What if the asteroid had missed ?

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. The evidence points to them being fast-growing and, crucially, that at least some of them were warm-blooded to some degree.

"They were perfectly well-adapted to deal with the problems of maintaining a body temperature," Dr Curry-Rogers told the BBC's Horizon programme. In other words, some of the dinosaurs were more than equipped to survive almost anything that the evolving planet had to throw at them. "They were the superlatives; they were the biggest, the heaviest, the meanest, the longest. You name it, dinosaurs were it," says fellow palaeontologist Phil Currie, from the University of Alberta in Canada, who has access to one of the richest areas of dinosaur research in the world.

View: Full Article | Source: BBC News