Paleontology

Dinosaurs when did the dinosaurs roam the earth?

The following are depictions of the different types of dinosaurs and the approximate times they lived in different parts of the earth in contrast to the Biblical chronology of life existing on earth no earlier than 7 thousand years ago:
Source: http://dsc.discovery.com/convergence/dinosaurplanet/dinos/dinos2_zoom3.html

Carcharodontosaurus

Name Means: "Shark Lizard"
Time:Cretaceous (110-90 million years ago)
Location: Egypt, Morocco, Tunisia, Algeria, Libya, Niger

A massive meat-eater (larger than North America's Tyrannosaurus rex), Carcharodontosaurus was a heavy-boned, large-tailed, short-armed hunter with sharp claws on its three-fingered hands. This relatively primitive hunter grew 40 feet long, weighed 16,000 pounds, and had 8-inch-long teeth that could penetrate the toughest of prey. It probably took on even the largest of the large dinosaurs: the plant-eating giants called sauropods.

Maiasaura peeblesorum

Name Means: "Good Mother Lizard"
Time:Late Cretaceous (80-65 million years ago) Location: Montana

This duck-billed plant-eater got its name when fossils were found alongside eggs, nests and young. Paleontologists think a female laid about 25 grapefruit-sized eggs in a leaf-lined ground nest, and then cared for the young until they had at least doubled in size (Maiasaura was about a foot long at birth). Adults reached 30 feet long, 8 feet tall and weighed 8,000 pounds. They bred in large colonies and returned to the same nesting sites annually.

Troodon formosus

Name Means: "Wounding Tooth"
Time:Late Cretaceous (74-65 million years ago)
Location: Mexico, Canada, Montana, Wyoming

With the largest brain of any dinosaur in proportion to its size, this was perhaps one of the smartest dinosaurs. And with excellent vision and long, serrated teeth, this scaly-skinned, fast, light theropod must have been a deadly night hunter. Standing as tall as an adult human and reaching weights of roughly 110 pounds, it had very dexterous hands and probably fed on relatively small prey including mammals, lizards, insects and perhaps newborn dinosaurs.

Daspletosaurus torosus

Name Means: "Frightful Fleshy Lizard"
Time:Late Cretaceous (70-68 million years ago)
Location: Canada; Montana

A massive dinosaur, its teeth larger than that of its larger cousin T. rex, Daspletosaurus was nearly 30 feet long and weighed 6,000 pounds. Its teeth were curved like daggers, and serrated, and it may have fed on the armored ceratopids.

Einiosaurus procurvicornis

Name Means: "Buffalo Lizard" (in Sioux)
Time:Late Cretaceous (70-65 million years ago)
Location: Montana

Discovered in 1994, the 25-foot-long herbivore had a frill spouting a pair of spikes, a massive nose horn and a pair of smaller horns above its eyes. As with many recent dinosaur discoveries, much is still to be determined about how it lived.

Aucasaurus garridoi

Name Means: "Auca Lizard"
Time:Late Cretaceous (80 million years ago)
Location: Argentina

Aucasaurus was just described in 1999, based on what could be the most complete skeleton ever found for a member of the Abelisaur genus. It has bumps (not horns) on its skull. This meat-eater would have been about 13 feet long and would have weighed some 1,500 pounds.

Carcharodontosaurus

Name Means: "Shark Lizard"
Time:Cretaceous (110-90 million years ago)
Location: Egypt, Morocco, Tunisia,
Algeria, Libya, Niger

A massive meat-eater (larger than North America's Tyrannosaurus rex), Carcharodontosaurus was a heavy-boned, large-tailed, short-armed hunter with sharp claws on its three-fingered hands. This relatively primitive hunter grew 40 feet long, weighed 16,000 pounds, and had 8-inch-long teeth that could penetrate the toughest of prey. It probably took on even the largest of the large dinosaurs: the plant-eating giants called sauropods.

Notosuchid

Time:Cretaceous (80 million years ago)
Location: Uruguay; Madagascar

Notosuchid was a 5-foot-long, 80-pound terrestrial crocodilian with a powerful bite. In form and function, it would have resembled something between a crocodile and a large land lizard. Notosuchid didn't drag its tail behind it, but rather held it up as it walked. It likely was a food source for some meat-eating dinosaurs, and perhaps a predator, feeding on the eggs of other dinosaurs.

Amateur paleontologists carefully prepare dinosaur bones at a site in western Colorado. Pictures:Courtesy Museum of Western Colorado. Teeth of the dinosaur under excavation.

Paleontologist and fossil dealer Peter Larson poses with the massive skull of "Sue," now on permanent display at Chicago's Field Museum of Natural History.
Picture: by Layne Kennedy/Corbis

Dinosaur Cannibal: Fossil Evidence Found in Africa
Four teeth and a bitten bone of Majungatholus atopus. Tooth marks scored into bones match the size and spacing of teeth found in Majungatholus jaws. In addition, fine tooth serrations match grooves notched into fossil bones.

Representative sample of tooth-impacted Majungatholus
atopus bones: A) Caudal vertebra with set of parallel tooth marks (arrows) on anterior edge of neural spine; B) Chevron with set of parallel tooth marks (arrows) on posterior margin;C) Chevron with set of four parallel tooth marks (black arrows), deep tooth gouges, and denticle drag marks (white arrows); D) Chevron gouged with denticle drag marks (right lateral view, arrow) and deep tooth drag (left-lateral view); E) Transverse process with multiple tooth marks (arrows). Scale bar is 1 centimeter (0.4 inches).

Reconstruction of Paralititan stromeri, a new, giant sauropod dinosaur from Upper Cretaceous mangrove deposits in Egypt. Courtesy of Cosmos Studios/MPH Entertainment/
Computer Graphic by Rainbow Studios
"Tidal Giant" Roamed Coastal Swamps of Ancient Africa

By John Roach for National Geographic News: May 31, 2001

Researchers have unearthed fossils of what appears to have been the second largest known creature ever to walk on Earth. The dinosaur, named Paralititan stromeri weighed in at an estimated 75 tons and measured as long as 100 feet (30.5 meters).

It dwelled 94 million years ago in mangrove swamps that once covered what is now a remote desert area in western Egypt.

The partial skeleton of Paralititan included an upper arm bone 1.69 meters (5.5 feet) long. By comparing it with other fossils, the scientists concluded that Paralititan was the second largest dinosaur ever found, exceeded in size only by Argentinosaurus, which lived at the same time in an area of what is now Argentina.

The discovery of these and other large vertebrate fossils in Egypt lends credence to a theory that Africa and South America were part of the same land mass during the Late Cretaceous period (146 to 65 million years ago), said Thomas Holtz, a vertebrate paleontologist at the University of Maryland in College Park.

Scientists have found groups of vertebrates that were common to South America and Madagascar during the Late Cretaceous, but these same groups have appeared to be missing from Africa.

One possible explanation for the mysterious absence is that Africa may have split apart from South America before the late Cretaceous. A second explanation holds that the two continents were still attached through the Late Cretaceous, but relatively few dinosaur fossils have been discovered in Africa because research in the area has been limited.

"This discovery is consistent with the second model," said Holtz, adding that Paralititan seems to be closely related to Argentinosaurus.

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