Fig. 2.

MALDI mass spectra of tryptic digests of bone protein extracts from Neanderthals Shanidar 2 (a) and Shanidar 6 (b). Insets show the expanded regions of the spectra. Only the ion with m/z 2,822.2 from the Shanidar 2 sample was intense enough to perform CID MS, but peaks observed in a MALDI spectrum of a modern human bone protein digest corresponding to osteocalcin tryptic fragments were observed in both Shanidar 2 (m/z 2,822.2, 20–43; m/z 2,978.6, 20–44) and Shanidar 6 (m/z 2,274.8, 1–19; m/z 2,978.8, 20–44) sample spectra.