Dinosaurs

Dinosaur

Literally dinosaur translates as ‘terrible or wondrous lizard’. They were given their name by the English paleontologist Richard Owen in 1841.

These fascinating creatures inhabited the Earth for more than 160 million years! The dinosaur era starts 230 million years ago and ends 65 million years ago. Why nearly all dinosaurs were extinct is still a mystery, yet to be solved.

In fact, the dinosaurs aren’t really completely extinct. Did you know, scientist think that about 10’000 living bird species are descendant of the old dinosaurs and so are classified as dinosaurs?

Apart from all the birds, there has been around 700 different dinosaur types found and identified.

Dinosaurs came in all sorts of sizes:

• Largest dinosaur is thought to be Sauroposeidon who stood 18 metres (60 feet) and weighted 60 tonnes.
• Smallest known dinosaur is Hesperonychus, who stood only 50 cm (1 feet 8 in) and waighted 2 kg (4lb 6oz)

Dinosaurs are found on all continents, but that does not mean they could swim across the seas and oceans. It is so, because at the time dinosaurs lived, all the continents were not separated. It took around 50 million years before they started to drift from each other.

Dinosaurs are found the period of Earth’s history known as the Mesozoic Era, which began 250 million years ago and ended 65 million years ago. The Mesozoic is further subdivided into three periods, the Triassic, Jurassic, and Cretaceous. Fossils show that the dinosaurs originated during the mid to Late Triassic, perhaps 230-235 million years ago, until they died out at the end of the Cretaceous.

No-one can say for sure, how did dinosaurs look like, but there are some lines of evidence in the fossil record, and from studies of modern animals. Dinosaur fossils have been known about for millennia, though their true nature was not recognized. The Chinese considered them to be dragon bones, while Europeans believed them to be the remains of giants and other creatures killed by the Great Flood.

As mentioned above, there is still mystery how the dinosaurs disappeared. There are some theories:

• Extreme volcanic activity and the additional acid rain.
• Changes in the Earth’s orbit that might have caused climactic cooling.
• Large amounts of methane changing the Earth’s atmosphere (causing a greenhouse effect).
• A nearby supernova (an exploding star) could have bathed the Earth in deadly radiation.