This is a hybrid event. Please contact the organizer for the Zoom link. We ask that you log in to Zoom with your full, real name.
Sr and O isotopes reveal fossil shark teeth in Iron Age strata and seabream trade from Egypt to Israel
Combined Sr and O isotope analyses can serve as a powerful tool for assessing fish provenance and even for identifying fossil fish teeth in archeological contexts. For this purpose, we established a reference Sr and O isotope dataset of extant fish teeth from major water bodies in the Southern Levant. Fossil shark teeth were identified within Iron Age cultural layers (8–9th century BCE) in the City of David, Jerusalem. Their enameloid Sr and O isotope compositions are both much lower than values typical for modern Mediterranean fish. Sr isotope stratigraphy places these fossil shark teeth into the Late Cretaceous (~80.3 ± 3.2 Ma). This is further supported by their taxonomy, the high dentine apatite crystallinity, low organic C, high U and Nd contents, characteristics that are typical for fossils, and different from those of archaeological seabream teeth from the same cultural layers. Iron Age seabream enameloid has still modern seawater-like 87 Sr/ 86 Sr. However, elevated δ18O values of seabream teeth point to a hypersaline seawater habitat, indicating that these seabreams were probably exported from the hypersaline Bardawil Lagoon in Sinai (Egypt) to the Southern Levant since the Iron Age period, possibly even earlier.
Thomas is a professor of paleontology at the University of Mainz. He develops and applies geochemical methods in fossil bones and teeth to reconstruct the biology, diet and ecology of extinct vertebrates as well as their fossilisation processes. Combining isotope and dental wear analysis on teeth, Thomas and his lab develop a toolbox for diet reconstruction in paleontology and archeology. Currently they are assessing the diet of mammal-like reptiles and dinosaurs to determine the evolution of plant-feeding among land vertebrates.