Pre-Bed Thought

I read something today that raised the question, "Why did we evolve consciousness?" It is, of course, a fun question: Couldn't we do exactly the same stuff if we weren't there witnessing it? I haven't given the question appropriate consideration, but here are my first thoughts:

We could have evolved consciousness because it's the most efficient way to make us unpredictable. Unpredictability has clear benefits for survival...it's harder for animals to hunt you or for other people to trick you if they don't know you'll react the same way to nearly identical stimuli. And although I'm more or less a determinist, certainly the factors that sway decisions can be extremely subtle and nigh impossible to control for. It's really hard to create a random number generator, so perhaps consciousness is the closest we can get with reasonable efficiency. Also (and similarly), consciousness may us to adapt to new situations. We can extrapolate not only rules but probabilities from our past experiences and apply them to the present. Maybe consciousness is a good tool in extrapolation and probability gaging.

Then again, maybe not. I'm just throwing the possibility out there...