Dinosaurs

Millions of years ago, long before there were any people, there were amazing creatures, giants and heavy, dangerous and weird; those were the fabulous dinosaurs. Dinosaurs were one of several kinds of prehistoric reptiles that lived during the Mesozoic Era, the "Age of Reptiles," were dinosaurs were the kings.

The dinosaurs dominated the Earth for over 165 million years during the Mesozoic Era, but mysteriously went extinct 65 million years ago.The most accepted theory is that an asteroid crashed into the earth at the Yucatan peninsula, in Mexico. Paleontologists (Who are people who search about prehistoric life) study their fossil remains to learn about the amazing prehistoric world of dinosaurs.




Dinosaurs first appeared first in the Triasic period like 230 million years ago; the oldest known dinosaur is Eoraptor, who appeared 228 million years ago. Dinosaurs disappeared in the Cretacic period 65 million years ago.

The word  "dinosaur" means "terrible lizard"; this name was created by english anatomist Sir Richard Owen at the ninetheenth century after discovering Iguanodon.







The largest dinosaurs were over 100 feet (30 m) long and up to 50 feet (15 m) tall (like Argentinosaurus, Seismosaurus, Ultrasauros, Brachiosaurus, and Supersaurus). The smallest dinosaurs, like Compsognathus, were about the size of a chicken. Most dinosaurs were in-between.

Dinosaurs evolved from other 

reptiles (socket-toothed

 archosaurs) during the Triassic

 period, over 230 million years

 ago. Dinosaurs evolved soon 

after the Permian extinction,

 which was the biggest mass 

extinction that ever occured 

on Earth. During this time

(the Triassic period), the 

mammals also evolved.

It is very difficult to figure        
out how the dinosaurs 
sounded, how they 
behaved, how they mated,
 what color they were, or
 even how to tell whether
 a fossil was male or 
female.





There were lots of different kinds of dinosaurs that lived at different times.

• Some walked on two legs (they were bipedal), some walked on four (they were quadrupedal). Some could do both.
• Some were speedy (like Velociraptor), and some were slow and lumbering (likeAnkylosaurus).
• Some were armor-plated, some had horns, crests, spikes, or frills.
• Some had thick, bumpy skin, and some even had primitive feathers.

Dinosaurs probably live on today as the birds. All that's left of the dinosaurs are fossils and, perhaps,the birds. Dinosaur fossils have been found all over the world, maybe even near where you live!



Thanks to:
http://www.enchantedlearning.com/subjects/dinosaurs/