I wouldn’t know about the hence part, but I always read it as “years from now”. A bit like the opposite from “years since”.
As for the other thing, it started out with deliberately engineered beings for specific tasks like the vacuumorph.
About a hundred years later the remaining people would create new humans with the specific goal of being able to survive the harsher environment of a ravaged earth. It was these that evolved further into different creatures.
It’s a pretty far fetched story either way, I just like it for the weird pictures :)
I posted a link in one of the other replies. You can read the whole thing there if you’re interested, there’s a timeline on page 20 if you just want a quick overview.