Post by Deinobrontornis on Feb 24, 2012 18:54:40 GMT -5
Tyrannosaurus - Tyrannosaurus rex
Tyrannosaurus is a genus of theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 67 to 65.5 million years ago. It was among the last non-avian dinosaurs to exist prior to the Cretaceous–Tertiary extinction event.
Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs were small, though unusually powerful for their size, and bore two clawed digits. Although other theropods rivaled or exceeded Tyrannosaurus rex in size, it was the largest known tyrannosaurid and one of the largest known land predators, measuring up to 12.8 meters (42 ft) in length, up to 4 meters (13 ft) tall at the hips, and up to 6.8 metric tons (7.5 short tons) in weight. By far the largest carnivore in its environment, Tyrannosaurus rex may have been an apex predator, preying upon hadrosaurs and ceratopsians, although some experts have suggested it was primarily a scavenger. The debate over Tyrannosaurus as apex predator or scavenger is among the longest running in paleontology.
African Bush Elephant - Loxodonta africana
The African Elephant is the largest living terrestrial animal, normally reaching 6 to 7.3 metres (19.7 to 24.0 ft) in length and 3.5 to 4 metres (11.5 to 13.1 ft) in height at the head, and weighing between 6,000 to 9,000 kg (13,000 to 20,000 lb).
The largest on record, shot in Angola in 1955, was a bull weighing 12,274 kg (27,060 lb)[citation needed] and standing 4.2 metres (13.8 ft) high, the body of which is now mounted in the rotunda of the National Museum of Natural History in Washington, D.C.. (The museum's website states that the specimen weighs only 8 tons.) The Bush Elephant normally moves at a rate of 6 km/h (4 mph), but it can reach a top speed of 40 km/h (25 mph) when scared or upset.
The animal is characterized by its large head; two large ears that cover its shoulders and radiate excess heat; a large and muscular trunk; two prominent tusks, which are well-developed in both sexes, although more commonly in males; a short neck; a large, barrel-like body; four long and heavy legs; and a relatively short tail.
The animal is protected by a heavy but flexible layer of gray-brown skin, dotted with mostly undeveloped patches of hair and long, black hair at the tip of its tail. Its back feet have three toes that form a hoof, while the number of toes on the front feet have varied between four and five. The forehead is smoother and less convex than that of the Asian Elephant.
The trunk is the most characteristic feature of the African Bush Elephant. It is formed by the fusion and elongation of the nose and upper lip, forming a flexible and strong organ made purely of muscle.
Little scientific research has been carried out into elephants' cognitive or perceptual abilities. An exception is a recent report that African Bush Elephants are able to use seismic vibrations at infrasound frequencies for communication.
Tyrannosaurus is a genus of theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 67 to 65.5 million years ago. It was among the last non-avian dinosaurs to exist prior to the Cretaceous–Tertiary extinction event.
Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs were small, though unusually powerful for their size, and bore two clawed digits. Although other theropods rivaled or exceeded Tyrannosaurus rex in size, it was the largest known tyrannosaurid and one of the largest known land predators, measuring up to 12.8 meters (42 ft) in length, up to 4 meters (13 ft) tall at the hips, and up to 6.8 metric tons (7.5 short tons) in weight. By far the largest carnivore in its environment, Tyrannosaurus rex may have been an apex predator, preying upon hadrosaurs and ceratopsians, although some experts have suggested it was primarily a scavenger. The debate over Tyrannosaurus as apex predator or scavenger is among the longest running in paleontology.
African Bush Elephant - Loxodonta africana
The African Elephant is the largest living terrestrial animal, normally reaching 6 to 7.3 metres (19.7 to 24.0 ft) in length and 3.5 to 4 metres (11.5 to 13.1 ft) in height at the head, and weighing between 6,000 to 9,000 kg (13,000 to 20,000 lb).
The largest on record, shot in Angola in 1955, was a bull weighing 12,274 kg (27,060 lb)[citation needed] and standing 4.2 metres (13.8 ft) high, the body of which is now mounted in the rotunda of the National Museum of Natural History in Washington, D.C.. (The museum's website states that the specimen weighs only 8 tons.) The Bush Elephant normally moves at a rate of 6 km/h (4 mph), but it can reach a top speed of 40 km/h (25 mph) when scared or upset.
The animal is characterized by its large head; two large ears that cover its shoulders and radiate excess heat; a large and muscular trunk; two prominent tusks, which are well-developed in both sexes, although more commonly in males; a short neck; a large, barrel-like body; four long and heavy legs; and a relatively short tail.
The animal is protected by a heavy but flexible layer of gray-brown skin, dotted with mostly undeveloped patches of hair and long, black hair at the tip of its tail. Its back feet have three toes that form a hoof, while the number of toes on the front feet have varied between four and five. The forehead is smoother and less convex than that of the Asian Elephant.
The trunk is the most characteristic feature of the African Bush Elephant. It is formed by the fusion and elongation of the nose and upper lip, forming a flexible and strong organ made purely of muscle.
Little scientific research has been carried out into elephants' cognitive or perceptual abilities. An exception is a recent report that African Bush Elephants are able to use seismic vibrations at infrasound frequencies for communication.