• Figure 1.
    Download figureOpen in new tabFigure 1. Location of Rising Star Cave and the Dinaledi Chamber.

    (a) Simplified geological map showing the position of the Rising Star Cave (in grey); (b) close-up map of the Dinaledi Chamber showing the distribution of the dating samples, including: U-Th flowstone samples (yellow dots, black text); ESR samples (purple dots, orange text); and OSL samples (red dots, blue text). Age estimates for the different samples are shown, with cross reference to Tables 1, 7 and 8.

    DOI: http://dx.doi.org/10.7554/eLife.24231.003

    Figure 2.
    Download figureOpen in new tabFigure 2. Geological face map and cross-sections through the sediment pile at different locations in the Dinaledi Chamber, illustrating the relationships between the flowstone groups and sedimentary units.

    The positions of the section lines are shown in (a); a face map of the entry zone of the Dinaledi Chamber (looking NE) is shown in (b); geological cross-sections through the central part of the Dinaledi Chamber near the excavation pit are shown in (c) and (d).

    DOI: http://dx.doi.org/10.7554/eLife.24231.004

    Figure 3.
    Download figureOpen in new tabFigure 3. Field and close-up photographs of all flowstone samples collected for U-Th dating.

    The flowstone groups (i.e., Flowstone Groups 1, 2 or 3), sample numbers, and ages (2σ uncertainty), as listed in Table 1, are shown below each sample. Ages reported here are from JCU, unless otherwise stated.

    DOI: http://dx.doi.org/10.7554/eLife.24231.005

    Figure 4.
    Download figureOpen in new tabFigure 4. Location of the three H. naledi tooth samples (samples 1767, 1788 and 1810) and one baboon (cf. Papio) tooth sample (sample 1841) used for combined U-series and ESR dating.

    (a) Map of the Dinaledi Chamber showing the position of the excavation pit and the position of figures (b) and (c); (b) close-up of the SE corner of the excavation pit showing the sample site for sample 1810 and the 50 cm deep sondage from which sample 1841 was recovered; (c) the area to the W of the excavation pit from which samples 1767 and 1788 were collected.

    DOI: http://dx.doi.org/10.7554/eLife.24231.011

    Figure 5.
    Download figureOpen in new tabFigure 5. Samples of orange laminated mudstone of Unit 1 for OSL dating.

    (a) sample OSL3 with an estimated MAM age of 231 ± 41 ka taken from sub-unit 1b; (b) sample OSL4 with an estimated MAM age of 241 ± 37 ka, taken from sub-unit 1b and covered by a flowstone sheet dated at 290 ± 6 ka (RS5); (c) sample OSL5 with an estimated MAM age of 353 ± 61 ka, taken from sub-unit 1a and covered by a flowstone sheet dated at 32.1 ± 0.4 ka (RS20). The scale bar in each of the photographs is 10 cm.

    DOI: http://dx.doi.org/10.7554/eLife.24231.012

    Figure 6.
    Download figureOpen in new tabFigure 6. Photographs of H. naledi teeth used for ESR dating.

    (a) U.W.101–1767; (b) U.W.101–1788; (c) U.W.101–1810. The order of images for each panel is: buccal, distal, lingual, mesial, and occlusal views. The scale bar in each panel is 1 cm.

    DOI: http://dx.doi.org/10.7554/eLife.24231.013

    Figure 7.
    Download figureOpen in new tabFigure 7. Photographs of the baboon (cf. Papio) tooth (sample 1841), recovered from the sondage in the excavation pit, and used for ESR dating.

    Views are: (a) buccal, (b) occlusal, (c) lingual, and (d) internal.

    DOI: http://dx.doi.org/10.7554/eLife.24231.014

    Figure 8.
    Download figureOpen in new tabFigure 8. Cartoon illustrating the sedimentary history resulting in the deposition and redistribution of sediment of Units 2 and 3, and Flowstone Groups 1 to 3 in the Dinaledi Chamber.

    Note that all hominin fossils are contained in sub-unit 3b, but that this sub-unit has been repeatedly reworked after its initial deposition. Fossil entry occurred during the initial stages of deposition of Unit 3 below the entry shaft and predated deposition of Flowstone 1c. H. naledi fossils may have continued to enter the Dinaledi Chamber as older parts of Unit 3 were eroded from below Flowstone 1c, and as remnants of all older units were reworked to be incorporated into Unit 3 sediments that accumulated along the floor of the Dinaledi Chamber.

    DOI: http://dx.doi.org/10.7554/eLife.24231.019

    Figure 9.
    Download figureOpen in new tabFigure 9. Photographs illustrating the sampling approaches taken by SCU-UoW and GU-ANU in obtaining the U-Th results presented in Tables 4 and 5.

    (a) Comparison of sampling grids across the enamel-dentine boundary measured by SCU-UoW (red lines) vs. GU-ANU (blue circles). SCU-UoW (red lines) measured a series of parallel, shallow (<5 μm) pits along grid lines across the teeth and averaged U concentrations across each grid. GU-ANU (blue circles) measured the average composition of the tooth in single spots that were laser-bored along profiles across the teeth, and report results for each spot. (b, c) Locations of LA-ICP-MS spot analyses for teeth samples 1788 (b) and 1810 (c) conducted by GU-ANU. The detailed transects are shown in panels (d) to (h).

    DOI: http://dx.doi.org/10.7554/eLife.24231.020

    Figure 10.
    Download figureOpen in new tabFigure 10. Gamma dose rate reconstructions derived from analytical data of sediment samples collected around ESR samples 1767, 1788 and 1810 (closed circles and diamonds), combined with samples from a vertical profile in the excavation pit and sondage (open circles and diamonds).

    The data show little variation in dose rate with depth (see text for explanation).

    DOI: http://dx.doi.org/10.7554/eLife.24231.021

    Figure 11.
    Download figureOpen in new tabFigure 11. ESR dose response curves (DRC’s) obtained for the samples 1767, 1788, 1810 and 1841.

    To facilitate comparison, all DRC’s have been normalised to the intensity of the natural point (=1).

    DOI: http://dx.doi.org/10.7554/eLife.24231.023

    Figure 12.
    Download figureOpen in new tabFigure 12. Evolution of the Imax/Imin ratio vs the irradiation dose for the four tooth samples.

    (see text for explanation).

    DOI: http://dx.doi.org/10.7554/eLife.24231.024

    Figure 13.
    Download figureOpen in new tabFigure 13. Samples and results of palaeomagnetic analyses forFlowstone 1a.

    (a) Outcrop photo of hanging erosion remnant of Flowstone 1a from which the palaeomagnetic sample was taken. The three flowstone phases separated by detrital horizons are clearly visible, and their magnetic polarity has been marked (N = normal; R = reverse). The stratigraphic top is towards the top of the photo; (b) close-up of a hand sample taken for palaeomagnetic analysis from Flowstone 1a in the Dinaledi Chamber. The sample is layered and comprises three distinct phases (from base to top: A-C marked in yellow) separated by thin clastic horizons that mark disconformities indicated with red dashed lines. The larger-scale extent of the three phases can be seen in (a); (c) intensity spectra, Zijderveld plots, and stereo plots for samples from phases A to C taken from (b). Phases B and C show normal polarity and phase A shows reversed and intermediate polarity directions.

    DOI: http://dx.doi.org/10.7554/eLife.24231.025

    Figure 14.
    Download figureOpen in new tabFigure 14. Chronostratigraphic summary of radio-isotopic dating results, and interpretation of the depositional ranges of stratigraphic units, flowstones and H.

    naledi fossils in the Dinaledi Chamber. Following the preferred US-ESR maximum age model and associated uncertainties for ESR samples 1788 and 1810, a maximum depositional age of 335 Ma was determined, while the minimum depositional age of 236 ka was constrained by Flowstone 1c (sample RS18), which covers H. naledi material in the entry zone.

    DOI: http://dx.doi.org/10.7554/eLife.24231.026

  • Table 1.

    Summary table of U-Th disequilibrium ages obtained for samples from the Dinaledi Chamber by James Cook University (JCU - 1) and the University of Melbourne (UoM - 2). The detailed analytical results are shown in Tables 2 and 3. Sample locations are shown in Figure 1b. The data are ranked by increasing age of the oldest flowstone horizon within the sample, based on the JCU ages. The grey shading highlights the different age groupings observed within the flowstones: 24–32 ka, ~50 ka, 88–105 ka, ~242 ka, ~290 ka and >440 ka. Ages are reported relative to 1950.

    DOI: http://dx.doi.org/10.7554/eLife.24231.006

    Sample IDFlowstone groupUnderlying unitAge1 (ka)1 (ka)Age2 (ka)2 (ka)
     RS19FS2sub-unit 3b24.70.224.530.43
     RS11FS3 (top to RS21)FS29.050.069.9460.063
     RS21FS2 (base to RS11)sub-unit 3b28.40.428.620.29
     RS10FS2sub-unit 3b (and bone)30.10.3
     RS20FS2sub-unit 1a (Facies 1a; OSL5)30.40.232.120.38
     RS6FS2sub-unit 1a, sub-unit 3b49.80.350.820.43
     RS15FS2 (blind duplicate of RS1)sub-unit 3b92.61.091.400.65
     RS1FS2 (blind duplicate of RS15)sub-unit 3b91.040.72
     RS8FS2 (below FS1a-e)sub-unit 3b95.01.096.290.69
     RS14FS2in drain, along dolostone wall100.11.296.200.36
     RS17FS2 (top to RS16)in drain, along dolostone wall102.60.898.61.4
     RS16FS2 (base to RS17)in drain, along dolostone wall104.01.999.11.4
     RS13FS2 (rim to RS18)sub-unit 3b88.460.67
     RS18FS1c (core to RS13)sub-unit 3b2425242.96.6
     RS5FS1sub-unit 1b (Facies 1b; OSL4)2906
     RS22FS1a (top to RS23)Unit 2equilibrium478+107/−41
     RS23FS1a (base to RS22)Unit 2equilibrium502+181/−53
     RS9n/a (surface outcrop)n/aequilibriumequilibrium
    • 1James Cook University (JCU), Advanced Analytical Centre.

    • 2University of Melbourne (UoM), paleochronology laboratory.

  • Table 2.

    U-Th data table for James Cook University. Uncertainties include: analytical error, decay constant uncertainty, and uncertainty on initial 230Th/232Th. Ages are reported relative to 1950 and assume an initial 230Th/232Th activity of 0.83 ± 0.5, and the equation given in Placzek et al. (2006). Decay constants for 234U and 230Th are from Cheng et al. (2013).

    DOI: http://dx.doi.org/10.7554/eLife.24231.007

    Sample IDU (ppm)234U/238U230Th/238U232Th/238UAge (ka BP)2σ (ka)234U/238Uinitial
    (activity)(activity)(corrected)(activity)
     RS112.3141.7720.0500.1440.0010.00010880.00000059.050.061.81840.0003
     RS190.6521.8550.0010.3870.0020.0021760.00000824.70.21.9890.001
     RS210.4211.9460.0010.4600.0040.0019200.00001528.40.42.1090.002
     RS100.8461.8850.0010.4660.0030.0007920.00000330.10.32.0530.001
     RS200.7951.8550.0010.4630.0030.0013630.00000530.40.22.0220.001
     RS60.5601.9660.0010.7470.0030.0009740.00000249.80.32.2630.002
     RS150.4001.9120.0011.1640.0080.004720.0000192.61.02.4840.007
     RS80.3281.8130.0031.1200.0080.003160.0000295.01.02.3730.007
     RS140.7341.6390.0951.0390.0080.002980.00002100.11.22.1750.008
     RS170.6801.6090.0011.0320.0050.0006790.000001102.60.82.1500.005
     RS160.9731.5830.0001.0240.0110.0004030.000006104.01.92.120.01
     RS180.1521.8480.0011.8560.0130.011750.0000524253.660.05
     RS50.0901.7280.0011.8180.0090.017320.0000529063.920.07
     RS230.3141.1870.0021.3150.0110.003460.00002>400
     RS220.3671.2090.0011.3220.0080.0001250.000001>400
     RS90.7371.0070.0021.0290.0040.0004620.000001>400
  • Table 3.

    U-Th data table for the University of Melbourne. Activity ratios are determined after Hellstrom (2003) and Drysdale et al. (2012). Ages are corrected for initial 230Th using Equation 1 of Hellstrom (2006), the decay constants of Cheng et al. (2013), and an initial 230Th/232Th activity of 1.5 ± 1.5. The initial 234U/238U ratios are calculated using corrected ages, which are reported relative to 1950.

    DOI: http://dx.doi.org/10.7554/eLife.24231.008

    Sample IDU (ppm)234U/238U230Th/238U232Th/238UAge (ka BP)2σ (ka)234U/238Uinitial
    (activity)(activity)(corrected)(activity)
     RS111.5181.8080.0030.15970.00090.00008750.00000049.9460.0631.8310.004
     RS190.5011.8840.0110.39160.00260.0043220.00001024.530.431.9470.011
     RS210.3611.9680.0110.46540.00300.00113420.000001928.620.292.0490.011
     RS200.6261.8780.0110.49250.00320.00238370.000004032.120.381.9610.011
     RS60.2762.0230.0040.78560.00210.004960.0001050.820.432.1810.004
     RS130.0762.0060.0041.18370.00470.0047860.00005888.460.672.2910.005
     RS150.3811.9340.0041.16610.00290.006390.0001291.370.652.2090.005
     RS140.6651.6260.0031.00100.00150.0012620.00001496.240.361.8220.003
     RS80.2571.8310.0041.13970.00340.0057460.00006096.290.692.0910.004
     RS170.5171.6370.0091.02480.00660.00239630.000003798.61.41.8410.010
     RS160.9051.5900.0100.99630.00670.00170990.000003799.11.41.7800.011
     RS180.1042.0010.0112.03200.01400.0205570.000041242.96.62.9870.027
     RS220.3241.2280.0071.30170.00830.00012010.0000008478+107/–41
     RS230.2061.2250.0071.30160.00930.0078180.000016502+181/–53
     RS90.8961.0100.0021.02040.00180.0009160.000012
  • Table 4.

    Summary table of U-Th disequilibrium ages obtained for the three H. naledi teeth (samples 1767, 1788 and 1810) and the baboon tooth (sample 1841) from the Dinaledi Chamber obtained by SCU-UoW. No age calculations were carried out for U concentrations of ≤0.5 ppm or U/Th ≤250 (indicated in red and underlined). Mean values in this table only incorporate values from which meaningful ages could be calculated (indicated in black), however all values (i.e., red and black) were averaged to obtain the relevant mean values reported in Table 4. All uncertainties are given as 2σ.

    DOI: http://dx.doi.org/10.7554/eLife.24231.009

    Sample1767U (ppm)U/Th230Th/238U234U/238UAge (ka)2s (ka)(234U/238U)i
    1767-1 D7.226852.1670.0246.2590.00943.51.16.9490.026
    1767-2 D7.759962.2610.0236.2820.01045.51.17.0090.030
    1767-3 D8.031962.2250.8256.2760.012
    1767-4 D8.559512.2090.0316.3010.00944.11.47.0070.030
    1767-5* E3.6912382.2590.0316.1970.05546.21.86.9240.126
    1767-6* E1.761082.2391.1336.1650.038
    1767-7* E2.151092.3370.9476.2310.024
    1767-8* E2.465182.2760.0216.2530.01946.11.16.9860.048
    Mean:
    1767 D7.848772.2120.0266.2810.00944.51.26.9880.029
    1767 E3.088782.2680.0266.2250.03746.21.46.9550.087
    Sample1788U (ppm)U/Th230Th/238U234U/238UAge (ka)2s (ka)(234U/238U)i
    1788-1 D6.673902.9670.0266.4230.01161.41.57.4530.054
    1788-2 D7.081763.3700.8336.4410.010
    1788-3 D7.17603.2063.1266.3940.049
    1788-4 D7.4513913.3130.0236.4450.01070.31.47.6450.056
    1788-5 D5.5244233.2690.0236.3490.01070.41.47.5310.052
    1788-6 D5.0740903.4160.0146.3780.01474.11.17.6340.054
    1788-7 D5.3947293.3850.0206.4000.01472.91.47.6400.054
    1788-8 D5.9332093.4270.0156.3930.01374.21.17.6540.054
    1788-9 D5.2443293.4490.0146.4130.01474.51.07.6850.052
    1788-10 D4.8931613.3900.0106.4030.01173.00.97.6450.052
    1788-11 D4.825563.3940.0146.4160.01472.91.07.6590.052
    1788-12 D5.4816063.3560.0176.3840.01472.31.17.6090.052
    1788-13 D5.048383.3170.0256.4200.01470.71.57.6230.058
    1788-14 D5.69933.2812.4266.4080.013
    1788-15 D5.03723.3153.7316.4270.014
    1788-16 E0.1331.78618.1493.8340.267
    1788-17 E0.68250.7529.1496.2480.273
    1788-18 E0.4160.80113.0536.2360.050
    1788-19 E0.0831.78336.2314.3010.288
    1788-20 E1.023062.9900.1175.5410.15475.19.36.6170.394
    1788-21* E0.33502.04127.1355.7930.141
    1788-22* E0.12301.51324.8015.9750.098
    1788-23* E0.25341.36817.0715.9880.079
    1788-24* E0.36901.23713.5556.1670.055
    1788-25* E0.411071.0848.6726.2060.033
    1788-26* E0.481021.30211.3336.3840.081
    1788-27* E0.491650.6867.7336.3670.037
    1788-28* E0.311671.6156.9755.6020.246
    1788-29* E0.4462.31111.8985.5760.306
    1788-30 E0.44620.9885.3106.0890.075
    1788-31 E0.2981.06619.2566.1510.056
    1788-32 E0.23950.99417.4516.3520.064
    1788-33 E0.4161.10321.6516.3440.049
    1788-34 E0.28511.34011.4506.3820.061
    1788-35 E0.3541.28621.0886.3210.062
    1788-36 E0.41151.21612.8966.3720.041
    1788-37 E0.3611.10617.0596.3130.073
    1788-38 E0.542792.8100.2376.3000.06458.912.27.2620.270
    Mean:
    1788 D5.5927933.3350.0186.4020.01371.51.27.6160.054
    1788 E0.782932.9000.1775.9200.10967.010.86.9360.332
    Sample1810U (ppm)U/Th230Th/238U234U/238UAge (ka)2s (ka)(234U/238U)i
    1810-1 D7.073483.2310.0215.8140.01777.91.67.0030.056
    1810-2 D8.294113.1120.0305.8630.01073.42.16.9860.062
    1810-3 D8.889793.1060.0275.9290.01072.11.87.0460.060
    1810-4 D9.198333.0490.0445.9930.01169.42.67.0790.066
    1810-5 D9.175082.9370.0475.9900.00766.22.87.0200.066
    1810-6 D9.12553.1436.9195.9810.012
    1810-7 D7.954323.0990.0185.9770.01371.11.37.0890.054
    1810-8 D8.844892.9860.0746.0350.060674.17.0880.084
    1810-9 D9.39159053.1220.0135.8700.00673.61.16.9990.052
    1810-10 D9.7878393.1650.0175.8730.01174.81.37.0240.054
    1810-11 D9.0372423.1740.0305.8880.01574.82.07.0430.058
    1810-12 D9.5396263.1570.0195.8890.00974.31.47.0360.054
    1810-13 D10.19102403.0940.0185.9040.00872.21.37.0160.052
    1810-14 D10.64144633.1550.0305.9580.01073.11.97.0990.058
    1810-15 E0.0051−0.384146.0361.9650.186
    1810-16 E0.0022−1.06048.1681.0140.108
    1810-17 E0.00415.40317.5732.3570.194
    1810-18 E0.24553.1959.1094.0540.062
    1810-19 E0.544264.0090.1865.0540.109130.821.86.8720.466
    1810-20 E0.853283.6250.1194.2870.137146.822.75.9840.524
    1810-21 E0.41485.0094.4744.4940.186
    1810-22 E0.1577.6908.2254.3490.351
    1810-23 E0.0329.9121.8435.1530.599
    1810-24 E0.0100.661166.0561.8770.144
    1810-25 E0.0227.4089.3864.9640.557
    1810-26* E0.7333.7624.1004.7350.100
    1810-27* E0.1435.2714.5104.2550.112
    1810-28* E0.1853.5418.0794.5620.081
    1810-29* E0.2593.5117.0954.5620.058
    1810-30* E0.2134.0275.2914.0730.149
    1810-31* E0.0913.87539.1364.0290.072
    1810-32* E0.0522.4699.0994.1870.072
    1810-33* E0.0612.60224.1694.4260.141
    1810-34* E0.9120103.1310.0684.5610.032105.27.05.7980.128
    1810-35 E1.0134.29115.5144.0850.025
    1810-36 E0.04996.2978.8904.0600.242
    1810-37 E0.145285.7533.9324.3850.234
    1810-38 E0.02555.68728.4904.2110.437
    1810-39 E0.01174.20331.0484.4740.314
    1810-40 E2.0915863.9930.0494.9930.037132.56.26.8140.146
    Mean:
    1810 D9.0753323.1070.0305.9220.014572.31.97.0400.060
    1810 E1.1010883.6900.1054.7240.0788128.814.46.5950.316
    Sample1841U (ppm)U/Th230Th/238U234U/238UAge (ka)2s (ka)(234U/238U)i
    1841-1 E2.51784.4153.2525.8510.035
    1841-2 E1.96514.2687.6315.8420.044
    1841-3 E2.372184.3190.0415.8710.021115.53.57.7580.090
    1841-4 E1.883504.2610.0465.8910.016112.63.67.7300.082
    1841-5 E2.52144.3780.0455.8460.032118.74.37.7840.124
    1841-6 E2.5124.4282.7445.8810.044
    1841-7 E2.4634.4841.7445.9460.044
    1841-8 E2.14474.4992.4675.9620.037
    Mean:
    1841 E2.252614.3190.0445.8690.023115.63.87.7570.099
  • Table 5.

    Summary table of U-Th disequilibrium ages obtained for two H. naledi teeth (samples 1788 and 1810) from the Dinaledi Chamber obtained by GU-ANU. No age calculations were carried out for U concentrations of ≤0.5 ppm or U/Th ≤250 (indicated in red and underlined). Negative U/Th values are due to the Th background being higher than the measured values. Mean values in this table only incorporate values from which meaningful ages could be calculated (indicated in black). All uncertainties are given as 2σ. CS = Closed System; Diff = diffusion (i.e., calculated ages are based on the assumption of continuous diffusion after Sambridge et al. (2012).

    DOI: http://dx.doi.org/10.7554/eLife.24231.010

    Sample 1810aU (ppm)U/Th230Th/238U234U/238UAge – CS (ka)2σ (ka)Age – Diff (ka)2σ (ka)(234U/238U)i*
     1 E0.03−273.71131.25084.43020.8881n/a
     2 E0.02−193.16480.93904.20830.4703n/a
     3 E0.04−333.02571.05315.12200.4988n/a
     4 E0.05−353.63521.38974.92240.4912n/a
     5 E0.19−2583.45040.19654.81060.1376n/a
     6 D6.07−29723.29090.06665.98010.055977.22.387.32.77.190.11
     7 D6.10−53543.26180.08245.97680.031276.32.686.23.37.170.08
     8 D6.39114363.31690.08005.98270.051477.92.688.33.37.210.11
     9 D6.4761933.33180.08995.94700.087379.03.289.73.87.180.17
     10 D6.65−50553.49850.10486.04620.040382.53.494.44.57.370.11
     11 D6.9551493.54650.09106.05310.040683.83.096.34.07.400.11
     12 D7.1532443.52380.09976.05010.042383.23.395.44.37.390.11
    Mean:
    1–5 E0.07 ± 0.063.43210.30034.79620.1504112.015.7137.125.5
    6–12 D6.54 ± 0.313.40180.07496.00700.042880.12.591.13.27.270.11
    Sample 1810bU (ppm)U/Th230Th/238U234U/238UAge – CS (ka)2σ (ka)Age – Diff (ka)2σ (ka)(234U/238U)i*
     1 E0.01176.844214.04350.02285.5626n/a
     2 E0.0039.233016.2333−2.28384.6085n/a
     3 E0.00–216.168827.6564−0.10337.6336n/a
     4 E0.00–314.9980967.0421−0.7695259.2590n/a
     5 E0.02−1827.1338296.11363.625048.0742n/a
     6 E0.86−24934.51760.17864.65880.0795189.116.7381.3137.97.240.44
     7 E0.98−6034.87970.14164.87370.0681201.414.00.00.07.840.40
     8 D4.49204233.57780.06705.93270.077387.12.7100.83.17.310.15
     9 D5.35−101283.30460.06595.91420.067778.72.489.22.87.140.13
     10 D5.67−41973.40770.07775.94800.045981.32.692.83.37.230.10
    Mean:
    1–5 E0.01 ± 0.018.7750204.69881.654793.9630n/a-----
    6–7 E0.92 ± 0.124.71010.14654.77300.0602195.713.8471.0269.47.540.42
    8–10 D5.17 ± 0.703.42140.07905.93190.052382.12.793.73.67.230.13
    Sample 1788aU (ppm)U/Th230th/238U234U/238UAge – CS (ka)2σ (ka)Age – Diff (ka)2σ (ka)(234U/238U)i*
     1E0.0348772.10953.30583.57401.6107n/a
     2E0.01−213.78455.52711.35252.7713n/a
     3E0.00–110.503027.8940−2.490910.1171n/a
     4E0.00–19.0249113.8912−0.712032.3636n/a
     5E0.00–26.679566.27500.776918.7506n/a
     6E0.01–63.02310.98442.19040.4875n/a
     7E0.24−1052.81390.20766.37910.1624n/a
     8E0.24−2041.64951.58116.01230.2961n/a
     9E0.195792.40754.26206.33411.3187n/a
     10E0.481893.17172.28626.10060.1341n/a
     11E1.34138333.87920.28646.35210.102488.59.2102.912.67.870.32
     12E2.577554.17700.06096.32750.097298.63.0117.73.18.040.19
    Mean:
    1–6 E0.01 ± 0.013.51884.45312.34717.1463n/a---
    7–10 E0.29 ± 0.132.64840.24696.18240.097856.26.561.07.7
    11–12 E1.96 ± 1.234.07460.09416.33610.048295.13.2112.34.77.960.26
    Sample 1788bU (ppm)U/Th230Th/238U234U/238UAge – CS (ka)2σ (ka)Age – Diff (ka)2σ (ka)(234U/238U)i*
     1E0.0242.39451.87743.50401.4368n/a
     2E0.02141.96561.32993.30990.9022n/a
     3E0.01–82.81562.10342.53590.8082n/a
     4E0.021602.102458.18543.23427.4009n/a
     5E0.03−312.38591.40844.12851.5222n/a
     6E0.03−202.895111.29114.10463.9747n/a
     7E0.02−102.84863.53834.93622.3343n/a
     8E0.03−182.83251.61135.70520.7139n/a
    Mean:
    1–8 E0.02 ± 0.012.55976.76184.13081.2209n/a
    Sample 1788cU (ppm)U/Th230th/238U234U/238UAge – CS (ka)2σ (ka)Age – Diff (ka)2σ (ka)(234U/238U)i*
     1D5.44215783.92810.07076.42600.074088.62.6103.03.17.970.15
     2D5.391550373.89080.05656.44160.052487.22.0101.02.47.960.11
     3D4.9517083.89010.08286.40850.079287.83.0102.03.67.930.16
     4D3.8716533.80330.08596.37860.106885.83.399.03.67.850.20
     5D4.2511683.95690.08006.40510.095790.03.1105.03.67.970.19
     6D5.1214933.94330.05796.49510.096187.82.5102.02.58.040.17
     7D5.3426593.80200.05816.47130.058184.02.096.72.47.940.11
     8D5.0610933.99480.06726.44790.063090.32.4105.53.08.030.13
     9D4.7810184.04810.07186.44680.058692.02.5108.03.38.060.13
     10D5.228173.90110.05826.51870.081386.12.399.62.48.040.15
     11D5.254253.88720.08506.44150.062487.12.8101.03.67.960.14
     12D5.463453.95610.05846.46580.073388.82.3103.32.58.030.14
    Mean:
    1–12 D5.01 ± 0.283.91750.07966.44790.046187.92.6102.03.67.980.06
  • Table 6.

    Summary table of model parameters used in ESR dating separated by sample number and laboratory. See text for detailed discussion.

    DOI: http://dx.doi.org/10.7554/eLife.24231.015

    Sample:1767178818101841
    Laboratory:SCUSCUCenieh-guSCUCenieh-guSCU
    Enamel:
    De (Gy)194 ± 4231 ± 8159 ± 10296 ± 14232 ± 301676 ± 127
    U (ppm)2.52 ± 0.530.38 ± 0.170.07 ± 0.070.32 ± 0.120.16 ± 0.162.28 ± 0.48
    234U/238U6.21 ± 0.035.95 ± 0.326.258 ± 0.3494.04 ± 0.184.773 ± 0.0605.87 ± 0.03
    230Th/234U0.37 ± 0.050.55 ± 0.520.598 ± 0.0380.92 ± 0.050.950 ± 0.0340.785 ± 0.038
    Alpha efficiency*0.13 ± 0.020.13 ± 0.020.13 ± 0.020.13 ± 0.020.13 ± 0.020.13 ± 0.02
    Initial thickness (μm)1027 ± 2101049 ± 2771486 ± 2481150 ± 2501527 ± 257650 ± 145
    Water (%)000000
    Dentine:
    U (ppm)7.88 ± 0.665.76 ± 0.864.71 ± 0.279.08 ± 0.445.81 ± 0.37
    234U/238U6.28 ± 0.096.40 ± 0.036.448 ± 0.0465.93 ± 0.035.969 ± 0.035
    230Th/234U0.35 ± 0.110.62 ± 0.020.608 ± 0.0120.52 ± 0.090.572 ± 0.010
    Water (%)10 ± 510 ± 510 ± 510 ± 510 ± 5
    Sediment:
    U (ppm)3.0 ± 0.32.9 ± 0.12.9 ± 0.13.2 ± 0.33.2 ± 0.30.64 ± 0.06
    Th (ppm)7.9 ± 0.48.3 ± 0.68.3 ± 0.68.6 ± 0.48.6 ± 0.44.72 ± 0.47
    K (%)1.17 ± 0.141.21 ± 0.141.21 ± 0.141.23 ± 0.141.23 ± 0.141.47 ± 0.15
    Water (%)25 ± 1025 ± 1025 ± 1025 ± 1025 ± 1025 ± 10
    Depth below ground surface (cm)0225555
    Gamma Dose rate (μGy a−1)
    25 ± 10% Water, 80% Rn degassing
    25 ± 10% Water, no Rn degassing
    534 ± 69
    724 ± 116
    534 ± 69
    724 ± 116
    534 ± 69
    724 ± 116
    534 ± 69
    724 ± 116
    534 ± 69
    724 ± 116
    534 ± 69
    724 ± 116
    Cosmic dose rate (μGy a−1)15 ± 115 ± 115 ± 115 ± 115 ± 115 ± 1
    • *After Woodroffe et al. (1991);

    • A relative error of ± 10% was assumed.

  • Table 7.

    Summary of ESR dating results (2σ uncertainties) for two end-member scenarios: (i) complete burial of the samples, 80% Rn loss in the sediment and post Th-230 equilibrium in dental tissue (i.e., maximum age scenario); (ii) complete burial of the samples and post-Rn equilibrium in sediment (i.e., minimum age scenario). See text for detailed discussion.

    DOI: http://dx.doi.org/10.7554/eLife.24231.016

    Sample:1767178818101841
    Laboratory:SCUSCUCenieh-guSCUCenieh-guSCU
     Scenario 1: 25 ± 10% Water, complete burial and 80% 222Rn degassing (maximum age scenario)
    internal dose rate (μGy a−1)1142 ± 515190 ± 12947 ± 47323 ± 175176 ± 1761411 ± 596
    alpha (μGy a−1)*008 ± 208 ± 20
    beta dose rate, dentine (μGy a−1)73 ± 3391 ± 6264 ± 1675 ± 4151 ± 14
    beta dose rate, sediment (μGy a−1)101 ± 24105 ± 3186 ± 1795 ± 2486 ± 18358 ± 74
    gamma and cosmic (μGy a−1)549 ± 69549 ± 69549 ± 69549 ± 69549 ± 69549 ± 69
    total dose rate (μGy a−1)1865 ± 521935 ± 162754 ± 871042 ± 194870 ± 1902318 ± 606
    p enamel−0.030.49−0.02−0.70−0.770.91
    p dentine0.080.13−0.061.020.54
    Age (ka)104 ± 29247 ± 42211 ± 28284 ± 51267 ± 68723 ± 181
    Combined SCU/CENIEH-GU age (ka)229 + 60/–46276 + 59/–77
    Average age for 1788 & 1810 (ka)253 + 82/–70
     Scenario 2: 25 ± 10% Water, complete burial and no 222Rn degassing (minimum age scenario)
    internal dose rate (μGy a−1)1277 ± 552216 ± 16551 ± 51335 ± 193184 ± 1841520 ± 630
    alpha (μGy a−1)*008 ± 208 ± 20
    beta dose rate, dentine (μGy a−1)82 ± 35102 ± 7869 ± 1887 ± 5059 ± 16--
    beta dose rate, sediment (μGy a−1)132 ± 26134 ± 33111 ± 19126 ± 26112 ± 19380 ± 81
    gamma and cosmic (μGy a−1)739 ± 116739 ± 116739 ± 116739 ± 116739 ± 116739 ± 116
    total dose rate (μGy a−1)2230 ± 5861191 ± 219978 ± 1291287 ± 2321102 ± 2192639 ± 647
    p enamel−0.310.06−0.37−0.83−0.910.67
    p dentine−0.22−0.22−0.400.540.10
    Age (ka)87 ± 22194 ± 34163 ± 24230 ± 40210 ± 50635 ± 148
    Combined SCU/CENIEH-GU age (ka)179 + 49/–40220 + 50/–60
    Average age for 1788 & 1810 (ka)200 + 70/–61
    • *using alpha attenuation values of Grün (1987).

    • considered as negligible given the low radioelement concentrations in the sediment and the high total dose rate value.

    • for 1841, the beta dose rate on both sides of the enamel layer is derived from the sediment.

  • Table 8.

    Summary of OSL results obtained by the University of the Witwatersrand for samples of Unit 1 from the Dinaledi Chamber (samples OSL3, 4 and 5). The ages were calculated using effective U concentration values (taking disequilibrium into account; see text for details). CAM = Central Age Model; MAM = Minimum Age Model.

    DOI: http://dx.doi.org/10.7554/eLife.24231.017

    Sample IDH2O (%)Th (ppm)U (ppm) pre-RnU (ppm) post-RnK (%)Total dr (Gy/ka)Total de (Gy) CAMTotal de (Gy) MAMCAM
    Age (ka)
    CAM
    MAM age (ka)MAM 2σOver dispersion
    (%)
    OSL318.9 ± 53.71 ± 1.600.75 ± 0.1770.193 ± 0.0440.45 ± 0.120.760.07428.5968.92176.427.75601032314163
    OSL425.8 ± 53.38 ± 1.600.485 ± 0.1770.097 ± 0.0440.47 ± 0.120.700.06379.8943.58168.020.7546792413755
    OSL522.7 ± 55.11 ± 1.600.692 ± 0.1770.138 ± 0.0440.56 ± 0.120.900.07759.54102.33315.6748.688491323536168
  • Table 9.

    Final mean palaeomagnetic data for all subsamples analysed from each phase of Flowstone 1a as shown in Figure 13. MAD = mean maximum angular deviation for individual samples; K = precision/sample dispersal parameter; Plat = palaeolatitude).

    DOI: http://dx.doi.org/10.7554/eLife.24231.018

    Flowstone 1aDeclination (O)Inclination (O)MADKPlat.Polarity
     Phase C15.5−39.7370.875.4N
     Phase B26−28.17.4156.263.3N
     Phase A156.415.95.730.2−60.0R
  • Table 10.

    ESR fitting results obtained by SCU and CENIEH-GU. Both laboratories employed a Single Saturating Exponential (SSE) fitting function. Dmax was selected in accordance with Duval and Grün (2016) to avoid DE overestimation. SCU results in brackets show DE values that were obtained by SCU using the CENIEH-GU procedure (see text for details).

    DOI: http://dx.doi.org/10.7554/eLife.24231.022

    SCUCenieh-gu
    SampleDE (Gy)Dmax (Gy)Dmax/DEDE (Gy)Dmax (Gy)Dmax/DE
    1767194 ± 4 (193 ± 6)12647
    1788232 ± 8 (232 ± 22)12045159 ± 11164910
    1810296 ± 14 (281 ± 34)27359232 ± 2916497
    18411676 ± 127 (1648 ± 500)35262