Date:

Iron preserves, hides ancient tissues in fossilized remains

New research from North Carolina State University shows that iron may play a role in preserving ancient tissues within dinosaur fossils, but also may hide them from detection. The finding could open the door to the recovery of more ancient tissues from within fossils.

Mary Schweitzer, an NC State paleontologist with a joint appointment at the N. C. Museum of Natural Sciences, first announced the surprising preservation of soft tissues in a T. rex fossil in 2005. Her subsequent work identified proteins in the soft tissue that seemed to confirm that the tissue was indeed T. rex tissue that had been preserved for millions of years. But the findings remained controversial in part because no one understood the chemical processes behind such preservation.

- Advertisement -

Schweitzer’s latest research shows that the presence of hemoglobin – the iron-containing molecule that transports oxygen in red blood cells – may be the key to both preserving and concealing original ancient proteins within fossils. Her results appear in Proceedings of the Royal Society B.

“Iron is necessary for survival, but it’s also highly reactive and destructive in living tissues, which is why our bodies have proteins that transport iron molecules to where they are needed but protect us from unwanted reactions at the same time,” Schweitzer says. “When we die, that protective mechanism breaks down and the iron is turned loose on our tissues – and that destructive process can act in much the same way formaldehyde does to preserve the tissues and proteins.”

Hemoglobin seems to be the key. Both birds and crocodiles, the dinosaur’s closest living relatives, have large, nucleated red blood cells. Therefore they also have more hemoglobin per cell than mammals. If dinosaur blood cells were similar to either one of those species, which seems likely, then their blood cells would also contain much more hemoglobin than human cells, amplifying iron’s preservative effect on the tissues. If the hemoglobin were contained in a bone in a sandstone environment, keeping it dry and insulated from microbes, preservation becomes more likely.

Schweitzer and her team noticed that iron particles are intimately associated with the soft tissues preserved in dinosaurs. But when they chelated – or removed the iron from – soft tissues taken from a T. rex and aBrachyolophosaurus, the chelated tissues reacted much more strongly to antibodies that detect the presence of protein, suggesting that the iron may be masking their presence in these preserved tissues. They then tested the preservation hypothesis by using blood vessels and cells taken from modern ostrich bone. They soaked some of these vessels in hemoglobin taken from red blood cells, while placing other vessels in water. Two years later, the hemoglobin-treated soft vessels remained intact, while those soaked in water degraded in less than a week.

- Advertisement -

“We know that iron is always present in large quantities when we find well-preserved fossils, and we have found original vascular tissues within the bones of these animals, which would be a very hemoglobin-rich environment after they died,” Schweitzer says. “We also know that iron hinders just about every technique we have to detect proteins. So iron looks like it may be both the mechanism for preservation and the reason why we’ve had problems finding and analyzing proteins that are preserved.”

Header Image : Albertosaurus : Wiki Commons

Contributing Source : North Carolina State University

- Advertisement -
spot_img
Mark Milligan
Mark Milligan
Mark Milligan is multi-award-winning journalist and the Managing Editor at HeritageDaily. His background is in archaeology and computer science, having written over 7,500 articles across several online publications. Mark is a member of the Association of British Science Writers (ABSW), the World Federation of Science Journalists, and in 2023 was the recipient of the British Citizen Award for Education, the BCA Medal of Honour, and the UK Prime Minister's Points of Light Award.
spot_img

Mobile Application

spot_img

Related Articles

Bronze fitting depicting Alexander the Great found on Danish Island

Archaeologists have discovered a bronze fitting depicting Alexander the Great on the Danish island of Zealand.

Archaeologists uncover exquisite Roman glassware in Nîmes

An exquisite collection of glassware dating from the Roman period has been uncovered by INRAP archaeologists in the French city of Nîmes.

Frescos discovery among the finest uncovered at Roman Pompeii

A collection of frescos recently discovered at the Roman city of Pompeii have been described as among the finest found by archaeologists.

Study suggests that Egyptian sky-goddess symbolises the Milky Way

In Ancient Egyptian religion, Nut was the celestial goddess of the sky, stars, the cosmos, astronomy, and the universe in its whole.

Traces of Kettering’s wartime history rediscovered

Researchers from the Sywell Aviation Museum have announced the rediscovery of a preserved WW2 air raid shelter in Kettering, England.

Earthen pot containing 3,730 lead coins found at Phanigiri

Archaeologists from the Department of Archaeology have discovered an earthen pot containing a hoard of 3,730 lead coins at the Buddhist site of Phanigiri, located in Suryapet district, India.

Bronze lamp revealed as cult object associated with Dionysus

A study of a bronze lamp found near the town of Cortona, Italy, has revealed that it was an object associated with the mystery cult of Dionysus.

Neolithic coastal settlements were resilient in the face of climate change

A study of the submerged site of Habonim North indicates that Neolithic coastal settlements were resilient in the face of climate change.