A recent paper in Science [Science 13 April 2007: Vol. 316. no. 5822, pp. 277 – 280] reports that fossil proteins have been found in a leg bone of a Tyrannosaurus rex. In fact, intact collagen proteins have been found in this 68 million-year old specimen. Most fossils of this age contain no soft tissue, since soft tissue would have long ago been replaced by minerals during the fossilization process. Further testing of the fossil protein reveals it is very similar to that found modern-day chickens. This is further evidence favoring the theory that birds are actually living descendants of dinosaurs. Interesting!
A readable account is at The Economist website.
