Chipping in to mention that almost all the races are, indeed, descended from one ephemeral race which split into two which then developed into all the various species of men and elves. The notable exception being the lizard folk. They are actually a leftover remnant from before current creation, the only one of the 12 worlds smashed together that remained in-tact. The Hist are literally alien tree-gods more ancient than creation, and the Argonians are their personal slave-race, so they could have just one day decided their lizard women would have boobs for whatever reason and made it happen.They're reptiles so I'd assume it's just fat. As other races interacted with Argonian society, it's possible that male Argonains began to appreciate the booba which through years of selective breeding led to the development of Argonian tiddies. That or every race in skyrim is just a heavily mutated version of ancient human which was wiped out by a catastrophic world event. idk
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