Table 2.
XRF point analyses and melanin concentrations (units ppmW except where otherwise indicateda)
| H. sapiens | A. sylvaticus | M. musculus | A. atavus | A. atavus | |||||
|---|---|---|---|---|---|---|---|---|---|
| Brown | Blonde | Red | Dark red | White | Dark gray | Albino | Dorsal fossil | Lateral fossil | |
| Ca | 843 (34) | 994 | 387 | 2163 | 1530 | 961 | 297 | b | b |
| Ti | 4 (1) | 25 | bld | 14 | 7 | 4 | 1883 | 1768 | |
| V | 1.0 (4) | 0.5 | 2 | 3 | 1 | 2 | 400.5 | 564 | |
| Mn | 2.0 (8) | 2 | 0 | 3 | 1 | 1 | b | b | |
| Fe | 36 (5) | 145 | 10 | 417 | 207 | 61 | b | b | |
| Ni | 10 (3) | 4 | 1 | bld | bld | bld | 309 | 57 | |
| Cu | 251 (8) | 93 | 10 | 3 | 7 | 24 | 10 | 74 | 21 |
| Zn | 1250 (50) | 670 | 102 | 74 | 69 | 154 | 105 | 1530 | 2480 |
| As | 0 | 0 | 5 | 1 | bld | bld | 72 | 64 | |
| Zn/Cu | 4.9 | 7.0 | 10.2 | 24.7 | 9.9 | 6.4 | 10.5 | 20.7 | 38.8 |
| TM (μg/mg) | 14.5 (2) | 0.89 (9) | 7.2 (6) | 84.5 (8) | |||||
| EM (μg/mg) | 12.9 (2) | 0.29 (6) | 3.4 (9) | 52.5 (4) | |||||
| PM(BT) (μg/mg) | 0.02 (1) | 0.050 (3) | 0.5 (3) | 1.72 (3) | |||||
| PM(BZ) (μg/mg) | 1.6 (1) | 0.55 (5) | 3.4 (1.2) | 30.3 (4) | |||||
| PM(BT)/TM | 0.14% | 6.12% | 6.27% | 2.03% | |||||
| PM(BZ)/TM | 11.03% | 61.80% | 43.70% | 35.86% | |||||
a2σ errors on concentrations due to counting statistics range from 4% (e.g., Ca, Zn) to 40% (e.g., Mn) relative, with indicative errors for the concentration ranges presented here given in the first column as errors on the terminal digits in parentheses
bNot discriminated from sedimentary matrix background. Point analyses from SSRL beamline 6-2 and DLS beamline I18. Standard error for the terminal digits of the melanin data also shown in parentheses
TM = EM + PM(BT) + PM(BZ). TM indicates total melanin, EM is eumelanin
PM(BT): Pheomelanin derived from benzothiazine (BT) units, as determined by hydroiodic acid hydrolysis – HPLC
PM(BZ): Pheomelanin derived from benzothiazole (BZ) units, as determined by AHPO – HPLC 24