A Neanderthal premolar tooth (IMAGE) University of Southampton Caption A Neanderthal premolar tooth from the Almonda cave system, Portugal, seen from different angles. Isotopes of strontium were used to track the movement of this individual over the 2 to 3 years the enamel took to form. Credit João Zilhão Usage Restrictions Use of credit required. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.