They were the original human eyes, but they were lost as a result of the human domestication syndrome (
https://pdfs.semanticscholar.org/449...145497940e.pdf).
Modern humans have shallower orbits than pre-agricultural humans, which causes the eyeballs to be more protruding (
https://www.researchgate.net/publica..._of_the_orbits):
In China there is a reduction in facial breadth, height and prognathism, posterior tooth size, brain volume and cranial robusticity from the Neolithic to the modern period. However, the height of the orbits increases rather than decreases. Examination of the structural relationships between orbit and facial dimensions in Tohoku Japanese and Australian Aboriginal crania suggests a steady reduction in orbit volume in China. This may have resulted in a more anterior placement of the eyeball and associated structures in modern East Asians than in their Neolithic counterparts.
[...]
Where crania have a shorter cranial base, in association with a less projecting lower face and reduced upper facial breadth, orbit volumes are reduced. This would decrease the volume available for the recti muscles, and orbital nerves and blood vessels, pushing the eyeball into a more anterior or relatively protruding position. A situation analogous to this in the degree of protrusion of the eye, and extent of facial flatness, occurs in domestic breeds of dog. While there is only limited comparative evidence to support this view in humans, Adachi (1904a) suggested that this was the situation in modern Japanese when compared with other modern human populations with more projecting facial skeletons (Adachi, 1904a, b). This is in marked contrast with fossil hominids like Arago 21 (right orbit volume 44 ml, measured from a cast) and Kabwe (right orbit volume 46 ml) whose supraorbital development, facial projection and orbit volumes exceed the modern human range of variation (modern human adult orbit volume range is 18–38 ml).
Coon said that a "median eyefold" was a sign of low orbits (
https://www.theapricity.com/snpa/chapter-XII9a.htm):
In the morphology of the face, the Volhynians are for the most part typical Neo-Danubians. Median eyefolds, indicative of a low orbit and a heavy fatty deposit in the upper lid, are found among 38 per cent; the nose is concave in 25 per cent of the group, and snubbed in 20 per cent. A heavy deposit of fat on the malars is common, especially among the women; in this type it seems to assume the nature of a secondary sex character. Round faces and plump cheeks are typical.
Also here (
https://www.theapricity.com/snpa/chapter-IX9.htm):
However, there seems to be a moderately high incidence of concavity of the nasal profile, 18 per cent among Mordvins and 39 per cent among Cheremisses; of a median eyefold, which is a sign, as a rule, of a low bony orbit - 34 per cent among Mordvins and 46 per cent among Cheremisses; and 64 per cent of weak beard growth among Mordvins, and 77 per cent among Cheremisses.
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