Abstract
The recent findings of bio-molecules, soft-tissue blood vessels and blood cells in 65-million-year-old Tyrannosaurus rex fossil bones have caused geologists to re-evaluate the process of the preservation of fossils. After all, everyone knows that a fossil is an impression, cast, outline, or track of any animal or plant that is preserved in rock after the original organic material is transformed or removed. So, how can blood vessels and biomolecules be found in fossils that are rock? Answer: a fossil does not need to be turned to stone to be a fossil.