No one is drawing any conclusions between how atmospheric ether may have had an influence on what the sundered humanity eventually became? It seems very possible to me. We know Ether has alteration properties on individuals when an overwhelming amount suffuses into a being. These Lesser humans (the sundered humanity), don't have as much either as their original bodies and thus would likely be vulnerable to etheric alteration by their dense ether-infused environments. We don't know where each race originally lived and its ether levels but it very much may have altered their physiology over time. Sun Tribe Miq'ote for example likely came from a hot sunny place, hence their constricted pupils though since they have duller teeth than the Moon Tribe perhaps they didn't hunt with their natural weapons as often and ate mostly grown foods, whereas the Moon Tribe lived in darker, colder environments and thus kept or developed fangs and wider pupils for better hunting at night. We also know people from the past had the ability to transform, perhaps some bastardized version of this trait is what caused all post sundering people to mutate into their current racial equivalents?