Final answer:
The shape of eye orbits among different human racial categories is not a valid concept, as modern science understands that such physical traits do not accurately reflect genetic differences among individuals. Differences in orbit shape are minimal, and all human orbits essentially perform the same functions.
Step-by-step explanation:
The question pertains to the shape of eye orbits among different historical classifications of human skulls, namely Caucasoid, Negroid, and Mongoloid. These terms, while outdated and rooted in the pseudoscientific field of craniometry, referred to generalized skull shapes believed to correspond with certain racial groups. The orbit is the bony structure around the eye. It is cone-shaped with a narrower posterior region that becomes wider at the large anterior opening. As modern science has made clear, the concept of race based on physical attributes such as skull and orbit shape is not supported by genetic evidence. Moreover human skulls do not conform to a consistent set pattern based on such categories, and any observed differences are mostly statistical and represent a wide range of variation within all human populations.
In fact the content loaded notions of racial differences in orbit shape have been thoroughly debunked. All human beings have orbits that serve the purpose of housing the eyeball and muscles necessary for eye movement and upper eyelid opening. Despite differences that may appear in the various now-deprecated racial categories there is far greater similarity among human orbits than difference, and they all provide the needed protection and function for the eye.