The relative role of drift and selection in shaping the human skull
Article first published online: 6 JUL 2009
Copyright © 2009 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 141, Issue 1, pages 76–82, January 2010
How to Cite
Betti, L., Balloux, F., Hanihara, T. and Manica, A. (2010), The relative role of drift and selection in shaping the human skull. Am. J. Phys. Anthropol., 141: 76–82. doi: 10.1002/ajpa.21115
- Issue published online: 9 DEC 2009
- Article first published online: 6 JUL 2009
- Manuscript Accepted: 8 MAY 2009
- Manuscript Received: 11 MAR 2009
- Leverhulme Trust
- neutral processes;
- geographic patterns;
- skull traits
Human populations across the world vary greatly in cranial morphology. It is highly debated to what extent this variability has accumulated through neutral processes (genetic drift) or through natural selection driven by climate. By taking advantage of recent work showing that geographic distance along landmasses is an excellent proxy for neutral genetic differentiation, we quantify the relative role of drift versus selection in an exceptionally large dataset of human skulls. We show that neutral processes have been much more important than climate in shaping the human cranium. We further demonstrate that a large proportion of the signal for natural selection comes from populations from extremely cold regions. More generally, we show that, if drift is not explicitly accounted for, the effect of natural selection can be greatly overestimated. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc.