Dataset Information

Three-dimensional geometric morphometric studies of modern human occipital variation.

ABSTRACT:

Objectives

To investigate three-dimensional morphological variation of the occipital bone between sexes and among populations, to determine how ancestry, sex and size account for occipital shape variation and to describe the exact forms by which the differences are expressed.

Methods

CT data for 214 modern crania of Asian, African and European ancestry were compared using 3D geometric morphometrics and multivariate statistics, including principal component analysis, Hotelling's T2 test, multivariate regression, ANOVA, and MANCOVA.

Results

Sex differences in average occipital morphology are only observed in Europeans, with males exhibiting a pronounced inion. Significant ancestral differences are observed among all samples and are shared by males and females. Asian and African crania have smaller biasterionic breadths and flatter clivus angles compared to Europeans. Asian and European crania are similar in their nuchal and occipital plane proportions, nuchal and occipital angles, and lower inion positions compared to Africans. Centroid size significantly differs between sexes and among populations. The overall allometry, while significant, explains little of the shape variation. Larger occipital bones were associated with a more curved occipital plane, a pronounced inion, a narrower biasterionic breadth, a more flexed clivus, and a lower and relatively smaller foramen magnum.

Conclusions

Although significant shape differences were observed among populations, it is not recommended to use occipital morphology in sex or population estimation as both factors explained little of the observed variance. Other factors, relating to function and the environment, are suggested to be greater contributors to occipital variation. For the same reason, it is also not recommended to use the occiput in phylogenetic studies.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC7808672 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Publications

Three-dimensional geometric morphometric studies of modern human occipital variation.

Zhang Yameng Y Schepartz Lynne A LA

PloS one 20210114 1

<h4>Objectives</h4>To investigate three-dimensional morphological variation of the occipital bone between sexes and among populations, to determine how ancestry, sex and size account for occipital shape variation and to describe the exact forms by which the differences are expressed.<h4>Methods</h4>CT data for 214 modern crania of Asian, African and European ancestry were compared using 3D geometric morphometrics and multivariate statistics, including principal component analysis, Hotelling's T2 ...[more]

PMID: 33444349

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Dataset Information

Three-dimensional geometric morphometric studies of modern human occipital variation.

Objectives

Methods

Results

Conclusions

Publications

Three-dimensional geometric morphometric studies of modern human occipital variation.

Similar Datasets

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