Last week was a big one for the human family tree -- it grew by a million years. With considerable splash the media announced that our oldest ancestor was Ardi, short for Ardipithecus ramidus, an upright walking hominid who lived 4.4 million years ago. A female skeleton was put on display that demotes Lucy, another female skeleton that became famous as the oldest hominid, dating from only 3.2 million years.
As usual when such stories about evolution reach the front page, religious believers are quieted. Unless you have absolute faith in Genesis, there is irrefutable evidence that physical life developed by stages. Ardi wasn't exactly a newcomer. The first remains, in the form of a single molar, had been found in Ethiopia in 1992, and for seventeen years teams of specialists determined a host of facts about this new species. For example, walking upright had already been developed four million years ago, along with tree-climbing, and an omnivorous appetite for almost any kind of food, plant or animal.
Indirectly creationists were handed a sliver of a concession. Ardi isn't apelike. We aren't descended from monkeys, once again laying to rest the most shocking theory that used to circulate in common parlance. By walking upright over four million years ago, the earliest hominids were already on an evolutionary track separate from even chimps and gorillas, our nearest genetic cousins, who locomote with a different kind of gait known as knuckle-walking.
Yet it's what we don't know about our ancestors that's the most thrilling. Nothing in the fossil record, no matter how many dozen specialists study it, explains the trait that makes us human. It's not walking upright or learning to mate for life (some anthropologists speculate that this was already developing with Ardi and Lucy). It's not the opposable thumb and forefinger, which have long been touted as the one great advantage we have over all other primates.
The dominant trait that makes us human is our self-consciousness, which will never be viewed in the fossil record, because it's invisible. Being self-conscious, human beings became curious about ourselves and where we came from. That's why we study chimps but they don't study us. Other primates have had the same millions of years to become self-conscious. Somehow it never caught on beyond a certain basic level, while we on the other hand grew more self-conscious over time. When the Buddha looked inward and Christ preached a gospel of love, those were evolutionary steps in human awareness.
Evolution has reached the point where there's no more physical development left for us. Escaping the rule of survival of the fittest -- that no longer applies to a species that takes care of its weak and sick -- human beings entered the era of survival of the wisest. Survival of the wisest means using our consciousness in the highest way possible, for peace, shared resources, the eradication of disease, and increased happiness.
In terms of self-consciousness, the next great leap won't be in any of these areas, however. It will come when we figure out how brain cells work. Neuroscientists, like their colleagues in anthropology, keep staring at what's visible when the secrets of the brain are clearly invisible. Where is memory imprinted in a neuron? What is the self, which appears to have no identifiable location in the brain? How do vibrating molecules striking the eardrum turn into words that convey meaning? When photons stimulate cells on the surface of the retina, how do mere electrical impulses in the visual cortex create the world we see?
Inside the brain there are no sounds or sights. When you hear music, your brain remains completely silent. When you gaze at a sunset, your brain remains totally dark. The study of cells and tissues, like the study of fossils, offers clues about the mystery of consciousness, yet a great divide has yet to be crossed. We need a Darwin of consciousness, a seminal mind who grasps the mind itself. Only then will Ardi and Lucy make sense. Because right now they don't. The creationists are defending a rear-guard position that will never be true. At the same time, so are the materialists they oppose. Consciousness is the creative force we have yet to unravel. It creates sight, sound, touch, taste, and smell. Which means that the real thrills are yet to come, when we look inward to discover the most mind-bending thing of all: Consciousness is the basic building block of life and the prime mover of the universe.