For many years, it was widely believed that fossils no longer contained any original organic molecules as the fossilization process was thought to destroy them.
Now, a groundbreaking study, led by the University of Liverpool, has revealed strong evidence that Mesozoic fossils still preserve their original organic materials.
Using advanced mass spectrometry and other techniques, researchers identified preserved collagen remnants in the hip bone of an Edmontosaurus, a duck-billed dinosaur, helping to resolve a debate that has spanned three decades.
The study, published in the journal Analytical Chemistry, used several techniques, including protein sequencing, to detect and characterize bone collagen in the 22-kilogram fossil.
The fossil is an exceptionally well preserved Edmontosaurus sacrum excavated from Upper Cretaceous strata of the South Dakota Hell Creek Formation. It is part of the University of Liverpool's collections, offered a unique opportunity for cutting-edge analyses.
Key Findings and implications
Professor Steve Taylor, chair of the Mass Spectrometry Research Group at the University of Liverpool's Department of Electrical Engineering & Electronics, said: "This research shows beyond doubt that organic biomolecules, such as proteins like collagen, appear to be present in some fossils.
"Our results have far-reaching implications. Firstly, it refutes the hypothesis that any organics found in fossils must result from contamination.
"Secondly, it suggests that cross-polarized light microscopy images of fossil bones, collected for a century, should be revisited. These images may reveal intact patches of bone collagen, potentially offering a ready-made trove of fossil candidates for further protein analysis. This could unlock new insights into dinosaurs- for example revealing connections between dinosaur species that remain unknown.
"Lastly, the findings inform the intriguing mystery of how these proteins have managed to persist in fossils for so long."
The study not only appears to resolve a long-standing scientific debate but also opens further avenues for studying ancient life, offering a glimpse into the biochemical preservation of fossils of extinct creatures.
Collaboration across disciplines
Researchers from UCLA contributed to the study, using tandem mass spectrometry to detect and quantify-for the first time-the amino acid hydroxyproline, which is specific to collagen when found in bone, thus confirming the presence of decayed collagen.
Additional sequencing and imaging techniques using facilities at the University's Materials Innovation Factory and the Centre for Proteome Research provided strong evidence of original protein within the fossil.
The study brought together experts from multiple disciplines:
- Researchers from the University of Liverpool's Mass Spectrometry Research Group conducted protein sequencing and mass spectrometry tests.
- Specialists from the University of Liverpool's Materials Innovation Factory carried out additional analyses to confirm the results.
- The Centre for Proteome Research at the University of Liverpool identified fragments of collagen alpha-1, the main form of collagen in bone tissue.
- Collaborators at UCLA contributed with advanced tandem mass spectrometry to detect and quantify key amino acids.
The paper 'Evidence for Endogenous Collagen in Edmontosaurus Fossil Bone (doi: 10.1021/acs.analchem.4c03115) is published in the journal Analytical Chemistry.
