Researchers say they have discovered traces of DNA in the fossil remains of a sea turtle dating back six million years that closely resemble the species of Kemp’s sea turtle and the olive sea turtle.
This is one of the rare times that genetic material is found in fossils of a vertebrate this old.
The researchers stated that some bone cells were preserved in a very precise way in the fossil that was extracted from the ground in an area located on the coast of Panama overlooking the Caribbean Sea.
The fossil is incomplete. While the turtle’s shell is almost complete, the rest of the skeleton is incomplete.
The researchers who prepared the study published in the scientific journal “Journal of Vertical Paleontology” added that the turtle may have reached a length of 30 centimeters during its life.
Paleobiologist Edwin Cadena reported that in some bone cells, the nuclei were preserved and interacted with a chemical solution that allowed researchers to monitor the presence of DNA residue, which is the molecule that carries the genetic data necessary for the development of living organisms and performing their functions.
Cadena added, “I want to point out that we did not extract DNA, but rather we were only able to detect the presence of traces of DNA in the nuclei.”
The oldest genus of sea turtles
• According to Cadena, the only two fossils of vertebrates older than this turtle that contain traces of similar DNA belong to two dinosaurs: Tyrannosaurus, which lived 66 million years ago, and Brachylephasaurus, which lived 78 million years ago.
• Cadena stated that traces of DNA have also been found in insects dating back tens of millions of years.
• The researchers indicated that the fossil represents the oldest known species of the sea turtle genus and contributes to shedding light on the incompletely understood evolutionary history of this genus.
• Cadena believes that “every fossil and every fossil site has certain conditions that, in some cases, favor the preservation of remains of original biomolecules such as proteins and DNA.”
• Cadena concluded his talk about the discovery by saying: “In the future, with more studies of this type, we may at some point be able to create a sequence of very small pieces of DNA and infer things about their relatives of the same sex or include that information in a broader study of the evolution of molecules”.
