Some 3 million years ago, a small mouse with a reddish coat scratched its back and a white belly across the landscape of what is now Germany. We know this thanks to a remarkable new breakthrough in which reddish dye was discovered in an old fossil scientific science first.
Fossils with soft tissue spores are exceptionally rare, making it difficult ̵
New research published Tuesday in Nature Communications describes a new technique where scientists were able for the first time to detect reddish dye in a 3 million year old mouse fossil. Using X-ray spectrography, chemical imaging and other techniques, researchers from the University of Manchester and several other institutions showed that the extinct field mouse had reddish to brown fur on its back and a white stomach. Excitingly, the new technique could be used to detect reddish color on other fossils that retain traces of soft tissue.
"The fossils we have studied have the great potential to unlock many secrets of the original organism. We can reconstruct key facets of life, death, and the subsequent events that affect preservation before and after the funeral," Phil Manning, senior paleontologist on paper and a professor at UM, in a press release. "To unpick this complicated fossil chemical archive, an interdisciplinary team requires combining their efforts to crack this problem."
The new study actually required physicians, paleontology and chemistry experts according to Manning. One important challenge was to develop a new technique for discerning red color pigments in an old fossil. To do this, the researchers had to map the chemical elements associated with the pigment melanin – the predominant pigment in animals. For the color red, the version of melanin is pheomelanin, and for the variety it is eumelanin. In fossils, the red pigment is rarer and harder to detect, as it is less stable over large time scales.
Prior to the new study, researchers had already developed a technique for detecting eumelanin in old fossils. This was done to show that archeopteryx, an early bird-like dinosaur, had black feathers. Similarly, paleontologists from Bristol University used a similar method to show that some dinosaurs had lighter coloring on their undersides and darker staining on the top – a form of camouflage known as a shade.
Three years ago, Nick Edwards, co-author of the new study and a scientist at the SLAC National Accelerator Laboratory, showed that it was possible to distinguish eumelanin pigments from pheomelanin pigments in modern birds, a discovery that established an important foundation for the new study. .
"We had to build a strong foundation with modern animal tissues before we could apply the technique to these ancient animals," Edwards said in a SLAC statement. "It was really a tip site using chemical signatures to crack the staining of old animals with soft tissue fossils."
For the new analysis, the researchers used an extraordinary 3 million year old fossil of an extinct field mouse found near the German village of Willershausen. The fossil called "mighty mouse" was blown by X-ray at Stanford Synchrotron Radiation Lightsource and at Diamond Light Source in the UK. This allowed the researchers to study interactions of X-rays with the fossil chemistry. The trick was to see the trace metals that were once present in the soft tissues of the living organisms.
"Once we simply saw minerals, we gently remove the" biochemical ghosts "of long extinct species," Manning said.
Observations showed that the trace metals in the fossil bind to the organic chemicals in the same way as in living creatures with high concentrations of red pigment in their tissues. This resulted in the identification of pheomelanin in the fossilized mouse skin.
"Finding foreclosure in a 3 million-year-old mouse is neat and shows how modern analytical techniques can reveal important information that traditional investigation methods would probably have missed," Michael Pittman, a paleontologist at Hong Kong University who was not involved in the new study, Gizmodo told.
Pittman said his own work on developing laser-stimulated fluorescence imaging is similar in this regard, as he used to reveal the first example of dinosaur shielding.
Exciting is this new, non-destructive technique that could be used to study other fossils.
"The resolution of pheomelanin pigment residue must now be possible through a combination of chemical imaging and X-ray spectroscopy, at least for samples with an age equal to or less than 3 million years", the authors wrote in the new study.
Hopefully, these future efforts will continue to add color to what was once a monochrome past.