DNA acts as a life’s information molecule. Have you ever wondered how long the biological information can survive in a DNA?
In a new study, an international team of researchers reveals a well preserved 75 million year old dinosaur fossils containing outlines of cells and structures formed from the dinosaurs’ original DNA.
The study, published last week takes a close look at two juvenile skull bones from the hadrosaur Hypacrosaurus stebingeri, a plant-eating dinosaur that lived about 75 million years ago.
Inside the tiny fossils, researchers can see what appear to be cells, some frozen in the process of dividing. Others contain darkened balls that look just like nuclei, the cellular structures that store DNA. And one cell even seems to contain dark, tangled coils that resemble chromosomes, the condensed strands of proteins and DNA that form during cell division.
“It’s a sub cellular level of preservation that’s never been reported before in a vertebrate,” says a researcher.
To test the fossilized material, the researchers applied stains that bind to DNA in living cells to the bits of dinosaur skull. These stains stuck to particular spots within the fossil cells, making them glow in fluorescent red and blue. As far as the researchers can tell, whatever the stains are binding to, are derived from the dinosaur’s original molecules, not an outside contaminant such as bacteria.
The study serves as a reminder that fossils can preserve microscopic structures and even traces of the molecules that made up an organism’s cells, from pigments to proteins and more.