Dolphins have a "fusiform" body wide in the middle, tapered at the ends adapted for fast swimming. The head contains the melon, a round organ used for echolocation. In many species, the jaws are elongate, forming a distinct beak and for some species like the Bottlenose, the curved mouth that looks like a fixed smile. Teeth can be very numerous in several species. The dolphin brain is large and has a highly structured cortex, which is often referred to in discussions about their high intelligence.
The basic coloration pattern are shades of gray with a light underside and a distinct dark cape on the back. Markings are often combined with lines and patches of different hue and contrast.
A) Dorsal Fin: The dorsal
fin is falcate (curved back) and located at the center
of the back. It is made up of fibrous tissue. It may act to stabilize
the dolphin as it swims but it is not a necessity - as some dolphin’s
dorsal fins are damaged with some almost
B) Melon: The fatty, rounded structure
on the top of the head used to produce sounds for communication and
C) Rostrum: The snout of the dolphin containing conical shaped teeth. These interlock to catch prey whole and suck it down whole, without chewing it.
D) Pectoral Flippers: The pectoral flippers are the dolphin’s forelimbs. They are very similar to our forearms and hands. The flippers are curved and pointed on the ends and have a primary function of helping the dolphin to steer.
E) Postanal Hump: The hump is found only on mature males.
Blowhole: Dolphins breathe air, and must come up to the surface of the water regularly. They only have one nostril, located on the top of their headm called the blowhole. It is used by the dolphin to breathe, but they have no sense of smell!
Tail Fluke: A Dolphin's tail has two lobes called flukes. These flukes are flat, and made up of fibrous tissue. There is no bone or muscle. The tail fluke is used for swimming by the back muscles moving the fluke up and down.