From what I have read of the populations of Australia, and to a lesser extent, the Americas, such group onsciousness may have dominated until contact. But it also appears that such mimetic systems, once they have evolved, spread by contagion, transforming even populations that are not yet otherwise cuulturally, or possibly even psychologically adapted to it.
The phenomenae Jayne observed in his work on the bicameral mind was the emergence of the concept embodied in the pronoun "I", which he saw indicative of the emergence of individual consciousness, yet does not appear in the earlist books of Genesis or the entire Illiad. I suspect by this time the change was linguistic, and represented a focusing of individual consciousness so exstreme it made the memes of an individual more important than the group meme. Before this, in the Illiad and Odyssey, they speak of shame, which is something one feels in relation to others. After that, they speak of guilt, which follows one to the wastelands. The actual transition to verbal consciousness, much less its first emergence in some twinspeak, were, I suspect, much earlier.
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