a, Location of the Saqqaq Culture site Qeqertasussuk, north-western Greenland (after ref. 15). b, Saqqaq hair sample. c, Saqqaq and modern hair shafts on a comparison microscope. d, Comparative cross-sections of modern Caucasian and Saqqaq hairs. e, Carbon and nitrogen isotope measurements on the Saqqaq hair (brown square, Qt 86 profile C 85/261:12 Oxford; pink triangle, Qt 86 profile C 85/261:12 Bradford), another Saqqaq hair sample from a similar context (green diamond, Qt 87 FB 20/20), six ancient Thule (Inuit) samples (purple circle), published data on modern Uummannaq (Greenland) omnivores (orange diamond), and modern Danish omnivores (blue square) and vegans (orange circle). Saqqaq and Thule are shown as averages of 2–3 replicates (Supplementary Information). Error bars, s.d. f, Calibrated ages (before present) on the Saqqaq hair and associated reindeer (Rangifer tarandus) bones, plotted using the INTCAL04 calibration curve40, are shown. The human hair dates are calibrated twice, one using a correction for the marine reservoir effect (Supplementary Information).