Author: James Hayes
The Megalodon is the deadliest prehistoric animal that ever roamed the seas. The Megalodon is an extinct species of shark which was about 59 feet (18 meters) long and hunted in the seas until about 1.5 million years ago. It was similar to today's great white shark, but three times longer and 20 times heavier. Megalodon had more than 250 huge, razor-sharp teeth and its mouth was so huge that it could easily swallow a person. The fossils of its teeth were once thought to be the tongues of dragons or similar beasts.
The Sabre-toothed Cat, also called Sabre-toothed Tiger, were any of the extinct cat-like carnivores belonging to either the extinct family Nimravidae or the subfamily Machairodontinae of the cat family. Named for their pair of elongated, blade-like canine teeth in their upper jaw, they are often called Sabre-toothed Tigers, or Sabre-toothed Lions. The modern lion and tiger are true cats of the subfamily Felinae.
Titanoboa (Titanoboa cerrejonensis) is an extinct snake that lived during the Paleocene period, which is 66 to 56 million years ago. It is considered to be the largest known member of the suborder Serpentes. Titanoboa is known from several fossils that date back to 58 to 60 million years ago. From extrapolations of body size made from excavated vertebrae (individual sections of the backbone) paleontologists have estimated that the body length of the average adult Titanoboa was roughly 13 meters (42.7 feet) long and an average weight of 1,135 kilograms (1.25 tons). Titanoboa is related to living anacondas and boas, but it is uncertain whether it was more closely related to one or another of these modern constrictor snakes.
Spinosaurus is a genus of Theropod dinosaur that lived in what is now North Africa during the lower Albian to lower Cenomanian stages of the Cretaceous period. This was about 112 to 97 million years ago.
Tyrannosaurus, meaning "tyrant lizard", from the ancient Greek tyrannos, "tyrant", and sauros, "lizard" is a genus of Coelurosaurian Theropod dinosaur. It had a tremendous bite force, the strongest of any dinosaur and living terrestrial animal. Its bite force reached up to 12,800 pounds (roughly 5805 Kilograms).
the Wooly Mammoth (genus Mammuthus) was any member of an extinct group of elephants. They were found as fossils in Pleistocene deposits over every continent except Australia and South America, and in the early Holocene deposits of North America. The Pleistocene epoch began 2.6 million years ago and ended 11,700 years ago. The Holocene epoch began 11,700 years ago and continues to the present.
All we know about the Andrewsarchus amounts to a single, three-foot-long, vaguely wolf-shaped skull that was discovered in Mongolia in 1923. While the skull clearly belongs to some type of mammal, there are obvious diagnostic markers by which paleontologists can distinguish between reptilian and mammalian bones. The lack of an accompanying skeleton has resulted in nearly a century of confusion and debate about what type of animal the Andrewsarchus really was.
Liopleurodon is a genus of large, carnivorous marine reptiles belonging to the Pliosauroidea, a clade of short-necked Plesiosaurs. The two species of Liopleurodon lived during the Callovian stage of the middle Jurassic period.
Mosasaur (family Mosasauridae) is an extinct aquatic lizard that attained a high degree of adaptation to its marine environment and was distributed worldwide during the Cretaceous Period (145.5 to 65.5 million years ago). The Mosasaurs competed with other marine reptiles—the plesiosaurs and ichthyosaurs—for food, which consisted largely of ammonoids, fish, and cuttlefish. Many Mosasaurs of the Late Cretaceous were large, exceeding 9 meters (30 feet) in length, but the most common forms were no larger than modern porpoises.
Megatherium, largest of the ground sloths, is an extinct group of mammals belonging to a group containing sloths, anteaters, glyptodonts, and armadillos. This group of mammals underwent a highly successful evolutionary radiation in South America during the Cenozoic Era (beginning 65.5 million years ago). The size of these animals approximated that of a modern elephant, and they were equipped with large claws and teeth; the latter were confined to the sides of the jaw because the animal fed largely on the leaves of trees and bushes. Ground sloths appeared briefly in North America during the Pleistocene Epoch (2.6 million to 11,700 years ago) when a land connection was established between the American continents.