If scientists are able to extract aor a from a fossil, it is even better! But extremely rare. Indeed, the organic parts of an animal in the process of fossilization can survive thousands of years – and no more – before being replaced by minerals.
In 2007, American scientists were understandably stunned when they discovered an almost intactin the fossilized bones of a 68 million year old Tyrannosaurus! The had been buried deep down in a bone and miraculously protected from mineralization. But which one was it?
Having extracted thefrom bone, the paleontologists assumed that it was most probably collagen – one of the major components of bone. The was determined in the laboratory and then compared with millions of others stored in , using tools. The scientists were thus able to prove their initial hypothesis: the Tyrannosaurus was indeed collagen.
Finding collagen in a bone – even from Tyrannosaurus – is not surprising. However, scientists now have 68 million year old collagen that they can compare with the collagen of thousands of other living species. Why would they do this? To find out how Tyrannosaurus – and dinosaurs as a whole – are related to other species.
Tyrannosaurus collagen is very similar to a chicken’s! So do birds and Tyrannosaurus belong to the same family? In truth, scientists had already made that assumption following anatomical comparisons. Today, they have genetic confirmation of their hypothesis.