Cultural innovation and megafauna interaction in the early settlement of arid Australia

Abstract

Elucidating the material culture of early people in arid Australia and the nature of their environmental interactions is essential for understanding the adaptability of populations and the potential causes of megafaunal extinctions 50–40 thousand years ago (ka). Humans colonized the continent by 50 ka1,2, but an apparent lack of cultural innovations compared to people in Europe and Africa3,4 has been deemed a barrier to early settlement in the extensive arid zone2,3. Here we present evidence from Warratyi rock shelter in the southern interior that shows that humans occupied arid Australia by around 49 ka, 10 thousand years (kyr) earlier than previously reported2. The site preserves the only reliably dated, stratified evidence of extinct Australian megafauna5,6, including the giant marsupial Diprotodon optatum, alongside artefacts more than 46 kyr old. We also report on the earliest-known use of ochre in Australia and Southeast Asia (at or before 49–46 ka), gypsum pigment (40–33 ka), bone tools (40–38 ka), hafted tools (38–35 ka), and backed artefacts (30–24 ka), each up to 10 kyr older than any other known occurrence7,8. Thus, our evidence shows that people not only settled in the arid interior within a few millennia of entering the continent9, but also developed key technologies much earlier than previously recorded for Australia and Southeast Asia8.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Site distribution map showing archaeological and megafaunal sites.
Figure 2: Main chrono–stratigraphic and archaeological features found in Warratyi rock shelter.
Figure 3: Earliest bone point.

References

  1. 1

    Veth, P. & O’Connor, S. in Cambridge History of Australia, Volume 1 Colonial Australia (eds Bashford, A. & Macintyre, S. ) 1–34 (Cambridge Univ. Press, 2013)

  2. 2

    Allen, J. & O’Connell, J. Both half right: updating the evidence for dating first human arrivals in Sahul. Aust. Archaeol. 79, 86–108 (2014)

    Article  Google Scholar 

  3. 3

    Mellars, P. Going east: new genetic and archaeological perspectives on the modern human colonization of Eurasia. Science 313, 796–800 (2006)

    ADS  CAS  PubMed  Article  Google Scholar 

  4. 4

    Boivin, N., Fuller, D. Q., Dennel, R., Allaby, R. & Petraglia, M. D. Human dispersal across diverse environments of Asia during the Upper Pleistocene. Quat. Int. 300, 32–47 (2013)

    Article  Google Scholar 

  5. 5

    Roberts, R. G. et al. New ages for the last Australian megafauna: continent-wide extinction about 46,000 years ago. Science 292, 1888–1892 (2001)

    ADS  CAS  PubMed  Article  Google Scholar 

  6. 6

    Grellet-Tinner, G., Spooner, N. A. & Worthy, T. H. Is the ‘Genyornis’ egg of mihirung or another extinct bird from the Australian dreamtime? Quat. Sci. Rev. 133, 147–164 (2016)

    ADS  Article  Google Scholar 

  7. 7

    Attenbrow, V., Robertson, G. & Hiscock, P. The changing abundance of backed artefacts in south-eastern Australia: a response to Holocene climate change? J. Archaeol. Sci. 36, 2765–2770 (2009)

    Article  Google Scholar 

  8. 8

    Habgood, P. J. & Franklin, N. R. The revolution that didn’t arrive: a review of Pleistocene Sahul. J. Hum. Evol. 55, 187–222 (2008)

    PubMed  Article  Google Scholar 

  9. 9

    Hiscock, P. & Wallis, L. in Desert Peoples: Archaeological Perspectives (eds Veth, P., Smith, M. & Hiscock, P. ) 34–57 (Blackwell Publishers, 2005)

  10. 10

    Smith, M. The Archaeology of Australia’s Deserts (Cambridge Univ. Press, 2013) 185–187

  11. 11

    Slack, M. J., Fullagar, R. L. K., Field, J. H. & Border, A. New Pleistocene ages for backed artefact technology in Australia. Archaeol. in Oceania 39, 131–137 (2004)

    Article  Google Scholar 

  12. 12

    Mulvaney, D. J. & Kamminga, J. The Prehistory of Australia (Allen & Unwin Pty Ltd, 1999)

  13. 13

    Barton, H. M., Piper, P. J., Rabett, R. & Reeds, I. Composite hunting technologies from the terminal Pleistocene and early Holocene, Niah Cave Borneo. J. Archaeol. Sci. 36, 1708–1714 (2009)

    Article  Google Scholar 

  14. 14

    O’Connor, S. & Frankhauser, B. in Histories of Old Ages: Essays in Honour of Rhys Jones (eds Anderson, A., Lilley, I. & O’Connor, S. ) 287–300 (Pandanus Books, Research School of Pacific and Asian Studies, Australian National Univ., 2001)

  15. 15

    Aubert, M. et al. Pleistocene cave art from Sulawesi, Indonesia. Nature 514, 223–227 (2014)

    ADS  CAS  PubMed  PubMed Central  Article  Google Scholar 

  16. 16

    Webb, C. & Allen, J. A functional analysis of Pleistocene bone tools from two sites in southwest Tasmania. Archaeol. in Oceania 25, 75–78 (1990)

    Article  Google Scholar 

  17. 17

    O’Connor, S., Robertson, G. & Aplin, K. P. Are osseous artefacts a window to perishable material culture? Implications of an unusually complex bone tool from the Late Pleistocene of East Timor. J. Hum. Evol. 67, 108–119 (2014)

    PubMed  Article  Google Scholar 

  18. 18

    Rabett, J. R. The early exploitation of South-east Asian mangroves: bone technology from caves and open sites. Asian Perspect. 44, 154–179 (2005)

    Article  Google Scholar 

  19. 19

    Cosgrove, R. Forty two degrees south: the archaeology of Late Pleistocene Tasmania. J. World Prehist. 13, 357–402 (1999)

    Article  Google Scholar 

  20. 20

    Dortch, C. E. Devil’s Lair, A Study in Prehistory (Western Australian Museum, 1984)

  21. 21

    Dortch, C. E. & Dortch, J. Review of Devil’s Lair artefact classification and radiocarbon chronology. Aust. Archaeol. 43, 28–32 (1996)

    Article  Google Scholar 

  22. 22

    Barnosky, A. D., Koch, P. L., Feranec, R. S., Wing, S. L. & Shabel, A. B. Assessing the causes of late Pleistocene extinctions on the continents. Science 306, 70–75 (2004)

    ADS  CAS  PubMed  PubMed Central  Article  Google Scholar 

  23. 23

    Field, J. H., Wroe, S., Trueman, C. N., Garvey, J. & Wyatt-Spratt, S. Looking for the archaeological signature in Australian megafaunal extinctions. Quat. Int. 285, 76–88 (2013)

    Article  Google Scholar 

  24. 24

    Wroe, S. et al. Climate change frames debate over the extinction of megafauna in Sahul (Pleistocene Australia–New Guinea). Proc. Natl Acad. Sci. USA 110, 8777–8781 (2013)

    ADS  CAS  PubMed  Article  Google Scholar 

  25. 25

    Miller, G. H. et al. Pleistocene extinction of Genyornis newtoni: human impact on australian megafauna. Science 283, 205–208 (1999)

    CAS  PubMed  Article  Google Scholar 

  26. 26

    Brook, B. W. et al. Lack of chronological support for stepwise prehuman extinctions of Australian megafauna. Proc. Natl Acad. Sci. USA 110, E3368 (2013)

    CAS  PubMed  Article  Google Scholar 

  27. 27

    Cohen, T. et al. Hydrological transformation coincided with megafaunal extinction in central Australia. Geology 43, 195–198 (2015)

    ADS  Article  Google Scholar 

  28. 28

    Grün, R. et al. ESR and U-series analyses of faunal material from Cuddie Springs, NSW, Australia: implications for the timing of the extinction of the Australian megafauna. Quat. Sci. Rev. 29, 596–610 (2010)

    ADS  MathSciNet  Article  Google Scholar 

  29. 29

    Balme, J., Davidson, I., McDonald, J., Stern, N. & Veth, P. Symbolic behaviour and the peopling of the southern arc route to Australia. Quat. Int. 202, 59–68 (2009)

    Article  Google Scholar 

  30. 30

    Larson, M. L. & Kornfeld, M. Chipped stone nodules: theory, method, and examples. Lithic Technol. 22, 4–18 (1997)

    Article  Google Scholar 

  31. 31

    Villa, P. Conjoinable pieces and site formation processes. Am. Antiq. 47, 276–290 (1982)

    Article  Google Scholar 

  32. 32

    Laughlin, J. P. & Kelly, R. L. Experimental analysis of the practical limits of lithic refitting. J. Archaeol. Sci. 37, 427–433 (2010)

    Article  Google Scholar 

  33. 33

    Aitken, M. J. An Introduction to Optical Dating: the Dating of Quaternary Sediments by the Use of Photon-stimulated Luminescence (Oxford Univ. Press 1998)

  34. 34

    Murray, A. S. & Roberts, R. G. Determining the burial time of single grains of quartz using optically stimulated luminescence. Earth Planet. Sci. Lett. 152, 163–180 (1997)

    ADS  CAS  Article  Google Scholar 

  35. 35

    Bøtter-Jensen, L., Bulur, E., Duller, G. A. T. & Murray, A. S. Advances in luminescence instrument systems. Radiat. Meas. 32, 523–528 (2000)

    Article  Google Scholar 

  36. 36

    Olley, J. M., Pietsch, T. & Roberts, R. G. Optical dating of Holocene sediments from a variety of geomorphic settings using single grains of quartz. Geomorphology 60, 337–358 (2004)

    ADS  Article  Google Scholar 

  37. 37

    Arnold, L. J., Bailey, R. M. & Tucker, G. E. Statistical treatment of fluvial dose distributions from southern Colorado arroyo deposits. Quat. Geochronol. 2, 162–167 (2007)

    Article  Google Scholar 

  38. 38

    Arnold, L. J., Demuro, M. & Navazo Ruiz, M. Empirical insights into multi-grain averaging effects from ‘pseudo’ single-grain OSL measurements. Radiat. Meas. 47, 652–658 (2012)

    CAS  Article  Google Scholar 

  39. 39

    Demuro, M. et al. Optically stimulated luminescence dating of single and multiple grains of quartz from perennially frozen loess in western Yukon territory, Canada: comparison with radiocarbon chronologies for the late Pleistocene Dawson tephra. Quat. Geochronol. 3, 346–364 (2008)

    Article  Google Scholar 

  40. 40

    Demuro, M., Arnold, L. J., Froese, D. G. & Roberts, R. G. OSL dating of loess deposits bracketing Sheep Creek tephra beds, northwest Canada: dim and problematic single-grain OSL characteristics and their effect on multi-grain age estimates. Quat. Geochronol. 15, 67–87 (2013)

    Article  Google Scholar 

  41. 41

    Wang, X. L., Wintle, A. G. & Lu, Y. C. Thermally transferred luminescence in fine-grained quartz from Chinese loess: basic observations. Radiat. Meas. 41, 649–658 (2006)

    CAS  Article  Google Scholar 

  42. 42

    Arsuaga, J. L. et al. Neandertal roots: cranial and chronological evidence from Sima de los Huesos. Science 344, 1358–1363 (2014)

    ADS  CAS  PubMed  PubMed Central  Article  Google Scholar 

  43. 43

    Demuro, M., Arnold, L. J., Parés, J. M. & Sala, R. Extended-range luminescence chronologies suggest potentially complex bone accumulation histories at the Early-to-Middle Pleistocene palaeontological site of Huéscar-1 (Guadix-Baza basin, Spain). Quat. Int. 389, 191–212 (2015)

    Article  Google Scholar 

  44. 44

    Arnold, L. J. et al. Luminescence dating and palaeomagnetic age constraint on hominins from Sima de los Huesos, Atapuerca, Spain. J. Hum. Evol. 67, 85–107 (2014)

    PubMed  Article  Google Scholar 

  45. 45

    Demuro, M. et al. New luminescence ages for the Galería Complex archaeological site: resolving chronological uncertainties on the acheulean record of the Sierra de Atapuerca, northern Spain. PLoS One 9, e110169 (2014)

    ADS  PubMed  PubMed Central  Article  CAS  Google Scholar 

  46. 46

    Stevens, T., Buylaert, J.-P. & Murray, A. S. Towards development of a broadly-applicable SAR TT-OSL dating protocol for quartz. Radiat. Meas. 44, 639–645 (2009)

    CAS  Article  Google Scholar 

  47. 47

    Tsukamoto, S., Duller, G. A. T. & Wintle, A. G. Characteristics of thermally transferred optically stimulated luminescence (TT-OSL) in quartz and its potential for dating sediments. Radiat. Meas. 43, 1204–1218 (2008)

    CAS  Article  Google Scholar 

  48. 48

    Galbraith, R. F. A note on the variance of a background-corrected OSL count. Ancient TL 20, 49–51 (2002)

    Google Scholar 

  49. 49

    Duller, G. A. T. Assessing the error on equivalent dose estimates derived from single aliquot regenerative dose measurements. Ancient TL 25, 15–24 (2007)

    CAS  Google Scholar 

  50. 50

    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, 497–500 (1994)

    CAS  Article  Google Scholar 

  51. 51

    Mejdahl, V. Internal radioactivity in quartz and feldspar grains. Ancient TL 5, 10–17 (1987)

    Google Scholar 

  52. 52

    Bowler, J. M. et al. New ages for human occupation and climatic change at Lake Mungo, Australia. Nature 421, 837–840 (2003)

    ADS  CAS  PubMed  Article  Google Scholar 

  53. 53

    Jacobs, Z., Duller, G. A. T. & Wintle, A. G. Interpretation of single-grain De distributions and calculation of De . Radiat. Meas. 41, 264–277 (2006)

    CAS  Article  Google Scholar 

  54. 54

    Pawley, S. M. et al. Age limits on Middle Pleistocene glacial sediments from OSL dating, north Norfolk, UK. Quat. Sci. Rev. 27, 1363–1377 (2008)

    ADS  Article  Google Scholar 

  55. 55

    Questiaux, D. Optical dating of loess: comparisons between different grain size fractions for infrared and green excited wavelengths. Nucl. Tracks Radiat. Meas. 18, 133–139 (1991)

    CAS  Article  Google Scholar 

  56. 56

    Rees-Jones, J. Optical dating of young sediments using fine-grain quartz. Ancient TL 13, 9–14 (1995)

    Google Scholar 

  57. 57

    Rees-Jones, J. & Tite, M. S. Optical dating results for British archaeological sediments. Archaeometry 39, 177–187 (1997)

    Article  Google Scholar 

  58. 58

    Guérin, G., Mercier,N. & Adamiec, G. Dose-rate conversion factors: update. Ancient TL 29, 5–8 (2011)

    Google Scholar 

  59. 59

    Mejdahl, V. Thermoluminescence dating: beta-dose attenuation in quartz grains. Archaeometry 21, 61–72 (1979)

    CAS  Article  Google Scholar 

  60. 60

    Brennan, B. J. Beta doses to spherical grains. Radiat. Meas. 37, 299–303 (2003)

    CAS  Article  Google Scholar 

  61. 61

    Stuiver, M. & Polach, H. A. Reporting of 14C data. Radiocarbon 19, 355–363 (1977)

    Article  Google Scholar 

  62. 62

    Hogg, A. G. et al. SHCal13 Southern Hemisphere calibration 0–50,000 years cal bp. Radiocarbon 55, 1889–1903 (2013)

    CAS  Article  Google Scholar 

  63. 63

    Bronk Ramsey, C. Radiocarbon calibration and analysis of stratigraphy: the OxCal program. Radiocarbon 37, 425–430 (1995)

    CAS  Article  Google Scholar 

  64. 64

    Macken, A. C., Staff, R. A. & Reed, E. H. Bayesian age-depth modelling of Late Quaternary deposits from Wet and Blanche Caves, Naracoorte, South Australia: a framework for comparative faunal analyses. Quat. Geochronol. 17, 26–43 (2013)

    Article  Google Scholar 

  65. 65

    O’Connell, J. F. & Allen, J. The process, biotic impact, and global implications of the human colonization of Sahul about 47,000 years ago. J. Archaeol. Sci. 56, 73–84 (2015)

    Article  Google Scholar 

  66. 66

    Bronk Ramsey, C. Dealing with offsets and outliers in radiocarbon dating. Radiocarbon 51, 1023–1045 (2009)

    Article  Google Scholar 

  67. 67

    Stephenson, B. A modified Picro-Sirius Red (PSR) staining procedure with polarization microscopy for identifying collagen in archaeological residues. J. Archaeol. Sci. 61, 235–243 (2015)

    CAS  Article  Google Scholar 

Download references

Acknowledgements

The fieldwork was undertaken with the approval of Adnyamathanha Traditional Lands Association (ATLA) and the South Australian Department of Aboriginal Affairs and Reconciliation. We thank for their contributions: A. Coulthard who participated in the fieldwork; R. Frank for his support both in the field and with drawing site maps; field assistants L. Foley and S. Adams; R. Cosgrove provided faunal advice; G. Robertson assisted with residue laboratory work; C. Brown assisted with graphic design, N. Bonney provided botanical advice; M. Raven and J. Webb carried out analyses of ochres; G. Medlin provided faunal advice; B. Barker provided botanical advice; P. Toms provided access to single grain OSL dating assessment; F. Williams for assistance in fieldwork and sample collection for optical dating; A. Couzens, W. Handley and G. Gully for their assistance with micro-CT imaging and photography of megafaunal specimens; and P. Veth, P. Hiscock, B. Cundy, W. Shawcross, S. Webb, J. Magee and D. Witter for critical feedback on the manuscript. This research was supported by Alinta Energy who provided financial support for fieldwork carried out in May 2013. L.A. and G.P. were supported by Australian Research Council Future Fellowship Grants FT130100195 and FT130101728, respectively. V.L. and Centre for Accelerator Science at ANSTO, acknowledge the support of the Australian Government through the National Collaborative Research Infrastructure Strategy (NCRIS). FWS is who - they did the drawing of the lithics and ought to be here.

Author information

Affiliations

Authors

Contributions

G.H. conceived the project, supervised fieldwork, undertook data collection and analysis. L.A. provided chronological assessment for sediments and undertook the Bayesian age modelling. G.P. and T.W. identified megafaunal remains. D.Q. prepared chronological samples. N.S. advised on the results of chronological assessments. V.L. assisted with radiocarbon dating issues. E.F. provided fieldwork support and assisted in the analysis of stone artefact material. B.S. analysed and reported on stone artefact residues. V.C. and C.C. provided cultural advice and logistical support. C.C., S.W. and D.J assisted with fieldwork. G.H., P.M., L.A., G.P. and T.W. wrote the paper.

Corresponding author

Correspondence to Giles Hamm.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Figure 1 Warratyi rock shelter, site location, site plan and excavation strategy.

a, Warratyi rock shelter above a dry creek bed, looking west at the main ridge profile and rocky bench at the front of the shelter. b, Plan of Warratyi rock shelter showing layout of excavation. Excavation squares (4D/4C and 2C/2B) have a surface area of 1 m2. Drawing by R. Frank. c, Warratyi rock shelter excavation plan showing the layout of the excavation squares and 25 cm × 25 cm (A–D) quadrat units within each square.

Extended Data Figure 2 Excavation profiles and section drawings of Warratyi rock shelter square 2C.

a, Profile of the west face of square 2C from the surface to the weathered bedrock on the floor of the shelter. Several charcoal concentrations and small lenticular features of ash and charcoal were interpreted as hearths. Roof fall flakes occur throughout and the only evidence of burrowing is the small, darker grey area on the left edge, which was traced across the excavation and identified as a rabbit burrow. This material was excavated separately to limit contamination of the main deposit. The numbers shown here denote the features shown in the profile drawing in b. The scale bar is marked with 20 cm units. b, Stratigraphic profile drawing of square 2C showing general stratigraphic features with feature descriptions and stratigraphic unit descriptions. c, Legend for stratigraphic profile drawing of square 2C. The scale bar is marked with 20 cm units.

Extended Data Figure 3 Excavation profiles and section drawings of Warratyi rock shelter squares 4C and 4D.

a, Profile of the north face of square 4D and part of 4C (right of centre). All stratigraphic units are visible. A cross-section of the identified rabbit burrow is prominent in 4C; this disturbance, however, is limited and the burrow fill was excavated separately. Continuous concentrations of white pigment (9: gypsum spheres and pellets) are visible on either side of the burrow, attesting to the stratigraphic integrity of the surrounding deposits. The numbers shown here correspond to the features noted in b and c, drawing and legend respectively. The scale bar is marked with 20 cm units. b, Profile drawing of excavated squares 4C and 4D, depicting the stratigraphy visible in a. A rabbit burrow is located in the centre of the drawing in square 4C. Vertical and horizontal scales are equal. c, Legend for stratigraphic profile drawing of squares 4C and 4D.

Extended Data Figure 4 Graphical representation of the size of stone artefacts and distribution of raw materials in Warratyi rock shelter.

a, Distribution of lengths for in situ >1 cm artefacts found at Warratyi rock shelter. Blue line, maximum length; grey line, mean; orange, minimum length. b, Distribution of raw material types for stone artefacts <1 cm in length by spit at Warratyi rock shelter. Orange, chalcedony; green, quartz; brown, silcrete; yellow, chert.

Extended Data Figure 5 A sample of the stone artefacts found in Warratyi rock shelter.

Drawing of select Warratyi stone artefacts.1, Adze flake, chalcedony, square 2C, spit 4. 2, Adze flake, chalcedony, square 2C, spit 5, retains patches of resinous adhesive. 3, Geometric, backed artefact, silcrete, square 2B, spit 5. 4, Geometric, backed artefact, silcrete, square 2B, spit 5. 5, Geometric, backed artefact, silcrete, square 2B, spit 5. 6, Flake with backing on one edge, silcrete, square 2B, spit 5. 7, Core, rolled quartz pebble, square 4C, spit 9. 8, Core, rolled quartz pebble, square 4C, spit 15. 9, Retouched, quartzite flake, square 2C, spit 15.

Extended Data Figure 6 Single-grain OSL dose-recovery and single-grain OSL and TT-OSL De distribution results for Warratyi rock shelter

A, Single-grain OSL and TT-OSL dose-recovery test results. Aa, Radial plot showing the recovered to given dose ratios obtained for individual quartz grains of ESR-5 using the OSL SAR procedure (Supplementary Table 3). The natural OSL signals of these grains were first optically bleached with two 1,000-s blue LED illuminations at ambient temperature, each separated by a 10,000 s pause. The grey shaded region on the radial plot is centred on the administered dose for each grain (sample average = 130 Gy). Ab, Radial plot showing the dose-recovery test (natural + dosed) De values obtained for individual quartz grains of ESR-7 using the TT-OSL SAR procedure (Supplementary Table 3). The single-grain natural signals were not bleached during the TT-OSL dose-recovery test. Instead, a known dose of similar magnitude to the expected De was added on top of the natural signals. B, Representative OSL or TT-OSL decay and dose–response curves for individual quartz grains from Warratyi rock shelter. Ba, Quartz grain from sample ERS-6 with an average OSL signal (Tn ≈ 800 counts per 0.17 s). Bb, Quartz grain from sample ERS-6 with a relatively bright OSL signal (Tn ≈ 5,000 counts per 0.17 s). Bc, Quartz grain from sample ERS-7 with an average TT-OSL signal (Tn ≈ 100 counts per 0.17 s). Bd, Quartz grain from sample ERS-7 with a relatively bright TT-OSL signal (Tn ≈ 200 counts per 0.17 s). In the insets, open circles denote the sensitivity-corrected natural OSL or TT-OSL signals, and filled circles denote the sensitivity-corrected regenerated OSL or TT-OSL signals. D0 values characterize the rate of signal saturation with respect to administered dose and equate to the dose value for which the saturating exponential dose–response curve slope is 1/e (or ~0.37) of its initial value. C, Single-grain OSL and TT-OSL De distributions for the Warratyi rock shelter samples. Grey bands are centred on the De values derived using either the central age model (samples ERS-4 (Cc), ERS-5 (Ce), ERS-7(Cg)), or the finite-mixture model (samples ERS-1 (Ca), ERS-2 (Cb), ERS-3 (Cc), ERS-6(Cf)). Percentage of grains associated with each finite-mixture model component (kn) are shown in Ca, Cb, Cc and Cf.

Extended Data Figure 7 Bayesian modelling results for Warratyi rock shelter.

a, Bayesian modelling of optical-dating and 14C results from Warratyi rock shelter. The prior age distributions for the dating samples (likelihoods) are shown as light blue probability density functions (PDFs). The modelled posterior distributions for the dating sample and stratigraphic unit boundaries are shown as dark blue and grey PDFs, respectively. Optical dating and 14C ages are shown on a calendar year timescale and both are expressed in years before 1950 ad. The 14C data were input into the model as conventional ages and were subsequently calibrated using the SHCal13 curve64 as part of the modelling procedure. The white circles and associated error bars represent the mean ages and 1 standard error uncertainty ranges of the PDFs. The 68.2% and 95.4% ranges of the highest posterior probabilities are indicated by the horizontal bars underneath the PDFs. b, Bayesian-modelled durations of the stratigraphic units at Warratyi rock shelter. The PDFs have been calculated from the modelled posterior probabilities of the upper and lower boundaries of each stratigraphic unit (shown as grey PDFs in plot a using the difference query function in OxCal v4.2.4.

Extended Data Figure 8 Distribution of resin and red ochre material on stone artefacts and gypsum analysis.

Aa, Resin adhering to the medial arris ridge that runs the length of the dorsal surface at 215× magnification in plane (pp, left) and cross polarized (xp, right). Scale bar, 0.2 mm. Ab, Resin with carbonized inclusions and associated hafting polish 500× darkfield. Scale bar, 20 μm. Ac, Ocre grains within the worked margin; 50× darkfield. Scale bar, 100 μm. Ad, Worked ochre grains; 500× brightfield cross polarized. Scale bar, 20.0 μm. Ba, Spheres of gypsum lying in situ within excavated square 4C, Warratyi rock shelter. Bb, Scanning electron microscope image of gypsum from Warratyi rock shelter. The sample consisted of very fine-grained clear gypsum-cleavage plates, mostly sub-equidimensional to slightly tabular and 5–10 μm across. There are occasional larger tabular–acicular (needle-like) fragments up to 100 μm long. Scattered through the gypsum are well-rounded, sub-spherical silt-sized grains of quartz 50–75 μm across, generally reddish in colour. Scale bar, 1 μm.

Extended Data Figure 9 Analysis of putative Genyornis oological eggshell material.

A, Scanning electron micrographs of sample 1 from square 4C, quadrat B, spit 18. Aa, view of a fresh broken edge showing a smooth eroded-out surface (upper), a section through a pore canal; Ab, detail of the pore canal opening showing the material filling pore; Ac, detail of the inner layer 1 and smooth inner surface of the shell showing that it is slightly eroded, so that the tips of the mammillary cones of layer 1 are lost; Ad, outer surface of the shell showing an elongated pair of pore canal openings occluded by material; Ae, outer surface of the shell showing the rounded eroded edge of the fragment; Af, outer surface of the shell and another opening to a pore canal showing its elongated nature and occlusion by material. B, Scanning electron micrograph views of an eggshell of Anseranas semipalmata (sample from the South Australia Museum B.14591) showing the cross-section on the left and a detail of the accessory layer on the right. Note that the accessory layer comprises an amorphous mass of similar sized spheres, a structure that typifies the accessory layer of many galloanseres, including that of putative Genyornis material. C, Element-profile plot across the pore aperture shown in Ab. The sides of the pore are at approximately 40 and 90 μm on the x axis and on either side the profile reflects the dominant CaCO3 nature of eggshell. Within the pore, elevated levels of iron (Fe), silica (Si) and aluminium (Al) are present.

Extended Data Figure 10 Megafaunal bone evidence of D. optatum.

A, Comparison between the Diprotodon bone (EMU RS-6737-7754) from Warratyi rock shelter and juvenile radius specimens of D. optatum from the South Australian Museum (SAMA P51340–P51342). Aa, EMU RS-6737-7754 in anterior view. Ab, View of the broken distal end of EMU RS-6737-7754. Ac, EMU RS-6737-7754 in posterior view. Ad, View of the broken proximal end of EMU RS-6737-7754. Ae, View of the broken distal end of SAMA P51340. Af, SAMA P51340 in posterior view. Ag, View of the broken proximal end of SAMA P51341. Ah, View of the broken distal end of SAMA P51341. Ai, SAMA P51341 in posterior view. Aj, View of the broken proximal end of SAMA P51340. Ak, SAMA P51342 in posterior view. The silhouette represents the approximate corresponding position for EMU RS-6737-7754. Scale bars, 20 mm. The top scale bar is for panels AaAj; the bottom scale bar is for panel Ak. B, Micro-computed tomographic images comparing EMU RS-6737-7754 with a juvenile radius specimen of D. optatum. Ba, Isosurface rendering of EMU RS-6737-7754 showing the position of a more proximal cross-section. Bb, Isosurface rendering of EMU RS-6737-7754 showing the position of a more distal cross-section. Bc, Isosurface rendering of SAMA P51341 showing the position of the cross-section. Bd, More proximal cross-section of EMU RS-6737-7754 (as shown in Ba). Be, More distal cross-section of EMU RS-6737-7754 (as shown in Bb). Bf, Cross-section of SAMA P51341 (as shown in Bc). Bg, Longitudinal-section of EMU RS-6737-7754. Bh, Longitudinal-section of a portion of SAMA P51341. Scale bars, 20 mm. C, Taphonomic markings on the surface of EMU RS-6737-7754.

Related audio

Reporter Shamini Bundell talks to Giles Hamm about Australia’s oldest human artefacts.

Supplementary information

Supplementary Information

This file contains Supplementary Text and Data, Supplementary Tables 1-15 and additional references. (PDF 2079 kb)

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Hamm, G., Mitchell, P., Arnold, L. et al. Cultural innovation and megafauna interaction in the early settlement of arid Australia. Nature 539, 280–283 (2016). https://doi.org/10.1038/nature20125

Download citation

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.