Saturday, October 31, 2009

232. The Baseline Scenarios -- part 8:Conjure

From the Merriam-Webster Dictionary:

transitive verb 1 : to charge or entreat earnestly or solemnly
2 a : to summon by or as if by invocation or incantation b (1) : to affect or effect by or as if by magic (2) : imagine, contrive —often used with up
(3) : to bring to mind —often used with up.

I am now ready to conjure! As you can see, I have nothing up my sleeve, and my hands are tied:

Before continuing however, there are a few important points I'd like to make:

1. It has been my intention in all my research to base all hypotheses on evidence, and logical inference directly based on evidence, rather than assumptions. Since so many anthropologists and archaeologists routinely make assumptions, the difference might not be obvious, but it is real and as far as I'm concerned it is all important. For example, I am not simply assuming that certain Pygmies and Bushmen share certain basic cultural attributes with their "Stone Age" ancestors. Assumptions of this kind about hunter-gatherers have been made many times in the past -- and they have also been attacked, and rightfully so, as "myths." I see it as my responsibility to ground all such hypotheses in real evidence, not just suppositions that might seem reasonable, but in fact cannot be supported by anything more than conjecture.

2. Since I've been challenged on this point by a regular commentator on this blog, German Dziebel, I am willing to concede that my acceptance of the mainstream population genetics research, and the associated Out of Africa model, can be seen as an assumption, because this model, though based on a considerable body of evidence, has not yet been fully verified, and there are in fact certain inconsistencies that have not yet been accounted for. Moreover, there are alternative theories, one of which, an Out of America theory, has been presented by Dziebel himself. Those who, like him, remain suspicious of the Out of Africa model, should feel free to regard HBP as the common ancestor of the Pygmies and Bushmen only, rather than all living humans, as implied by the mainstream research and the phylogenetic trees based on it. To put it another way, to the extent that we can regard Out of Africa and the genetic research behind it as having been established with a high degree of confidence, we can accept HBP as, in all likelihood, representing the common ancestor of all living humans; to the extent that this model remains in doubt, the status of HBP will also remain in doubt. As far as I am concerned, the evidence in support of Out of Africa is overwhelming, and I am going to proceed on that basis. If this is an assumption, then so be it. It will be my only assumption -- and if I violate my promise in this regard I have no doubt German will call that to my attention.

3. My primary intention is to open up possibilities for research and exploration rather than establish incontrovertible facts. The method I'll be using, based on what I've called "triangulation," should be seen primarily as a tool -- a kind of observatory if you will, for probing human history. In many cases there will be certain things that can be established and others that cannot. Where something cannot be established with certainty, that should be understood as a basis for future research. In any case, the "triangulation" method must always be balanced by a healthy dose of critical thinking.

For example:
As we've already learned, within the three populations under consideration, EP (Eastern Pygmies), WP (Western Pygmies) and Bu (Bushmen), some groups hunt primarily with poison-tipped arrows and others with nets. Interestingly, we find net hunters within both EP (Mbuti) and WP (Aka), while those that hunt primarily with bows and arrows can also be found in both tropical forest regions. No Bu group, to my knowledge, hunts with nets. Despite such discrepancies, however, further research reveals that poison arrows are in fact used for hunting by groups from all three populations, EP, WP and Bu. While the Aka and Mbuti use nets as their primary hunting tool, they use poison arrows from time to time as well. Therefore, regardless of the net evidence, the presence of bows and arrows equipped with poison in all three major populations completes our triangulation and thus makes hunting with poison-tipped arrows a very strong candidate indeed for inclusion in HBC. Note, by the way, that the discrepancy in the use of nets and bows for hunting, which for Hewlett amounts to an important cultural difference among Pygmy groups, has no bearing on our triangulation method, which depends only on the presence of certain traditions, not their relative degree of importance in recent times.

However: bows and arrows are commonly found among a great many peoples worldwide, including many of the Bantu groups that have had contact with Pygmies and Bushmen for a very long time. And there have been reports of the use of poisoned arrows among such groups. Our method is therefore not strong enough in itself to establish the use of such weapons among HBP, because the Pygmies and Bushmen might have learned this technology from their non-forager neighbors . Our method is strong enough, however, for us to zero in on the use of poisoned arrows as a very reasonable hypothesis, which can in fact be tested. What non-forager groups in Africa are known to have used poison arrows, and what historical evidence exists that might tell us whether this weaponry was taught to Bantus by foragers or to foragers by Bantus? Is there any archaeological evidence pointing strongly to the use of such weapons in either the forest or southern Africa prior to the Bantu expansion of ca. 3-4 thousand years ago? If convincing evidence can be found that the Bantu groups learned to use poison arrows from Pygmy and/or Bushmen groups, that would point very strongly to the use of such weapons by HBP and we could at least provisionally accept this technology as a part of HBC. If no such evidence can be found, or if it is determined that the Pygmies and Bushmen learned it from their neighbors, then either it was not a part of HBC or its status must remain indeterminate.

(to be continued . . . )


German Dziebel said...

Arrow poison is known in such an African refugium as Kordofan, where no Pygmies or Bushmen are found. The Madhibans, the hunting clan among the Somalis, used arrow poison. Again, you can't attribute it to Pygmies. There is a dozen of botanical species across Africa used as fishing and hunting poison. Arrow poison is known in South America, India, Siberia, Papua New Guinea. It could safely be reconstructed for HBC, with roots anywhere in the world, even if Pygmies and Bushmen didn't exist.

DocG said...

You see what I mean, ladies and gentlemen? Exhibit A: yet another anthropologist making assumptions. Happens all the time.

German, you should be paying me for the education you are receiving on this blog. :-)

You assume it would somehow make a difference if poison arrows are found among other hunter-gatherers. Why? The Hadza too use poison arrows. So what?

If HBP used them, then we'd expect to find them among at least some of their descendants, no? And surely the Pygmies and Bushmen are not their only descendants. According to the genetic picture for Africa, the Kordofans, Madhibans, Somali hunters and Hadza would also be their descendants, no? And if OOA is correct, then it's not surprising to find them in S. America, India, Siberia, etc. as well.

That's not the issue. What's important is not whether other groups use them, but whether this technology could have been passed on to the Pygmies and Bushmen by groups with which they are known to have had relatively recent contact, such as certain Bantu groups. If there is no evidence of that, then we have to ask ourselves, how did the EP, WP and Bu get their poison arrows -- and when? And if you rule out HBC, the answer isn't easy. But perhaps you have some thoughts on this?

German Dziebel said...

Victor, you won't be able to find answers to these questions. No scientific discipline will ever be able to retrieve intercultural borrowings in the absence of written sources. Linguistics could trace words denoting arrow poison across all African languages, some forms may recur but which way and when a borrowing took place is beyond the radar of any linguistic methods. In any case, the history of words won't be the history of objects.

Convergence through functional adaptation (whether as a retention or as an independent innovation) is the best way to explain poison arrows throughout the world. There're cases when you don't need "common descent" to explain worldwide parallels in technologies. Only very specific forms can be used. For instance, the Ainu use fluting on their arrow points. This is a very specific technological detail, only known in Clovis and Folsom projectile points in America. It could be result of diffusion or common descent but not convergence. If you encounter such a specific match in arrow poisoning inventory among Pygmies and, say, among Somalis, you could start thinking about borrowing vs. common descent. But in the absence of such, convergence is the easiest explanation.

In evolutionary biology, arrow poison would be classified as plesiomorphic and hence useless for cladistic purposes. Only shared synapomorphies can be used to infer common descent.

My consultation is always free.

DocG said...

OK, German, good. We are now finally on the same page, i.e., talking the same language (more or less). This is an excellent response.

"No scientific discipline will ever be able to retrieve intercultural borrowings in the absence of written sources."

Strictly speaking this may be true, but a similar objection could be applied to a great many other scientific hypotheses, many of which are widely accepted. As I see it, when in doubt, apply Occam's Razor. If the distribution of a given feature is more simply explained by common descent than convergent evolution, AND THE AVAILABLE EVIDENCE FAVORS NEITHER HYPOTHESIS, then, according to Occam's principle, descent from a common ancestor is to be preferred.

It's important to understand that this does NOT mean descent has been proven. All it means is: "pluralitas non est ponenda sine necessitate ("plurality should not be posited without necessity")." Convergent evolution implies a plurality of explanations, i.e., independent inventions, in each and every different situation, whereas descent requires only one, and thus there is no necessity, ALL ELSE BEING EQUAL, for positing the former. The fact that most anthropologists tend to favor independent invention nonetheless is a reflection of the bias that has built up over the years against the notion of "survivals." Independent invention is nevertheless an assumption, NOT a hypothesis based on either evidence or scientific principle.

This does NOT rule out the possibility that in certain cases poison arrows might have been independently invented, and where there is evidence for that such evidence must be respected. Where there is NO evidence, however, the simplest explanation is to be preferred. Again this is not a matter of true or false, because science can never establish any theory as absolutely true. All it can do is posit testable (i.e., falsifiable) hypotheses -- and then proceed to test them against the currently available evidence, which is what I am proposing.

As far as written sources are concerned there are in fact a great many such sources that might well enable us to falsify common descent. All we really need is solid evidence that some non-forager group taught some pygmy or bushmen group how to make and use arrow poison.

"Only very specific forms can be used. For instance, the Ainu use fluting on their arrow points. This is a very specific technological detail, only known in Clovis and Folsom projectile points in America. It could be result of diffusion or common descent but not convergence."

Yes, the more distinctive any feature is, the more likely it is to be inherited or borrowed rather than independently invented. Which is why I feel so strongly about the musical affinities.

This should encourage us to investigate the bows and arrows and poisons used by EP, WP and Bu to determine how distinctive they are and whether the same distinctive traits are found in all three populations.

German Dziebel said...

Common descent is not always the simplest explanation. In phonology, most patterns with irregular but worldwide distributions are considered to be independent inventions. See Evolutionary Phonology, by Juliette Blevins. The burden of proof is on you, as the scholar who argues for common descent with ancestral forms concentrated among Pygmies and Bushmen. As in the case of recombination in DNA, there're cultural forms that can't be used to infer prehistory. Arrow poison is one of them, unless you develop a typology of those in which certain formal properties of the "arrow poison complex" will be too unique and unmotivated adaptationally to infer either common descent or borrowing. Once you develop this kind of typology, if it's there in the first place, you can apply Occam's Razor to adjudicate between borrowing and common descent.

DocG said...

I am basically in agreement with your last post, German. However . . .

German: "Common descent is not always the simplest explanation."

Common descent always involves fewer "entities" than independent invention, so as far as Occam's Razor is concerned, it IS always the simplest explanation. However, the simplest explanation does not satisfy Occam unless it is also at least as consistent with the evidence as any alternative.

"In phonology, most patterns with irregular but worldwide distributions are considered to be independent inventions."

I suspect that this is because independent invention is more consistent with the evidence than common descent, not because it is the simplest explanation.

"Once you develop this kind of typology, if it's there in the first place, you can apply Occam's Razor to adjudicate between borrowing and common descent."

If what you are saying is that we need first to investigate the different types of arrow poison and how they are used in each case, I agree.