Neanderthal fossils discovered in a cave in Belgium are much older than previously thought. In fact, they are thousands of years older, so Neanderthals were in Europe much longer than scientists thought. This is what concludes a study published in the Proceedings of the National Academy of Sciences of the United States of America. The research was also carried out by a team from Belgium, Great Britain and Germany.
Earlier dating of the fossils concluded that Neanderthals had been in Europe approximately 24,000 years ago. However, new evidence confirms that this species was in Europe between 44,000 and 40,000 years earlier. Having a more accurate idea of when our closest relatives disappeared is a first step to better understand their nature and capabilities, as well as to discover why they ended up becoming extinct.
Radiocarbon dating
As co-lead author of the research, Thibaut Deviese, from the University of Oxford and the University of Aix-Marseille says, scientists have developed a more effective method of preparing samples that could better remove contaminants. This method is based on radiocarbon dating, although they have refined the way they collect samples.
All living things absorb carbon from the atmosphere (including -14 carbon that is assimilated from carbon dioxide). When plants and animals die, they stop exchanging carbon with the biosphere and their carbon -14 content begins to decrease due to the law of radioactive decay. For this reason, the amount of carbon -14 that remains in their remains when they are dated allows us to determine how many years they lived.
The researchers also established the age of two specimens from two other Belgian areas (Fonds de Foret and Engis) where they found similar ages . Also, thanks to genetic sequencing, the researchers were able to show that a Neanderthal shoulder bone (which had been dated 28,000 years ago) was actually heavily contaminated with bovine DNA.
Thus, two centuries after the discovery of the Neanderthal boy of Engis, scientists have been able to specify a reliable age. This is crucial in archeology, since without a chronological framework it is impossible to understand the relationship between Homo neanderthalensis and Homo sapiens, as claimed by Tom Higham, a researcher at the University of Oxford.