Tuesday, February 24, 2009

Interesting science facts - Dinosaurs

Dinosaurs were dominant creatures on Earth fore more than 160 million years (230 million years ago to 65 millions years ago).

Dinosaur is term coined from two Greek words, deinos meaning terrifying, and sauros meaning lizard. The term was coined by Sir Richard Owen, back in 1842.

The first dinosaur fossils were discovered in the beginning of the 19th century.

At the end of year 2008 there was 1047 different dinosaur species that have been named.

The longest complete dinosaur skeleton is the 27 m (89 ft) long Diplodocus, which was discovered in Wyoming in the United States and displayed in Pittsburgh's Carnegie Natural History Museum in 1907.

The smallest dinosaurs were roughly the same size as today's pigeons.

The biggest dinosaurs that once inhabited our planet were heavier than 120,000 kg (260,000 lb).

Many scientists agree that the asteroid collision theory is responsible for mass extinction of dinosaurs. According to this theory when an asteroid struck the Earth 65 million years ago, the resulting heat pulse wiped out in very short time all dinosaurs on the planet.

All dinosaurs lived on land as they were all land animals. Many people think wrong by putting flying pterosaurs or the swimming ichthyosaurs into dinosaurs category but they though closely related to dinosaurs are no dinosaurs.

Dinosaurs dominated our planet for 165 millions years, humans for instance have only been on our planet for about one million of years.

The biggest dinosaurs were the biggest land animals in history of our planet but not the biggest animals on Earth because for instance blue whales are much bigger than any known dinosaur species.

The infamous Tyrannosaurus rex was 40 feet (12.4 m) long, 15 to 20 feet (4.6 to 6 m) tall and weighing from 5 to 7 tons. First T-rex fossils were found by Barnum Brown in 1902.

Stegosaurus was big herbivore weighing about 6,800 pounds (3100 kg).

Triceratops was also herbivore. Triceratops in fact means "three horned face". Triceratops relied on their horns and quick charge when facing an enemy.

Not all dinosaurs lived in the same time, which is really no surprise when you look at their 160 million years long dominance on our planet. For instance Tyrannosaurus only appeared 80 million years ago after the extinction of stegosaurus.

Many dinosaur experts will tell you that diamonds are not extinct because birds are also dinosaurs based on features of their skeleton. The popular categorization is the one that describes extinct dinosaurs as "non-avian dinosaurs" and birds as "avian dinosaurs."

Most movies about dinosaurs are far from true. If you for instance look at Jurassic part you have T Rex that runs 50 mph, and the fastest dinosaurs could achieve speed of only 27 mph. And in most these movies dinosaurs are described much smarter than they actually are (their hunting technique, determination, etc.).

It is still very difficult for scientists to figure out how the dinosaurs sounded, how they behaved, how they mated, what color they were, or even how to tell whether a fossilized remains belong to male or female dinosaur.

Some dinosaurs has ability to walk either on two legs, or on four legs though majority walked either on two legs or on four legs.

The oldest known dinosaur is called Eoraptor; this dinosaur was meat-eater and lived about 228 million years ago.