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There could hardly be a more frequently stated requirement for natural selection than this: any beneficial genetic variation occurring in an organism, if it is to be evolutionarily relevant, must be stable, heritable, and long-lasting down through the generations. If a given variation is likely to pass away after a generation or two, or if it quickly suffers further change, then the normally long and slow process of selection will not have time to spread the variation (“fix it”) throughout a population. Patrick Bateson was giving voice to a universal consensus when he wrote, “For the Darwinian evolutionary mechanism to work, something must be inherited with fidelity” (Bateson 2017, p. 77).
But we might want to ask: If a certain amount of heritable stability is in general a requirement for evolutionary change, what is the counterbalancing principle that makes the change possible and is consistent with what we know of all organic processes of change? After all, every complex organism’s development presents us with continuous and often intense transformation — including the kind of radical “melt-down” of old structures and subsequent “re-creation from scratch” we saw in the metamorphosis of the goliath beetle (Figure 17.1).
This near-total melt-down of the old form, followed by the emergence of a dramatically different form leads us to a second, equally important question: Is it certain material products of an organism’s activity that must be stably maintained along a path of transformation? Or is it rather the contextual (holistic) capacity for activity — an activity through which not only do particular products arise, but also a coherent life is sustained and the character of a species (Chapter 20) is consistently expressed?
When the goliath beetle larva is overtaken by the seemingly chaotic “catastrophe” through which it will gloriously re-emerge in adult form, what is the organizing power, and what are the organizing ideas, through which this all-encompassing transformation of materials occurs? And how are the organizing ideas and power passed from one generation to the next?
(Is anyone writing Ph.D theses or journal articles or giving conference talks on such questions today? Would it even be allowed? Or has the materialist intellectual landscape of biology become a cowed and terrorized landscape — or simply an exhausted and dulled landscape?)
When we talk only about the inheritance of discrete products of activity, we have already shown a willingness to ignore the more fundamental problem of the origin of viable new traits, which require much more than some new bits of matter. Even if we are talking only about the development of the color patch (speculum) on a duck’s wing feathers (Figure 11.2), we still need to embrace in thought a huge range of molecular interactions that are possible only as an expression of an integrated and living whole.
The obstacle to a proper reckoning with change and inheritance lies in the focus on isolated products that are seen primarily in relation to a specific molecule (DNA) and its genes — genes whose mathematically calculable spread through a population is then thought of as equivalent to the spread of traits, which in turn is taken to be evolution. It is the demand for this sort of sterile calculability that leads to a one-sided emphasis on stable variation (gene mutations) rather than on the potent activity of self-transformation that organisms put on such obvious display.
Such, I think we will see, is the heart of the matter. But we may get a fuller grip on the issues by starting with the popularly effective case Richard Dawkins has made for an avowedly particulate, “gene’s-eye view” of evolution.
Richard Dawkins has been articulating his genocentric view of Darwinian evolution for over forty years, evoking, at the extremes, both passionate support and vitriolic criticism. Apart from the major controversies, however, there remains the oddity that the decisive failure of his view somehow rarely or never comes into clear focus, presumably because it is a defect found in virtually all conventional (and nearly all unconventional) thinking about evolution. I wish to pinpoint this failure as best I can.
In order for a genetic variation to be useful, Dawkins says over and over, it must be “potentially eternally heritable”. “I’m not wedded to DNA”, he assures us, but “I am wedded to this operational criterion that alterations in it go on forever potentially” (Dawkins 2009).
What he means is that, in order to be evolutionarily useful, variations must be selected for — perhaps not eternally, but at least for a long time. The ones that are harmful are selected against, and therefore tend to pass out of existence. But the truly beneficial adaptations can be selected and selected again, generation after generation, without any in-principle limitation. They are in this sense “potentially eternally heritable”, which can only be the case if they are extremely stable.
The transgenerational longevity (stability) of genes is why Dawkins favors them, rather than whole organisms, as the true reproducers, or replicators, upon which natural selection works. “Bodies don’t get passed down the generations; genes do” (Dawkins 2006b, p. 79). Just about all the details of one’s body can change from one generation to the next. Bodies are, compared to genes, “like clouds in the sky or dust- storms in the desert. They are temporary aggregations or federations. They are not stable through evolutionary time” (Dawkins 2006a, p. 34).
For Dawkins, then, it is a non-repeatable collection of material bits, and not the character or the principles of organization at work in the body, that constitutes its identity. It is difficult to see how this amounts to much of an identity at all. But, in any case, such a mere aggregation can hardly be a significant evolutionary cause. “An individual organism is not [an evolutionarily relevant] replicator, because alterations in it are not passed on to subsequent generations” (Dawkins 1982). While an organism as a whole may be “the all important instrument of replicator preservation: it is not that which is preserved”.1
No one, incidentally — neither Dawkins nor any other biologist — is saying that the organism’s phenotype is irrelevant to evolution. Their claim is that the real relevance has to do with the fact that certain genes have contributed to this phenotype and therefore to the survival capabilities of the organism and its offspring. This in turn influences which genes will be passed down the line and survive in the larger population. It is, in this picture, the change (mainly the beneficial variation) in genes that most directly explains and maps to adaptive evolutionary change.
But beyond this question of the organism’s survival, in which they themselves have a say, genes are thought to “live” independently of the particulars of an organism’s life. They follow their own stable arc down through the generations, remaining just what they are except for the occasional chance mutation. They constitute, according to Dawkins, a nearly eternal “river of information”. This river “passes through bodies and affects them, but it is not affected by them on its way through” (Dawkins 1995, p. 4).
Implied in all this — and very important for Dawkins — is the idea that genes can be conceived in something like a particulate fashion. “I insist on an atomistic view of [genes]”, he wrote in The Extended Phenotype ("Dawkins 2008, p. 113). And elsewhere he has elaborated: “What I have done is to define a gene as a unit which, to a high degree, approaches the ideal of indivisible particulateness. A gene is not indivisible, but it is seldom divided. It is either definitely present or definitely absent in the body of any given individual. A gene travels intact from grandparent to grandchild, passing straight through the intermediate generation without being merged with other genes”.2
Dawkins is well aware that much of the criticism he has received comes from those studying the development of organisms. These observers find it very hard to recognize his genes in the developmental processes they investigate. It is, in many developmental contexts, impossible to assign genes long-lasting, discrete, well-identified causal roles, and also impossible to view genes as passing through these contexts unchanged in their functional significance for the developing and evolving organism.
In offering repeated responses to such criticism, Dawkins has made it clear that he considers the intricate choreography of development — in which many non-genetic factors figure prominently — to be irrelevant for evolution. But he emphatically rejects the charge that the gene-centered view denies “proper respect to the Great Nexus of complex causal factors interacting in development” (Dawkins 2008, p. 99). “I yield to no one”, he told an Oxford debate audience, “in my admiration of the complexity of feedback loops, of the details — the immensely complicated details — whereby genes actually do influence phenotypes. There’s absolutely no suggestion that it’s irrevocably deterministic, there’s absolutely no suggestion that it’s simple” (Dawkins 2009).
And yet he fears that too many people get carried away by the intricacies of development. It is true, he grants, that it is precisely through development that we see how an organism grows and adapts toward maturity through complex and holistic processes. But these all too easily distract us from the decisive role of genes in evolution — a mistake he derisively equates to the lament, “Dear oh dear, development is a terribly complicated nexus, isn’t it?” (Dawkins 2004).
He himself prefers “frankly facing up to the fundamental genetic nature” of Darwinian selection (Dawkins 2008, p. 28). Development may be a “complicated nexus”, but evolution is merely a matter of pristine bits or bytes in an informational DNA sequence.
The fact just is, he says, that we learn nothing of interest by looking at the dynamic interrelations — the forming and dissolving, spaghetti-like causal arrows — through which DNA is fitted to its proper place among all the cellular activities. “There may be backwards arrows in all sorts of other senses but, in the sense that specifically matters for Darwinian evolution, the causal arrow of biological development from genotype to phenotype really is a one-way arrow” (Dawkins 2004).
The key to all this lies in two features of genes, as Dawkins sees them: (1) They can, through the occasional gene mutation, produce evolutionarily relevant variation in organisms. And (2) this genetic variation is characteristically stable; through the replication of DNA it can be passed down the generations potentially forever. This means that natural selection can, over as much time as necessary, change the distribution of genes in an evolving population. Very little other than genetic change, so the argument goes, yields particulate variation with such stability and lasting power and therefore little beside genetic change can contribute to evolution.
So, however vague and non-determinate genes may be for development, they are decisive for evolution. That’s why, for the evolutionist, “the complexity of development itself is an obscurantist red herring” (Dawkins 2004). Yes,
development is terribly complicated, and we don’t yet understand much about how phenotypes are generated. But that they are generated, and that genes contribute significantly to their variation are incontrovertible facts, and those facts are all we need in order to make neo-Darwinism coherent (Dawkins 2008, p. 22).
It doesn’t matter how complicated the developmental support structure, nor how utterly dependent DNA may be upon it, the central question remains: which elements ... of development have the property that variations in them are replicated, with the type of fidelity that potentially carries them through an indefinitely large number of evolutionary generations? (Dawkins 2004).
So it’s not just that genes qualify as drivers of evolution, but also that the other players in development do not. When we shift our attention from development to evolution, “the special status of genetic factors rather than non-genetic factors is deserved for one reason only: genetic factors replicate themselves, blemishes and all, but non-genetic factors do not” (Dawkins 2008, pp. 98-99). And, in perhaps his most succinct summary:
The quality of hi-fi variation … is a precious, rare, onerous, difficult talent, possessed by genes and computer viruses and a few other things — but genuinely few … In order for anything to evolve by natural selection, there has to be variation in something that is both potentially long lasting and causally powerful, so that there emerges a difference, on the evolutionary time-scale, between the state of the world if one variant survives compared with the state of the world if an alternative variant survives. If neither variant survives more than a couple of generations anyway, we are not talking evolution at all (Dawkins 2004).
Genes, according to Dawkins, survive this rare and onerous test.
Dawkins is admirably forthright about his desire for a purely genocentric explanation of evolution, and therefore also about his need to put evolution and development into different boxes. But it doesn’t work. One thing both he and his critics could probably agree on is that development shows genes actually carrying out their biological roles. If we want to know what genes are and what they mean for the organism, then all the abstract talk in the world about “pristine bits and bytes” and “rivers of information” cannot supplant what we actually observe about genes in living contexts.
And this is where the problems begin. If Dawkins really is willing to concede the reality of the “Great Nexus of complex causal factors interacting in development” — if, that is, he recognizes the holism implied by the fact that the “causal arrows” of development run in all directions as guided by the larger context — then how can he turn around and say: “in the sense that specifically matters for Darwinian evolution, the causal arrow of biological development from genotype to phenotype really is a one-way arrow”?
Development, we can be sure, just is whatever it is, and it doesn’t become different, right down into the nature of its causation, depending on whether we happen to be thinking about evolution at the moment. I can’t believe he would argue with this, and I assume he would say his point is more subtle. But how that point might actually be put in a defensible way never clearly emerges. If genes accomplish their effects only in the context of tortuous interactions with innumerable constituents of the cell, then how do we avoid the conclusion that an evolution of these effects must require an evolution of the entire pattern of interactions?
I know: he would presumably say that cells, like bodies, are mere “clouds” or “dust storms”, and couldn’t possibly evolve. This is the strangest of arguments, but read on.
It does seem plain enough that Dawkins is saying something like the following, however he would like us to interpret it: while genes may not single-handedly shape the mature horse from a zygote, they do more or less single-handedly account for the transformation of the fox-sized horse ancestor, Hyracotherium, into the horse we know today (Chapter 19).
But consider: if the evolutionary re-shaping of animals such as Hyracotherium into the modern horse involves, as it must, a reorganization of the detailed, unthinkably intricate totality of developmental processes; and if genes are the lone, or almost the lone, factors accounting for this evolutionary reorganization, then I don’t know how to avoid the conclusion that genes are the causal, controlling masters of development generally. And this suggests that Dawkins doesn’t really accept the fact that multi-directional causal arrows are at work in the “Great Nexus of complex causal factors interacting in development”. And if he doesn’t accept this, it is presumably because he realizes that taking development at face value would torpedo his gene’s-eye view of evolution.
My suspicion is that he simply never closely engages with the problems of development because he is uninterested in them and they are alien to his entire point of view.
In any case, the underlying problem is that the genes involved in complex developmental processes are not the genes Dawkins theorizes about. Think, for example, of the two key planks of Dawkins’ argument and notice the distortion he introduces in each.
(1) Genes (Dawkins says) can, through the occasional mutation, produce evolutionarily relevant variation in organisms. The truth is, rather, that genes do not produce anything on their own. We have almost heard Dawkins himself say as much in the preceding paragraphs, where he mentions the unfathomed complexity of developmental processes and the “spaghetti-like” and “backward” causal arrows featured in them.3
Differences in cell traits always arise from the deeply interwoven activity of whole cells. In particular, the cell-to-cell variation along the path of a differentiating cellular lineage is a matter of the changing character of the entire cell as it participates in a transformative process leading to an endothelial cell in the inner lining of a blood vessel, or an amoeba-like macrophage devouring pathogens, or a crystalline, transparent cell of the eye’s lens.
Yes, Dawkins claims to accept the “complicated nexus” of development. But where does he admit to, or even notice, the consistent, reliable, well-directed, holistic character of this development? A cell taking its place, along with its forebears and descendants, upon a coherent path of whole-cell change leading finally to a fully developed lens cell that must last a lifetime hardly shows the transience of a “dust storm in the desert”.
Dawkins, of course, applies that phrase to entities involved in evolution, not development. But this is exactly the problem. The effort to separate evolution from development, as we will see shortly, does horrible violence to the most basic realities of inheritance upon which evolution depends.
Meanwhile, it is well to recognize the mystery we are up against in development. The differentiating cell acts as though it somehow “knows” where it is along the larger path of transformation. It “knows” how to use its inheritance from its parent cell not only to venture upon its own variation from that parent, but also to provide a distinctive inheritance for use by its daughter cell as material for still further variation — all this as a way each cell can participate in a coordinated movement toward an ultimate “goal” it can neither “see” nor consciously plan for. The cell participates, that is, in the intention or directiveness of its larger context, just as its constituent molecules participate in its own directiveness.
(2) Genetic variation is “potentially immortal” (Dawkins 2008, p. 83) — stably holding to its own identity and remaining unchanged by the organisms hosting it down through the generations.4 This is another radical distortion of the truth. A whole cell may indeed be potentially immortal in Dawkins’ sense, something well-known by biologists who have, in laboratory dishes, cultured single “cell lines” derived from a single cell — and have kept these cell lines going for several decades with no apparent limitation in sight. Actually, all life on earth is commonly thought to be the flourishing, down through countless generations and in countless different species, of the life of a single original cell of unknown origin.
But if cells are potentially immortal in some sense, genes — in the causal sense that Dawkins fixates upon — certainly are not. In fact, their causal powers do not even remain constant in a single cell over its lifetime. This is because local activity within the cell is always being coordinated and repurposed according to the needs and interests of the whole cell and organism.
Dawkins gets his river of fixed, unchanging, selectable “particles” of inheritance only through an act of intellectual violence — only by mentally wrenching certain molecular parts of DNA (for example, the nucleotide bases constituting the genetic “code”) from their meaningful, dynamic chromosomal and cellular contexts. He abstracts them from the stream of life in which alone they become what they are moment by moment. He wants dead, material things for theoretical manipulation. You might say that he abstracts the genetic “letters” from the cellular “sentences” in which they find their life and meaning.
Only such an act of abstraction can give him what he needs: heritable particles to which he can apply the same name (even if not the same meaning) from one context to the next — particles that can be tracked within both individual organisms and breeding populations. Then, because the name of any particular gene remains the same, he can pretend he is always talking about precisely the same, unchanging thing.
And yet we know very well that, in the living and meaningful sense, genes never remain unaltered for long. The “same” genes can have radically different causal implications in different contexts within a single cell or organism, and also in different kinds of cell or organism. Even when we think a gene has analogous functions in different organisms, it can turn out that the functions have unrecognizably different physiological realizations. This reflects the very different ways of being from one kind of organism to another — ways of being in which genes are caught up rather than being the decisive orchestrating factors.
As one of endless evolutionary examples: the PAX6 gene is found in both fruit flies and mammals, and has been thought of as a “master control gene” for the formation of eyes. But not only is its activity now known to be interwoven and interdependent with that of countless other genes and their regulating factors and functions, but the compound eyes of a fruit fly are altogether different organs compared to the eyes of a mammal. If we try to imagine a gene, as a single, supposedly well-defined causal unit, independent from the stream of life in which it finds itself and yet at the same time fitting itself into the completely different physiological contexts of fly and mammal, the picturing does not go well.
Throughout the first half of this book we have seen over and over how DNA is caught up in, and given its functional identity by, its context. And in Chapter 21, I illustrated some of the countless ways in which the DNA content of genes is itself twisted, untwisted, bent, distorted in various ways, chemically modified, moved around in the nucleus, converted to nonstandard double-helical forms or even non-double-helical forms, and otherwise driven by the cell into conditions that transform its genetic role and identity.
And so, we have now seen that it is the principle of holism that subverts both premises of Dawkins’ argument. (1) Genes may be among the conditions for cellular (and organismal) variation, but they do not produce that variation; the whole cell (or organism) does. (2) Genes, considered as important causal factors in evolution, are not “potentially immortal” — or even potentially “lifetime-lasting” within individual organisms — because the whole organism defines and redefines their nature and identity as it goes through its life-long processes of development.
To put the matter in these terms, however, would doubtless provoke Dawkins’ skepticism. For he has very publicly worried that “a kind of ‘holistier than thou’ self-righteousness has become fashionable”, and further, “There are times when holistic preaching becomes an easy substitute for thought, and I believe the dispute about units of selection [genes, in his view] provides examples of this” (Dawkins 2008).
But when it comes to understanding the life of organisms, holism is just about the most disastrous thing to lose sight of.
I have just now been contending that if there are lower-level, “potentially immortal”, directive, and agential entities within organisms, then they are whole cells, not genes.5 But what I have said about cells applies all the more to organisms (which Dawkins identifies with “bodies”).
Recall Dawkins’ claim that bodies are like clouds or dust storms in the desert because they do not exhibit the constancy required for natural selection and evolution. But this fantasy of the whole organism’s transitory existence — its lack of a stable and enduring identity — is as wildly off the mark as his invention of the “almost eternally” durable genetic particle.
It is true that, much like a differentiating cellular lineage, a multicellular organism as a whole undergoes continual change. It is alive. In its development, it grows from a zygote to a mature form. This is a drama of progressive self-manifestation or self-realization, a drama of reliable, continuous transformation, where no material structures (including chromosomal structures) remain always the same. It’s what organic activity always is: if an organism, along with all its parts, is not changing in a well-directed and holistic manner, it is dead.
But well-directed development no more represents change without stable identity than does cell differentiation. If a differentiating cell “knows” very well who it is and where it is going, all the more a developing organism follows a reliably defined path of development and self-expression leading to its own fullest realization. Crucially, this path is never precisely defined or materially determined. For example, adjustments to unpredictable environmental disturbances during development may continually occur. But the adjustments are in the service of the organism’s fullest expression of its true nature.
The identity here is that of a dynamic unity. But a dynamic unity capable of maintaining itself while actively participating in and vulnerable to its context is a far more profound center of identity and power than a supposedly static particle impervious to its surroundings.
Never, except in the imagination of someone preferring to live within a world of inert (but nicely stable) particles, could the organism have been likened to a cloud or dust storm. Its unity and stability lies in its giving material expression to a specific kind or species (Chapter 20). Every complex organism is an almost miraculous, stable, reigning unity governing many differentiating cell lineages (over 250 in the human case). The reliability and constancy of this sort of identity is so evident that for millennia nearly everyone erroneously assumed that all species were eternally fixed in their essential nature.6
In order to correct this view today, we do not need to throw out the constancy everyone can observe, but only to render the idea of that constancy more dynamic in line with modern evolutionary insights. An organism’s identity is crucially reflected in its ability to adapt to a changing environment in line with its own species-character and potentials. We see this dynamic identity and adaptability even in individual organisms, and also in our own biographies. Our immediate experience gives no support to the idea that growth, development, and change imply a lack of coherent identity.
To observe life, then, is always to watch an interplay of change within continuity, plasticity within constancy. Both aspects of the living interplay run through all biology. Perhaps our most convenient access to them comes through the study of development, as when we watch a whole organism “coming to itself”, or watch a differentiating cellular lineage.
Here the principle of change is easy enough to verify — and it no more relies on the absolute constancy of the material products of change than does the metamorphosis of the goliath beetle larva into a mature beetle (Box 17.1). I described in Chapter 17 how hundreds of cell lineages in our bodies “evolve” (are differentiated), not by remaining mostly unchanged, but rather by compounding change upon change down through the cellular generations. The result is a profound, qualitative transformation of whole cells, explainable only as a power of activity, not as a determination by previous material constituents.
It is difficult to doubt that this compounding of change upon change is owing to an orchestrating power that works throughout the entire cell — a power not at all one-sidedly determined by genes, their mutations, or any other material constituent of the cell. We are watching a cell radically re-organize itself in its entirety.
But think what this means. If many developmental changes in a cell lineage are not stable and heritable over any large number of cellular generations, it is because they had better not be. After all, the lineage is on the way to somewhere, proceeding directionally along a pathway of integral, holistic transformation. This suggests how differently we will have to look at evolutionary processes once we are willing to acknowledge the nature of organic change and a directive agency.
There is no need to avert our eyes from the “dangerous fluidity” of the whole situation. For the other aspect of the process of cell differentiation lies in the fact that the differentiating cellular lineage is remarkably sure of its identity: it is this lineage, and is powerfully “insistent”, in tune with its context, about reaching its own mature character. And, having reached its maturity, it is capable of stably maintaining it as long as necessary, while never losing a degree of adaptability.7
So here in the organism’s development and cellular differentiation, we see compelling identities involving, not the stasis of inert particles, but rather a marriage of constancy and change, selfhood and transformation — a reality it would be very strange for any student of evolution to lose sight of.8 What is constant is not a mere physical product, but an active way of being. As I have put it a number of times (drawing on a phrasing of the Greek scholar, Joe Sachs), an organism is “continually at work remaining itself”. We could say much the same of a cell. Physical entities — aggregations of particles, if we insist against all reason in thinking that way — are the inconstant residue of such activity, not a cause of it.
The central problem that Dawkins avoids reckoning with is this: everything we have noticed about the enduring unity, purposiveness, and transformational powers of the cell and organism applies, not merely to development, but also directly to evolution. That’s because
what passes hereditarily between generations is never less than a whole cell, and this whole cell is never less than a whole organism. And, as we have seen, both the cell and the organism exhibit an enduring, purposive identity possessing not only constancy, but also a profound transformative capacity — exactly the combination an evolutionary theorist must look for.
Anyone who wants to claim that genes, rather than whole living cells (organisms) are the basis for evolution needs to explain why we must ignore everything we know about cells — about how they proceed so effectively along evolutionary (developmental) trajectories and how they intricately, flexibly, and authoritatively enlist their genes along with all their other resources in achieving their ends.
Further, why should we assume that the totipotent zygote (capable of engendering all the cell lineages of the adult organism) brings nothing of its self-transformative, re-organizing powers across the generational gap — nothing, that is, of evolutionary relevance? There is, of course, really no gap at all, but only continuous life. And the activity of whole-cell transformation is fully as insistent on the parental side — in the unique differentiation of germ cells and the seemingly against-all-odds merging of distinct germ cells with distinct genomes in a single zygote — as it is on the offspring side.
We know a great deal about the powers of reliable change possessed by cells and organisms, and we also know about a gene’s complete inability to represent on its own an organism’s expressive traits. If it happens (as it does) that an organism’s abilities as a living, developing, striving-to-survive “vehicle” for its genetic cargo require all its vast array of transformational powers, and if we see it employing those powers with almost infinite intricacy and adaptational effectiveness in all its cell lineages, why should we imagine these powers going dead or inert at those especially intense moments when one generation is actively preparing for a successor generation.
One can only assume that Dawkins has proven blind to the only agents of biological transformation we know because, as a materialist and reductionist, he simply cannot tolerate the idea of biological agency, despite what he witnesses in every organism he has ever seen. He must overlook active and purposive organic wholes by conceiving organisms as built, bottom-up, from collections of inert particles and mindless processes. But, as I have pointed out repeatedly in this book, such a conception is never possible to hold consistently, and all observation-based biological description immediately controverts it. (See, for example, Chapter 2.)
The organism’s dynamic, transformative capacities are so clearly underwritten by everyday perception that they need not even be mentioned in order to be casually, if also silently, relied on by the evolutionist. But when the failure to mention them turns into an active “conspiracy of silence”, so that our theories of evolution must ignore the obvious, then something has gone badly wrong.
Sterile Particles, or Living Cells?
It would hardly be surprising to suggest that a great deal of one’s evolutionary theorizing depends on whether one approaches the topic with the mindset of a materialist and reductionist or, to the contrary, ascribes to every cell and every organism a wise agency and purposiveness expressed in all its living activity. But before tackling that issue directly, one can always begin by looking at what we know of cells.
This chapter is grounded in a seemingly incontrovertible fact observed in all complex organisms: their cells proceed through dramatic processes of differentiation reflecting organizing ideas in which the entire cell is caught up and through which it undergoes profound transformation. Cells can, to all appearances, become as different from each other as any two organisms with dramatically different genomes. But the differences between cell lineages in a single organism cannot, in any fundamental sense, be attributed to genetic differences, because all the lineages derive from a single, inherited genome.
The question this poses for evolution is straightforward — and puzzlingly ignored on all sides: Why should this transformational capacity of whole cells be ignored as a source of evolutionary change — ignored, that is, when we shift our view toward the cell-organism that in undisputed fact bears the full inheritance passing between generations? It’s true that the question is a difficult one because the kind of dramatic, qualitative, whole-cell transformation we encounter so often in developmental studies cannot be reduced to mathematically analyzable changes in gene sequences and gene frequencies. But why wouldn’t we expect any explanation for the evolutionary transformation of an organism to be at least as complex as the organisms themselves? This complexity of holistic processes is certainly no reason to turn away from their investigation when we are seeking to understand evolution.
2. Dawkins 2006a, pp. 33-4. Along these same lines, Dawkins has written that the “digitalness [of genes] is probably a necessary precondition for Darwinism itself to work” (Dawkins 2006b, p. 163). I discuss this remark along with the non-digital character of genes in Chapter 21, “Inheritance, Genetics, and the Particulate View of Life”.
I would add here that my criticism of Dawkins’ “atomistic” genetic particles is in no way intended to deny the fact that genes, like much else in the organism, possess their own particularity. Just as an enzyme has an affinity for a particular substrate or substrates, so also a gene is associated with its own suite of protein variants. The cell flexibly employs the gene as a resource for the generation of one or another of those variants. The cell, of course, requires many other resources for this task, and the decisive, repeated modification of a protein over its lifetime is achieved after the gene-resource has been brought into play for the initial synthesis of the protein.
3. It is similarly false when Dawkins says that genes “replicate themselves”. They are utterly helpless to replicate themselves — and also to perform error correction on themselves. It is the cell that both replicates them and carries out DNA damage repair. (He surely does understand this, despite his language.) On the power of proteins to manage DNA and reassemble shattered DNA, see Chapter 8.
4. More specifically, it is genetic variation in the germline that Dawkins says is potentially immortal.
5. It is important to realize that DNA with its genes must also have a share in the cell’s character inasmuch as it can participate in, or be caught up in, the well-directed purposiveness of the cell. But DNA is not itself the responsible center or mediating agent for that purposiveness, which belongs to the larger context. We are, as always when dealing with organisms, looking at an organic relationship between part and whole, and between wholes nested within larger wholes.
6. It is this kind that, as we saw in Chapter 20, the usual genetic studies cannot approach. For these studies unavoidably focus on trait differences between closely related organisms, and the differences found are then correlated with gene differences. So one is studying no more than inessential changes among organisms of the same general type and is gaining little or no insight into the determinants of different types. (We should note that Dawkins’ genetic preoccupations are based precisely on the results of such studies, with their limited applicability to evolution.) The limitations of genetic studies are rooted in the fact that genetic crosses between organisms of substantially different types are as a rule non-viable.
7. It would be good not to forget what we learned in Chapter 6 about cells changing their “identity” in the hair follicle niche, depending on circumstances. We have to understand the cell’s identity in a broad enough way to recognize this possibility of metamorphosis. It illustrates how cells are subordinate to, and receive their identity from, the larger context and the organism as a whole.
8. Change and continuity: every organic whole embodies — lives by means of — a harmonization of these contrasting principles. But these are exactly the principles that any theory of evolution must somehow hold together. It’s obvious enough that you can’t have evolution without change. But so, too, without continuity there is only the arbitrary substitution of some elements of a mere aggregate for others, with nothing that lends significance to the result. If the change is to be non-arbitrary or coherent, there must be a persistent character attributable to the whole. Without an underlying continuity no enduring, nameable entity or being exists of which we can meaningfully say, “Yes, this is evolving”. There is instead just “one damn thing after another”.
And we should add this: if, as in the organism, all the material elements are subject to change, then the underlying continuity must be immaterial (Barfield 1965, p. 96). But then, that is how we have understood the organism all throughout this book — as a bodily exterior “shone through” by an interior.
Barfield, Owen (1965). Unancestral Voice. Middletown CT: Wesleyan University Press.
Bateson, Patrick (2017). Behaviour, Development and Evolution. Cambridge UK: Open Book Publishers.
Dawkins, Richard (1982). “Replicators and Vehicles” in Current Problems in Sociobiology, edited by King’s College Sociobiology Group, pp. 45-64. Cambridge: Cambridge University Press.
Dawkins, Richard (1995). River Out of Eden: A Darwinian View of Life. New York: BasicBooks.
Dawkins, Richard (2003). “An Early Flowering of Genetics”, The Guardian (February 8). https://www.theguardian.com/books/2003/feb/08/peopleinscience.evolution
Dawkins, Richard (2004). “Extended Phenotype — But Not Too Extended. A Reply to Laland, Turner and Jablonka”, Biology and Philosophy vol. 19, pp. 377-96.
Dawkins, Richard (2006a). The Selfish Gene. Oxford: Oxford University Press. Originally published in 1976.
Dawkins, Richard (2006b). The Blind Watchmaker, third edition. New York: W. W. Norton. First edition published in 1986.
Dawkins, Richard (2008). The Extended Phenotype, revised edition (1999), reprinted with corrections (2008). Oxford: Oxford University Press. Original edition published in 1982.
Dawkins, Richard (2009). Comments during “Homage to Darwin” debate, Balliol College, Oxford University (May 8), featuring Richard Dawkins, Lynn Margulis, Steve Bell, and Martin Brasier. The event was chaired by Oxford’s Denis Noble. Links to recordings of all three parts of the event can be found at http://www.voicesfromoxfordorg/?s=homage+to+darwin . (Downloaded December 5, 2022.)
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Steve Talbott :: A Curiously Absolute Demand for Stable Variation