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Phylum: Chordata
Subphylum: Vertebrata
Class: Mammalia
Order: Cetacea
Suborder: Odontoceti (toothed whales)
The bottlenose dolphin, known by its scientific name as Tursiops truncatus,
is the species of dolphin most often found in captive exhibits and swim
programs.
Bottlenose dolphins have a sleek, streamlined, aerodynamic shape.
The pigment of a dolphins back allows it to blend into its
aquatic surroundings. Most fall along a spectrum between gray and blue.
The abdomen is white and can be somewhat pink.
A blowhole, on the dorsal surface of the head, is the mechanism
through which a dolphin breathes. To breathe, a dolphin contracts the
muscle flap covering the hole, thus opening it. When the flap is relaxed,
the blowhole closes, keeping water from entering the dolphins system.
Bottlenose dolphins from the Atlantic Ocean can reach an average
of 2.5 to 2.7 m (8.2-8.9 ft.) and weigh between 190 and 260 kg. (419-573
lb.)
Bottlenose dolphins from the Pacific Ocean can reach 3.7 m (12
ft.), with an average weight of 454 kg. (1,000 lb.). In the Mediterranean,
they can grow up to 3.7 m (12 ft.) or more.
Typically, well-developed males are slightly larger than females
and considerably heavier. However, young females grow more quickly than
males until they reach the age of10 years.
Humans are the only known enemy of these animals. In particular, the tuna
fishing industry has had a profoundly negative effect on the species
survival rates. Since dolphins usually accompany schools of yellow-fin
tuna, they are often caught and perish in tuna nets.
Bottlenose dolphins are also hunted as food source, used as shark bait
or taken alive to be trained for circus shows in some parts of the world,
though there is a growing trend towards protective legislation for dolphins.
The dolphin is considered the most intelligent animal of the aquatic environment,
and among the most intelligent animals on the planet.
A dolphins dominant sense is echolocation. Acoustical clicks
reverberate back to the dolphin, giving it a very clear picture of its
surroundings. Echolocation allows a dolphin to locate food and detect
obstacles and other creatures under almost any condition.
Dolphins are very curious, strong and physically resilient. Bottlenose
dolphins spend much of their time playing and interacting with their pod
members. It is highly sociable and usually sighted in groups of 5, 7 or
more. Pods are structured around a matriarchal system.
Dolphins frequent bays and coastlines, usually in depths under 20 meters.
While some pods take up permanent residence and establish home waters,
others are migratory and swim considerable distances from coast to coast.
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