Secular trends in cranial morphological traits: a socioeconomic perspective of change and sexual dimorphism in North Americans 1849–1960

Abstract

Background: The human body has undergone significant changes in stature and other areas, which reflect secular trends associated with socioeconomics.

Aim: To analyse cranial morphological traits for deciphering if they are subject to secular trends.

Subjects and methods: Two documented skeletal collections were sampled for a total of 525 individuals from 1849–1960. Cranial morphological traits were scored and input into time series statistics (logistic regression).

Results: In females, nuchal crests have enlarged, while glabella has decreased. In males, supraorbital margins have dulled, while glabella decreased. Sexual dimorphism increased in supraorbital margins.

Conclusion: The patterns in the data here reflect those found in other areas of the skeleton, namely height, as regards to secular trends. These findings can be extended to stature and cranial changes that parallel socioeconomic trends during the Industrial Revolution, antebellum period and after.

• Health status
• nutritional stress
• secular change
• sex characteristics
• sex estimation
• sexual dimorphism

Acknowledgements

First, Angela Dautartas’ contribution to the poster presentation that was eventually revised, re-analysed and turned into this paper is much appreciated. A special thank you goes to both Dr Richard Jantz and Dr Lee Meadows Jantz, who provided valuable feedback on the project proposal and permission to use the Donated Collection. I would also like to thank Dr Yohannes Haile-Selassie and Lyman Jellema for allowing me access to the Hamann-Todd Collection. Lastly, thank you to the anonymous reviewers whose feedback greatly improved this manuscript. This work was funded by a William M. Bass Endowment.

Declaration of interest

The author reports no conflicts of interest. The author alone is responsible for the content and writing of the paper.