Revised stratigraphy and chronology for Homo floresiensis at Liang Bua in Indonesia

Journal name:
Nature
Volume:
532,
Pages:
366–369
Date published:
DOI:
doi:10.1038/nature17179
Received
Accepted
Published online

Homo floresiensis, a primitive hominin species discovered in Late Pleistocene sediments at Liang Bua (Flores, Indonesia)1, 2, 3, has generated wide interest and scientific debate. A major reason this taxon is controversial is because the H. floresiensis-bearing deposits, which include associated stone artefacts2, 3, 4 and remains of other extinct endemic fauna5, 6, were dated to between about 95 and 12 thousand calendar years (kyr) ago2, 3, 7. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago8, 9, 10. Here we report new stratigraphic and chronological evidence from Liang Bua that does not support the ages inferred previously for the H. floresiensis holotype (LB1), ~18 thousand calibrated radiocarbon years before present (kyr cal. bp), or the time of last appearance of this species (about 17 or 13–11 kyr cal. bp)1, 2, 3, 7, 11. Instead, the skeletal remains of H. floresiensis and the deposits containing them are dated to between about 100 and 60 kyr ago, whereas stone artefacts attributable to this species range from about 190 to 50 kyr in age. Whether H. floresiensis survived after 50 kyr ago—potentially encountering modern humans on Flores or other hominins dispersing through southeast Asia, such as Denisovans12, 13—is an open question.

At a glance

Figures

  1. Site location.
    Figure 1: Site location.

    a, Location of Flores within Indonesia. b, Location of Liang Bua on Flores. c, Site plan of Sectors discussed in the text (the 2001–2004 and 2007–2014 excavations are shaded red and blue, respectively). The remaining cave floor sediments are shaded white, while the areas shaded brown are exposed rocks, stalagmites and other surfaces covered in speleothems.

  2. Composite stratigraphic section of deposits at Liang Bua, with approximate ages.
    Figure 2: Composite stratigraphic section of deposits at Liang Bua, with approximate ages.

    The deposits accumulated above a fluvial conglomerate and are capped by recent sediments (both shown in grey). Skeletal remains of Homo floresiensis occur in deposits stratigraphically beneath a sequence of eight volcanic tephras (T1–T8), separated by calcitic speleothems (blue) and fine-grained clastic sediments (green). As the thickness, grain size and slope angle of each unit vary considerably within the cave, only the approximate relative thicknesses of the units discussed in the text are shown; the minimum depth of this composite section would exceed 15 m. See Fig. 3 and Extended Data Fig. 5a for three-dimensional representations of the stratigraphy. Also indicated are units with concentrations of rounded, gravel-size clasts of igneous rock (red) or irregularly shaped, eroded fragments of T1, T2 and T3 (orange), and units with signs of bioturbation (upper parts of T3 and T7). The photograph shows T1–T5 and interstratified sediments that conformably overlie the H. floresiensis-bearing deposits (south baulk of Sector XXI).

  3. Stratigraphy of excavated Sectors near the eastern wall of the cave.
    Figure 3: Stratigraphy of excavated Sectors near the eastern wall of the cave.

    Multiple specimens of Homo floresiensis (LB1, LB4, LB6 and LB8) were recovered previously1, 2, 3, 14, 15, 16, 17, 18, 19, 20 from sediments now recognized to directly underlie a sequence of five tephras (T1–T5) and interstratified deposits. Together, these remnant deposits form a pedestal, the top of which is dated to ~46 kyr cal. bp (charcoal sample denoted by the red star at ~2 m depth in Sector XXIII). The overlying section—separated here by a white band and dotted lines for emphasis—represents deposits (including three additional tephras, T6–T8) that rest unconformably on the steeply sloping erosional surface of the pedestal. The green stars in Sector VII mark the respective locations (from top to bottom) of the charcoal samples dated to approximately 13.0, 18.5, 18.1, 19.0 and 19.2 kyr cal. bp, which were used erroneously2, 3, 7 to infer the latest occurrences of H. floresiensis.

  4. Stratigraphy of the excavated area near the eastern cave wall at eight stages of depositional history, with approximate ages indicated.
    Extended Data Fig. 1: Stratigraphy of the excavated area near the eastern cave wall at eight stages of depositional history, with approximate ages indicated.

    a–h, Each panel shows the remnant deposits exposed in the 2-m-wide baulks of the following Sectors (from left to right): north VII, east VII, XI and XXIII, south XXIII and XXI, west XXI, XV and XVI, and north XVI. The pedestal deposits shown in b–d were truncated by one or more phases of erosion that resulted in an erosional surface (that is, an unconformity) that slopes steeply down towards the cave mouth (see also Supplementary Video 1). The black arrows relate to the accompanying text in each panel. The maximum depth excavated was 10.75 m in Sector VII (for example, the left two panels in h).

  5. Deposits containing the remains of Homo floresiensis.
    Extended Data Fig. 2: Deposits containing the remains of Homo floresiensis.

    These deposits (A) consist of multiple layers of fine-grained sediment interspersed with layers of weathered limestone and loose gravel, and are directly overlain by two tephras (T1 and T2). a, South baulk of Sector XV, near the eastern cave wall. b, West baulk of Sector XV, also showing the unconformably overlying deposits (B). c, d, North and east baulks of Sector XIX, near the cave centre.

  6. The volcaniclastic deposits at Liang Bua.
    Extended Data Fig. 3: The volcaniclastic deposits at Liang Bua.

    a, Photograph of tephras T6–T8 (north baulk of Sector XVI). b, Photograph of tephras T1–T5 (south baulk of Sector XXI). c, Bivariate plot of FeO and CaO concentrations (expressed as weight %), acquired by electron microprobe analysis of glass shards from T1 (n = 6), T3 (n = 4), T5 (n = 10) and T7 (n = 15), as well as the Youngest Toba Tuff (YTT, n = 207, ± 1σ) from northern Sumatra. d, Bivariate plot of FeO and K2O concentrations (symbols as in c). e, Bivariate plot of SiO2 and Na2O + K2O concentrations (symbols as in c). f, Isotope correlation (inverse isochron) plot for hornblende crystals from T1. The error ellipses represent individual analyses (n = 28). The ellipse on the far right-hand side was omitted from the 40Ar/39Ar age determination of 79 ± 12 kyr (at 1σ).

  7. Erosional surface of the pedestal in the west baulks of Sectors XV and XVI.
    Extended Data Fig. 4: Erosional surface of the pedestal in the west baulks of Sectors XV and XVI.

    The dashed line marks the steeply sloping boundary between remnant deposits (T2, T1 and the underlying Homo floresiensis-bearing sediments) that comprise part of the pedestal (A) and the much younger deposits (B) that unconformably overlie the contact. a, Photograph taken at an upward angle showing the sedimentary differences between the deposits above and below the erosional boundary. b, Illustration of the erosional surface and underlying deposits shown in a.

  8. Erosional surface of the pedestal near the eastern wall of the cave.
    Extended Data Fig. 5: Erosional surface of the pedestal near the eastern wall of the cave.

    a, Illustration of the erosional surface and the locations of LB1, LB4, LB6 and LB8 below the boundary (see also Fig. 3). The deposits that unconformably overlie the pedestal are shown in the south and west baulks. The stippled cube outlines the photographed area (in Sector XV) shown in b and c. Both photographs taken from above, with north towards the bottom of the page.

  9. Locations of sediment samples dated in this study and TL data for quartz grains from Liang Bua.
    Extended Data Fig. 6: Locations of sediment samples dated in this study and TL data for quartz grains from Liang Bua.

    a, Stratigraphy of the excavated area near the eastern cave wall (Sector baulks as in Extended Data Fig. 1) with TL samples indicated by red circles, IRSL samples by blue circles and the 40Ar/39Ar sample by a yellow square. Also shown are the TL and IRSL sample codes and the locations of hominin remains LB1 and LB6. b, Representative isothermal (260 °C) TL decay curves for the natural (black line) and test dose (grey line) signals from sample LB08-15-3. c, d, Regenerated TL dose–response curves for one pair of Aliquots A and B of sample LB08-15-3, respectively; the equivalent dose (De) is estimated by projecting the natural signal (red square) on to the dose–response curve fitted to the regenerated signals (blue diamonds). e, Radial plot47, 48 of De values for Aliquot A (n = 12) of sample LB08-15-3; the grey band is centred on the weighted mean De calculated using the central age model. f, Radial plot of the corresponding De values for Aliquot B (n = 12) of the same sample. The grey band is centred on the central age model estimate, with the two high-De outliers omitted. The red line intersects the right-hand axis at the De calculated by fitting the minimum age model47, 48 to all 12 values. g, h, Radial plots of De values for Aliquots A and B of sample LB12-23-1 (symbols as in e and f).

  10. IRSL data and potassium (K) concentrations for feldspar grains from Liang Bua.
    Extended Data Fig. 7: IRSL data and potassium (K) concentrations for feldspar grains from Liang Bua.

    a, Representative IRSL (50 °C) and multiple elevated temperature (100–250 °C) post-infrared IRSL (pIRIR) decay curves for a single aliquot of sample LB12-OSL1. b, IRSL (50 °C) and pIRIR (290 °C) decay curves for a different aliquot of LB12-OSL1. c, Regenerated pIRIR (290 °C) dose–response curve for the aliquot shown in b; the equivalent dose (De) is estimated by projecting the natural signal (red square) on to the dose–response curve fitted to the regenerated signals (blue diamonds). d–j, Radial plots of IRSL ages (corrected for residual dose and anomalous fading) for single aliquots of each sample: d, LB12-OSL1; e, LB12-OSL2; f, LB12-OSL3; g, LB12-OSL4; h, LB12-OSL5; i, LB12-OSL6; and j, LB12-OSL7. IRSL ages were also obtained for single grains of samples LB12-OSL3 and LB12-OSL4, and are shown as open triangles in f and g. The grey bands in each plot are centred on the weighted mean ages calculated using the central age model. k, l, Radial plots of IRSL ages (corrected as for d–j) for samples LBS7-40a and LBS7-42a, respectively; single aliquots are shown as filled circles and single grains as open triangles. The upper and lower red lines intersect the right-hand axis at the maximum and minimum single-grain ages, respectively. m, Distribution of pIRIR intensities from 28 individual grains of feldspar from sample LB12-OSL3 that had been given a regenerative dose of 80 Gy. The relative contribution of each grain to the total (cumulative) pIRIR light sum is plotted as a function of K concentration (measured by wavelength-dispersive X-ray spectroscopy); note the reversed scale on the x-axis. n, Cumulative pIRIR light sum for the same 28 grains as shown in m, plotted as a function of grains ranked by K concentration (which decreases from left to right).

  11. Laser-ablation uranium-series analyses of hominin bone fragments from various Sectors and spits (depth intervals), and their modelled ages.
    Extended Data Fig. 8: Laser-ablation uranium-series analyses of hominin bone fragments from various Sectors and spits (depth intervals), and their modelled ages.

    a, Modern human femur (132A/LB/27D/03) from Sector IV, spit 27 (265–275 cm). b, Homo floresiensis ulna (LB1/52) from Sector XI, spit 58A (575–585 cm). c, H. floresiensis ulna (LB2/1) from Sector IV, spit 42D (415–425 cm). d, H. floresiensis ulna (LB6/3) from Sector XI, spit 51 (505–515 cm). Each laser spot is 265 μm in diameter and the age errors are at 2σ.

  12. Laser-ablation uranium-series analyses of bone fragments of Stegodon florensis insularis from various spits (depth intervals) in Sector XI, and their modelled ages.
    Extended Data Fig. 9: Laser-ablation uranium-series analyses of bone fragments of Stegodon florensis insularis from various spits (depth intervals) in Sector XI, and their modelled ages.

    a, U-s-01/LB/XI/32/04, spit 32 (315–325 cm). b, U-s-02/LB/XI/45/04, spit 45 (445–455 cm). c, U-s-03/LB/XI/47/04, spit 47 (465–475 cm). d, U-s-04/LB/XI/49/04, spit 49 (485–495 cm). e, U-s-05/LB/XI/51/04, spit 51 (505–515 cm). f, U-s-06/LB/XI/52/04, spit 52 (515–525 cm). g, U-s-07/LB/XI/65/04, spit 65 (645–655 cm). h, U-s-08/LB/XI/65B/04, spit 65B (645–655 cm). Each laser spot is 265 μm in diameter and the age errors are at 2σ.

  13. Deposits stratigraphically above the unconformity in Sector XVI and displaced slab of deposit in Sector XXII.
    Extended Data Fig. 10: Deposits stratigraphically above the unconformity in Sector XVI and displaced slab of deposit in Sector XXII.

    a, The north baulk (~2 m wide) of Sector XVI. b, Excavated floors (white arrow points north) of spits 61–63 (615–635 cm depth); the field of view is ~1.6 m in width. The stippled box in a indicates the floor of spit 63 in b, where fragments of T1 (+) are visible in spit 63, and fragments of T3 (*) and T1 are concentrated in the band just above the label for spit 61. Eroded fragments (between about 1 cm and 60 cm in size) of T1, T2 and T3 have been consistently recovered from deposits unconformably overlying the erosional surface of the pedestal, indicating reworking of the pedestal deposits before ~13 kyr cal. bp. c, Photograph of the west baulk and parts of the south and north baulks (at left and right, respectively) of Sector XXII showing a displaced slab of deposit that contains intact portions of the uppermost part of T3 (arrow) and the overlying layers, up to and including the flowstone (fs) that caps T5. The stratigraphic position of the slab beneath T7 and T8 indicates that it broke away from its original location, slightly to the south, and slid down the steeply sloping erosional surface before ~13 kyr cal. bp. Also shown are the Homo floresiensis-bearing deposits (A) and the unconformably overlying deposits (B), which include eroded fragments of T1 (+), T2 (#) and T3 (*). d, Illustration of the west baulk of Sector XXII, as shown in c.

Videos

  1. Animated summary of the stratigraphy and chronology of the Liang Bua depositional sequence.
    Video 1: Animated summary of the stratigraphy and chronology of the Liang Bua depositional sequence.
    Animated summary of the stratigraphy and chronology of the Liang Bua depositional sequence.

References

  1. Brown, P. et al. A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia. Nature 431, 10551061 (2004)
  2. Morwood, M. J. et al. Archaeology and age of a new hominin from Flores in eastern Indonesia. Nature 431, 10871091 (2004)
  3. Morwood, M. J. et al. Further evidence for small-bodied hominins from the Late Pleistocene of Flores, Indonesia. Nature 437, 10121017 (2005)
  4. Moore, M. W., Sutikna, T., Jatmiko, Morwood, M. J. & Brumm, A. Continuities in stone flaking technology at Liang Bua, Flores, Indonesia. J. Hum. Evol. 57, 503526 (2009)
  5. van den Bergh, G. D. et al. The Liang Bua faunal remains: a 95 k.yr. sequence from Flores, East Indonesia. J. Hum. Evol. 57, 527537 (2009)
  6. Meijer, H. J. M. et al. Late Pleistocene–Holocene non-passerine avifauna of Liang Bua (Flores, Indonesia). J. Vertebr. Paleontol. 33, 877894 (2013)
  7. Roberts, R. G. et al. Geochronology of cave deposits at Liang Bua and of adjacent river terraces in the Wae Racang valley, western Flores, Indonesia: a synthesis of age estimates for the type locality of Homo floresiensis. J. Hum. Evol. 57, 484502 (2009)
  8. Roberts, R. G. et al. Thermoluminescence dating of a 50,000-year-old human occupation site in northern Australia. Nature 345, 153156 (1990)
  9. Bowler, J. M. et al. New ages for human occupation and climatic change at Lake Mungo, Australia. Nature 421, 837840 (2003)
  10. Clarkson, C. et al. The archaeology, chronology and stratigraphy of Madjedbebe (Malakunanja II): a site in northern Australia with early occupation. J. Hum. Evol. 83, 4664 (2015)
  11. Morwood, M. J. et al. Preface: research at Liang Bua, Flores, Indonesia. J. Hum. Evol. 57, 437449 (2009)
  12. Reich, D. et al. Genetic history of an archaic hominin group from Denisova Cave in Siberia. Nature 468, 10531060 (2010)
  13. Reich, D. et al. Denisova admixture and the first modern human dispersals into Southeast Asia and Oceania. Am. J. Hum. Genet. 89, 516528 (2011)
  14. Falk, D. et al. The brain of Homo floresiensis. Science 308, 242245 (2005)
  15. Larson, S. G. et al. Homo floresiensis and the evolution of the hominin shoulder. J. Hum. Evol. 53, 718731 (2007)
  16. Tocheri, M. W. et al. The primitive wrist of Homo floresiensis and its implications for hominin evolution. Science 317, 17431745 (2007)
  17. Jungers, W. L. et al. The foot of Homo floresiensis. Nature 459, 8184 (2009)
  18. Morwood, M. J. & Jungers, W. L. (Eds). Paleoanthropological Research at Liang Bua, Flores, Indonesia. J. Hum. Evol. 57, 437648 (2009)
  19. Kaifu, Y. et al. Craniofacial morphology of Homo floresiensis: description, taxonomic affinities, and evolutionary implication. J. Hum. Evol. 61, 644682 (2011)
  20. Orr, C. M. et al. New wrist bones of Homo floresiensis from Liang Bua (Flores, Indonesia). J. Hum. Evol. 64, 109129 (2013)
  21. Li, B., Jacobs, Z., Roberts, R. G. & Li, S.-H. Review and assessment of the potential of post-IR IRSL dating methods to circumvent the problem of anomalous fading in feldspar luminescence. Geochronometria 41, 178201 (2014)
  22. Westaway, K. E. & Roberts, R. G. A dual-aliquot regenerative-dose protocol (DAP) for thermoluminescence (TL) dating of quartz sediments using the light-sensitive and isothermally stimulated red emissions. Quat. Sci. Rev. 25, 25132528 (2006)
  23. Grün, R., Eggins, S., Kinsley, L., Moseley, H. & Sambridge, M. Laser ablation U-series analysis of fossil bones and teeth. Palaeogeogr. Palaeoclimatol. Palaeoecol. 416, 150167 (2014)
  24. Sambridge, M., Grün, R. & Eggins, S. U-series dating of bone in an open system: the diffusion–adsorption–decay model. Quat. Geochronol. 9, 4253 (2012)
  25. Storey, M., Roberts, R. G. & Saidin, M. Astronomically calibrated 40Ar/39Ar age for the Toba supereruption and global synchronization of late Quaternary records. Proc. Natl Acad. Sci. USA 109, 1868418688 (2012)
  26. Rivera, T. A., Storey, M., Schmitz, M. D. & Crowley, J. L. Age intercalibration of 40Ar/39Ar sanidine and chemically distinct U/Pb zircon populations from the Alder Creek Rhyolite Quaternary geochronology standard. Chem. Geol. 345, 8798 (2013)
  27. Westaway, K. E. et al. Homo floresiensis and the late Pleistocene environments of eastern Indonesia: defining the nature of the relationship. Quat. Sci. Rev. 28, 28972912 (2009)
  28. Westaway, K. E. et al. Establishing the time of initial human occupation of Liang Bua, western Flores, Indonesia. Quat. Geochronol. 2, 337343 (2007)
  29. Mijares, A. S. et al. New evidence for a 67,000-year-old human presence at Callao Cave, Luzon, Philippines. J. Hum. Evol. 59, 123132 (2010)
  30. van den Bergh, G. D. et al. Earliest hominin occupation of Sulawesi, Indonesia. Nature 529, 208211 (2016)
  31. Heinrich, K. F. J. in Electron Probe Quantitation (eds Heinrich, K. F. J. & Newbury, D. E. ), 918 (Plenum, 1991)
  32. Jochum, K. P. et al. MPI-DING reference glasses for in situ microanalysis: New reference values for element concentrations and isotope ratios. Geochem. Geophys. Geosyst. 7, Q02008 (2006)
  33. Alloway, B. V. et al. Correspondence between glass-FT and 14C ages of silicic pyroclastic flow deposits sourced from Maninjau Caldera, west-central Sumatra. Earth Planet. Sci. Lett. 227, 121133 (2004)
  34. Jacobs, Z. & Roberts, R. G. An improved single grain OSL chronology for the sedimentary deposits from Diepkloof Rockshelter, Western Cape, South Africa. J. Archaeol. Sci. 63, 175192 (2015)
  35. Prescott, J. R. & Hutton, J. T. Cosmic ray contributions to dose rates for luminescence and ESR dating: large depths and long-term time variations. Radiat. Meas. 23, 497500 (1994)
  36. Neudorf, C. M., Roberts, R. G. & Jacobs, Z. Sources of overdispersion in a K-rich feldspar sample from north-central India: insights from De, K content and IRSL age distributions for individual grains. Radiat. Meas. 47, 696702 (2012)
  37. Neudorf, C. M. Luminescence Investigations into the Time of Final Deposition of Toba Volcanic Ash and Artefact-bearing Alluvial Sediments in the Middle Son Valley, Madhya Pradesh, India. PhD thesis, Univ. of Wollongong (2012)
  38. Huntley, D. J. & Hancock, R. G. V. The Rb contents of the K-feldspars being measured in optical dating. Anc. TL 19, 4346 (2001)
  39. Aitken, M. J. An Introduction to Optical Dating (Oxford Univ. Press, 1998)
  40. Bøtter-Jensen, L., Andersen, C. E., Duller, G. A. T. & Murray, A. S. Developments in radiation, stimulation and observation facilities in luminescence measurements. Radiat. Meas. 37, 535541 (2003)
  41. Roberts, R. G. et al. Optical dating in archaeology: thirty years in retrospect and grand challenges for the future. J. Archaeol. Sci. 56, 4160 (2015)
  42. Li, B. & Li, S.-H. Luminescence dating of K-feldspar from sediments: a protocol without anomalous fading correction. Quat. Geochronol. 6, 468479 (2011)
  43. Thiel, C. et al. Luminescence dating of the Stratzing loess profile (Austria) – testing the potential of an elevated temperature post-IR IRSL protocol. Quat. Int. 234, 2331 (2011)
  44. Li, B., Roberts, R. G. & Jacobs, Z. On the dose dependency of the bleachable and non-bleachable components of IRSL from K-feldspar: improved procedures for luminescence dating of Quaternary sediments. Quat. Geochronol. 17, 113 (2013)
  45. Huntley, D. J. & Lamothe, M. Ubiquity of anomalous fading in K-feldspars and the measurement and correction for it in optical dating. Can. J. Earth Sci. 38, 10931106 (2001)
  46. Auclair, M., Lamothe, M. & Huot, S. Measurement of anomalous fading for feldspar IRSL using SAR. Radiat. Meas. 37, 487492 (2003)
  47. Galbraith, R. F., Roberts, R. G., Laslett, G. M., Yoshida, H. & Olley, J. M. Optical dating of single and multiple grains of quartz from Jinmium rock shelter, northern Australia: Part 1, experimental design and statistical models. Archaeometry 41, 339364 (1999)
  48. Galbraith, R. F. & Roberts, R. G. Statistical aspects of equivalent dose and error calculation and display in OSL dating: an overview and some recommendations. Quat. Geochronol. 11, 127 (2012)
  49. Franklin, A. D., Prescott, J. R. & Robertson, G. B. Comparison of blue and red TL from quartz. Radiat. Meas. 32, 633639 (2000)
  50. Westaway, K. E. The red, white and blue of quartz luminescence: a comparison of De values derived for sediments from Australia and Indonesia using TL and OSL emissions. Radiat. Meas. 44, 462466 (2009)
  51. Demeter, F. et al. Anatomically modern human in Southeast Asia (Laos) by 46 ka. Proc. Natl Acad. Sci. USA 109, 1437514380 (2012)
  52. Eggins, S. M. et al. In situ U-series dating by laser-ablation multi-collector ICPMS: new prospects for Quaternary geochronology. Quat. Sci. Rev. 24, 25232538 (2005)
  53. Grün, R. et al. ESR and U-series analyses of teeth from the palaeoanthropological site of Hexian, Anhui Province, China. J. Hum. Evol. 34, 555564 (1998)
  54. Hellstrom, J. & Pickering, R. Recent advances and future prospects of the U–Th and U–Pb chronometers applicable to archaeology. J. Archaeol. Sci. 56, 3240 (2015)
  55. Zhou, H.-y., Zhao, J.-x., Wang, Q., Feng, Y.-x. & Tang, J. Speleothem-derived Asian summer monsoon variations in Central China, 54–46 ka. J. Quat. Sci. 26, 781790 (2011)
  56. Clark, T. R. et al. Discerning the timing and cause of historical mortality events in modern Porites from the Great Barrier Reef. Geochim. Cosmochim. Acta 138, 5780 (2014)
  57. Ludwig, K. R. User’s Manual for Isoplot 3.75: a Geochronological Toolkit for Microsoft Excel (Berkeley Geochron. Center, 2012)
  58. Cheng, H. et al. The half-lives of uranium-234 and thorium-230. Chem. Geol. 169, 1733 (2000)
  59. Zhao, J.-x. Yu, K.-f. & Feng, Y.-x. High-precision 238U–234U–230Th disequilibrium dating of the recent past: a review. Quat. Geochronol. 4, 423433 (2009)
  60. Lee, J.-Y. et al. A redetermination of the isotopic abundances of atmospheric Ar. Geochim. Cosmochim. Acta 70, 45074512 (2006)
  61. Wood, R. From revolution to convention: the past, present and future of radiocarbon dating. J. Archaeol. Sci. 56, 6172 (2015)
  62. Hogg, A. G. et al. SHCal13 Southern Hemisphere calibration, 0–50,000 years cal BP. Radiocarbon 55, 18891903 (2013)
  63. Bird, M. I. et al. Radiocarbon dating of “old” charcoal using a wet oxidation, stepped-combustion procedure. Radiocarbon 41, 127140 (1999)
  64. Brock, F., Higham, T. F. G., Ditchfield, P. & Bronk Ramsey, C. Current pretreatment methods for AMS radiocarbon dating at the Oxford Radiocarbon Accelerator Unit (ORAU). Radiocarbon 52, 103112 (2010)

Download references

Author information

  1. These authors contributed equally to this work.

    • Thomas Sutikna &
    • Matthew W. Tocheri
  2. Deceased.

    • Michael J. Morwood &
    • Rokus Due Awe

Affiliations

  1. Centre for Archaeological Science, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia

    • Thomas Sutikna,
    • Michael J. Morwood,
    • E. Wahyu Saptomo,
    • Jatmiko,
    • Rokus Due Awe,
    • Bo Li,
    • Brent V. Alloway,
    • Mike W. Morley,
    • Gerrit D. van den Bergh &
    • Richard G. Roberts
  2. Pusat Penelitian Arkeologi Nasional, Jakarta 12510, Indonesia

    • Thomas Sutikna,
    • E. Wahyu Saptomo,
    • Jatmiko,
    • Rokus Due Awe &
    • Sri Wasisto
  3. Department of Anthropology, Lakehead University, Thunder Bay, Ontario P7B 5E1, Canada

    • Matthew W. Tocheri
  4. Human Origins Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington DC 20013, USA

    • Matthew W. Tocheri &
    • Hanneke J. M. Meijer
  5. Traps MQ Luminescence Dating Facility, Department of Environmental Sciences, Macquarie University, Sydney, New South Wales 2109, Australia

    • Kira E. Westaway
  6. Research Centre for Human Evolution, Place, Evolution and Rock Art Heritage Unit, Griffith University, Gold Coast, Queensland 4222, Australia

    • Maxime Aubert
  7. School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia

    • Maxime Aubert &
    • Adam Brumm
  8. School of Earth Sciences, University of Queensland, Brisbane, Queensland 4072, Australia

    • Jian-xin Zhao
  9. QUADLAB, Section of Earth and Planetary System Science, Natural History Museum of Denmark, 1350 Copenhagen, Denmark

    • Michael Storey
  10. School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington 6012, New Zealand

    • Brent V. Alloway
  11. Department of Natural History, University Museum of Bergen, University of Bergen, 5007 Bergen, Norway

    • Hanneke J. M. Meijer
  12. Research Centre for Human Evolution, Environmental Futures Research Institute, Griffith University, Brisbane, Queensland 4111, Australia

    • Rainer Grün &
    • Adam Brumm
  13. Research School of Earth Sciences, Australian National University, Canberra, Australian Capital Territory 0200, Australia

    • Rainer Grün
  14. GeoQuEST Research Centre, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia

    • Anthony Dosseto
  15. Department of Anatomical Sciences, Stony Brook University Medical Center, Stony Brook, New York 11794, USA

    • William L. Jungers
  16. Association Vahatra, BP 3972, Antananarivo 101, Madagascar

    • William L. Jungers

Contributions

M.J.M., R. P. Soejono and R.G.R. conceived and coordinated the original research program at Liang Bua (2001–2004). The new excavations were planned and directed by T.S., E.W.S. and M.J.M. (2007–2009), and by T.S., M.W.T., E.W.S., J. and M.J.M. (2010–2014). T.S. led the stratigraphic analyses, with major contributions from M.W.T., S.W., M.J.M., K.E.W., R.D.A., E.W.S. and J., and additional input from M.W.M., H.J.M.M., G.D.vdB., B.V.A., A.B., W.L.J. and R.G.R. Dating analyses were conducted by B.L. and R.G.R. (IRSL), K.E.W. (TL), M.A., R.G. and A.D. (234U/230Th, bones), J.-x.Z. (234U/230Th, speleothems), and M.S. (40Ar/39Ar). B.V.A. analysed the volcanic tephra, R.D.A., H.J.M.M., G.D.vdB., M.W.T. and W.L.J. analysed the faunal remains, and J. analysed the stone artefacts. T.S., M.W.T. and R.G.R. wrote the paper, with early contributions from M.J.M. and additional input from all other authors.

Competing financial interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to:

Author details

Extended data figures and tables

Extended Data Figures

  1. Extended Data Figure 1: Stratigraphy of the excavated area near the eastern cave wall at eight stages of depositional history, with approximate ages indicated. (645 KB)

    a–h, Each panel shows the remnant deposits exposed in the 2-m-wide baulks of the following Sectors (from left to right): north VII, east VII, XI and XXIII, south XXIII and XXI, west XXI, XV and XVI, and north XVI. The pedestal deposits shown in b–d were truncated by one or more phases of erosion that resulted in an erosional surface (that is, an unconformity) that slopes steeply down towards the cave mouth (see also Supplementary Video 1). The black arrows relate to the accompanying text in each panel. The maximum depth excavated was 10.75 m in Sector VII (for example, the left two panels in h).

  2. Extended Data Figure 2: Deposits containing the remains of Homo floresiensis. (1,333 KB)

    These deposits (A) consist of multiple layers of fine-grained sediment interspersed with layers of weathered limestone and loose gravel, and are directly overlain by two tephras (T1 and T2). a, South baulk of Sector XV, near the eastern cave wall. b, West baulk of Sector XV, also showing the unconformably overlying deposits (B). c, d, North and east baulks of Sector XIX, near the cave centre.

  3. Extended Data Figure 3: The volcaniclastic deposits at Liang Bua. (764 KB)

    a, Photograph of tephras T6–T8 (north baulk of Sector XVI). b, Photograph of tephras T1–T5 (south baulk of Sector XXI). c, Bivariate plot of FeO and CaO concentrations (expressed as weight %), acquired by electron microprobe analysis of glass shards from T1 (n = 6), T3 (n = 4), T5 (n = 10) and T7 (n = 15), as well as the Youngest Toba Tuff (YTT, n = 207, ± 1σ) from northern Sumatra. d, Bivariate plot of FeO and K2O concentrations (symbols as in c). e, Bivariate plot of SiO2 and Na2O + K2O concentrations (symbols as in c). f, Isotope correlation (inverse isochron) plot for hornblende crystals from T1. The error ellipses represent individual analyses (n = 28). The ellipse on the far right-hand side was omitted from the 40Ar/39Ar age determination of 79 ± 12 kyr (at 1σ).

  4. Extended Data Figure 4: Erosional surface of the pedestal in the west baulks of Sectors XV and XVI. (687 KB)

    The dashed line marks the steeply sloping boundary between remnant deposits (T2, T1 and the underlying Homo floresiensis-bearing sediments) that comprise part of the pedestal (A) and the much younger deposits (B) that unconformably overlie the contact. a, Photograph taken at an upward angle showing the sedimentary differences between the deposits above and below the erosional boundary. b, Illustration of the erosional surface and underlying deposits shown in a.

  5. Extended Data Figure 5: Erosional surface of the pedestal near the eastern wall of the cave. (794 KB)

    a, Illustration of the erosional surface and the locations of LB1, LB4, LB6 and LB8 below the boundary (see also Fig. 3). The deposits that unconformably overlie the pedestal are shown in the south and west baulks. The stippled cube outlines the photographed area (in Sector XV) shown in b and c. Both photographs taken from above, with north towards the bottom of the page.

  6. Extended Data Figure 6: Locations of sediment samples dated in this study and TL data for quartz grains from Liang Bua. (332 KB)

    a, Stratigraphy of the excavated area near the eastern cave wall (Sector baulks as in Extended Data Fig. 1) with TL samples indicated by red circles, IRSL samples by blue circles and the 40Ar/39Ar sample by a yellow square. Also shown are the TL and IRSL sample codes and the locations of hominin remains LB1 and LB6. b, Representative isothermal (260 °C) TL decay curves for the natural (black line) and test dose (grey line) signals from sample LB08-15-3. c, d, Regenerated TL dose–response curves for one pair of Aliquots A and B of sample LB08-15-3, respectively; the equivalent dose (De) is estimated by projecting the natural signal (red square) on to the dose–response curve fitted to the regenerated signals (blue diamonds). e, Radial plot47, 48 of De values for Aliquot A (n = 12) of sample LB08-15-3; the grey band is centred on the weighted mean De calculated using the central age model. f, Radial plot of the corresponding De values for Aliquot B (n = 12) of the same sample. The grey band is centred on the central age model estimate, with the two high-De outliers omitted. The red line intersects the right-hand axis at the De calculated by fitting the minimum age model47, 48 to all 12 values. g, h, Radial plots of De values for Aliquots A and B of sample LB12-23-1 (symbols as in e and f).

  7. Extended Data Figure 7: IRSL data and potassium (K) concentrations for feldspar grains from Liang Bua. (267 KB)

    a, Representative IRSL (50 °C) and multiple elevated temperature (100–250 °C) post-infrared IRSL (pIRIR) decay curves for a single aliquot of sample LB12-OSL1. b, IRSL (50 °C) and pIRIR (290 °C) decay curves for a different aliquot of LB12-OSL1. c, Regenerated pIRIR (290 °C) dose–response curve for the aliquot shown in b; the equivalent dose (De) is estimated by projecting the natural signal (red square) on to the dose–response curve fitted to the regenerated signals (blue diamonds). d–j, Radial plots of IRSL ages (corrected for residual dose and anomalous fading) for single aliquots of each sample: d, LB12-OSL1; e, LB12-OSL2; f, LB12-OSL3; g, LB12-OSL4; h, LB12-OSL5; i, LB12-OSL6; and j, LB12-OSL7. IRSL ages were also obtained for single grains of samples LB12-OSL3 and LB12-OSL4, and are shown as open triangles in f and g. The grey bands in each plot are centred on the weighted mean ages calculated using the central age model. k, l, Radial plots of IRSL ages (corrected as for d–j) for samples LBS7-40a and LBS7-42a, respectively; single aliquots are shown as filled circles and single grains as open triangles. The upper and lower red lines intersect the right-hand axis at the maximum and minimum single-grain ages, respectively. m, Distribution of pIRIR intensities from 28 individual grains of feldspar from sample LB12-OSL3 that had been given a regenerative dose of 80 Gy. The relative contribution of each grain to the total (cumulative) pIRIR light sum is plotted as a function of K concentration (measured by wavelength-dispersive X-ray spectroscopy); note the reversed scale on the x-axis. n, Cumulative pIRIR light sum for the same 28 grains as shown in m, plotted as a function of grains ranked by K concentration (which decreases from left to right).

  8. Extended Data Figure 8: Laser-ablation uranium-series analyses of hominin bone fragments from various Sectors and spits (depth intervals), and their modelled ages. (916 KB)

    a, Modern human femur (132A/LB/27D/03) from Sector IV, spit 27 (265–275 cm). b, Homo floresiensis ulna (LB1/52) from Sector XI, spit 58A (575–585 cm). c, H. floresiensis ulna (LB2/1) from Sector IV, spit 42D (415–425 cm). d, H. floresiensis ulna (LB6/3) from Sector XI, spit 51 (505–515 cm). Each laser spot is 265 μm in diameter and the age errors are at 2σ.

  9. Extended Data Figure 9: Laser-ablation uranium-series analyses of bone fragments of Stegodon florensis insularis from various spits (depth intervals) in Sector XI, and their modelled ages. (618 KB)

    a, U-s-01/LB/XI/32/04, spit 32 (315–325 cm). b, U-s-02/LB/XI/45/04, spit 45 (445–455 cm). c, U-s-03/LB/XI/47/04, spit 47 (465–475 cm). d, U-s-04/LB/XI/49/04, spit 49 (485–495 cm). e, U-s-05/LB/XI/51/04, spit 51 (505–515 cm). f, U-s-06/LB/XI/52/04, spit 52 (515–525 cm). g, U-s-07/LB/XI/65/04, spit 65 (645–655 cm). h, U-s-08/LB/XI/65B/04, spit 65B (645–655 cm). Each laser spot is 265 μm in diameter and the age errors are at 2σ.

  10. Extended Data Figure 10: Deposits stratigraphically above the unconformity in Sector XVI and displaced slab of deposit in Sector XXII. (1,202 KB)

    a, The north baulk (~2 m wide) of Sector XVI. b, Excavated floors (white arrow points north) of spits 61–63 (615–635 cm depth); the field of view is ~1.6 m in width. The stippled box in a indicates the floor of spit 63 in b, where fragments of T1 (+) are visible in spit 63, and fragments of T3 (*) and T1 are concentrated in the band just above the label for spit 61. Eroded fragments (between about 1 cm and 60 cm in size) of T1, T2 and T3 have been consistently recovered from deposits unconformably overlying the erosional surface of the pedestal, indicating reworking of the pedestal deposits before ~13 kyr cal. bp. c, Photograph of the west baulk and parts of the south and north baulks (at left and right, respectively) of Sector XXII showing a displaced slab of deposit that contains intact portions of the uppermost part of T3 (arrow) and the overlying layers, up to and including the flowstone (fs) that caps T5. The stratigraphic position of the slab beneath T7 and T8 indicates that it broke away from its original location, slightly to the south, and slid down the steeply sloping erosional surface before ~13 kyr cal. bp. Also shown are the Homo floresiensis-bearing deposits (A) and the unconformably overlying deposits (B), which include eroded fragments of T1 (+), T2 (#) and T3 (*). d, Illustration of the west baulk of Sector XXII, as shown in c.

Supplementary information

Video

  1. Video 1: Animated summary of the stratigraphy and chronology of the Liang Bua depositional sequence. (29.04 MB, Download)
    Animated summary of the stratigraphy and chronology of the Liang Bua depositional sequence.

PDF files

  1. Supplementary Information (995 KB)

    This file contains Supplementary Information sections 1-6 which contain a Supplementary Discussion and Supplementary Tables 1-8 – see contents page for details.

Additional data