More Dinosaur Information

More than 210 million years ago, a new group of animals appeared on Earth. They were the dinosaurs. These creatures originated from microscopic marine organisms through the processes for genetic change and natural selection. In the Paleozoic era (about 570-248 million years ago), soft-bodied creatures gave rise to fish with internal bony skeletons. Fish produced amphibians, which in turn gave rise to reptiles. One group of reptiles evolved into dinosaurs.

When dinosaurs first appeared on Earth, all the continents were joined together into one huge land mass called Pangaea. Without wide bodies of water to block their paths, dinosaurs wandered freely across the continents. By the end of the Triassic period, 208 million years ago, Pangaea was breaking into two land masses - Laurasia and Gondwana.

Digging Dinosaurs

When an animal dies, the remains are usually destroyed by weather or other animals. Sometimes, however, the bodies are washed into a river or lake and quickly covered in sand and mud.  In the desert, the remains might be covered by wind-blown sands. Over millions of years, more sand and mud were piled on top of the remains. Sediments gradually turned into sandstone, limestone, and shale, any soft body parts rotted away, leaving bones and teeth to become fossils.

EGGxactly

Fragile fossilized eggs have been discovered at several dinosaur excavation sited. The eggs are often found in nests, with remains of the parent dinosaurs nearby.

Claws

Dinosaur claw bones tell about the lifestyle of their owners. Predatory dinosaurs tended to have very narrow, sharp, curved claws., like the talons on the foot of an eagle. They used their claws tike daggers,. to gain a secure hold and to stop their victims. from escaping. Plant-eating dinosaurs, by contrast, did not have sharp, talon-like claws. Their claws were short and hoof-like, such as an elephant's.