Evolutionary Theories of Religion

[Clueless Morgan]

I'm surprised that a #3 isn't included that mentions phenomena like pareidolia, apophenia and agency-detection coupled with the human capacity for abstract thinking.  To me, that seems the most convincing reasons humans might have evolved a tendency for superstitious/religious thought.  From this fairly reasonable starting point (to me at least), you can get to #2, and then to #1.

I don't see #1 being a stand-alone explanation for why humans evolved religiosity without some kind of agency-detection system already being in place, and an agency-detection system would be the thing that builds the religious framework that is then used to explain the existential questions being asked, and, as the OP states, #2 can be achieved by so many other successful methods that religiosity doesn't seem wholly sufficient as an explanation.

Is human agency detection different from other mammals' agency detection? Why is it that humans' agency detection builds the religious framework?

It doesn't appear to be the case that agency detection is significantly different in humans than other animals.  The difference between agency-detection leading to religiosity versus agency-detection that doesn't seems to lay, therefore, in the human capacity for abstract thinking which does seem to be unique to us and no other animal (yet discovered).  Hence why, in the quote above, I said:

I'm surprised that a #3 isn't included that mentions phenomena like pareidolia, apophenia and agency-detection coupled with the human capacity for abstract thinking.