Thursday, August 2, 2018

Cavemen Rock, Part VII: Stay off My Lawn




Hello again friends, welcome back to Office Hours with the Brofessor, the Show that’s Proudly Irrelevant.  Today we’re continuing Cavemen, but I’m changing the name.  The new name of this series is “Cavemen ROCK,” since, obviously, rocks, cavemen, ha ha ha.  It’s so obvious, I don’t know why I didn’t think of this.  Even now, my friend suggested this to me.  Oh well.

Anyway, let’s move on.  We last talked about the species known respectively as Homo ergaster and Homo erectus in the context of African and Asian assemblages.  I’ve also hear the expression “African H. erectus” used, but I’m not sure what the difference is here with H. ergaster.  If you know, please tell me!

Ergectus, as I’ve recently taken to calling them, held on from almost 2 MYA until well into the last five hundred thousand years—maybe even as recently, relatively speaking, as 150 KYA.  During time we have seen the emergence of true hunting and gathering, sporadic fire use, and maybe even primitive seafaring.  We also see the very first glimmerings of human consciousness as we know it: care for the elderly and infirm, family units, and maybe even a sense of the aesthetic in their wonderfully knapped hand axes.  According to Iain Davidson at the University of New England, by the ergectus era our ancestors were able to control our vocal utterances independently of our emotional state(1)—and, indeed, the vertebrae of the classic Turkana boy specimen show humanlike vocal capabilities.  These creatures may have had names for the things around them, or even had names themselves—though I doubt they had anything close to what we would call “articulated language”.

Still, as with H. habilis, I don’t think we could have interacted with ergectus the same way we interact with each other.  Although, as evidenced by Grandpa George and Turkana Boy, that they cared for infirm members of their own groups, they probably hadn’t yet mastered the art of not tearing each other apart when meeting new acquaintances—this will factor in today’s discussion, so keep that in mind. 

It was into this milieu, around 1.2 million years ago, that one European strain branched from the ergectus lineage.  Unlike ergectus, these guys had more humanlike facial features, especially in, according to Smithsonian Magazine, “the shape of the nasal region and the presence of a facial depression above the canine tooth called the canine fossa”(2).  That sounds like a small difference, but these features are more gracile than those of ergectus.  These creatures, attested from the Atapuerca Mountains of Spain, were christened Homo antecessor, or “Pioneer man”, by modern science.

Atapuerca is an important site, so let’s familiarize ourselves with the area.  This is a mountain range in Northern Spain, although to be honest, it looks more like a hill to me.  Maybe the name comes from Don Quixote’s fevered imagination:

“Behold, Sancho!  Mountains, soaring up to the heavens!  Surely, these peaks must hide the secret of Dulcinea’s enchantment!”

Or, maybe I’m just a snob, being as I am from the heart of Colorado’s majestic Rocky Mountains!  At any rate Atapuerca has a number of sites stretching across prehistory, from the lower Paleolithic to the Bronze Age.  The finds here are quite remarkable for their diversity of time depth!

H. antecessor, documented from this site, was present between 1.2 and 0.78 MYA.  Behaviorally and technologically, they appear not to be markedly different from their ergectus brethren, in that their tools are a continuation of the Acheulean industry(3).  We can tell by examining their teeth that they subsisted on tough, difficult-to-chew foods (4).  This implies that, like H. erectus, they did not have (regular) access to fire.  There is little else we know about antecessor’s behavior, apart from one more point that I’d like to bring up now.

In fact, this is a bit of an elephant in the room.  I don’t want to spend too much time on this, because it’s not that big of a deal, and it’s not very nice to think about.  Here goes: the bones of some antecessor specimens had had the muscles removed with stone tools, before the bones were scattered among those of game animals.  The implication is that these individuals had been hunted, butchered and eaten by other H. antecessor.

I know, I know!  That’s disgusting, and I hate to even mention it.  Also, it’s annoying to talk about because this stuff gets heavily sensationalized by non-academic media.  There’s this deeply-ingrained disgust we feel at the idea of cannibalism, be it survival, mortuary or otherwise.  So that’s what the non-academic press likes to jump on, I guess as a kind of clickbait.  We also see it in caveman movies, from “Quest for Fire” to “The Thirteenth Warrior”.  I don’t know why it’s such a big deal in our popular perception of cavemen, but there it is.  It may be related to the racist image of the “cannibal savage” used to justify Western imperialism during the Age of Exploration.  That is to say, focusing on this behavior among our ancestors may be a way of distancing ourselves from them and making them out to be inferior to us.  I don’t know, and it’s a gross, strange thing for everyone to dwell on as much as they do.  I wouldn’t have mentioned this point at all, if it didn’t have an important implication for behavior.

First, eating these guys appears not to have been ritual or funerary behavior, which is unsurprising, since the mind of H. antecessor probably wasn’t quite there yet.  We know this because the bones were treated exactly the same as those of game animals.  So, what exactly happened here? 
One easy explanation is that if one of your bros keels over and dies, eating him is kind of a convenient thing to do, since it gets rid of the body and you guys don’t need to go hunting that day.  You can stay home, crack some cave-brews and play Cave Mario Kart.  That’s possible, but why don’t we see evidence of this with, say, Grandpa George or Turkana Boy?  Did H. erectus not connect the dots that far?  Furthermore, I have yet to see evidence of pathology in the bones of these individuals.  That doesn’t mean they didn’t die of illness or injury, but there’s no published evidence thereof from the fossil remains—which we have with Grandpa George and Turkana Boy.  The latter was old and weak, and the former died from an infection.  Neither was cannibalized.  That said, H. antecessor is almost a million years, and thousands of miles, removed from Grandpa George and Turkana Boy, so perhaps it’s not appropriate to bring them into the discussion.

Another possibility is that there was a famine or something, and there was that thing that happens in cartoons where they looked at each other and their buddies turned into talking steaks.  But by all reconstructions, the environment of the time wouldn’t have made a very difficult place to live(5).  That said, there’s always the possibility of a lean season.

Let’s look again at the individuals that became dinner.  Examining the butchered remains, we realize a commonality shared by the victims: these individuals were children, as young as ten years old.  Again, disgusting and disturbing, I know, sorry.  But that fact is important because we see a parallel behavior among chimpanzees: male chimps, when patrolling their territory, will kill and eat infants that they come across(6).  We could be seeing a similar behavior here.  The juvenile H. antecessor specimens that were eaten could have been members of an out-group encountered by adult males on patrol. 

One problem with this scenario is, of course, that ten years old isn’t exactly an infant, unless we’re  speaking French.  Indeed, we know from other specimens, one of them being Turkana Boy, that archaic hominins reached adolescence faster than kids today.  Turkana Boy was eight when he died, but had adolescent skeletal morphology.  H. antecessor was about 800 thousand years after Turkana Boy, so even if the rate had slowed somewhat in the intervening time, it would still be reasonable to guess that a ten-year-old antecessor might have already entered adolescence.  In that case, this situation would differ even more from that of modern chimpanzees, since killed infants of outgroups are eaten, but for some reason killed adults are not—at least, such behavior has not yet been observed.  For this reason, it’s important not to discount the in-group death or famine hypotheses.  Still, the “Patrol Hypothesis” seems to me to be the most probable, or at any rate the least improbable.  That is to say: the cannibalized H. antecessor remains found represent the same phenomenon observed among male chimpanzee patrols.  This has serious implications for our attempt to reconstruct H. antecessor behavior.

If in fact the Patrol Hypothesis is true, it provides a serious counterpoint to the various baby steps we’ve seen in the progression toward modern behavior.  We’ve seen ergectus care for its elderly and sick, knap symmetrical tools, probably use fire, and very possibly use rafts and simple word-like utterances.  But for all that, the discovery of these poor kids demonstrates starkly that raw animal instinct still had a heavy influence upon these creatures, at least in terms of their dealings with out-groups.  Deep down, they were in many ways quite far from “human” in terms of cognition. 
Do you remember way back at the beginning of this series, probably a year ago now, when I talked about a mark of “peopleness” as being morally responsible for your actions?  If the Patrol Hypothesis explains this incident, Homo antecessor and its ergectus predecessors were not morally responsible for what they did.  Chimpanzees don’t think about cannibalizing the infants that they kill on patrols, they just do it.  In the same way, they don’t think about not cannibalizing the adults that they kill.  It’s simply something that’s hardwired into their brains, and may have been hardwired into the brains of early Homo. 

How could we test if the Patrol Hypothesis is true?  We would have to look at other fossils of the same time period and before, with a special eye toward both juvenile bones and those which show evidence of having been butchered.  If there is an overlap, perhaps this hypothesis is worth considering.

So, here’s what I think happened: one day, some H. antecessor males were walking around on patrol.  They knew that there were other groups in the area, with whom they occasionally clashed in conflicts not unlike those between modern chimpanzee troops.  Along they came, minding their own business, when in the distance they saw some punk kids skateboarding on their driveway—or the Lower Paleolithic equivalent.  The kids knew that they should stay off the other group’s territory.  However, they were acting with the same rashness and impulsiveness characteristic of today’s twelve-or-thirteen-year-olds, and they paid the price.  The patrolling males ran them down, killed them, and ate them without really considering what they were doing.  They acted entirely on impulse.  Had the victims been adults, the patrol would have simply killed them and left the bodies, but juveniles, for whatever evolutionary reason, triggered a different response.  Whatever explanation this behavior had, it is the same thing that we observe today among chimps.

So, to sum up: here was a creature that was capable of touching tenderness toward members of their in-groups, but remained quite aggressive toward members of out-groups.  Which, if you think about it, is quite human in a way!  Goodness knows that we have enough trouble with racism and xenophobia in our time.  But, unlike them, we have gained the amazing ability to think through our actions, and consciously decide to cooperate with members of out-groups, rather than instinctively kill them.  I think there’s a lesson here for us today—when we give in to prejudice toward those who might not be in our “tribe”, we are stooping to the same level as H. antecessor all those years ago!

In my discussion of Grandpa George and Turkana Boy, I talked about how these two cases demonstrate how the goodness of humanity predates “humanity” itself.  Well, the antecessor finds show us that humanity’s bad side goes back a long way too.  So, to any Paleolithic kids out there: stay off Old Man Antecessor’s lawn!