Also, we have seen 0 evidence that there has been any significant brain development, none. Not a shred. So that argument doesn't even hold water with the evidence that we do have. For as far back as we have been able to study homo sapiens and our ancestors, all we have to go on is some rather speculative concepts based on skull formation. Nothing more.-We know the brain size from the skulls. we have no idea how much development within the brain occurred and when it occurred.