A lack of sexual dimorphism in width-to-height ratio in White European faces using 2D photographs, 3D scans, and anthropometry

Facial width-to-height ratio has received a great deal of attention in recent research. Evidence from human skulls suggests

that males have a larger relative facial width than females, and that this sexual dimorphism is an honest signal of

masculinity, aggression, and related traits. However, evidence that this measure is sexually dimorphic in faces, rather than

skulls, is surprisingly weak. We therefore investigated facial width-to-height ratio in three White European samples using

three different methods of measurement: 2D photographs, 3D scans, and anthropometry. By measuring the same

individuals with multiple methods, we demonstrated high agreement across all measures. However, we found no evidence

of sexual dimorphism in the face. In our third study, we also found a link between facial width-to-height ratio and body

mass index for both males and females, although this relationship did not account for the lack of dimorphism in our sample.

While we showed sufficient power to detect differences between male and female width-to-height ratio, our results failed to

support the general hypothesis of sexual dimorphism in the face.