Calcium isotopes reveal the trophic position of extant and fossil elasmobranchs

Recent calcium isotope studies recovered a trophic level effect in marine ecosystems. However, elasmobranchs are virtually absent from such studies despite their important ecological role, their diversity and their extensive fossil record. Enameloid of extant elasmobranchs representing differing known ecologies were measured for δ44/42Ca. The results reveal that their calcium isotope values have a distribution (from − 0.27 to − 0.78‰) that...