Dinosaurs
Information about Dinosaurs:
Dinosaurs were a large, diverse group of extinct animals that dominated the earth for about 160 million years. Generally, is it believed they lived from the late Triassic period (about 230 million years ago) until the end of the Cretaceous (about 65 million years ago). It is believed that climate change which was caused by a massive meteor strike in what is now the Yucatan Peninsula caused them, along with 90% of all animals on the planet, to go extinct.
Fossil records point to the dinosaurs being the ancestors to modern birds, and that they evolved within theropod dinosaurs during the Jurassic period. Dinosaurs remains have been found on every continent. The largest land animals ever to live were dinosaurs. Many were herbivorous while others carnivorous. There were some animals who moved on two legs (bipedal) and some on four (quadrupedal) Some shifted between these. During this times there were even flying dinosaurs called Pterosaurs. While many of the dinosaurs were massive, hulking animals weighing many tons, some were very small – only a few feet long at most.
Most groups of dinosaurs are known to have built nests and laid eggs. When dinosaur bones were first discovered in the 17th century in England, scientists began to piece together what they were and how they might have lived. For many decades, dinosaurs were believed to be slow moving, lumbering animals. But in the last few decades, researchers have begun to put together a much different picture; that dinosaurs were active, quick animals with high metabolisms and numerous specialized adaptations for social interaction.
Over the years, scientists have had to change their attitudes towards these animals, as more and more evidence comes to light showing these extinct animals to be anything but the sluggish, slow-witted animals they were once believed to be.