I spent several hours doing this Wikipedia search & saving pics I hope you like it. Sadly I couldnt get the whole thing in 1 post so I had to break it down into 3.
There are tons of links that I didnt put in here so hee is the link to the entire article I used
http://en.wikipedia.org/wiki/Dolphin
Enjoy
Dolphin<Bottlenose Dolphin breaching in the bow wave of a boat>
Dolphins are aquatic 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 metres (4 ft) and 40 kilograms (88 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and ten tonnes (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 Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture
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Origin of the nameThe name is originally from Ancient Greek δελφίς (delphís; "dolphin"), which was related to the Greek δελφυς (delphys; "womb"). The animal's name can therefore be interpreted as meaning "a 'fish' with a womb".[1] The name was transmitted via the Latin delphinus, Middle Latin dolfinus and the Old French daulphin, which reintroduced the ph into the word.
The word is used in a few different ways. It can mean:
Any member of the family Delphinidae (oceanic dolphins),
Any member of the families Delphinidae and Platanistoidea (oceanic and river dolphins),
Any member of the suborder Odontoceti (toothed whales; these include the above families and some others),
Used casually as a synonym for Bottlenose Dolphin, the most common and familiar species of dolphin.
In this article, the second definition is used. Porpoises (suborder Odontoceti, family Phocoenidae) are thus not dolphins in this sense. Orcas and some closely related species belong to the Delphinidae family and therefore qualify as dolphins, even though they are called whales in common language. A group of dolphins can be called a "school" or a "pod".
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Taxonomy <Categories>Suborder Odontoceti, toothed whales
Family Delphinidae, oceanic dolphins
Genus Delphinus
<Common Dolphin>
Long-Beaked Common Dolphin, Delphinus capensis
Short-Beaked Common Dolphin, Delphinus delphis
Genus Tursiops
<Bottlenose>
Bottlenose Dolphin, Tursiops truncatus
Indo-Pacific Bottlenose Dolphin, Tursiops aduncus
Genus Lissodelphis
Northern Rightwhale Dolphin, Lissodelphis borealis
Southern Rightwhale Dolphin, Lissiodelphis peronii
Genus Sotalia
Tucuxi, Sotalia fluviatilis
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
<Spotted>
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 Cephalorynchus
Chilean Dolphin, Cephalorhynchus eutropia
<Commerson's>
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 Lagenorhyncus
Atlantic White-Sided Dolphin, Lagenorhynchus acutus
<DuskyDolphin>
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 aka Orca>
Killer Whale, 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
Family Platanistoidea, river dolphins
Genus Inia
<Boto>
Boto (Amazon River Dolphin), Inia geoffrensis
Genus Lipotes
Chinese River Dolphin (Baiji), Lipotes vexillifer (considered functionally extinct)
Genus Platanista
Ganges River Dolphin, Platanista gangetica
Indus River Dolphin, Platanista minor
Genus Pontoporia
La Plata Dolphin (Franciscana), Pontoporia blainvillei
Six species in the family Delphinidae are commonly called "whales" but are strictly speaking dolphins. They are sometimes called "blackfish".
Melon-headed Whale, Peponocephala electra
Killer Whale, Orcinus orca
Pygmy Killer Whale, Feresa attenuata Wolphin Kawili'Kai at the Sea Life Park in Hawaii.
False Killer Whale, Psudorca crassidens Long-finned Pilot Whale, Globicephala melas Short-finned Pilot Whale, Globicephala macrorhynchus
Hybrid dolphinsIn 1933, three abnormal dolphins were beached off the Irish coast; these appeared to be hybrids between Risso's Dolphin and the Bottlenose Dolphin. This mating has since been repeated in captivity and a hybrid calf was born. In captivity, a Bottlenose Dolphin and a Rough-toothed Dolphin produced hybrid offspring.A Common-Bottlenose hybrid lives at SeaWorld California. Various other dolphin hybrids have also been reported in the wild, such as a Bottlenose-Atlantic Spotted hybrid. The best known hybrid however is the Wolphin, a False Killer Whale-Bottlenose Dolphin hybrid. The Wolphin is a fertile hybrid, and two such Wolphins currently live at the Sea Life Park in Hawaii, the first having been born in 1985 from a male False Killer Whale and a female Bottlenose. Wolphins have also been observed in the wild.
<Wolphin>
A wholphin or wolphin is a rare hybrid, born from a mating of bottlenose dolphin Tursiops truncatus (mother), and a false killer whale Pseudorca crassidens (actually another dolphin species, taxonomically speaking). Although they have been reported to exist in the wild, there are currently only two in captivity, both at the Sea Life Park in Hawaii.
The first captive wholphin was born in 1985 where a female bottlenose dolphin and a male false killer whale shared a pool. The wholphin's size, color and shape are intermediate between the parent species. Named Kekaimalu, she has 66 teeth - intermediate between a bottlenose (88 teeth) and false killer whale (44 teeth).
The wholphin proved fertile when she gave birth at a very young age. Unfortunately, the calf died after a few days. However, in 1991, Kekaimalu gave birth once again, to daughter Pohaikealoha. For 2 years she cared for the calf, but did not nurse it (it was hand-reared by trainers). Pohaikealoha died at age 9.
On December 23, 2004, Kekaimalu had her third calf, daughter Kawili Kai, sired by a male bottlenose. This calf did nurse and was very playful. Only months after birth, it was the size of a 1-year-old bottlenose dolphin.
Both remain in captivity, and are not part of the normal tour at Sea Life Park. The backstage tour must be taken to see the wholphins. Keikaimalu is featured in the main dolphin show at Sea Life Park.
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Evolution and anatomyDolphins, along with whales and porpoises, are thought to be descendants of terrestrial mammals, most likely of the Artiodactyl order. The ancestors of the modern day dolphins entered the water roughly fifty million years ago, in the Eocene epoch.
{Hind Limb Buds on Dolphins An embryo of a Spotted Dolphin in the fifth week of development. The hind limbs are present as small bumps (hind limb buds) near the base of the tail. The pin is approximately 1 inch (~2,5 cm) long}
Modern dolphin skeletons have two small, rod-shaped pelvic bones thought to be vestigial hind legs. In October 2006 an unusual Bottlenose Dolphin was captured in Japan; it had small fins on each side of its genital slit which scientists believe to be a more pronounced development of these vestigial hind legs
Anatomy{The Anatomy of a Dolphin showing its skeleton, major organs and body shape}
.Dolphins have a streamlined fusiform body, adapted for fast swimming. The basic colouration patterns are shades of grey with a light underside and a distinct dark cape on the back. It is often combined with lines and patches of different hue and contrast.
The head contains the melon, a round organ used for echolocation. In many species, the jaws are elongated, forming a distinct beak; for some species like the Bottlenose, there is a curved mouth which looks like a fixed smile. Teeth can be very numerous (up to two hundred and fifty) in several species. The dolphin brain is large and has a highly structured cortex, which often is referred to in discussions about their advanced intelligence.
Unlike most mammals, dolphins do not have hair, but they are born with a few hairs around the tip of their rostrum which they lose after some time, in some cases even before they are born. The only exception to this is the Boto river dolphin, which does have some small hairs on the rostrum.
Their reproductive organs are located on the underside of the body. Males have two slits, one concealing the penis and one further behind for the anus. The female has one genital slit, housing the vagina and the anus. A mammary slit is positioned on either side of the female's genital slit.