Washington, February 16 : An international team of researchers says that it has found evidence that Neanderthals moved from place to place during their lifetimes by studying a 40,000-year-old tooth with the help of laser technology.
Led by Professor Michael Richards of the Germany-based Max Planck Society and Durham University in the UK, the research team used laser technology to collect microscopic particles of enamel from the tooth.
The researchers examined the enamel for the isotope ratios of strontium, a naturally occurring metal ingested into the body through food and water. The process enabled them to uncover geological information showing where the Neanderthal had been living when the tooth was formed.
The tooth, a third molar, was formed when the Neanderthal was aged between seven and nine. It was recovered in a coastal limestone cave in Lakonis in Southern Greece during an excavation directed by Dr Eleni Panagopoulou of the Ephoreia of Paleoanthropology and Speleology (Greek Ministry of Culture).
However, the strontium isotope readings suggested that the enamel formed while the Neanderthal was living in a region made up of older volcanic bedrock.
"Strontium from ingested food and water is absorbed as if it was calcium in mammals during tooth formation. Our tests show that this individual must have lived in a different location when the crown of the tooth was formed than where the tooth was found," Professor Richards said.
"The evidence indicates that this Neanderthal moved over a relatively wide range of at least 20 kilometres or even further in their lifetime. Therefore we can say that Neanderthals did move over their lifetimes and were not confined to limited geographical areas," he added.
The research team believes that its findings, published in the Journal of Archaeological Science, may help answer a long-standing debate about the mobility of the now extinct Neanderthal species.
"Previous evidence for Neanderthal mobility comes from indirect sources such as stone tools or the presence of non-local artefacts such as sea shells at sites far away from the coast. None of these provide a direct measure of Neanderthal mobility," said Dr Katerina Harvati of the Max Planck Institute, in Germany, who initiated the study.
The researchers think that the laser ablation technique may also facilitate the measurement of other rare Neanderthal remains, which may be important to see how the result compares in other regions and at other time periods.
They say that the technique may also allow scientists to look at very small-scale migrations, which is not possible with traditional research methods. It may also be applied to research into early humans, they add.