Fossilisation of organic material was long thought to result in the complete loss of original content. However in the last 20 years, several high-profile publications reported the discovery of proteins, blood vessels, blood cells and even DNA. But for as long as these arguments have existed, so too has a counterargument as to the validity of the discoveries. In this episode, we're joined by Dr Evan Saitta of the Field Museum of Natural History, Chicago, lead author of a recent paper seeking to discover and evaluate the preservation of putative original organic materials within dinosaur bones.