The Moral Animal by Robert Wright.
EDIT: The comment above made a good point. Do you mean "conscience" or "consciousness"? Moral Animal is good for conscience, not so good for consciousness.
Seconded. Anyone that interacts with humans on a regular basis should read that book, especially those who have trouble doing it "naturally."
I've heard The Origin of Consciousness in the Breakdown of the Bicameral Mind spoken of quite highly, but don't know much about it.
Two key words on the evolution of the moral conscience are:
Joyce, The Evolution of Morality
de Waal et. al., Primates and Philosophers: How Morality Evolved
I am looking for books on evolution of conscience. Please suggest. I searched but nothing good came out.
I don't know if this is the right place for such requests.
If this is not the right place, pls tell me, i will delete this post.
Thanks.