Fig. 2: Range of δ13C, δ15N and δ66Zn values for P. hispida and U. maritimus bones.

Range of δ13C (a), δ15N (b) and δ66Zn (c) values for P. hispida and U. maritimus bones for all locations. Site names are colour coded following Fig. 1. Dashed lines represent mean values when including all sites. We included already published δ15N and δ13C values from sites RbJu-1, PaJs-13, QkHn-13, KTZ and QjJx-1 sites4,15,30,31 and already published δ66Zn values from QjJx-115. Error bars represent the measurement uncertainty.