Three‐dimensional analysis of sexual dimorphism in the soft tissue morphology of the upper airways in a human population

• Published in: American journal of physical anthropology 2020-01, Vol.171 (1), p.65-75
• Main Authors: Bastir, Markus, Megía, Irene, Torres‐Tamayo, Nicole, García‐Martínez, Daniel, Piqueras, Francisco M., Burgos, Manuel
• Format: Article
• Language: English
• Subjects: Air flow; Computed tomography; Dimensional analysis; geometric morphometrics; Homo sapiens; Human populations; Humans; Landmarks; Males; Morphology; nasal fossae; sexual differences; Tomography; upper airways
• ISSN: 0002-9483; 1096-8644; 2692-7691
• DOI: 10.1002/ajpa.23944

Objectives Several studies have analyzed the sexual dimorphism of the skeletal cranial airways. This study aimed to quantify the three‐dimensional (3D) morphology of the soft tissues of the upper airways in a human population. We addressed hypotheses about morphological features related to respiratory and energetic aspects of nasal sexual dimorphism. Methods We reconstructed 3D models of 41 male and female soft tissue nasal airways from computed tomography data. We measured 280 landmarks and semilandmarks for 3D‐geometric morphometric analyses to test for differences in size and 3D morphology of different functional compartments of the soft tissue airways. Results We found statistical evidence for sexual dimorphism: Males were larger than females. 3D features indicated taller and wider inflow tracts, taller outflow tracts and slightly taller internal airways in males. These characteristics are compatible with greater airflow in males. Discussion The differences in 3D nasal airway morphology are compatible with the respiratory‐energetics hypothesis according to which males differ from females because of greater energetic demands. Accordingly, structures related to inflow and outflow of air show stronger signals than structures relevant for air‐conditioning.