I found a very interesting article. It is about some primates in South America which began evolving larger brains. It made me think of the late Stephen Jay Gould's view that evolution is radically contingent. Perhaps its not so after all. I mean, if Homo Erectus had gone extinct before our lineage evolved from it, perhaps 10 million years later another group of apes (or any other creature, for all we know) may have evolved our level of consciousness.