For the identification of insects and other fauna and flora of South Africa.

Friday, February 17, 2012

Dinosaur Park

Dinosaurs dominated life on earth for 150 million years. All dinosaurs lived on land, and had well developed hind legs.More than 350 different types of dinosaurs have already been identified, and many more will still be found. The biggest dinosaur is called Ultrasaurus, and was discovered in Mexico. It weighed in excess of 90 tones.
Although dinosaurs are classified as reptiles, many scientists believe that they were warm – blooded. If so, they would have been active, sociable and reasonably intelligent. Dinosaurs could move much faster than modern day reptiles. Some dinosaurs were always on the move, and must have had a fast metabolism.
The closest living animals to dinosaurs are birds. Small warm blooded dinosaurs 200 million years ago developed feathers to keep warm, and these creatures were the ancestors of birds. Like birds, dinosaurs laid eggs and had nests. Some even had communal nesting sites, and practiced parental care. Some dinosaurs had gizzard systems, like birds. Dinosaurs and birds have similar hollow bones and ankle joints
It is difficult to prove that dinosaurs had feathers, as feathers rearly fossilize, being soft tissue. Fortunately there is always a couple of exceptions to the rule, and distinctly feathered dinosaurs fossils have been found in Germany and more recently China.
Dinosaurs and crocodiles share common ancestors, and are thus related. BUT dinosaurs developed dramatically over time, crocodiles did not change much. They are perfectly adapted to survive, and can go for up to two years without having to eat at all.
They have a normal pulse rate of 23 to 24 beats a minute, And when it becomes very cold, the pulse can drop to between 2 and 3 beats a minute. Crocodiles did not become extinct when the dinosaurs died out. Dinosaurs died out 65 million years ago.

A huge meteorite smashed into the earth , resulting in a massive explosion, hurtling clouds of dust, smoke and watervapour into the atmosphere. These clouds obscured the sun, and the earth cooled rapidly. Plants died. Leading to the death of first plant eating and then meat eating dinosaurs. A huge crater has been found just off the coast of Mexico, positive proof of a major impact. Some smaller animals survived this ordeal, and as the sun set on the dinosaurs, it dawned on the age of mammals.
There were mammals during the time of dinosaurs, but they were small, inconspicuous, hiding from dinosaurs at all times. When dinosaurs became extinct, the mammals managed to survive. They can keep warm, as they have fur on their bodies. They are small, and don’t need much food.
Smaller mammals tend to store up food for hard times, and they have warm burrows in which to ward off the intense cold that killed the dinosaurs. The mammals went on to become the dominant animals on land. During the millions of years that have passed since the death of dinosaurs and before man, many different mammal species have come and gone.