The word dinosaur means ‘terrible lizard’ in Greek, however dinosaurs are closer relatives of the bird than the lizard. Dinosaurs belong to the family Dinosaurian, which went extinct about 66 million years ago. Based on fossil records it is believed dinosaurs roamed the earth for 135 million years before they died out.
Today, there are approximately 700 known species of dinosaur and 300 valid genera. It is estimated that there still remains 700 to 900 more dinosaur genera to be discovered and named. This comes as no surprise seeing as this number is miniscule compared to species of birds, mammals and reptiles that exist today.
Perhaps the most well known dinosaur, the Tyrannosaurus Rex (T-Rex), was once the largest land predator, making it a fearsome creature. Weighting in at 10 tons and standing up to 12 metres tall, the T-Rex was likely an apex predator of its time.
However, not all dinosaurs were fearsome. Although the Sauropods were the largest land animal to have lived, they were slow and herbivorous. A Sauropods neck could reach lengths of 15 metres, allowing them to feed on vegetation high up in the trees.
Today, we know of many animals that closely resemble their dinosaur ancestors. These include the saltwater crocodile, monitor lizards and even the cassowary, just to name a few. Birds are classified as modern feathered dinosaurs, making them the only group to have survived extinction millions of years ago.
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