The brow ridges, being a prominent part of the face in some human populations and a trait linked to sexual dimorphism, have a number of names in different disciplines.

[5] The Spatial model proposes that supraorbital torus development can be best explained in terms of the disparity between the anterior position of the orbital component relative to the neurocranium.

They proposed (as first articulated by Biegert in 1957) that during infancy the neurocranium extensively overlaps the orbit, a condition that prohibits brow ridge development.

The bio-mechanical model predicts that morphological variation in torus size is the direct product of differential tension caused by mastication, as indicated by an increase in load/lever ratio and broad craniofacial angle.

By applying pressure similar to the type associated with chewing, he carried out an analysis of the structural function of the supraorbital region on dry human and gorilla skulls.

[11][12][13] Oyen et al. conducted a cross-section study of Papio anubis in order to ascertain the relationship between palate length, incisor load and Masseter lever efficiency, relative to torus enlargement.

Employing an adult Australian sample, she tested the association between brow ridge formation and anterior dental loading, via the craniofacial angle (prosthion-nasion-metopion), maxilla breadth, and discontinuities in food preparation such as those observed between different age groups.

Finding strong support for the first two criteria, she concluded that the supraorbital complex is formed as a result of increased tension due to the widening of the maxilla, thought to be positively correlated with the size of the masseter muscle, as well as with the improper orientation of bone in the superior orbital region.

[11][15] Some researchers have suggested that brow ridges function to protect the eyes and orbital bones during hand-to-hand combat, given that they are an incredibly dimorphic trait.

The fossil record indicates that the supraorbital ridge in early hominins was reduced as the cranial vault grew; the frontal portion of the brain became positioned above rather than behind the eyes, giving a more vertical forehead.