What did Neanderthals eat? Were they carnivorous, or did they also chow down on vegetables and mushrooms?
To determine an individual's position in the food chain, scientists have usually had to extract proteins and analyse the nitrogen isotopes present in the bone collagen.
This method can often only be used in temperate environments, and is less useful on samples over 50,000 years old.
When these conditions are not met, nitrogen isotope analysis is very complex, or even impossible.
This was the case for the molar from the Gabasa site analysed in this study.
Klevia Jaouen, a CNRS researcher, and her colleagues decided to analyse the zinc isotope ratios present in the tooth enamel, a mineral that is resistant to all forms of degradation.
This is the first time this method has been used to attempt to identify a Neanderthal's diet.
The lower the proportions of zinc isotopes in the bones, the more likely they are to belong to a carnivore.
The analysis was also carried out on the bones of animals from the same time period and geographical area, including carnivores such as lynxes and wolves, and herbivores like rabbits and chamois.
The results showed that the Neanderthal to whom this tooth from the Gabasa site belonged was probably a carnivore who did not consume the blood of their prey.
Broken bones found at the site, together with isotopic data, indicate that this individual also ate the bone marrow of their prey, without consuming the bones, while other chemical tracers show that they were weaned before the age of two.
Analyses also show that this Neanderthal probably died in the same place they had lived in as a child.
Compared to previous techniques, this new zinc isotope analysis method makes it easier to distinguish between omnivores and carnivores.
To confirm their conclusions, the scientists hope to repeat the experiment on individuals from other sites, especially from the Payre site in south-east France, where new research is underway.
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