I’ve returned more than once (including in song) to the theme of tetrapod pentadactyly, because it opens up structuralist and other non-Darwinian aspects of evolution to consideration. A close runner up for my interest is the case of the giraffe (no song on that, so far), because it was an icon of Lamarckian evolution that became an icon of Darwinian evolution – before both tales were shown to be mere folk-tales by the actual study of giraffes: the long neck cannot possibly be explained by access to high sources of food, either by Darwinian selection or Lamarckian acquisition.
That story is also told in this excellent downloadable short book by Craig Holdrege, an associate of Stephen Talbott, mainly as a mea culpa for the way when, as a teacher, he obeyed educational directives by spinning kids these two cock-and-bull yarns to confirm the truth of Darwinism over Lamarckism. However he goes well beyond iconoclasm to reflect on the giraffe, and its evolution, seen in holistic terms. In some ways this study is illustrative of the problems with most current approaches to evolution, and especially the ruling Darwinian paradigm.
Holdrege points out how the typical evolutionary story works. A particular trait is chosen (eg the giraffe’s long neck), a specific function for it is selected (reaching food), and the two combined by an imaginary explanation from the narrow perspective of how it contributes to survival:
Both the trait (“long neck”) and the particular survival strategy are products of a process of abstraction from a complex whole. Therefore we can think them clearly and establish a clean and transparent explanation that seems to work — it makes sense that the long neck evolved in relation to survival and feeding habits. Unfortunately — and it is the price we pay when we operate with abstractions — we have lost the giraffe as the whole, integrated creature it is. We’re not explaining the giraffe, we’re explaining a surrogate that we have constructed in our minds. The animal has become a bloodless scheme. For this reason evolutionary stories are usually woefully inadequate.
The abstraction element reminds me of Arthur Eddington’s more general complaint, coming from physics rather than biology, of how materialist science describes the world whilst simultaneously discarding its reality and substituting mathematical abstraction. We should pay attention to these recurrent themes.
Holdrege, considering the giraffe-in-itself from his own (and others’) study in the field, shows how the long neck cannot be isolated from the unified character of the whole animal, its approach to life and even its environment. There is something specifically “giraffish” pervading the whole organism (remember what Arthur Jones learned about cichlids here?) For example, why should feeding be isolated from other reasons for the beast’s long neck? Such as this…
Incidentally, evolutionary convergence might predict the same kind of behaviour in sauropods – that would have been thing to see – and hear! Maybe that’s why they kept their brains so small.
After dealing with the actuality of giraffes, he discusses their evolution, raising (rather than seeking to explain it theoretically) the lack of intermediate forms in the giraffe family, and related intriguing phenomena (quite general in biology, apparently) like the threefold division between the branches of that family – the extinct massive cattle-like types, the tall giraffes and the intermediate okapis and their extinct relatives. Why should such distinctions occur, with neither intermediates nor precursors in the fossil record? He doesn’t attempt exhaustive answers, but does call for a more animal-orientated, rather than genocentric and adaptive, approach. In so doing he points out (as many others have) how narrow we have made our alternatives nowadays:
The idea that organisms evolve began to take hold of human minds in the decades before and after 1800. This spurt in interest was not because a wealth of new evidence for evolution was suddenly laid out. Rather, individual thinkers and scientists began viewing geological, biological, and historical processes in terms of development and transformation…
This revolution in human thought was not bound to any particular theory… Differing views of evolution arose, depending on the perspective of the individuals. Some were spiritual, others materialistic; some were teleological, others emphasized randomness; some placed structure in the foreground, others function.
But now:
…when we hear the term “evolution,” think immediately of the Darwinian theory of evolution: random mutation and natural selection drive the evolution of species. We probably don’t even know that there always have been and still are other ways of interpreting evolutionary phenomena. In the United States, it seems, one must be either a Darwinist or a Creationist (i.e., someone who doesn’t believe in evolution). Recently some scientists have propounded what they call “intelligent design” as an attempt to wed spiritual and evolutionary views (see Meyer 2004); they are, by and large, pushed into the creationist camp by Darwinians. The battle between Darwinists and Creationists, fought on both sides with religious fervor, has led to unfortunate oversimplifications and to an unwarranted polarization of perspectives. This dichotomizing is, to my mind, counterproductive and shuts down our thinking about some of the true riddles of evolution. (p73-74)
I would suggest that a symptom of that “oversimplification” is the Evolutionary Creation project. The “science” which is being held up as compatible with “faith” is largely culture-bound to the narrow perspective of Darwinism, when there is so much more in heaven and earth. One aspect that intrigued me in Holdrege’s treatment was the giraffe as part of the “superorganism” of its habitat, as the real subject of evolution. And that in terms far wider than the Malthusian struggle for survival – surely of great relevance in formulating a theory of theistic evolution. After discussing the remarkable physiological changes that affect acacias when browsed by giraffes, and the similar relationships with acacia-dwelling stinging ants, he writes:
When we view thorns and ants exclusively as defensive mechanisms, we assume the acacia and the giraffe are antagonists, each busily shaping the survival of its own species. We view species as separate entities that interact on the basis of competition. But species are not separate entities; every species lives from and provides life to many other kinds of organisms. When we view species interaction in terms of coexistence, where each species, through its own life, supports the life of other species, we transcend the narrow terms of competition and individual species survival that constrain so much of ecological and evolutionary thought today…
In conceiving abstractly of discrete organisms, we think of giraffe and acacia as separate entities, which of course they are physically when the giraffe is not feeding. But the fed-on acacia is not the same after giraffe browsing. It may form more and longer thorns, but it may also produce longer shoots, take more minerals out of the soil, and form nutrient-rich substances in its leaves, while suppressing leaf-aging as indicated in less tannin formation. In this way the giraffe has become part of the acacia. Then, when it feeds again, the giraffe feeds on something that is connected to its own activity. The apparently clear boundary between organisms dissolves, and we are led to picture organisms as participating in each other, rather than standing next to each other. We can only truly understand the giraffe when it is viewed as part of this concrete web of life.
Such a view of course makes it impossible to tell simple stories about tall giraffes reaching higher in droughts. But as St Paul says, in the context of God’s Kingdom of right relationships: “When I became a man, I put childish ways behind me.”
“…raising (rather than seeking to explain it theoretically) the LACK OF INTERMEDIATE FORMS in the giraffe family, and related intriguing phenomena (quite general in biology, apparently) like the threefold division between the branches of that family – the extinct massive cattle-like types, the tall giraffes AND THE INTERMEDIATE okapis and their extinct relatives.”
Quite right, Lou – very poor wording.
The illustration is this which demonstrates the point quite well, and the wording should read something like “lack of transitional forms” and “the more ‘generic’ okapis and their extinct relatives”.
The original source also mentions the not-uncommon lack of obvious phylogenetic precursors to the three clear divisions in the fossil record.
But we shouldn’t necessarily expect a full set of living intermediates, as you know. It’s the fossils that should get more similar as we go back in time. I can’t speak to the fossil record of this group, but in this case even the living animals do seem to contain some intermediates; the okapi does seem to be somewhat intermediate between the bulky ones and the gracile giraffe.
The claim that there is a general lack of intermediates is
grossly misleading. There are lots of clear fossil transitions between a common ancestor and a pair of highly divergent living groups. Cats and dogs, mammals and reptiles, whales and artiodactyls, etc. There are lots of gaps of course, that’s what we should expect from a spotty and possibly selective fossil record, but the gaps only get smaller as time goes on.
Instead of “artiodactyls” I should have said “traditional artiodactyls”…
That sounds OK, except that when I think of “traditional artiodactyls” I think of this.
It’s truly a question of interpretation. There would be no theory of punctuated equilibria if the pattern of stasis and saltation didn’t occur in the fossil record.
Remember David Raup in 1981:
A phenomenon. Best explained by paucity of fossil record, or by events on the ground, and if the latter what? That’s the question the author raises, like many before him including, of course, Charles Darwin.
In this case the issue is less gradualism per se, but the clear division of the fossil record into quite separate groups. Clearly if you take ANY three related (or even similar) groups one can be deemed intermediate – indeed, one must be intermediate by certain criteria.
For example – a bicycle, the Wright Flyer, and the Apache helicopter. But there is no gradual transition between any of them, even if the Wrights learned their engineering on bicycles.
In the context of the author, who is proposing evolution but Goethian rather than Darwinian, a better example might be, say, the Mercury, Gemini and Apollo spacecraft. One was developed from the previous one, but there were no intermediates.
A (non-science) teaching colleague once shared with me that he hated it when, in high school, his physics teacher would say “… and we’ll ignore air friction …”. His dislike was that the problem posed became much less real to him since it was now necessarily a hypothetical situation. I didn’t have time in the hallway to carry that discussion further, but if I had, I would have brought up the point that taking air friction into account requires the application of differential equations just to complete a simple free fall problem. (and even then it still requires idealization of some sort such as ignoring air currents, changing atmospheric densities with height, etc; so even for all this effort, one is only *closer* to truth; and hasn’t arrived). Most high school students are doing well to simply master the Newtonian mechanics involved before they are ready to ascend the stair case to account for the next level of complexity.
The point of all this is: Isn’t such necessary over-simplification (or ‘spinning yarns’ as you called it) a forgivable, even necessary part of pedagogy? Perhaps the ability to reach higher food sources is a vast over-simplification –perhaps it’s even dead wrong. But it is easy to understand in a Darwinian sense (as it also was in the now discredited Lamarkian sense). It seems like such a “textbook case” –a label which itself invites the warning: “hypothetical and over-simplified scenario to follow for teaching purposes”. If the entire case for natural selection rested on giraffes alone, then the lack of abundant intermediates would be worrisome indeed. And apparently enough other cases also have enough paucity of actual record to motivate the punctuated equilibrium modifications to the theory. But requiring a biologist teacher to never use any over-simplified versions of a “just-so” story to teach a concept seems a bit like insisting that the physicist inflict air friction on his already challenged students who haven’t yet mastered Newton’s laws. Granted, these stories are making the challenge about whether N.S. should be considered a law (or a sufficient law) in the first place. A very worthy question. But *if* it passes muster generally, then I think I could forgive factual error of over-simplification in trying to elucidate the concept.
Merv,
You have made a big mistake in your discussion – the question of air friction, and Newtonian equations, has been examined in great detail by specialists, and the results rigorously examined and reproduced by independent workers – thus your teacher colleague should state that settled science needs to be taught at a lower level in a simpler fashion – not because such simplifications are necessary for the theory – the theory has been examined to a much greater level.
This cannot be said for natural selection – thus the error in your analogy. No-one has examined the giraffe matter completely and has shown it to be very complicated but nonetheless settled and repeatedly re-affirmed. The simplification is just that, the inadequacy inherent in that hypothesis. This approach unfortunately, is all too often used when examining the semantics of Darwinian thinking – it is just plain inadequate and cannot stand up to the scrutiny that say, Newtonian mechanics has recieved.
“They didn’t teach me much in high school biology, but I do at least know why giraffes have long necks…” Interestingly I had a comparable response to that when I mentioned this post to a guy at church yesterday (a trained pharmacist). I said “giraffe” and “evolution” and got the whole story back, word for mythical word.
There has to be something wrong if one can’t find a simple illustration of a theory that’s also true, especially if it’s being used to dismiss a former theory as untrue. I’m not sure science is the kind of subject best taught by fiction. Or at least, if it is, one should expect the same disillusion in later life as you get if you teach small kids that God lights the little candles in the sky each night.
The one example I remember from school was from physics, where I was taught the optics of the telescope by reference to forming actual images at the near-point rather than virtual images at infinity. It was marginally simpler, but actually hindered my understanding of the eye’s image forming capacity for many years. As, come to think of it, did the associated claim (repeated in biology, if I remember) that the eye forms the image by the crystalline lens, making the cornea, aqueous and vitreous out to be mere packing. The truth wasn’t much harder to comprehend, but gave a better idea of vision. In the end, enlightenment came by forgetting my education and working it out myself – no doubt scientifically virtuous, but educationally a failure.
And where does one draw the line? Are Haeckel’s misleading embryological drawings OK because, although they comprehensively misrepresent the complexities of development, they support a theory that, somewhere else perhaps, has good evidence going for it? Is it OK to show kids illustrations of non-existent transitional forms like Propterosaurus (the hypothetical precursor of pterosaurs) because science knows from the theory they must have existed?
Most importantly, though, the actual truth about giraffes, as I’ve tried to suggest in the column, casts serious doubt on the adequacy of the adaptationist theory the Just-So story is used to illustrate. If anything, the giraffe supports some other theory.
I wonder how skeptics would feel if religious education teachers used reports of miracles by (later discredited) Televangelists on the grounds that, though false, they illustrate the truth of less-accessible miracles like the resurrection. It would be a bit Jesuitical, wouldn’t it?
Gentlemen, I think you misinterpret the main thrust of my point. I am speaking only to common pedagogical practices (for better or worse). As to how well N.S. succeeds as a sufficient theory to explain change, I’m happy to be mostly a spectator watching all of you who are closer in with the life sciences make your points –which I listen to. So what I hear from Jon, and GD is that it most certainly is not, and has nevertheless enjoyed an unwarranted privileged position. Okay –so noted. And I also note that Lou disagrees, though he too has his own metaphysical bias for favoring what he does.
But on teaching matters, I must persist in my disagreement. Sometimes a tall tale or hyperbole does suffice and may even be a needed tool to help get a point across, and if students are disillusioned by this, then they have either not been prepared by their teachers for that mode of learning, or they have been indoctrinated into a modern western analytical mindset that disparages any learning that is not literal. But I will “spin a good yarn” when needed, without apology and with appropriate warnings to students as necessary that the truth to be learned is not always in the bare facts of this particularity. And in doing so, I believe I’m in pretty good company … thinking of where I can find a few parables.
Merv
Having slept on your post, I still disagree with it (at least regarding giraffes).
I’ve no problem with using fictional illustrations, for example, a hypothetical bug with variable colouring encountering selection against its background. One of the Church Fathers used as an illustration from nature of a theological point the phoenix, which of course is a fabulous beast. But it didn’t matter, because it was an analogy, not an exemplar.
Similarly, fables in non-scioentific settings are quickly distinguished by kids – I never thought the Elephant’s child reallygot his trunk by the great grey-green greasy Limpopo river, nor that ostriches could be relied on to hide their heads in the sand.
But a giraffe is a real beast, deserving the truth to be told about it, in a science lesson. I’m still using useful information my father taught me about the natural world before I went to school, and I believe that education should expand our first understandings, not provide illusions to be unlearned – especially when in most cases it’ll be the only biology teaching they get before they become grocers or accountants.
There are plenty of apparently incontestible adaptive stories one could use instead: the polar bear is genetically like the grizzly, and even more like the newly discovered Himalayan yeti, which is never reported as white. One could likewise use the arctic fox or stoat, whose winter colour change is clearly adaptive to snow. Or even the mountain hare, whose close cousin the irish hare has no white winter coat because there’s little snow.
The giraffe example, though, wrongly suggests (a) that a whole morphology depends on one selective pressure (b) that selective deductions are simple and hence (c) that adaptation is the universal nostrum for morphology – all it takes to see it is a Kipling-like imagination.
So I say, if you can’t find a real example of a phenomenon demonstrated to be true, one should use an illustration and teach that the truth is much more complicated. As indeed it is.
When discussing the philosophical implications of Darwin’s thinking, problems and evasions regarding function and teleology are numerous and the discussions sometimes take a bizarre twist. I have quoted Rosenberg in the past, mainly because he is a ‘dyed in the wool’ Darwinist and atheist, to ensure that I do not bring in an anti-Darwinian bias to these discussions. Rosenberg in his PoS discussions seeks to show a distinction between function, teleology and evolutionary ‘causes’ in biology. A point he has taken great pains to emphasise is that function, parts, and apparent purpose in large (complicated) systems, can be explained away by assuming that function is an analysis of simple parts, and as such has lost explanatory powers. He bases this on the belief that Darwin:
“…did was to show how a purely causal process – blind variation and environmental filtering (NS) – can produce adaptations, biological structures in the “causal role” sense of the term. In doing this he revealed that the appearance of design and purpose was a mere illusion – an overlay that we rolled out on a purely mechanistic world.”
I do not think that anyone can make sense of such statement unless they also share Rosenberg’s (ecstatic) view that:
“Darwin’s revolutionary accomplishments have a relevance to every aspect of intellectual debate in contemporary culture.”
We see in this example that instead of admitting the limitations of NS, in the face of numerous examples in which science has not only focussed on purpose and function, but an anti-Darwinian (or simply ignoring Darwin) approach has led to cures for debilitating diseases (Rosenberg, ironically, quotes the case of the first effective treatment for diabetes in 1912, to show how Banting and Best seemed to reject evolutionary commitment to evolution.) His arrogant judgement is that “when discovering the function of (these) cells, they were (merely) isolating the causal role….”
I continue to feel staggered at the enormity of hubris and blind trust in Darwin, displayed by atheists (and I suspect some theists TE chaps). It also shows how often advocates of Darwin will simplify their discussion to hide inadequacies, and they then overlay this with vast generalisations such as that quoted above, to essentially say, “if anyone doubts Darwin, well they are outside all science and culture.”
GD
Rosenberg’s arguments show the ultimate futility of materialist explanations for virtually everything: the evidence of ones eyes, in this case useful function, is never explained, but explained away – and yet, never sufficiently to prevent teleological “function” language being used universally in biology as the only rational alternative. In the same way reductional materialists explain away the mind, but cannot avoid using mental concepts and terminology to do so (“People are unwilling to believe their minds are an illusion, and too stupid to follow our reasoning”).
Of course, to some extent, despite the logical difficulties, such debunking of teleology could be true. It’s just that the alternative explanations are unuseable in practice, and completely convoluted, which is why they are only used in polemics, rather than in primary science.
Plausibility is the other issue, and since that is a human judgement one man’s “impossible” is obviously another’s “quite conceiveable.” But the giraffe story fits in here, because someone like Dawkins will (as our author reports at length) spin the simplicity of the adaptive story at a length that makes it sound exhaustive and scientifically incontestible. The cost is omitting all the actual detail that shows it to be mere fable. That is just dishonest science, and it’s written for adults, not school-kids.
One excuse is that molecukar biologists don’t study creatures in the field – but even schoolkids can go to the zoo and think.
Jon,
The arguments by atheists such as Rosenberg are deeper than my few comments may make them appear, and I am going through a number of his arguments carefully, in an attempt to get some insights into his thinking. At this early stage of my reading, I am inclined to ‘overlay’ Polanyi’s tacit knowledge concept – Rosenberg is so intent on ‘proving’ that other outlooks regarding science all end up appealing to a ‘God did it’, that I think he cannot help but end up in a muddle at times. So he is a determined atheist!
Yet my counter to my own impression is, “how else can an atheist think?”. It seems to me that Rosenberg’s greatest fear, and thus his overall purpose, is the intelligibility of the universe to human reason. I think if he can prove to himself that there is no substance to this, he would be happy with a human as an accidental entity with organic wiring firing neurons and illusions, and this as the basis for human understanding and knowledge – whatever I end up concluding, I like the intellectual effort Rosenberg has expended in his project.
Ah – the old problem: to prove by human reason that the universe is unintelligible to human reason, and then to write to persuade others by the same unreliable reason.
If you succeed in the circularity, you disprove God, but also man.
As I said before, I happily defer to others over the issue of any alleged sufficiency or insufficiency of N.S. But if to use something like the giraffe example is wrong, then it is wrong because the alleged truth it is supposed to teach isn’t really true; not because its particular case is a fiction. I do agree that there *should* be plenty of other non-fictitious accounts to illustrate the case as needed, and if the giraffe example is put forward as evidence rather than as illustration, then I will even concede it to be poor –no, dishonest pedagogy. But don’t write off all fiction, hyperbole, simplification, or parable as disingenuous. In doing so you lose one of the oft-used tools pulled from sacred writ. Those moderns who do are the ones who get in a muddle over whether events like Ezekiel’s valley of dry bones really happened instead of contemplating the real truth being taught. They have chosen the wrong gatekeeper for their truth discernment and are intellectually, perhaps even spiritually impoverished for the mistake.
Merv, as you see I was very happy to agree to fictional examples, or even fabulous beasts, as legitimate teaching points. Science couldn’t even be done without metaphor – what is maths but a metaphorical generalisation of messy reality?
Hooray for Schroedinger’s cat, which survived and is exhibited, stuffed, in Copenhagen Museum.
By the way, did I ever tell you about the time I was abducted by aliens?