The largest and the oldest

Feb 28, 2008 15:13 GMT  ·  By

180 Ma ago, northern dinosaurs were separated, on a supercontinent called Laurasia, from the southern dinosaurs, located on a supercontinent called Gondwana. About 10 new species of dinosaurs are found annually, and the hotbed of southern dinosaur discoveries is represented by Patagonia (the southern part of Argentina).

1. Argentinosaurus is the largest dinosaur ever found. It was a sauropod that could reach 35 m (115 ft) in length and a weighed 80 to 100 tonnes. More recent estimations point to a size of up to 26 m (85 ft). It lived 100 Ma ago, and its relatives were found in Africa, Asia and North America. By 146 Ma ago, its relatives were extinct in North America, but the line survived longer in the south.

2. Giganotosaurus lived 93 to 89 million years ago. This is the first carnivore dinosaurs found to be larger than Tyrannosaurus (amongst carnivorous dinosaurs, only Spinosaurus of Africa was larger). Similar species were found in Africa (they form the family called Carcharodontosauridae or shark-toothed dinosaurs). Giganotosaurus could be 13.2 m (43.3 ft) long and weigh 6.2 tons.

3. Carnotaurus was a large carnivorous dinosaur, with horns like those of a cow. It lived 70 Ma ago, and its relatives lived in Africa, Madagascar and India.

Carnotaurus was up to 9 m (30 ft) in length, 3.5 m (10 ft 7 in) tall and weighed 1.76 tons. This dinosaurs had extremely reduced forelimbs, with four fingers. The skull and tail were thin. The forward faced eyes pointed to binocular vision.

4. Kritosaurus is the only known duck-billed dinosaur in South America, where it lived 73 million years ago. Various duck-billed dinosaurs were found in North America.

5. Gasparinisaura was a tiny herbivorous dinosaur that lived 70 Ma ago, related to Iguanodons. Its relatives lived in Africa, North America and Europe.

6. Patagonykus was a carnivorous dinosaur that lived 70 Ma ago. It was 2 m (6.6 ft) long and similar species were found in Mongolia. It had a body like an ostrich, a crocodile-like tail and a large fearful claw at each limb.

7. Amargasaurus was an odd sauropod dinosaur that lived 100 Ma ago. It reached 10 m (33 ft) in length and had two parallel rows of tall spines down its neck and back, much higher than in any other sauropod, which could support skin sails.

8. Eoraptor lived between 230 and 225 million years ago and could be the oldest known dinosaur. It was about 1 m (3 ft) in length, weighing 10 kg (22 pounds). It ran digitigrade and bipedally. It was probably omnivorous.

9. Herrerasaurus was one of the earliest dinosaurs, living 228 million years ago. It was an early carnivorous dinosaur, up to 6 m (20 ft) long and weighing 350 kg (772 lb).

Photo Gallery (9 Images)

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