A geometric morphometric approach to the study of sexual dimorphism in the modern human frontal bone

Abstract

Objectives: We analyzed the main anatomical traits found in the human frontal bone by using a geometric morphometric approach. The objectives of this study are to explore how the frontal bone morphology varies between the sexes and to detect which part of the frontal bone are sexually dimorphic. Materials and methods: The sample is composed of 161 skulls of European and North American individuals of known sex. For each cranium, we collected 3D landmarks and semilandmarks on the frontal bone, to examine the entire morphology and separate modules (frontal squama, supraorbital ridges, glabellar region, temporal lines, and mid-sagittal profile). We used Procrustes ANOVAs and LDAs (linear discriminant analyses) to evaluate the relation between frontal bone morphology and sexual dimorphism and to calculate precision and accuracy in the classification of sex. Results: All the frontal bone traits are influenced by sexual dimorphism, though each in a different manner. Variation in shape and size differs between the sexes, and this study confirmed that the supraorbital ridges and glabella are the most important regions for sex determination, although there is no covariation between them. The variable size does not contribute significantly to the discrimination between sexes. Thanks to a geometric morphometric analysis, it was found that the size variable is not an important element for the determination of sex in the frontal bone. Conclusion: The usage of geometric morphometrics in analyzing the frontal bone has led to new knowledge on the morphological variations due to sexual dimorphism. The proposed protocol permits to quantify morphological covariation between modules, to calculate the shape variations related to sexual dimorphism including or omitting the variable size.

The Scientific Profiles of Documented Collections via Publication Data: Past, Present, and Future Directions in Forensic Anthropology

“…The altmetric scores illustrate the relevance of social media and secondary sources or research to a given paper's visibility, and the importance of the social and cultural contexts when promoting research. Of the TOP5 papers, one introduces a new DC [35], and three papers address sex and age assessment estimations [36][37][38]. The paper with the highest score is mentioned in nine news stories and was tweeted 24 times.…”

“…When compared to the overall sample assessment of the TOP5 articles (Table 1), the overall profile is similar: the emphasis is placed on researchbased papers on biological profiling that are based on sex, age at death, activity, and stature, with one paper introducing a new documented collection, The 21st Century Identified Skeletal Collection [42]. These are all papers relevant to forensic research, except A geometric morphometric approach to the study of sexual dimorphism in the modern human frontal bone Del Bove et al [38] American Journal of Physical Anthropology 2020 1 17…”

Sex estimation through geometric morphometric analysis of the frontal bone: an assessment in pre-pubertal and post-pubertal modern Spanish population

“…Del Bove et al (2019) using a morphometric approach on the outer surface of the frontal bone established a hierarchy of importance of sexually dimorphic areas of the frontal bone. Their study highlighted how the supraorbital ridges and the glabellar region were the most valuable areas for sex estimation, while the variable size, of frontal bone measurements, was not strongly related to sex [ 19 ].…”

Exploring sexual dimorphism of human occipital and temporal bones through geometric morphometrics in an identified Western‐European sample

“…In the last decade, GM has been used to explore cranial sexual dimorphism in distinct populations all over the world demonstrating its population‐based expression. Studies have been undertaken in countries such as south‐east Asia (Green & Curvoe, 2009), America (Garvin & Ruff, 2012; Kimmerle et al, 2008), Europe (Bigoni et al, 2010; Chovalopoulou et al, 2013; Del Bove et al, 2020; Gonzalez et al, 2011; Guyomarc'h & Bruzek, 2010; Milella et al, 2021; Rosas & Bastir, 2002), and South‐Africa (Franklin et al, 2006; Pretorius et al, 2006). Most of these studies have focused their analysis on particular facial features (e.g., such as the orbital shape, browridges, glabellar region, and chin) (Del Bove et al, 2020; Garvin & Ruff, 2012; Pretorius et al, 2006) or on the whole cranial configuration (Gonzalez et al, 2011; Guyomarc'h & Bruzek, 2010; Kimmerle et al, 2008; Rosas & Bastir, 2002).…”