Summary
8 October 2010
Scientists have found dinosaur-like footprints in a 250-million-year-old rock, suggesting that first dinosaur-like creatures emerged up to nine million years earlier than previously thought.
Reporter
Pallab Ghosh
Image by Grzegorz Niedzwiedzki
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These earliest dinosaur-like animals were about the size of domestic cats. They would have weighed two or three pounds (1 to 1.5 kilos) and walked on four legs.
But what's really intrigued scientists is that they date from two million years after the worst mass extinction event in the history of the planet.
It was a time when volcanic eruptions, sudden global warming and a stagnation of the oceans wiped out more than 90% of all life on Earth.
Up until recently scientists thought that dinosaurs emerged 15 to 20 million years after this event. But the new footprints suggest that they arose directly as a result of the devastation, filling a gaping ecological void. Without the mass extinctions there would have been no dinosaurs.
Pallab Ghosh, 大象传媒 News, London
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Vocabulary
- dinosaur
large reptile that lived around 200 million years ago
- mass extinction
large number of deaths in a relatively short period of time
- volcanic eruptions
explosions of ash, fire and liquid rock coming out of the earth
- global warming
increased average temperatures across the world
- stagnation
inactivity
- wiped out
completely destroyed
- devastation
destruction
- gaping
very wide
- ecological
connected with plants, animals and the environment
- void
area of empty space
