Characteristics of Dolphins Essay -- Exploratory Essays Research Paper

Characteristics of Dolphins The majority of small tooth whales are called dolphins.   â€Å"Dolphins are mammals of the order Cetacean and the families Plantanistidae and Delphinidae and include about 50 species† (Internet 1).   Most dolphin species are about 6 feet in length, the males averaging 4 to 8 inches longer than females. The longest dolphin, the bottle-nose dolphin, can reach over nine-feet in length and weight up to 440 pounds. The smallest dolphin species is the buffalo which is found in the Amazon River. The Buffalo dolphin rarely grows over 3.9 feet or weighs more than 66 pounds. A dolphin’s diet consists mainly of herring, mackerel, and sardines. â€Å"Some species however, prefer squid, shrimp and other crustacean† (Gygax 585). The average amount of fish ingested is estimated at about 66 pounds a day for an individual dolphin about 8.2 feet and 220 pounds. The body of a dolphin is sleek, smooth and hairless, making the skin rubbery to the touch.   Most species have jaws that protrude into a beak like snout.   â€Å"Above the upper jaw is a large mass of fat and oil-containing tissue forming the so-called "melon" that looks much like a bulging forehead† (Internet 1). The dorsal fin on the mid-back of the dolphin contains the skeletal remnants of five digits that form the flippers. Dolphins use the dorsal fin primarily as stabilizers, although occasionally in an oar like fashion.   The dorsal fin is formed from subcutaneous dermal tissue and is not movable by muscle action.   The hind flippers consist of a pair of small pelvic bones, deeply embedded in the connective tissue at the base of the tail.   The caudal, or tail, fin is also primarily dermal in origin, rather than skeletal, and con... ... the rough-toothed Dolphin, the Bottlenose Dolphin, the Atlantic White-Sided Dolphin, the Pacific White-Sided Dolphin, the Common Dolphin, the Spotted Dolphin, the Striped Dolphin, and the Black Dolphin (low, rounded dorsal fin; no beak; dark pigmentation; limited to the coastal waters of Chile.) Sources Cited Gygax, Lorenz. â€Å"Evolution of Group Size in the Dolphins and Porpoises: Interspecific Consistency of Intraspecific Patterns.† Behavioral Ecology. Vol. 13, No. 5 (Sept 2002): 583-590. Hamilton, Healy, et al. â€Å"Evolution of River Dolphins.† The Royal Society. California: 549-555. Internet 1 http://www.thedolphinplace.com/facts.html <http://www.beach-net.com/dolphins/biology.html> <http://www.liscannorferry.com/dolphin_jewelry-1.html> <http://thedolphinplace.com/main.html> <http://laws.fws.gov/lawsdigest/marman.html> Characteristics of Dolphins Essay -- Exploratory Essays Research Paper Characteristics of Dolphins The majority of small tooth whales are called dolphins.   â€Å"Dolphins are mammals of the order Cetacean and the families Plantanistidae and Delphinidae and include about 50 species† (Internet 1).   Most dolphin species are about 6 feet in length, the males averaging 4 to 8 inches longer than females. The longest dolphin, the bottle-nose dolphin, can reach over nine-feet in length and weight up to 440 pounds. The smallest dolphin species is the buffalo which is found in the Amazon River. The Buffalo dolphin rarely grows over 3.9 feet or weighs more than 66 pounds. A dolphin’s diet consists mainly of herring, mackerel, and sardines. â€Å"Some species however, prefer squid, shrimp and other crustacean† (Gygax 585). The average amount of fish ingested is estimated at about 66 pounds a day for an individual dolphin about 8.2 feet and 220 pounds. The body of a dolphin is sleek, smooth and hairless, making the skin rubbery to the touch.   Most species have jaws that protrude into a beak like snout.   â€Å"Above the upper jaw is a large mass of fat and oil-containing tissue forming the so-called "melon" that looks much like a bulging forehead† (Internet 1). The dorsal fin on the mid-back of the dolphin contains the skeletal remnants of five digits that form the flippers. Dolphins use the dorsal fin primarily as stabilizers, although occasionally in an oar like fashion.   The dorsal fin is formed from subcutaneous dermal tissue and is not movable by muscle action.   The hind flippers consist of a pair of small pelvic bones, deeply embedded in the connective tissue at the base of the tail.   The caudal, or tail, fin is also primarily dermal in origin, rather than skeletal, and con... ... the rough-toothed Dolphin, the Bottlenose Dolphin, the Atlantic White-Sided Dolphin, the Pacific White-Sided Dolphin, the Common Dolphin, the Spotted Dolphin, the Striped Dolphin, and the Black Dolphin (low, rounded dorsal fin; no beak; dark pigmentation; limited to the coastal waters of Chile.) Sources Cited Gygax, Lorenz. â€Å"Evolution of Group Size in the Dolphins and Porpoises: Interspecific Consistency of Intraspecific Patterns.† Behavioral Ecology. Vol. 13, No. 5 (Sept 2002): 583-590. Hamilton, Healy, et al. â€Å"Evolution of River Dolphins.† The Royal Society. California: 549-555. Internet 1 http://www.thedolphinplace.com/facts.html <http://www.beach-net.com/dolphins/biology.html> <http://www.liscannorferry.com/dolphin_jewelry-1.html> <http://thedolphinplace.com/main.html> <http://laws.fws.gov/lawsdigest/marman.html>