The climate data comes from the teeth of Egyptian mummies from various dynasties at the Musée des Confluences de Lyon in France. Led by graduate student Alexandra Touzeau,the researchers drilled small amounts of enamel off some of the teeth and tested it for oxygen and strontium isotopes.
The mummy’s teeth record the ratio of two oxygen isotopes (oxygen atoms with different numbers of neutrons) in their diet and their drinking water, which in this case is Nile River water, Lecuyer said. Shifts in the ratio of the isotopes indicate changing precipitation patterns in the region.
Story: Becky Oskin, LiveScience | Photo: Christophe Lecuyer