Would still like to know how mankind deviated into so many different variants

[Naria]

Well, it's not an actual confirmation, but a sidequest in Elpis hints strongly that at least one modern-day race was a pre-Sundering creation by the Ancients suprisingly (or not), the matanga/arkasodara (the quest is 'Terror on Two Legs', where you have to track down a creation that has gone berserk, and it turns out it's a small matanga. The end of the quest states that it seemed to be highly intelligent and that the researchers were considering giving it the power of speech accordingly).

So, assuming that creation was the origin of the matanga/arkasodara, then, potentially, all sentient races could potentially be. But again that's just assumptions on my part.

There is also this in Ktisis Hyperboreia:





I think it is a probable origin for the Lupin. Which might have interesting implications for the 1st boss of Ktisis assuming that boss is the prototype. Although I do think the 1st boss looks more like a cat (or even a Hrothgar) than a wolf, so I am assuming these are two different concepts.