Associations of Facial Shape With Physical Strength and 2D:4D in a Turkish Male and Female Sample

IF 1.6 4区医学 Q1 ANTHROPOLOGY

American Journal of Human Biology Pub Date : 2024-09-12 DOI:10.1002/ajhb.24155

Fatih Aydık, Berna Ertuğrul, Sonja Windhager, Barış Özener

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引用次数: 0

Abstract

Objective

Human sexual dimorphism in physical strength manifests itself in men having a greater muscle mass than women, reflecting ancestral roles in competition, protection, and provisioning. Prenatal testosterone exposure, approximated via the second-to-fourth digit ratio (2D:4D), is linked to increased muscular strength in both sexes, indicating a developmental influence. Previous research has shown that both physical strength and 2D:4D have facial shape correlates, especially in men, but most studies have focused on Western populations and one trait. We therefore hypothesized a broader relationship between facial shape and both physical strength and 2D:4D.

Materials and Methods

In this study, we quantified the association between facial shape, handgrip strength (HGS), and 2D:4D in a non-Western Turkish sample (72 men, 55 women; Md = 22 y, SIR = 1.8 y) using two dimensional geometric morphometrics. Thirty-eight somatometric and 32 semi-landmarks were digitized on facial photographs taken in frontal view. Physical strength was assessed via handgrip strength (HGS), and the second digit length was divided by the fourth digit length to calculate 2D:4D.

Results

Both HGS and 2D:4D were significantly associated with shape in both sexes, but only in men did they explain a significant amount of facial variation. Thin-plates spline deformation grids and geometric morphometric morphs visualized the facial shape changes related to variations in handgrip strength, 2D:4D, and sexual dimorphism, enabling trait comparisons.

Conclusion

This study contributes a comparative sample from the Middle East, which is indispensable to discern universalities from Western peculiarities. It provides evidence to better understand the biological basis of facial traits, which can potentially serve as increasingly relevant social cues in today's online and digital environments.

Abstract Image

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土耳其男女样本中脸型与体力和 2D:4D 的关系

目的人类在体力方面的性别二形性表现为男性的肌肉质量大于女性，这反映了男性在竞争、保护和供给方面的祖先角色。产前睾酮暴露（通过第二位数字与第四位数字之比（2D:4D）估算）与两性肌肉力量的增加有关，这表明存在发育影响。以往的研究表明，体力和 2D:4D 都与脸型有关，尤其是在男性中，但大多数研究都集中在西方人群和一种特征上。因此，我们假设面部形状与体力和 2D:4D 之间存在更广泛的关系。材料与方法在这项研究中，我们使用二维几何形态计量学量化了非西方土耳其样本（72 名男性，55 名女性；Md = 22 y，SIR = 1.8 y）中面部形状、手握强度（HGS）和 2D:4D 之间的关联。在正面拍摄的面部照片上数字化了 38 个体征和 32 个半体征。结果HGS和2D:4D与男性和女性的脸型都有显著的相关性，但只有男性的脸型变化与HGS和2D:4D有显著的相关性。薄板样条变形网格和几何形态计量学形态将与手握强度、2D:4D 和性二态变化相关的面部形状变化可视化，从而实现了性状比较。它为更好地理解面部特征的生物学基础提供了证据，在当今的网络和数字环境中，面部特征有可能成为越来越重要的社交线索。

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来源期刊

American Journal of Human Biology 生物-生物学

CiteScore

4.80

自引率

13.80%

发文量

124

审稿时长

4-8 weeks

期刊介绍： The American Journal of Human Biology is the Official Journal of the Human Biology Association. The American Journal of Human Biology is a bimonthly, peer-reviewed, internationally circulated journal that publishes reports of original research, theoretical articles and timely reviews, and brief communications in the interdisciplinary field of human biology. As the official journal of the Human Biology Association, the Journal also publishes abstracts of research presented at its annual scientific meeting and book reviews relevant to the field. The Journal seeks scholarly manuscripts that address all aspects of human biology, health, and disease, particularly those that stress comparative, developmental, ecological, or evolutionary perspectives. The transdisciplinary areas covered in the Journal include, but are not limited to, epidemiology, genetic variation, population biology and demography, physiology, anatomy, nutrition, growth and aging, physical performance, physical activity and fitness, ecology, and evolution, along with their interactions. The Journal publishes basic, applied, and methodologically oriented research from all areas, including measurement, analytical techniques and strategies, and computer applications in human biology. Like many other biologically oriented disciplines, the field of human biology has undergone considerable growth and diversification in recent years, and the expansion of the aims and scope of the Journal is a reflection of this growth and membership diversification. The Journal is committed to prompt review, and priority publication is given to manuscripts with novel or timely findings, and to manuscripts of unusual interest.