Everyone agrees that humans have many characteristics that have never been described in any other primate. Where, when, and why did the human lineage evolve each of those unique characteristics? 
It seems that scientists are thinking there was a unique selection pressure or mutation for each human characteristic. Most paleoanthropologists have given up ever knowing the where-when-why's. Isn't it scientifically logical (parsimonious) that there was a single cause for most of them? (as I was trying to explain here).
Elaine Morgan could relate many physical characteristics to the aquatic ape theory, and Craig Hagstrom could relate many emotional and behavioral characteristics to that same theory. I think I found the place where it happened. There was one ring that ruled them all: the coastline of Bioko island. 

One ring ruled them all,
One ring confined them.
One ring made them tame,
And thoroughly mankind them.