The Neanderthal ‘‘chignon’’: Variation, integration, and homology
Philipp Gunz, Katerina Harvati*
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Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig, Germany
Received 10 May 2006; accepted 31 August 2006
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Received 10 May 2006; accepted 31 August 2006
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Abstract
The occipital bun (‘‘chignon’’) is cited widely as a Neanderthal derived trait. It encompasses the posterior projection/convexity of the
occipital squama and is associated with lambdoid flattening on the parietal. A ‘hemibun’ in some Upper Paleolithic Europeans is thought by
some authors to indicate interbreeding between Neanderthals and early modern Europeans. However, ‘bunning’ is difficult to measure, and
the term has been applied to a range of morphological patterns. Furthermore, its usefulness in phylogenetic reconstruction and its homologous
status across modern and fossil humans have been disputed. We present a geometric morphometric study that quantitatively evaluates the
chignon, assesses its usefulness in separating Neanderthals from modern humans, and its degree of similarity to Upper Paleolithic ‘hemibuns.’
We measured the three-dimensional coordinates of closely spaced points along the midsagittal plane from bregma to inion and of anatomical
landmarks in a large series of recent human crania and several Middle and Late Pleistocene European and African fossils. These coordinate data
were processed using the techniques of geometric morphometrics and analyzed with relative warps, canonical variates, and singular warps. Our
results show no separation between Neanderthals and modern humans, including early modern Europeans, when the shape of the occipital plane
midsagittal-profile is considered alone. On the other hand, Neanderthals are well separated from both recent and fossil modern humans when
information about the occipital’s relative position and relative size are also included. Furthermore, the occurrence of a highly convex and posteriorly
projecting midline occipital profile (interpreted as the occipital bun) is highly correlated (>0.8) with a flat parietal midsagittal profile and
with antero-superiorly positioned temporal bones across both our recent and our fossil human samples. We conclude that the shape of the occipital
profile alone should not be considered an independent trait, as it is very tightly integrated with braincase shape. Our analysis does not
support differences in integration of the posterior midsagittal profile and the cranial base in Pleistocene and recent humans.
The occipital bun (‘‘chignon’’) is cited widely as a Neanderthal derived trait. It encompasses the posterior projection/convexity of the
occipital squama and is associated with lambdoid flattening on the parietal. A ‘hemibun’ in some Upper Paleolithic Europeans is thought by
some authors to indicate interbreeding between Neanderthals and early modern Europeans. However, ‘bunning’ is difficult to measure, and
the term has been applied to a range of morphological patterns. Furthermore, its usefulness in phylogenetic reconstruction and its homologous
status across modern and fossil humans have been disputed. We present a geometric morphometric study that quantitatively evaluates the
chignon, assesses its usefulness in separating Neanderthals from modern humans, and its degree of similarity to Upper Paleolithic ‘hemibuns.’
We measured the three-dimensional coordinates of closely spaced points along the midsagittal plane from bregma to inion and of anatomical
landmarks in a large series of recent human crania and several Middle and Late Pleistocene European and African fossils. These coordinate data
were processed using the techniques of geometric morphometrics and analyzed with relative warps, canonical variates, and singular warps. Our
results show no separation between Neanderthals and modern humans, including early modern Europeans, when the shape of the occipital plane
midsagittal-profile is considered alone. On the other hand, Neanderthals are well separated from both recent and fossil modern humans when
information about the occipital’s relative position and relative size are also included. Furthermore, the occurrence of a highly convex and posteriorly
projecting midline occipital profile (interpreted as the occipital bun) is highly correlated (>0.8) with a flat parietal midsagittal profile and
with antero-superiorly positioned temporal bones across both our recent and our fossil human samples. We conclude that the shape of the occipital
profile alone should not be considered an independent trait, as it is very tightly integrated with braincase shape. Our analysis does not
support differences in integration of the posterior midsagittal profile and the cranial base in Pleistocene and recent humans.
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