Consciousness: Half an oaf is better than none?

My chief difficulty with materialist theories of consciousness is the apparent fact that human consciousness got started rather suddenly, and was not really the result of a long slow series of primate steps.

We do not go from the fruit-throwing ape to the cave paintings in a long, slow series of steps.

Therefore, this is NOT the sequence:

ape
brute
oaf
not just an oaf
not quite an oaf
somewhat less oafish

[ ... ]

a bit less oafish than when last noticed
many oafish characteristics have been lost
not nearly the oaf he used to be

[ ... ... ... ] (and finally!)

if we have him over for dinner, we can seat him at the table instead of tying him in the yard with a bowl of water and a biscuit

The quest: Given that this story never happened, what did?

Other Mindful Hack stories on consciousness:

The difference between thinking and consciousness

Consciousness: So familiar and yet so puzzling?

The Spiritual Brain: Vindicating Alfred Russel Wallace?

Belated sublimely ridiculous award for 2006

Materialists start to come to grips with global failure but materialism dies hard

Mind vs. meat vs. computers: The differences

Consciousness: Recent public squabble between philosophers of mind rates better than most sitcoms

Interview with Spiritual Brain authors Mario and Denyse at campus Web site

Books: New physics takes on the human mind

Is consciousness a trick to ensure survival?

The Spiritual Brain reviewed in Jesuit thinkmag America