Letter | Published:

Implications of new early Homo fossils from Ileret, east of Lake Turkana, Kenya

Nature volume 448, pages 688691 (09 August 2007) | Download Citation


Sites in eastern Africa have shed light on the emergence and early evolution of the genus Homo1,2,3,4,5,6. The best known early hominin species, H. habilis and H. erectus, have often been interpreted as time-successive segments of a single anagenetic evolutionary lineage3,7,8,9,10. The case for this was strengthened by the discovery of small early Pleistocene hominin crania from Dmanisi in Georgia that apparently provide evidence of morphological continuity between the two taxa11,12. Here we describe two new cranial fossils from the Koobi Fora Formation, east of Lake Turkana in Kenya, that have bearing on the relationship between species of early Homo. A partial maxilla assigned to H. habilis reliably demonstrates that this species survived until later than previously recognized, making an anagenetic relationship with H. erectus unlikely. The discovery of a particularly small calvaria of H. erectus indicates that this taxon overlapped in size with H. habilis, and may have shown marked sexual dimorphism. The new fossils confirm the distinctiveness of H. habilis and H. erectus, independently of overall cranial size, and suggest that these two early taxa were living broadly sympatrically in the same lake basin for almost half a million years.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1.

    & Koobi Fora Research Project Vol. 1 The Fossil Hominids and an Introduction to their Context 1968–1974 (Clarendon, Oxford, 1978)

  2. 2.

    Koobi Fora Research Project Vol. 4 Hominid Cranial Remains (Clarendon, Oxford, 1991)

  3. 3.

    Olduvai Gorge Vol. 4 The Skulls and Endocasts of Homo habilis (Cambridge Univ. Press, Cambridge, 1991)

  4. 4.

    , & Systematic assessment of a maxilla of Homo from Hadar, Ethiopia. Am. J. Phys. Anthropol. 103, 235–262 (1997)

  5. 5.

    , & Paleoanthropology of the Malawi Rift: an early hominid mandible from the Chiwondo Beds, northern Malawi. J. Hum. Evol. 28, 71–108 (1995)

  6. 6.

    et al. Late Pliocene Homo and hominid land use from western Olduvai Gorge, Tanzania. Science 299, 1217–1221 (2003)

  7. 7.

    in The Cambridge History of Africa Vol. 1 From the earliest times to c. 500 BC (ed. Clark, J. D.) 70–156 (Cambridge Univ. Press, Cambridge, 1982)

  8. 8.

    in Hominidae (ed. Giacobini, G.) 141–149 (Jaca Books, Milan, 1989)

  9. 9.

    Species, species concepts and hominid evolution. J. Hum. Evol. 20, 355–371 (1991)

  10. 10.

    Paleoanthropology: the last half-century. Evol. Anthrop. 9, 2–16 (2000)

  11. 11.

    et al. A new skull of early Homo from Dmanisi, Georgia. Science 297, 85–89 (2002)

  12. 12.

    , , & Human remains from the Upper Pliocene–Early Pleistocene Dmanissi site, Georgia (1991–2000). Part I. The fossil skulls (D 2280, D 2282 and D 2700). L’Anthropol. 110, 1–110 (2006)

  13. 13.

    , , & in Handbook of Paleoanthropology Vol. 3 (eds Henke, W. & Tattersall, I.) 1655–1693 (Springer, Heidelberg, 2007)

  14. 14.

    , & Anatomical descriptions, comparative studies and evolutionary significance of the hominin skulls from Dmanisi, Republic of Georgia. J. Hum. Evol. 50, 115–141 (2006)

  15. 15.

    , , , & New fossil hominid calvaria from Indonesia—Sambungmacan 3. Anat. Rec. 262, 344–368 (2001)

  16. 16.

    , & Stratigraphic context of fossil hominids from the Omo groups deposits: northern Turkana Basin, Kenya and Ethiopia. Am. J. Phys. Anthrop. 78, 595–622 (1989)

  17. 17.

    & Energetic consequences of being a Homo erectus female. Am. J. Hum. Biol. 14, 551–565 (2002)

  18. 18.

    An alternative interpretation of the characters used to define Homo erectus. Cour. Forsch. Inst. Senckenberg 69, 167–175 (1984)

  19. 19.

    et al. Remains of Homo erectus from Bouri, Middle Awash, Ethiopia. Nature 416, 317–320 (2002)

  20. 20.

    Olduvai Gorge Vol. 3 Excavations in Beds I and II 1960–1963 (Cambridge Univ. Press, Cambridge, 1971)

  21. 21.

    Geology of Olduvai Gorge (Univ. California Press, Berkeley, 1976)

  22. 22.

    Geochronology, Geochemistry, and Isotopic Study of Plio-Pleistocene Hominid Sites and the Ngorongoro Volcanic Highlands in Northern Tanzania. PhD thesis, Univ. Colorado. (1993)

  23. 23.

    , , , & Laser-fusion 40Ar/39Ar dating of Bed I, Olduvai Gorge, Tanzania. Nature 354, 145–149 (1991)

  24. 24.

    The face of Olduvai Hominid 12. J. Hum. Evol. 46, 337–347 (2004)

  25. 25.

    , , , & Small Mid-Pleistocene hominin associated with East African Acheulean technology. Science 305, 75–78 (2004)

  26. 26.

    & Precise 40Ar/39Ar geochronology for the upper Koobi Fora Formation, Turkana Basin, northern Kenya. J. Geol. Soc. Lond. 163, 205–220 (2006)

  27. 27.

    & Stratigraphy of the Koobi Fora Formation (Pliocene and Pleistocene) in the Ileret region of northern Kenya. J. Afr. Earth Sci. 45, 369–390 (2006)

  28. 28.

    , & Sequence of tuffs between the KBS Tuff and the Chari Tuff in the Turkana Basin, Kenya and Ethiopia. J. Geol. Soc. Lond. 163, 185–204 (2006)

Download references


We thank the government of Kenya for permission to carry out this research, and the National Museums of Kenya and E. Mbua for support. The National Geographic Society funded the field work. We thank R. Blumenschine, R. Clarke, C. Dean, A. Deino, C. Feibel, Ø. Hammer, J. Harris, L. Humphrey, N. Jeffery, W. Kimbel, R. Kruszynski, K. Kupczik, D. Lieberman, C. Lockwood, D. Lordkipanidze, J. Moggi-Cecchi, S. Muteti, Ph. Rightmire, B. Sokhi, C. Swisher, A. Walker and B. Wood for their help. Caltex (Kenya) provided fuel for the field expeditions, and R. Leakey allowed us to use his aeroplane. The field expedition members included R. Bobe, G. Ekalale, C. Epaat, M. Eregei, J. Erus, J. Kaatho, S. Labun, R. Lorinyok, B. Malika, S. Muge, S. Muteti, D. Mutinda and N. Mutiwa.

Author information


  1. Department of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK

    • F. Spoor
  2. Koobi Fora Research Project, PO Box 24926, Nairobi 00502, Kenya

    • M. G. Leakey
    •  & L. N. Leakey
  3. Department of Anatomical Sciences,

    • M. G. Leakey
  4. Department of Anthropology, Stony Brook University, Stony Brook, New York 11794, USA

    • L. N. Leakey
  5. Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112, USA

    • P. N. Gathogo
    •  & F. H. Brown
  6. Department of Anthropology, New York University, New York, New York 10003, USA

    • S. C. Antón
  7. Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia

    • I. McDougall
  8. Division of Palaeontology, National Museums of Kenya, Nairobi 00100, Kenya

    • C. Kiarie
    •  & F. K. Manthi


  1. Search for F. Spoor in:

  2. Search for M. G. Leakey in:

  3. Search for P. N. Gathogo in:

  4. Search for F. H. Brown in:

  5. Search for S. C. Antón in:

  6. Search for I. McDougall in:

  7. Search for C. Kiarie in:

  8. Search for F. K. Manthi in:

  9. Search for L. N. Leakey in:

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Corresponding authors

Correspondence to F. Spoor or M. G. Leakey.

Supplementary information

PDF files

  1. 1.

    Supplementary Notes

    This file contains Supplementary Notes divided into three main sections:  1. Measurements and comparisons, including calvarial measurements of KNM-ER 42700, dental and palatal measurements of KNM-ER 42703, and a summary of morphological features used in the differential diagnoses.  2. Morphometric analyses, including principal component and bivariate analyses, and analysis of intraspecific variation of KNM-ER 42700 (four figures), and a principal component analysis of KNM-ER 42703 (one figure).   3. A brief review of the last known occurrence of H. habilis at Lower Bed II, Olduvai. Additional references are given under 4.

About this article

Publication history






Further reading


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.