A false-color image of a dinosaur fossil, taken with a scanning electron microscope, shows linear features that look like collagen fibers.


Sergio Bertazzo

Signs of ancient cells and proteins found in dinosaur fossils

The cupboards of the Natural History Museum in London hold spectacular dinosaur fossils, from 10-centimeter, serrated Tyrannosaurus rex teeth to a 4-meter-long hadrosaur tail. Now, researchers are reporting another spectacular find, buried in eight nondescript fossils from the same collection: what appear to be ancient red blood cells and fibers of ancient protein.

Using new methods to peer deep inside fossils, the study in this week’s issue of Nature Communications backs up previous, controversial reports of such structures in dinosaur bones. It also suggests that soft tissue preservation may be more common than anyone had guessed. “It’s encouraging,” especially because the proteins were found in what appear to be the most unremarkable, ordinary bones, says Matthew Collins, an archaeologist and biochemist at the University of York in the United Kingdom. But he and others caution that the team hasn’t proven beyond doubt that the structures do contain ancient proteins.




The U.K. team tested more fossils and ran microscopic samples from what appear to be collagen fibers through a mass spectrometer to get the weight of the component molecules. The weights came back as identical to those of the three most common amino acids in collagen, the team reports.

But outsiders, including Schweitzer, say that the weights aren’t conclusive proof that the molecules being analyzed are amino acids, or that they came from a dinosaur rather than a contaminant. A different type of mass spectrometer that can provide the sequence of the amino acids in a protein fragment would strongly suggest the existence of collagen and replicate the earlier work, Collins says. Maidment says the team hopes to do such studies soon. If they succeed, the work may spur additional efforts to isolate dinosaur proteins and understand how they differed from those of their modern relatives.