Extended Data Fig. 7: LA-ICP-MS trace-element mapping of modern humans.
From: Elemental signatures of Australopithecus africanus teeth reveal seasonal dietary stress
The 7Li/43Ca, 88Sr/43Ca and 138Ba/43Ca ratios for each of three modern human specimens (Homo sapiens), labelled HT01 (upper first molar), HT02 (lower first molar) and HT03 (upper first molar) (left to right, respectively). The distribution pattern of all three elements is notably different to the signal observed in A. africanus, with enrichment towards the pulp cavity for both 88Sr/43Ca and 138Ba/43Ca that is probably associated with blood flow. An important difference is the absence of a repeated pattern that is observable for all three elemental ratios. Although some features could be interpreted as banding (such as the 88Sr/43Ca root signal of HT03), these isolated patterns are not mirrored in the distributions of the other elements.
