Strontium content of fossil tooth enamel and diet of early hominids

Abstract

The level of the element strontium in fossil bone and teeth has been reported by several authors to be the same as the original amount physiologically present in the living animal from which the fossil derived. High strontium values are reportedly characteristic of herbivorous diet and low values of carnivorous diet. This paper reports a new nondestructive technique, using X-ray fluorescence and a vanadium shield with a 5-mm aperture for assessing strontium content in fossilized remains. Enamel specimens (N = 2,312) from 16 fossil vertebrate taxa from the Pliocene-Pleistocene Omo Beds were tested. Primary interest in this test case centered on determining the dietary preferences of Pliocene-Pleistocene Hominidae (sample size = 56). A pilot study on seven specimens seemed to confirm previous workers' results. A more rigorous test, however, showed no consistent correlation between strontium content and diets of fossil taxa. These results and theoretical considerations do not support the contention that strontium assay can be used as a paleontological tool to elucidate diet in fossil vertebrate taxa.