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The bush of human evolution is getting bushier. New species of hominids have been discovered in Africa, Asia, and Europe in recent years that make the story of how we came to be the only species of human on earth much more complex and fascinating.

I wonder how many paleoanthropologists and neuroscientists have estimated when humans first became fully conscious. (A good working definition of consciousness, or sentience, is: Being conscious of being conscious. Although, by that definition, I’m not sure how many humans presently qualify.)

“There is nothing more seductive than having a reason to speculate about the evolution of the human brain and its intangible attributes,” says Ian Tattersall, chairman and curator of the Department of Anthropology at the American Museum of Natural History. Even so, beyond the fun (at least for some) of cogitating on the origins of cogitation, there are serious and urgent questions.

Given that the cornerstone of consciousness is self-awareness, why are so few people self-aware? Given that evolution, through its at once elegant and messy means, conferred consciousness upon us, why are modern humans at best stuck, and at worst devolving to the level of canine consciousness?

If we had a time machine that could transport us back as far as we want, we’d probably find the first emergence of people we could talk to, with translation of course, would be about 200,000 years ago. That’s when the breakthrough of ‘fully modern humans’ occurred in eastern or southern Africa, before they (we) radiated north and displaced all existing proto-human species.

These include the Neanderthals in Europe, who actually had bigger brains than we do, though not the language and technological capability; and the newly discovered Ngandong hominids in Asia. The latter, a Homo erectus lineage, evolved in isolation after an early common ancestor left Africa, and persisted for hundreds of thousands of years before being wiped out by the same species that wiped out the Neanderthals–us.

Though I studied paleoanthropology when I was a young man, I’ve forgotten much of what I learned, which is just as well, because the entire field has been turned upside down several times since. The sequences of hominid (upright walking primate) species are growing more diverse and complex, as more and more species in the human lines (there was no linear progression to modern humans) are being discovered all the time. There’s no definitive picture of which species gave rise to which, and finally to Homo sapiens.

The oldest tool use dates back a mind-boggling two and a half million years, and is called the Oldowan culture, named after Olduvai Gorge in the Great Rift Valley of eastern Africa. The basic intention of the australopiths way back then (who were not far from bipedal apes), was to obtain sharp flakes to make remarkably functional implements, capable of butchering elephants.

As Tattersall states, these primitive human ancestors “showed cognitive abilities way beyond those of apes purely through the act of making tools.” But they weren’t capable of the knowledge necessary for hunting and gathering strategies, and probably scavenged and carried off chunks of carcasses. (This was long before the discovery of fire as well.)

“To obtain a sharp flake you first have to choose a cobble of the right type, and then you have to hit this core with your hammerstone hard, and at precisely the right angle.” All this indicates a significant leap in planning and foresight. Our smartest cousins, the bonobo chimpanzees, aren’t able to get the idea, even with intensive coaching. Therefore, nearly three million years ago, scientists have the first tangible evidence of what we like to call ‘higher thought.’

About a million and a half years ago, another, more advanced type of toolmaking emerged, called Acheulean. Rather than simple flaking, it requires a ‘mental template’ to fashion an object, often a handaxe, which the proto-humans had in mind. The species of hominid that probably invented this tool-making culture, which lasted for hundreds of thousands of years, is called Homo ergaster.

All told, it’s been a long slog for the expanding hominid brain, occurring in an unknown number of lines leading to an unknown number of extinct species. Homo sapiens is but one thread through this bush, which had many divergences but ultimately led to our single, dominant species, possessing tremendous cognitive and conscious capacity.

From about 50,000 years ago in Europe and Asia, “the resident hominids lost out to the invaders”—the first fully modern humans–Homo sap. The ‘Hobbits’ (Homo floresiensis) became extinct in Indonesia 10-15 thousand years ago.

The same basic pattern was repeated within our own species right up into the 20th century, replicating the mentality of aggression and domination that our ancient ancestors displayed toward other species of humans. Indeed, the rationalization for colonization was, and still is in some quarters, that the ‘other’ isn’t human, even when they fully were, and are.

Now it’s one species of human in one messy globalized world, and there’s nowhere for our species to go, except up or down.

Evolve or perish is the law of life. The next evolutionary leap, if it occurs in more than just a few, will be the first one to be brought about consciously on this planet. And it has nothing to do with time or technology.

The human brain matters to the cosmic mind. We are the supposed winners of the hominid race. Break through.

Martin LeFevre

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