Dinosaurs first appeared about 230 million years ago. these amazing reptiles then dominated life on Earth until they become extinct 65 million years ago. The first dinosaurs to be described were Megalosaurus (great lizard ) by William Buckland in 1824 and Iguanodon (iguanua tooth) by GideonMantell in 1825.
They were named before the word "dinosaur" had been invented. The name dinosauria (terrible lizard)was suggested by british scientist Richard Owen in july 1841. Since then 700 specie have been identified. Not all dinosaurs were enormous- some measured less than 60 cm(24 in) are mostly estimates worked out from the size of Brachiosaurus and 22.3 m (73.2 ft) long. The skelton is in the Humblodt museum, berli, germany.
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| Tyrannosaurus rex |
Dianosaur facts
- The biggest dinosaurs were all herbivores. Tyrannosaurus rex, one of the largest carnivorous dinosaurs, measured up to 15 m(49.2 ft) long and weighed 60,000 kg (132,277 lb) or more. its huge jaws were packed with 60 teeth, the biggrst of which were 23 cm ( 9 in) long !.
- A new type of tyrannosaur called Guanlong wucaii has recently been discovered in China. it lived 160 million years ago, measured about 3 m (10 ft) long, and looked like a miniature version of Tyrannosaurus rex.
- The largest flying prehistoric creatures were pterosaurd.
- The wings of the biggest pterosaur,Quetzalcoatlus, measured 10.96 m(36 ft) from tip to tip.
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| Quetzalcoatlus |
- The largest known dinosaur egg belonged to Hypselosaurus. The 100 million-years-old egg measures 30 by 25.5 cm (12 by 10 in), about three times the volume of an ostrich egg.
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| Hypselosaurus |
- The fastest dinosaur, Ornithomimus, could probably run at speed of up to 70 km/h (43.5 mph). The ostrich runs at a similar speed today.
- Dinosaurs have been in space! Fragments of bone and an eggshell of Maiasaura peeblesorum were taken into space by astronaut Loren Action in1985. A Coelophysis skull was taken into space by astronaut Bonnie Dunbar in1998.
