 tonnes (the Killer Whale). Most species weigh between about 50 and about 200 kg. They are found worldwide, mostly in the shallower seas of the continental shelves, and all are carnivores, mostly taking fish and squid.

The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about 10 million years ago, during the Miocene.

Taxonomy

Six animals in the family Delphinidae are commonly called "whales" but are strictly speaking dolphins. They are sometimes called "blackfish":

Dolphin anatomy

still missing.

Dolphin behaviour

Dolphins are widely believed to be amongst the most intelligent of all animals, although the difficulties and expense of doing experimental work with a large marine animal, with a very different sensory apparatus from our own, mean that many of the tests required to confirm this belief have not yet been done, or have been carried out with inadequate sample sizes and methodology. See the Dolphin brain article for more details.

Dolphins are also famous for their willingness to occasionally approach humans and interact with them in the water. In return, in some cultures like in Ancient Greece treated with welcome, such as the idea of a ship spotting dolphins riding in their wake was considered a good omen for a smooth voyage.

Dolphin lore

The popular television show Flipper, created by Ivan Tors, portrayed a dolphin in a friendly relationship with two boys, Sandy and Bud; kind of a sea-going Lassie, he understood English unusually well and was a marked hero: "Go tell Dad we're in trouble, Flipper! Hurry!" The show's theme song contains the lyric no one you see/is smarter than he.

Releated Articles

Retrieved from "https://en.wikipedia.org/w/index.php?title=Dolphin&oldid=2820682"