Early modern human diversity suggests subdivided population structure and a complex out-of-Africa scenario

Edited by Erik Trinkaus, Washington University, St. Louis, MO, and approved January 15, 2009
April 14, 2009
106 (15) 6094-6098

Abstract

The interpretation of genetic evidence regarding modern human origins depends, among other things, on assessments of the structure and the variation of ancient populations. Because we lack genetic data from the time when the first anatomically modern humans appeared, between 200,000 and 60,000 years ago, instead we exploit the phenotype of neurocranial geometry to compare the variation in early modern human fossils with that in other groups of fossil Homo and recent modern humans. Variation is assessed as the mean-squared Procrustes distance from the group average shape in a representation based on several hundred neurocranial landmarks and semilandmarks. We find that the early modern group has more shape variation than any other group in our sample, which covers 1.8 million years, and that they are morphologically similar to recent modern humans of diverse geographically dispersed populations but not to archaic groups. Of the currently competing models of modern human origins, some are inconsistent with these findings. Rather than a single out-of-Africa dispersal scenario, we suggest that early modern humans were already divided into different populations in Pleistocene Africa, after which there followed a complex migration pattern. Our conclusions bear implications for the inference of ancient human demography from genetic models and emphasize the importance of focusing research on those early modern humans, in particular, in Africa.

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Acknowledgments.

We thank M. Teschler-Nicola and M. Berner at the Naturhistorisches Museum Wien; C. Stringer and R. Kruszynski at the Natural History Museum London; the Johann Wolfgang Goethe-University in Frankfurt am Main; C. Magori, C. Saanane, and D. Kamamba from Antiquities Tanzania; J. H. Mariam from ARCCH Ethiopia; and M. Yilma from the National Museum Addis Ababa for access to their collection of fossils and casts; and M. Bernhard and C. Fenes for sharing data from modern humans. We thank D. Lieberman from Harvard University for access to Skhūl 5 CT data; J.L. Arsuaga, G. Koufos, L. Bondioli, and R. Macchiarelli for permission to scan fossil specimens; W. Recheis and D. zur Nedden at the University Hospital Innsbruck and H. Imhof and F. Kainberger at the General Hospital Vienna for technical support; and J. J. Hublin, K. Harvati, J. Schwartz, T. B. Viola, and S. Neubauer for discussion and support. This work was supported by EU FP6 Marie Curie Actions “EVAN,” the Austrian Science Foundation, the Austrian Council for Science and Technology, and the Austrian Federal Ministry for Education, Science and Culture.

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Information & Authors

Information

Published in

Go to Proceedings of the National Academy of Sciences
Proceedings of the National Academy of Sciences
Vol. 106 | No. 15
April 14, 2009
PubMed: 19307568

Classifications

Submission history

Received: September 1, 2008
Published online: April 14, 2009
Published in issue: April 14, 2009

Keywords

  1. early anatomically modern humans
  2. evolution
  3. migration
  4. morphological
  5. morphometrics

Acknowledgments

We thank M. Teschler-Nicola and M. Berner at the Naturhistorisches Museum Wien; C. Stringer and R. Kruszynski at the Natural History Museum London; the Johann Wolfgang Goethe-University in Frankfurt am Main; C. Magori, C. Saanane, and D. Kamamba from Antiquities Tanzania; J. H. Mariam from ARCCH Ethiopia; and M. Yilma from the National Museum Addis Ababa for access to their collection of fossils and casts; and M. Bernhard and C. Fenes for sharing data from modern humans. We thank D. Lieberman from Harvard University for access to Skhūl 5 CT data; J.L. Arsuaga, G. Koufos, L. Bondioli, and R. Macchiarelli for permission to scan fossil specimens; W. Recheis and D. zur Nedden at the University Hospital Innsbruck and H. Imhof and F. Kainberger at the General Hospital Vienna for technical support; and J. J. Hublin, K. Harvati, J. Schwartz, T. B. Viola, and S. Neubauer for discussion and support. This work was supported by EU FP6 Marie Curie Actions “EVAN,” the Austrian Science Foundation, the Austrian Council for Science and Technology, and the Austrian Federal Ministry for Education, Science and Culture.

Notes

This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0808160106/DCSupplemental.

Authors

Affiliations

Philipp Gunz
Departments of aAnthropology and
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig, Germany;
Fred L. Bookstein
Departments of aAnthropology and
Department of Statistics, University of Washington, Seattle, WA 98195; and
Philipp Mitteroecker
Departments of aAnthropology and
Theoretical Biology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria;
Andrea Stadlmayr
Departments of aAnthropology and
Horst Seidler
Departments of aAnthropology and
Gerhard W. Weber1 [email protected]
Departments of aAnthropology and
dKonrad Lorenz Institute for Evolution and Cognition Research, Adolf Lorenz Gasse 2, A-3422 Altenberg, Austria

Notes

1
To whom correspondence should be addressed. E-mail: [email protected]
Author contributions: G.W.W. designed research; P.G., F.L.B., P.M., A.S., H.S., and G.W.W. performed research; P.G., F.L.B., P.M., and A.S. analyzed data; and P.G., F.L.B., and G.W.W. wrote the paper.

Competing Interests

The authors declare no conflict of interest.

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    Early modern human diversity suggests subdivided population structure and a complex out-of-Africa scenario
    Proceedings of the National Academy of Sciences
    • Vol. 106
    • No. 15
    • pp. 6025-6423

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