Electron Probe Microanalysis of an early miocene shark tooth (Galeocerdo Aduncus) demonstrates that the zinc content was not diagenetically altered. Subsequent zinc isotope measurements in the tooth enameloid can be used to deduce a species’ trophic level. Such detailed elemental and isotopic study of diverse extant and extinct shark reveals dietary shifts throughout the Neogene time.
Recorded on a CAMECA SXFiveFE EPMA at Ruhr-Universität Bochum, Germany. Image courtesy of Niels Jöns.
Jeremy McCormack et al. (2022). Trophic position of Otodus megalodon and great white sharks through time revealed by zinc isotopes. Nature Communications 13:2980.