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Evolution As It Was Meant To Be
A book in progress by
Stephen L. Talbott

Chapter 21

Inheritance (1): The Whole Organism

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This is a preliminary draft of one chapter of a book-in-progress tentatively entitled, “Evolution As It Was Meant To Be — And the Living Narratives That Tell Its Story”. This material is part of the Biology Worthy of Life Project. Copyright 2017-2021 The Nature Institute. All rights reserved. Original publication: October 28, 2021. Last revision: October 28, 2021.

Tags: evolution/and development; evolution/inheritance; evolution/and mutations; gene/as difference-maker; holism

In 1923 Wilhelm Johannsen, the Danish plant physiologist and pioneering geneticist who had earlier given biologists the word “gene”, expressed concern about the way genes were being conceived as neat, cleanly separable causal units. He made the following curious remark, which remains today as intriguing as ever, despite its never having prompted much serious discussion within the field of genetics as a whole:

Personally I believe in a great central ‘something’ as yet not divisible into separate factors. The pomace-flies in Morgan’s splendid experiments continue to be pomace flies even if they lose all “good” genes necessary for a normal fly-life, or if they be possessed with all the “bad” genes, detrimental to the welfare of this little friend of the geneticists. (Johannsen 1923, p. 137)

The pomace-fly, of course, was the fruit fly (Drosophila melanogaster) that Thomas Hunt Morgan, in his Princeton University laboratory, was famously converting into a “model organism” for genetic studies. Thanks to procedures for mutating genes, controlling the mating of the flies, and tracing the inheritance of traits, this was the fateful period during which “genetic” was becoming synonymous with “heritable”. The fact that whole cells — and not merely genes — pass between generations was progressively losing its significance in the minds of biologists interested in inheritance and evolution.

Johannsen saw that this new genetic work was based on the assumed existence of separate and independent causes of traits, and therefore left untouched what might easily be seen as the central problem of inheritance: the faithful reproduction of kind, or type — that is, the maintenance of the integral unity that harmonizes all the particular traits and parts of an organism and gives that organism its characteristic way of being. While mutated genes might result in (typically pathological) differences in certain narrowly conceived traits, this sort of change never reached through to the fundamental identity of the organism. Whatever the introduced variations (mutations), the pomace-flies always remained pomace-flies.

Johannsen’s problem arises because we can hardly help recognizing the distinctive unity of a living being — a unity we have great difficulty equating to any particular collection of individual parts. Rather, the organism seems in some way responsible for its parts. We never see an organism being constructed or assembled from already-existing parts. In its development it works to bring them about and differentiate them. Every organism is the power to do this work, and the power is not derivable from its results. If some of its parts become deformed, the organism works out of its unity to compensate for the deformities, doing so according to the way of being of its own kind.

But what sort of genetically investigated differences was Johannsen dismissing as disconnected from the problem of the whole? In his brilliant, and still decisively relevant1 1930 book, The Interpretation of Development and Heredity, the British marine biologist E. S. Russell took up Johannsen’s concern. “When we say that a child shows a hereditary likeness to its father”, Russell wrote, “we mean that it resembles its father more closely than it does the average of the population. The likeness is observable in respect of those individual characteristics that distinguish the father from the rest of the race” (emphasis added). Much the same can be said of the child’s resemblance to its mother.

It’s also possible that there will be no particular resemblance to either parent. “But yet in all three cases the child would show the characteristics of its species and its race — it would be a human child, distinguishable as belonging to the same racial type as its parents”. As Russell then noted, this general resemblance in type, whereby all members of a species share an entire manner of development and way of being, can hardly be compared to the inheritance of this or that inessential variation wherein a parent happens to differ from most other members of the species.

This distinction between a fundamental, shared nature, on one hand, and individual peculiarities that occur within that shared nature, on the other, has practical implications for genetic research:

The broad general resemblances of type give no hold for experimental or statistical treatment, and have accordingly on the whole been ignored. But it is this general hereditary resemblance which constitutes the main problem. [The gene theory] deals only with differences between closely allied forms, and with the modes of inheritance of these differences; it leaves the main problem quite untouched as to why, for example, from a pair of Drosophila only Drosophila arise. It takes for granted the inheritance of Johannsen’s “great central something” — the general hereditary equipment of the species. (Russell 1930, pp. 269-70)

Whole versus part

The issue here concerns the distinction between, first, individual features of an organism imagined as discrete and more or less separable parts (traits or “characters”) somehow caused by particular genes; and, second, the integral unity whereby every organism exists and functions as a single whole. Isolated “characters” — for example, the color of a pea or of an animal’s eyes — are much more easily assessed and compared in two similar organisms than are the characters of two whole organisms of different types. The usual genetic breeding experiments that compare differences in isolated traits of closely related organisms can hardly be applied to the different natures and ways of being of an antelope and a bison — let alone an eagle and a pig — if only because the fact of infertility between fundamentally different types normally renders routine experimental inter-breeding impossible in such cases.2

You might think that, given the broad fact of infertility between different types, biologists would have cast around for new approaches to the problem of an organism’s inherent governing nature, even if it required quite different methods from those they were trained in. What is at stake, after all, is our understanding, not only of the organism, but also of evolution. We certainly cannot answer all the questions we have about fundamental evolutionary change — for example, questions relating to the origin of basic body plans — merely by looking at how specific gene variants correlate with differences between closely allied forms of the same general type.

The picture I have been developing in this book shows us that organisms are in fact coherent, qualitative, story-telling wholes that inform and define their own parts. The parts, being so informed, share in each other’s identity and become inseparable features of a larger unity. Some such picture has been acknowledged by many biologists throughout the history of their discipline. If the picture is accurate, then the power to maintain this larger unity across generations — which also suggests a power to transform the unity — would seem to be central to our understanding of heredity and evolutionary change.

The issue here is truly decisive. Have biologists in our day lost sight of the whole organism because of their fixation upon the molecular parts known as genes? And have they lost sight of evolutionary dynamics because of their fixation upon the hereditary transmission of genes rather than entire living cells?

Russell laid direct hold of this matter when he considered what it meant to realize that the activity of an organism cannot be reduced to the actions of its individual parts. If it is truly the case that the organism as a whole plays a governing role whereby it continually informs its parts with its own character and “catches them up” within its own powers of activity, then the performance of the whole “can be [hereditarily] transmitted only by a whole, i.e. by the egg in its entirety, which at the very beginning of development is the new individual” (Russell 1930, p. 283).

Russell then cited a 1903 comment by the German botanist F. Noll (who was writing before the word “gene” came into usage):

If the egg-cell of a lime tree is already a young lime tree, there is no need of any idioplasm, germ-plasm, pangens, or heredity-substance to render possible its development into a lime tree; the egg-cell as a whole is the heredity-substance. (Russell 1930, pp. 287-8)

Change and continuity

In Chapter 18 (“Evolution Writ Small”) we were given one view of the whole organism. There we saw the many dramas of cell differentiation in humans. Hundreds of cell types, sometimes outwardly differing from each other as much as an eel differs from a goldfinch, are woven with almost infinite attention, intricacy, and complexity into the integral, ever-adapting unity of the organism as a whole.

Amid this diversifying whirl of cell lineages in a human embryo, where genes are simultaneously being summoned into the service of wildly different cellular phenotypes, we can hardly help asking: What is the unifying and coordinating source, or power, through which all the differentiating cells are formed into coherent tissues, organs, organ systems, and the stable, functional unity of an entire human being?

To get a grip on the organizational challenge, think first of the “humble” yet extremely dynamic, complex, and context-sensitive “hair follicle niche” we looked at in Chapter 6 (“Context: Dare We Call It Holism?”). Then consider the unthinkable number of distinct niches, many of them microscopically small, in the liver, or in the kidney, or in the brain, pancreas, bone marrow, and every other part of the body. They are all dynamic, complex, and context-sensitive, and vast numbers of such interpenetrating contexts, while mutually shaping each other, must somehow come under a global coordinating power reflecting the form and life of one human being.

The interactions within and between all these niches, organs, and organ systems look as though they are virtually infinite. Furthermore, environmental conditions and bodily activity are continually changing in an endlessly varying manner. As a result, those “virtually infinite” interactions, including the patterns of gene usage in billions of cells, is only momentary. It must be capable of being reorganized minute by minute and hour by hour.

Further, the task of global coordination goes far beyond what we normally think of as coordination. For the parts being coordinated are always in the process of becoming more or less different parts. We are never speaking merely about the coordination of existing parts, but also about their transformation — and, ultimately, their coming into, or passing out of, existence.

Is all this not one angle from which to view Johannsen’s “great central something”? Yet, a century after his comment biologists have not gained the courage to look in the face this coordinating/creating power evident in every organism, let alone to ask about its relation to inheritance. We have every right to ask whether the wise and living capacities through which the unity of the organism is sustained, and through which the materials of inheritance are brought into existence and assembled in a gamete, can themselves be counted among, or caused by, the heritable contents.

That may seem a strange question. But there is nothing wrong with acknowledging the constrictive boundaries of our current understanding. At present we scarcely know how to speak about such matters. But we shouldn’t have difficulty at least holding on to the observationally sound idea of the unity, wholeness, and distinctive character of every organism. Only by starting with what we observe can we work toward a deeper understanding.

One thing I believe we can say is this: the wholeness and character of an organism is most fully visible in its powers of directive or telos-realizing activity, not in the material results of this activity. And the activity always shows counter-balancing tendencies. In a developing organism we find ourselves looking at change within continuity — the ongoing transformation of an enduring unity. All the cell lineages (including the germ-cell lineage) undergo differentiation even as they continue to participate in the consistent, forward-facing, and adaptive way of being of the whole organism.

Change and continuity: every organic whole embodies — lives — a harmonization of these contrasting principles. But these are exactly the principles that any theory of evolution must somehow reconcile. 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”.

Some biologists might reply, “Why would we want to speak of the organism as a meaningful entity or being?” It really is just a mere material aggregate that happens by chance and natural selection to have the features it does”. But this is not honest, since every biologist, so far as she is doing biology and not physics, speaks of organisms as living beings with a recognizable, sustained, and consistent nature — and speaks with a vocabulary overflowing with the meaning of that nature. On this, see the discussion of a dog and its corpse in Chapter 2 (“The Organism’s Story”). If one felt oneself really to be speaking of a mere aggregate, one could no more talk about its evolution than one could talk about the evolution of an arbitrary scattering of pebbles upon a patch of ground.

Every organism in fact shows us the sort of reconciliation, or harmonization, of change and continuity that evolution requires. And yet, because the complex developing organism generates its stunning diversity of cell lineages after having received but a single inherited genome, we cannot point to random genetic changes, or mutations, as the explanation for the dramatic and observable differences between those lineages.3

The whole-cell transformation of a differentiating cell lineage (whether somatic or germline) just does not represent the kind of power evolutionary theorists are interested in. It is too living, too complex, too holistic — and therefore too difficult to analyze into a set of unambiguous, discrete causes. In the spirit of reducing the whole to experimentally tractable parts, theorists have, bizarrely, insisted on regarding sequence mutations in a few heritable molecules (germline DNA) as the primary or sole basis for all evolutionary change. They somehow feel more comfortable dealing with the neat, statistically manageable occurrence of supposedly particulate, difference-making mutations than they do when facing the transformative capacities of living beings.

On the face of it, the failure of biologists to explore the powerful explanatory potentials of the organism’s more-than-genetic, whole-cell capacity for directed change seems to reflect one of the most egregious and crippling blockages of thought in all the history of science. Why should a forward-looking, adaptive capacity, natural to all organic activity and powerfully evident in all the cell lineages of our bodies, cease altogether at just one decisive point: namely, the point where the germ cell lineage contributes a gamete to the next generation?

If anyone is appealing to mysticism or magic, presumably it is those who posit such an otherwise unexplained hiatus in the organism’s routine management of its differentiating cells. These all participate in the organism’s power to move directively toward a future state that is not at all rigidly determined by its current state. It is clear that every cell, every embryo, and (as the paleontological record so strongly suggests) every population of organisms possesses a nature that not only reflects the past, but also is continually expressing its own characteristic potentials for adaptive self-transformation.4

An extraordinary power

Here’s another way to think of it. In a young human embryo (as in all embryos of complex, multicellular organisms) there are slightly differentiated cells of many distinct types, called progenitor cells. Each progenitor cell has a tendency to differentiate into a particular type (or any one of a few types) of mature cell. Through a process of repeated division, it enlists all its resources, including its genes, in a journey leading to a distinctive “creature” — a living entity such as a muscle cell, a liver cell, a kidney cell, a skin cell, a neuron, and so on.

Now think of the zygote. It is formed from the fusion of two gametes, followed by their profound and living reorganization, a mutual adaptation through which the zygote becomes the progenitor of all progenitor cells in the new organism. This vast range of potentials, held by the zygote as a living organism, is actualized and manifested as a power of whole-organism metamorphosis involving all present and future cellular resources — first, in the zygote itself, and then in all descendent cells along their many lineage trajectories.

We can hardly help acknowledging the overwhelming reality of this power of transformation — a power that proves highly adaptive in the presence of novel circumstances, and a power that vividly demonstrates the organism’s ability to employ its one inherited genome in the service of radically divergent living entities (cells).

And yet, in the face of this reality, generations of biologists have almost unanimously declared that the only things passed through inheritance that can account for evolutionary change are differences (mutations) in the genetic sequence. The transformational power of the inherited cell as a whole, extending vastly beyond the influence of its genes, can, they’ve told us, be disregarded. All this without any effort actually to investigate the evolutionary significance of the power of the whole cell, and even with an occasional acknowledgment that “we wouldn’t know how to begin pursuing such an investigation”.

And this is the “settled science” that everyone interested in evolution is required to accept at risk of being called a “science-denier”?

The sort of complex, circular, “anything-potentially-affects-anything-else” causal interplay of whole cells and whole organisms is readily observable by every researcher, and has been recognized ever since Immanuel Kant first drove the point home in his Critique of Judgment in the late eighteenth century. So why has it been such a struggle, throughout the subsequent history of biology, for biologists to hold on to an awareness of the wholeness manifested in the structure and self-transforming activity of organisms? And why have evolutionary biologists allowed their judgment to be so distorted by a simplistic preoccupation with randomly mutated genes as difference-makers?

As we have seen, E. S. Russell rejected the gene fixation that has now bedeviled geneticists and evolutionists for a century. His work was part of a broad, international effort among many biologists during the first half of the twentieth century to found biology upon facts of the organism that anyone could see. But then came the “Modern Synthesis” with its gene-centered view of evolution, followed at mid-century by the molecular biological revolution, which, so it was thought, powerfully reinforced the gene-centered view of the organism. So the organism that anyone could see disappeared, giving way to an imagined organism viewed through a purely conceptual, gene-shaped lens. And with the triumph of the gene, the twentieth-century proponents of whole-organism biology were erased from biological narratives, except as quaint historical examples of “mystical” or “vitalist” thinking.

Has there ever been a greater example of willful refusal to face obvious, universally recognized truths within a major field of science?

How difficult is it to recognize
the principle of holism?

In 1978, and again in 1985, Harvard geneticist Richard Lewontin wrote that if an organism’s traits are to lend themselves to natural selection, they must be quasi-independent. That is, they must be changeable (subject to mutation) in at least some ways that do not dramatically alter other traits. This is because any such correlative alterations are very likely to be harmful to the organism. Think of it this way: if an organism is so thoroughly holistic that changing any one thing is likely to change many other things, then evolution in the direction of greater overall fitness would require a virtually impossible combination of beneficial mutations to different parts of the organism all at once, so that they might all be selected together.5 Such seems to be the prevailing view, anyway.

Lewontin’s “quasi-independent” criterion has been picked up by others, sometimes in order to make jabs against the idea of holism. Philosopher of biology Kim Sterelny, for example, has written that “It is hard to change developmental sequences if the development of any characteristic is linked to the development of many characteristics. For a change is likely to ramify, having many effects on the developed phenotype, and some of these are nearly certain to be deleterious”:

Thus, to the extent that development is holistic, the more complex the organism, and the more it has been elaborated over evolutionary time, the less significant further change there can be in that lineage. The point that adaptive change would be impossible if development were holistic has been made before. Lewontin, for example, has pointed out that such change requires traits to be “quasi-independent” … (Sterelny 2001).

There is something strange here. If an organism’s life and development is holistic in the manner that has so long been recognized, why should we suddenly lose sight of this holism as soon as we turn our attention to its evolution? Why, for example, should we abandon our faith in its holistic capacities when it comes to the preparation of a coherent inheritance for its offspring? And why should we lose sight of the developing organism’s remarkable capacity to integrate and reconcile as far as possible its various physical resources — or, for that matter, the equally remarkable capacity of two gametes to organize their separate lineage inheritances (each containing many “mutations” relative to the other) into a single, viable zygote?

It seems that the very idea of holism is so alien to biologists that the attempt to think it is aborted before it gets very far. This is all the more odd given that many of those repelled by the idea of holism in general are also (and with justification) enamored of the inescapably holistic idea of phenotypic plasticity — the organism’s ability to alter itself in order to adapt to a particular environment. If organisms are phenotypically plastic, then their different internal systems — for example, those involved in bone growth, muscle growth, and nerve growth — must be tightly integrated, so that they can respond adaptively and mutually to changes in each other. “Phenotypic plasticity”, we read in one enthusiastic author, “pre-adapts lineages to evolutionary change, by connecting the development of distinct organ systems”:

Limb development requires simultaneous and co-ordinated development in other organs and tissue systems: cartilage, muscle tissue and attachment points, innervation of soft tissues; circulatory connections to tissues and bone marrow. If bone structure or muscle mass is plastic, responding to signals from the environment, co-ordinated systems must be plastic too, responding to signals from the systems developing with them … This same sensitivity of integration to the contingencies of development will make functional integration possible in the face of genetically-caused changes in crucial organ systems.

The author of these remarks (Sterelny 2009) happens also to be the author of the comment above about the problem holism presents for evolutionary change. It’s as though, when one’s attention turns to evolution, one is obligated to begin thinking of change as if it were brought about, not by the character and agency of the organism, but by random disturbances to a mere aggregate of particulate genes that somehow map to and determine the organism’s phenotype. And, yes, it is then very hard to imagine a set of scattershot changes that would, in harmony, alter the intricately interwoven, holistic way of being of an organism. But once we have acknowledged an organism’s holistic nature — and, in particular, its capacity for holistic, adaptive change — why should we so quickly forget it, especially when, in evolutionary theory, we are actually addressing the issue of holism?

Perhaps Sterelny changed his mind between the writing of those two articles. In any case, I am not here saying anything about the degree of “quasi-independence” some organismal traits might have. Nor am I suggesting that evolution is equally possible for all species. For all we know, physically evident evolution may no longer be occurring in humans — or not occurring nearly as much as in previous evolutionary eras. It might be argued, after all, that in humans a major evolutionary transition is placing the power to direct evolution into our own hands. And this looks more like an evolution of consciousness than a further bodily evolution.6

As for “quasi-independent” traits and holism, I think Samuel Taylor Coleridge, writing in the mid-1800s, put the question into the right perspective:

“The living power will be most intense in that individual which, as a whole, has the greatest number of integral parts presupposed in it; when moreover, these integral parts, together with a proportional increase of their interdependence, as parts, have themselves most the character of wholes in the sphere occupied by them” (Coleridge 1848).

Or, re-phrased: Life will be fullest in the individual that most fully integrates the greatest number of parts; and when those parts are themselves most like wholes.

In other words, the potential for holism and the potential for a (relatively) independent perfection of parts are two sides of the same coin. An overall, deeper holism depends on a greater independence and perfection of parts in their own right, and a greater independence and perfection of parts depends on a deeper holism. The two principles do not push in opposite directions, but are complementary, with each requiring the other.

Coleridge’s remark derived, I believe, from a straightforward observation of living beings and requires no evolutionary theorizing. He was, of course, writing before Darwin’s Origin. And he was willing to look at whole organisms as they actually presented themselves. There is nothing in evolution that contradicts the most profound holism of organic life.

Where are we now?

When the Organism Was Seen Whole

During the first half of the twentieth century a considerable number of biologists, among whom E. S. Russell was a leading figure, sought to articulate a biology that kept the whole organism in view. We could, perhaps, call theirs a “common-sense view” since, as I argue throughout this book, all biologists even today reveal in their direct, observational language that they see the truth of the organism’s agency — its story-telling, directive, telos-realizing life — in a perfectly practical sense. (See Chapter 2, “The Organism’s Story”.)

A key point emphasized here is that inheritance is never anything other than whole-cell inheritance; we always find ourselves watching the uninterrupted life of whole, living entities. It happened, however, that the possibility of tracking and statistically analyzing the passage of genes from one generation to the next offered a possibility for the kind of logically clear, mathematized results that felt to most biologists “more like science” than did the difficult effort of acquainting themselves with the less clear-cut, qualitative, telos-realizing character of whole cells and whole organisms.

And yet, as Russell pointed out, this narrowed the biologist’s view down to the observation of some of the genetic causal factors playing into more or less minor differences between closely allied organisms, such as parents and their offspring. (Geneticists also learned to produce monstrosities, but these didn’t have a whole lot to teach about the evolutionary potentials of viable organisms.) On top of this, geneticists blithely ignored the multicellular organism’s dramatic capacity to orchestrate the “evolution” (differentiation) of numerous cell lineages that are, in their own terms, as phenotypically distinct as distantly related species.

The zygote of such an organism is master of a transformative power that can hardly be seen as less dramatic than the power at work within evolution as a whole. Nor does this power of development appear to differ in its fundamental nature from the power of change driving evolution. And we see nothing between generations that in any way interrupts the potential for adaptive change. The organism’s living, developmental capacity extends without a break not only up to the production of gametes, but all the way into the zygote and life cycle of the next generation. The underlying powers of life, revealed so dramatically in individual development, are continuous.

Further, the potential for development in a complex, multicellular organism reveals itself as a power to coordinate numerous, physically distinct cells, each with a life of its own, toward a more differentiated and mature state. This future-oriented power of coordination remains a complete mystery in relation to the explanatory principles biologists today are willing to acknowledge. It is obvious enough that, until this problem is engaged, we can have no grounds for dismissing the presence of the same sort of coordinating power at work among the numerous, physically distinct organisms in an evolving population. The transformation of an ancestral population into a new species through an evolutionary process already testifies to such a coordination fully as much as does the transformation of a horse embryo into a mature horse through a developmental process. On all this, see Chapter 19 (“Teleology and Evolution: Clearing Away Some Obstacles to Thought”) and Chapter 20 (“Development Writ Large”).

In the next chapter, I will try to pinpoint the decisive inclinations underlying what I am calling “the genetic distraction”, which has so powerfully wrenched the past century’s evolutionary biology away from any reckoning with the actual life of whole organisms.

Notes

1. On the relevance of Russell’s work today, see “Heredity, Development and Evolution: The Unmodern Synthesis of E. S. Russell” by Maurizio Esposito (2013).

2. Hybridization does in fact sometimes occur between distinctly different species (within limits) and, as I mentioned in Chapter 20 (“Development Writ Large”), it is possible that this contributes to rather dramatic evolutionary change. But such hybridization is likely to generate massive genetic and cellular reorganization, far too extensive and global to allow for conventional genetic approaches. So one is still facing the unsolved “problem of the whole” — the problem that genetic analyses were designed to steer clear of by focusing on particular genes causing particular trait differences.

3. Evolutionists are interested in germline (heritable) genetic mutations as the primary basis for evolutionary change. No one will quarrel with the fact that we lack any such germline mutational basis for the very great changes that can occur in the differentiating cell lineages of a complex, multicellular organism. (See Chapter 18.) But we can ask whether there are non-germline (“somatic”) mutations along the various paths of cellular differentiation, and whether these are important for the success of differentiation. The question is being actively explored today. But we can already say this much: to whatever degree somatic mutations do occur and are important to cell differentiation, the fact would show that the organism manages and directs its own genetic mutations. Why? Because cell differentiation (and development in general) are such obviously directive processes, and are universally recognized as such. If mutations were an essential part of these processes, we could hardly believe they play their roles in a random manner relative to the overall trajectory of development.

4. I have never seen an evolutionary biologist even acknowledge the possible legitimacy of an inquiry into the whole-organism transformative capacity of germ cells or gametes. They certainly do not seem inclined to cite evidence for anything of the kind, or even to pay much attention to the fact that the development and specialization of the germ cell lineage is at least as dramatic and well-directed as the differentiation of any other forward-looking cell lineage in complex organisms (and all differentiating cell lineages are forward-looking). But, just as important, the claim of “no evidence” for more-than-genetic, whole-cell inheritance, when it is made, usually reveals itself as spectacularly circular, being based on the argument that, whatever the whole-cell transformation we witness in germ cell lineages, we don’t see corresponding changes in the genetic sequence. That’s the argument that surfaces so often when the question of transgenerational epigenetic inheritance is raised. In other words, an insistent assumption that all heritable change must take the form of germline genetic mutations — or at least be closely analogous to them — is being used to refute the claim that there is more-than-genetic, whole-cell, heritable change. (See Chapter 18, “Evolution Writ Small”, for a discussion of the curious idea that evolutionary change depends on the stability — unchanging nature — of already achieved mutations.)

When confronted with the problem of the character of the whole cell, biologists have a tendency to cite the impossibility of carrying out their usual analyses wherever one insists on speaking of “wholes”. In self-defense they sometimes add that the very idea of a whole invites vitalist or mystical thinking. (See the section, “How difficult is it to recognize the principle of holism?” below.) And so there has never been a major research program aimed at tracking how whole-cell inheritance might play into evolution. The most obvious possibility is the least considered — because it poses the problem of the “mystical” complexity of actual organisms.

5. See Lewontin 1978 and Levins and Lewontin 1985. In the latter work the authors wrote:

By quasi-independence we mean that there exists a large variety of paths by which a given character may change; although some of these paths may give rise to countervailing changes in other organs and in other aspects of the ecological relations of the organism, in a reasonable proportion of cases the countervailing effects will not be of sufficient magnitude to overcome the increase in fitness from the adaptation. In genetic terms, quasi-independence means that a variety of mutations may occur, all with the same effect on the primary character but with different effects on other characters, and that some set of these changes will not be at a net disadvantage. (p.80)

6. German philosopher, Dieter Wandschneider, has commented that “In a world in which sickness can effectively be cured, clinics and spas are at people’s disposal, artificial limbs are applied, and replacement organs are implanted, the biological principle of [Darwin, in its modern form] has been ‘unhinged’”:

One could object that the human species changes biologically even today — for example, in muscle structure, susceptibility to sickness, and life span. That cannot be denied. But these changes are manifestations of the “self-domestication” of man and thus consequences of civilization, which as such are not the results of natural selection. On the contrary, they are expressions of an evolution that is now taking place under completely different conditions, namely those of cultural evolution (Wandschneider 2005, p. 204).
Tags: evolution/and development; evolution/inheritance; evolution/and mutations; gene/as difference-maker; holism

Sources:

Coleridge, Samuel Taylor (1848). Formation of a More Comprehensive Theory of Life, edited by Seth B. Watson. London: John Churchill. Facsimile edition from Ann Arbor MI: UMI Books on Demand.

Esposito, Maurizio (2013). “Heredity, Development and Evolution: The Unmodern Synthesis of E. S. Russell”, Theory in Biosciences vol. 132, no. 3 (Sep.), pp. 165-80. doi:10.1007/s12064-013-0177-4

Johannsen, Wilhelm. (1923). “Some Remarks about Units in Heredity”, Hereditas vol. 4, pp. 133-41.

Levins, Richard and Richard Lewontin (1985). The Dialectical Biologist. Cambridge MA: Harvard University Press.

Lewontin, Richard C. (1978). “Adaptation”, Scientific American vol. 239, no. 3 (September), pp. 212-30.

Oyama, Susan, Paul E. Griffiths and Russell D. Gray, editors (2001). Cycles of Contingency: Developmental Systems and Evolution. Cambridge MA: MIT Press.

Russell, E. S. (1930). The Interpretation of Development and Heredity: A Study in Biological Method. Reprinted in 1972. Freeport NY: Books for Libraries Press.

Sterelny, Kim (2001). “Niche Construction, Developmental Systems, and the Extended Replicator”, in Oyama, Griffiths and Gray 2001, pp. 333-49.

Sterelny, Kim (2009). “Novelty, Plasticity and Niche Construction: The Influence of Phenotypic Variation on Evolution, Mapping the Future of Biology, pp. 93–110. doi:10.1007/978-1-4020-9636-5_7

Wandschneider, Dieter (2005). “On the Problem of Direction and Goal in Biological Evolution”, in Darwinism and Philosophy, edited by Vittorio Hösle and Christian Illies, pp. 196-215. Notre Dame IN: University of Notre Dame Press.

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Steve Talbott :: Inheritance (1): The Whole Organism