Researchers have found what they believed are the remains of ancient blood cells and collagen fibers within a dinosaur bone.
The 75 million-year-old bone fragment is poorly preserved, which is surprising because in the past only exceptionally well-preserved bone fossils have been found to contain detectable soft tissue, Imperial College London reported.
In the recent study, the researchers looked at eight fossil fragments, and found part of a fossilized dinosaur claw contained tiny structures that appeared to be "ovoid and with an inner denser core." They believe these structures could be red blood cells, but further research is needed to confirm this.
"We still need to do more research to confirm what it is that we are imaging in these dinosaur bone fragments, but the ancient tissue structures we have [analyzed] have some similarities to red blood cells and collagen [fibers]. If we can confirm that our initial observations are correct, then this could yield fresh insights into how these creatures once lived and evolved," said study author Sergio Bertazzo, a Junior Research Fellow from the Department of Materials at Imperial College London.
In another bone fragment the researchers also noticed that looked fibrous, and a banded structure similar to what is seen in collagen fibers today. These structures are varied among species in the animal kingdom, creating a type of "fingerprint." If verified, this ancient collagen could be used to gain insight into how groups of dinosaurs are related to each other.
To make their findings, the researchers combined a number of technologies including: scanning electron microscopy to observe the composition of the tissue; ion beams to slice into the samples and observe their interior; and a transmission electron microscope to detect the fibrous structures.
The findings shows the ancient tissue had some similarities with what was seen in blood samples taken from modern day Emu. In the future, the researchers plan to look for these revealing structures in additional fossil samples.
"Our study is helping us to see that preserved soft tissue may be more widespread in dinosaur fossils than we originally thought. Although remnants of soft tissues have previously been discovered in rare, exceptionally preserved fossils, what is particularly exciting about our study is that we have discovered structures reminiscent of blood cells and collagen [fibers] in scrappy, poorly preserved fossils. This suggests that this sort of soft tissue preservation might be widespread in fossils. Early indications suggest that these poorly preserved fossils may be useful pieces in the dinosaur jigsaw puzzle to help us to understand in more detail how dinosaurs evolved into being warm blooded creatures, and how different dinosaur species were related," said study author Susannah Maidment, a Junior Research Fellow from the Department of Earth Science and Engineering at Imperial College London
The fingings were published in a recent edition of the journal Nature Communications.
