I think there is a strong argument that we have been post human since we developed writing and that a ‘person’ encompasses more than just their meat sack. I was first introduced to this idea by the book Natural Born Cyborgs. You are taking a narrower view of the word evolution, but I’m not totally sure it’s justified.

I can see the argument that it’s part of the evolutionary advantage conferred by bigger brains, vocal chords, and opposable thumbs.