I've been listening to Annaka Harris on Sam Harris's podcast. One interesting takeaway:

• If consciousness evolved, it must have had an evolutionary value or be co-occurring with another trait that does.
• In case none of the above are true, it would follow that consciousness just is -- evolution would have been a force in play to make it appear at some stage in our development, but if evolution wasn't involved, it seems likely that consciousness would be just a side-effect of matter existing. Or of matter doing computation, if you follow the "information integration" theory.

My hypothesis, no particularly insightful: consciousness and the self is a requisite for complex communication, and thus has actual evolutionary value in social animals.