Monday, May 28, 2018

Cavemen Rule, Part VI: Homo Erectus (huh huh huh)


Dating

Ergaster/Erectus was the most successful Homo species, attested from almost two million years ago to as recently as 150 thousand years ago.  Sometimes you’ll see weird dates like fifty thousand years ago, or even ten thousand years ago, but the former was re-dated in 2011(1), while the latter is more likely the result of artificial cranial deformation among modern    humans(2).  Personally, in the latter case, I think it would be cool to sample the DNA, just to be   sure—but the remains in question were repatriated to the indigenous people on whose land they were found .

At any rate, the most recent undisputed Erectus remains were found near the Solo River in Indonesia; they were dated to between 140 KYA and 550 KYA.  This seems like a big gap, but even at the most conservative estimate, that would mean these guys were around for a million and a half years.  

Compare that with our species, Homo sapiens, which has only been around for 200 KYA—an eighth of that time!  By timespan alone, that makes them much more successful than us, especially if things keep going they way they are with North Korea!

I jest, of course.  Hopefully.

Geographical Range

Ergaster/Erectus not only made it out of Africa, they spanned the whole of tropical and subtropical Eurasia, as far north as France in the west and Beijing in the east.  I haven’t heard about any Erectus discoveries further north, or in the Western Hemisphere at all.  This suggests to me that they hadn’t yet developed technology needed to survive in a cold climate—for example, fur clothing or reliable control of fire.  Of course, such technology would have been a prerequisite for entry into the Americas, which they appeared not to have done.

In the south, as I’ve already mentioned, Erectus definitely made it as far as Indonesia.  Now, the way I see it, if they made it to Indonesia, there’s nothing that would have prevented them from reaching Australia; but we can’t be sure.  Australia has yet to yield any Homo remains dating from before the arrival of modern humans around 65 KYA(3). 

Fire and Other Technology

As I say, the inability of Erectus to expand its range to the north suggests to me that they did not have things like warm fur clothing or the reliable control of fire.  It does appear, however, that Ergaster/Erectus had occasional access to fire.  We have pretty good evidence for controlled fire in South Africa around a million years ago (4).  Southwest China has yielded blackened mammal bones dating to 1.7MYA, although that doesn’t necessarily mean that the fire was anthropogenic.  Over the course of Ergaster/Erectus’ existence, brain volume increased substantially, which has led some experts to suggest that easily-digestible cooked meat was available.  The excellent PBS documentary Becoming Human talks about how fire and cooking could have led Ergaster/Erectus to become more social—e.g. by sharing fires for cooking and warmth.  At any rate, fire use would have been a very gradual process.  Perhaps it could have begun with discovery of embers in the wake of wildfires, which led to fires being maintained over long periods of time.  If you’ll allow my imagination to step in here for a moment, we may even have a faint psychological memory of a “fire-carrying” past, before fire could be reliably created, in ceremonies like the Olympic torch.  Even recently, indigenous populations in wet climates like Tasmania preferred to carry coals from one campsite to another, so that they didn’t have to go to the trouble of finding dry wood for a new fire(5).

Finally, it’s very worth mentioning that Ergaster/Erectus may also have been the first human ancestor to travel by sea.  Heading back to Indonesia, we find evidence of Erectus habitation from 900 KYA.  Although most of Indonesia was, at the time, linked by a land bridge, there were still some areas that were cut off by water—the  island of Flores, for example, whence comes the 900 KYA figure(6).  It seems plausible that Erectus was able to put together simple rafts that allowed them to reach this remote island—and to discover that even here, they were not alone.  But we’ll get to that later.

As far as the Ergaster/Erectus toolkit is concerned, we see an interesting new technology emerging in their wake: the Acheulean industry, a toolmaking tradition that spanned a mind-boggling 1.7 million years, from about 1.8 MYA to 100 thousand years ago.  Typifying the Acheulean tradition are what we call the “hand-axe”.  These tools, to me at least, are remarkable not just for their practicality, for their rough beauty.  Let’s take a look:




  
I’m no flintknapper, but I think it’s very important to note the symmetry that we see with these tools, as compared to the earlier Oldowan industry.  To me this suggests greater planning ability: these tools were made with an end result in mind.  Unlike Oldowan tools, Acheulean hand axes were sourced from high-quality material, often at a distance of several miles from where they were found.  Their owners invested significant time and effort into their creation, and probably kept them for some time.

Looking at these beautiful tools, I can’t help but wonder if there could possibly have been an aesthetic element to their creation.  Surely their symmetry and ease of handling had a practicality to it, but there must have been something more.  This “moreness” becomes most evident when we compare these artifacts with the crude pebble tools of the Oldowan industry.  Indeed, the Acheulean hand axe may have been a catalyst for the birth of human aesthetic sensibility as we know it.  Could we be witnessing—dare I say it—the birth of Art?

Art and Abstraction

If indeed the Acheulean knappers had some primitive aesthetic sensibility beyond the mere utility of their artifacts, that’s a huge jump forward, and in a way, the birth of human consciousness itself.  Abstract imagination is what sets us apart from the animals in a way that nothing else does.  From these tools, we can already see that Ergaster/Erectus was able to sit down with a rock, visualize a hand-axe, and turn that visualization into a reality.  That’s powerful stuff, and at a very visceral, “gut” level, that must have been almost traumatizing in its immensity.  It must have taken thousands of generations to work through—imagine!  You have this picture in your mind—and at this time, neither the concept of a picture nor the concept of a mind existed.  It was only there as potential, and then you recognized that potential and made it into a physical reality.  I’m no philosopher, as you can probably tell, but…wow.  Imagine experiencing that and trying to work through it with your friends and family, some of them getting it, some of them not…and, generation by generation, the number of those “getting it” gradually getting larger.

Toward the end of Erectus’ tenure, we see some tantalizing glimpses of what may have even been art, or at least abstract symbolism, in the proper sense.  In Indonesia, at the remarkable Trinil Erectus site, there was a seashell discovered that had carved into it this beautiful zigzag pattern.

 (7)

Now, this doesn’t look like much, and you may roll your eyes when I call it beautiful, but it is!  Just think: this is an original abstract pattern from five hundred thousand years ago.  This is the birth of art!  Now, the question is, were these absentmindedly scratched onto the shell—that is, a doodle—or was it more deliberate?  In other words, was this the prehistoric equivalent of you drawing spirals and zigzags in the margins of your math textbook?

There appears to have been some genuine effort that went into this item—after all, it’s much more difficult to carve a pattern into a hard surface than it is to doodle on paper.  However, I’m not sure that means the pattern had a special significance.  Here’s what I imagine happened: some Erectus—let’s name him Lucas—was sitting around camp one day, processing shellfish.  His task complete, Lucas got bored, and amused himself by scratching a cool zigzag pattern onto one of the shells.  It was cool and interesting because first it went up, then it went down.  And then up again!  Wowie!  How pleased with himself he would have been!  His line went up and down!  He then gave it to his girlfriend as a romantic gesture.

Now, I’m kind of having a laugh at the poor guy’s expense, but if you think about it, by Erectus standards a zigzag doodle would have been a pretty big deal.  And Lucas wasn’t the only one!  The Bilzingsleben Site in Germany(8) has these enigmatic engravings on an elephant tibia:


I always get chills when I look at these radial lines engraved onto the bone.  Clearly this wasn’t an attempt to scratch the meat off of the bone or to get the marrow; these marks were made for their own sake.  Some people are calling this a potential calendar, or a ruler, or even a protractor.  I don’t know about all that.  Regardless the critical fact here is that someone sat down, imagined lines engraved onto the bone, and then made them.  For these early creatures, bringing the conceptual into physical reality must have been an almost mystical experience. 

The Bilzingsleben finds are dated to about 370 KYA, and the bones found there are classified as E. erectus--that surprises me a little, since that’s a very late date for H. erectus in Europe.  For the most part, we see H. erectus being phased out in Europe by around 600 KYA or so by the more modern H. heidelbergensis.  Still, I assume that the professionals know better than I do, so I’ll buy it. 
Regardless, in my view, which exact species made these engravings is a technical point, the relevancy of which pales in comparison to the cognitive development that’s demonstrated by these engravings.  Even a chimpanzee would never do something like that by itself.  But here we have a pre-human creature conceptualizing a geometric pattern, and then working it into a physical reality.  Whether or not it carried some symbolic meaning, this is a huge step.  When considered together with the hunter-gatherer societies formed by these creatures, the Trinil shell suggests to me that these creatures were much closer to us in behavior than to chimpanzees, australopithecines, or even H. habilis.  Would they have understood, say, the concept of time?  I doubt it, since ideas like that must have come around very slowly over thousands of generations with herculean mental effort.  But on the other hand, they amused themselves by doodling, which is perhaps just as monumental.

Before I move away from the Bilzingsleben finds, I would like to mention one other cool discovery that may well have to do with the increased cognitive aptitude of late H. erectus: the skulls that were found at this site appeared to have been smashed in…postmortem.  That is, these individuals were already dead when they had their skulls smashed.  Now why would you do that to someone who’s already dead?  Incredibly, we may be seeing evidence of some sort of funerary ritual.  Think about it: if you don’t want your friend coming back as a zombie, what do you do?  It sounds ridiculous, but I’m really only half-joking here.

Could They Talk?

While we’re on the topic of abstract symbols, let’s talk about whether Ergaster/Erectus was able to talk.  Language is inherently symbolic—after all, if I say the word “cat”, there’s nothing about that word that is inherently cattish, and you wouldn’t know what it meant unless you were “initiated” into the language club. 

Physiologically, there is some controversy.  Two parts of the body most intimately connected with language are the vertebrae, which reflect vocal capability, and the Broca’s area of the brain, which controls speech production.  Turkana Boy’s vertebrae, when examined, show that he could probably not have produced the same speech sounds as we can.  On the other hand, the older Dmanisi finds show not only humanlike vertebrae, but also the presence of a Broca’s Area(9).  But even if they could speak, did they?  I doubt that they woke up one day and suddenly began making sentences in the third conditional.  I like to think that they did have what we would call words, but they were used only in short utterances, in the strictly physical and pragmatic realm.  It probably started out as a series of nouns, since “cat” is an easier concept to grasp than “go” (Going where?  Who is going?) or “bad” (What happened?  Why is this bad?).

I also like to think that sooner or later they must have started naming each other.  For example, if I my brother has a big nose, I could call him Nose.  If my friend likes eating berries, I could call him Berry.  Simple things like that.  Of course, this is all in my imagination, and I’m certainly no neurolinguist, but it could well be during the ergaster/erectus era that this stuff began to happen.

Conclusion

So, that's my whirlwind overview of H. ergaster/erectus.  What do you guys think?  Are my imaginings too fanciful, or could have some of my hypotheses been accurate regarding their behavior?  Tell me your thoughts.  Next time we'll talk about the guys who phased out H. erectus in Europe: Homo antecessor and Homo heidelbergensis.  See you then!

No comments:

Post a Comment