What if the asteroid had missed?

by: BBC News

The extinction of the dinosaurs was most probably caused by an asteroid hitting the Earth - but what would have happened if the giant space rock had missed?

For a long time it was thought that dinosaurs were a lumbering, cold-blooded extinction just waiting to happen. Even the word dinosaur has come to mean something that has outlived its time.

The scientific argument was that as cold-blooded creatures, dinosaurs would not have stood a chance of surviving an ice age.

"According to the first imaginings of palaeontologists and the general public about dinosaurs, we thought of them as reptiles," says Kristi Curry-Rogers, from the Science Museum of Minnesota.

"'Reptile' is a word which comes with a lot of other connotations, like cold-blooded, slow-moving, sprawling, scaly skins, kind of stupid."

But more recent discoveries, such as dinosaur fossils in both polar regions, reveal that these animals were far more adaptable than previously thought.

Dr Curry-Rogers has analysed fossilised bones from Late Cretaceous (65-99 million years ago) dinosaurs and found them to have more in common with mammals and birds than reptiles.

Something like us

Perhaps the most advanced dinosaur at the time of the extinction was the Troodon which was "as cunning as a fox", according to palaeontologist Larry Witmer of Ohio University.

They were small, upright, bi-pedal dinosaurs which lived in large groups. By studying the brain cavity, Witmer has found evidence they possessed good vision and even potentially had a brain structure compatible with problem-solving.

"If Troodon were around today, co-existing with humans, we'd probably call it a pest," says Professor Witmer.

http://news.bbc.co.uk/2/hi/6444811.stm