Figure 2
From: Heavy reliance on plants for Romanian cave bears evidenced by amino acid nitrogen isotope analysis
Isotope results for the cave bears investigated from the three cave sites in Romania. Scatterplots of: (a) δ13C and δ15N values of bulk collagen; (b) δ15N values of glutamate and phenylalanine. The solid lines indicate the theoretical lines for TP = 2 and TP = 3, respectively, in terrestrial C3-vascular-plant ecosystems. The spacing between these lines indicate the inter trophic enrichment (see Methods). Values for mammoth and cave bears from Belgium were taken from the literature57,58,60; (c) δ15N values of bulk bone collagen and phenylalanine; (d) δ15N values of bulk collagen and glutamate.
