The Selfless Machine

 

 

The Selfless Machine

 

In a striking passage from The Selfish Gene Richard Dawkins writes as follows: “Other replicators perhaps discovered how to protect themselves, either chemically, or by building a physical wall of protein around themselves. This may have been how the first living cells appeared. Replicators began not merely to exist, but to construct for themselves containers, vehicles for their continued existence. The replicators that survived were the ones that built survival machines for themselves to live in. The first survival machines probably consisted of nothing more than a protective coat. But making a living got steadily harder as new rivals arose with better and more effective survival machines. Survival machines got bigger and more elaborate, and the process was cumulative and progressive.”[1] He goes on to say of these encased replicators: “They are in you and me; they created us, body and mind; and their preservation is the ultimate rationale for our existence. They have come a long way, these replicators. Now they go by the name of genes, and we are their survival machines”. This is the core of the “selfish gene” perspective: animal bodies (and minds) are the selfless conveyors of selfish genes into future generations. Organisms are artifacts constructed by genes to get themselves propagated. Dawkins is obviously thinking of the survival machines consciously constructed by humans (but obviously not consciously constructed by genes): houses, clothes, weapons, body armor, heating systems, etc. We construct artifacts that aid our survival, and genes do much the same. Their survival machines are squishy, organic, and sometimes conscious, while ours are dry, mechanical, and unconscious (so far at least): but the logic is the same—survival-enhancing devices. He could equally have spoken of survival kits or suits or sheaths or vehicles or pods or crafts or envelopes—the idea is just that of a complex entity that contains the replicators and enables them to reproduce safely. Thus a bodily trait is functionally just like a spider’s web or a beaver’s dam: it is a device for increasing the probability of gene survival in a competitive world. The spider’s genes are machines for making other machines (spider bodies), and these machines make still other machines (spider webs). The genes are the architects and beneficiaries of organisms, which in turn are the architects and beneficiaries of bits of external machinery (nests, burrows, mounds, tools, etc.) Genes are indirectly the producers of these bits of machinery, because they build organisms that build these bits. The external machinery is not selfish, as organisms are not selfish (in the technical sense of “selfish”); these things work to aid the selfish genes. They are selfless machines working for selfish genes.

If we add the extended phenotype to this picture, we can say that the genes build survival machines that incorporate both bodies and the external products of bodies (as well as minds in some cases)—webs as well as spiders. It might seem that this is a rather limited class of cases, since many animals don’t create anything tool-like. But closer examination reveals that actually extended phenotype is the rule not the exception, since animals modify their environment in myriad ways the better to aid survival. Many animals dig holes and these act as useful survival devices (so do plants with their roots). Animals tend to prepare their food before ingestion by chewing, chopping up, ripping, or infusing saliva. Birds use twigs as benches as well as build nests. Snakes use friction between themselves and the ground to propel themselves forward. Cats use spatial proximity to catch prey.[2] Fish use water to push their fins against. Organisms take advantage of the environment external to them in order to aid their survival: sometimes they actively construct useful artifacts and sometimes they find them already in existence. The survival machine includes all the facts that promote gene survival, extending out into the environment. It is arbitrary to locate a cut-off point at the animal’s epidermis. Put differently, the genes must take into account the environment external to the organism as well as to the organism itself when building a good survival machine. Natural selection favors good webs, but it also operates with hospitable found objects: it selects organism-environment combinations. A house includes not just the walls but the spaces in between, as well as proximity to water, etc. The phenotype is always extended in some way. In any case, external machinery should be reckoned to the machines the genes have created, as suggested by the extended phenotype. The phenotype survival machine built by the genotype is an extended phenotype survival machine.

So far this is pure Dawkins, stated in other language: it’s all selfish genes, selfless survival machines, and extended phenotypes. Now I want to venture further afield and push this perspective a little harder. The first question is whether the gene is the end of the line: might genes be survival machines for something else? Webs are survival machines for spiders, and spiders are survival machines for genes, but are genes survival machines for another type of entity? Do they function so as to keep something else in existence? Does their survival promote the survival of an even more basic biological entity? What about the chemicals that make them up? If a chemically complex gene survives, so does its chemical components—they become more common than potential rivals. So maybe the components of genes are entities that benefit from the survival of whole genes—selfish gene parts. After all, if a human machine proliferates, so do its parts: the more BMW cars there are in the world the more BMW car components there are in the world. The preservation of whole cars leads to the preservation of parts of cars (say, a particular type of hood). Thus we arrive at the idea of the selfish molecule. Second, isn’t it at least logically possible that we don’t know everything about genes, and lurking within them is some new kind of entity that shapes them? Maybe there exist more basic biological units that construct DNA sequences, so that the survival of DNA sequences ensures the survival of the more basic units. There is no reason that I know of to believe this is actually true, but its mere logical possibility shows that the gene is not necessarily the end of the line. Physicists keep discovering new and more basic particles: is it inconceivable that geneticists might discover even more basic genetic units? But third—and this is the point on which I wish to place particular emphasis—can’t we say that genes are the product of the process of natural selection, so that that process is the most biologically basic reality? For genes enable that processto survive: no genes, no organisms, and so no process of natural selection. Natural selection builds genes and without them it—that process–cannot exist: its very survival depends on the survival of genes. If natural selection started producing dud genes, ones that fail to build bodies that get the genes propagated, then the whole process would grind to a sickening halt—with nothing biological left. There is no process of natural selection on planets that contain no genes (or some equivalent): the process needs genes (replicators) if it is to gain a foothold. Looked at this way the genes function as devices for keeping natural selection around. So natural selection had better build good genes or it will go extinct. If we picture natural selection as a tinker whose livelihood depends on good gene tinkering, then an incompetent tinker is not long for this world—he goes to Valhalla if he produces bad tinkering work. Similarly, the process of natural selection depends for its survival on good gene construction (the kind that leads to robust organisms): the genes act as survival machines for that process. Genes are artifacts of that process, as organisms are artifacts of genes, and as tools are artifacts of animals. So the chain of production leads back to natural selection: it is the driving force of evolution, and genes act as its survival-enhancing devices. Natural selection is thus the ultimate “selfish” biological reality. To put it anthropomorphically, the genes are the indispensable servants or slaves of the process of natural selection: if they fail, it fails; if they die, it dies. The more genes there are the more natural selection there is, as the more organisms there are the more genes there are. It is in the “interests” of the process of natural selection that genes should survive, as it is in the “interests” of the genes that organisms should survive. We have existence-dependence at multiple levels: the spiders need the webs to survive, the genes need the spiders (and the webs) to survive, and natural selection needs the genes to survive (as well as the spiders and the webs). There is thus a whole hierarchy of survival machines terminating in the process of natural selection. Natural selection is the biological reality—the ultimate basis of the whole shebang. To paraphrase Dawkins, the process of natural selection, which may have looked paltry in the beginning, has gone far in its multi-million year history on earth, producing some remarkable survival machines. The DNA molecule itself is an impressive vehicle for the continuance of natural selection—it has enabled natural selection to colonize every corner of the planet. Natural selection now flourishes everywhere, while millions of years ago it was relatively confined and primitive. The gene was one of its greatest inventions, providing an excellent vehicle for it to travel far and wide. It is what has multiplied and proliferated beyond all imagining, aided by the trusty gene: without the gene (specifically DNA) it might have gone nowhere. If we think of natural selection as a species of process, comparable to species of chemical processes, then we can say that it is one of the most widespread species of process in the world. The genes are proud to have acted as its survival method. By building better bodies they improved its prospects dramatically by improving their own prospects. They gave natural selection a chance to operate widely and ingeniously; without them it would be eking out a living at a very low level of replication. The genes have maximized the spread of natural selection—as organisms have maximized the spread of genes. The logic is the same in both cases, though the entities are very different. Genes are complexes of molecules while natural selection is an abstract process. Complex molecules have enabled an abstract process to become an entrenched feature of planet earth. It is almost as if natural selection consciously designed them with that purpose in mind—as it can seem like the genes were conscious designers too. But no, in both cases we just have a mindless mechanical system following its own inevitable logic. It all follows from the very nature of natural selection as an abstract creative process.

Now that we are expanding the conceptual scheme of foundational biology let us revisit the extended phenotype. That was a good insight into the arbitrary nature of what might be called narrow phenotype—the kind limited to the animal’s body. The functional unit is really the body plus its adaptive effects (spider plus web); we could even reckon the web to be part of the extended body of the spider—it is that body spread out a bit further. But what about the genotype—must it be understood narrowly? Is the genotype confined by the boundaries of the DNA? It is telling that we regularly speak of genes by referring to their effects: genes for the kidneys, genes for the heart, and genes for the brain. We identify the gene by reference to the phenotypic trait it produces not by reference to its molecular composition. So why not work with the idea of the extended genotype? Why not take the bodily trait the gene produces to be part of the gene, as the web is part of the spider (i.e. its phenotype)? Not indeed part of the chemical composition of the DNA molecule, but part of a functional unit comprising molecule and bodily trait. Dawkins speaks of the “long arm of the gene”: yes, and it extends to the body it constructs in embryogenesis. The organism has a long arm, reaching to its adaptive artifacts; well, the gene reaches out that way too, to include its adaptive phenotype. Let’s call the external artifacts of an organism its “exotype”: then we can say that phenotype includes exotype and genotype includes phenotype—which includes exotype. By transitivity, genotype includes exotype—the web is part of the gene! That is, we reconfigure the boundaries of the gene so as to incorporate the external effects of the gene: the wide gene, as we might call it. There is the narrow body (spider alone) and the wide body (spider plus web); likewise there is the narrow gene (DNA) and the wide gene (DNA plus phenotypic trait). The canonical form of a wide gene description is thus “gene for X”, where X is some adaptive trait of the body or its products. It is the functional unit that is selected for by natural selection—a molecule plus the trait produced by that molecule (with accompanying apparatus). We thus insert the survival machine into the gene, widely construed—just as we insert the survival machinery of the exotype into the phenotype, widely construed. The web becomes part of the spider; the spider becomes part of the genes, or its traits do. We still have the narrow gene and the narrow spider in our ontology, but for theoretical purposes we also recognize another level of description that blurs such boundaries. If we imagine another biological world in which the same molecules are coupled with different traits, by virtue of different laws obtaining in that world, then we can see the point of carving things up this way: for in this world the same narrow genes will have different phenotypic expression, which obviously affects survival value. The same narrow gene will be adaptive in our world but not in this different world, given that it produces different disadvantageous traits. But if we individuate the gene widely we can say that adaptive value is preserved, since these are different genes in that world: the body comes along with the (wide) gene. What types of genes exist in a given biological world? Are they chemical types or trait-dependent types? If the latter, we only have the same genes when the traits are included in the total package—the extended genotype. Given that we are already comfortable with the extended phenotype, I see no reason why we shouldn’t accept the extended genotype (while retaining the narrow genotype—the gene without its long arm).

The initial replicators built their survival machines and even added external devices to enhance their survival capabilities. But later they recognized that they had merged with their machines and become extended beings. It is the same with spiders and webs: the initial spider built its web machinery and then stood proudly back admiring its handiwork. But later it recognized that it and the web were parts of a larger whole—it had merged with its web. The web survival machine became part of what the spider is—not significantly different from its legs and jaws. Similarly, the replicators were not just sitting snugly inside a survival machine but had joined forces with it: they were made up of bodily traits as well as tightly localized chemicals. To avoid confusion we might introduce a new term, since “gene” has become so strongly associated with spatially confined chemicals: we could call the entire complex of chemical material and bodily trait the “trene”, a combination of “trait” and “gene”. So trenes get selected by natural selection, just as combinations of spiders and webs get so selected. Trenes constitute the extended genotype. Organisms are collections of trenes, i.e. DNA molecules plus their associated bodily traits. A given trene would include, for example, a specific molecule in the spider’s DNA, a set of anatomical characteristics, and a distinctive type of web: this is what gets selected by natural selection (“selective holism”) not each of its components alone. Reverting to the point about natural selection as a beneficiary of the genes, we can say that natural selection builds survival machines with three main components: DNA, bodily traits, and external artifacts. Thus the process of natural selection survives because it builds machines that incorporate these three elements—that is, collections of trenes. Natural selection keeps going, keeps proliferating, because this is a good design for a survival machine—better than just bare replicators and better than organisms that can’t make anything. We ourselves, then, with our DNA, bodies, minds, and artifacts are vehicles for the continued existence of the process of natural selection.[3] We have become accustomed to thinking of ourselves as survival machines for our genes, but actually we and our genes are survival machines for an underlying biological process. We exist in all our glory because natural selection built us so that it could survive and flourish. We are the machines needed to allow natural selection to keep a foothold. We thus join the vast array of organisms on earth, from plants to people, bacteria to bats, whose job in life is to keep natural selection going. We are the devices invented by this abstract process so that it can survive. Natural selection created the gene (a certain type of replicator) and the gene created us (a certain type of reproducer): everything in the biological world is a survival machine for mindless natural selection to remain in existence and expand its domain. This is the ultimate rationale (to use Dawkins’ words) for the whole biological world. If you thought gene survival was desiccated enough, then natural selection survival surely brings desiccation to a new level. Even the mighty gene is made to feel secondary in the great scheme of things.

 

[1] The Selfish Gene (1989), pp.19-20. I am going to assume the perspective of this book in what follows.

[2] We could also say that cats use the device of injury in order to secure their prey: their teeth construct an injury that spells the demise of the prey animal. In the case of many big cats they use the windpipe of the prey as a device to subdue it, which is not fundamentally different from throwing a lasso around its neck. The environment takes on a function for the cat in its pursuit of food.

[3] This is not to say that we are only that—which is why I didn’t say we are just such vehicles. This is just one of the things we are, though quite an important thing. We are also moral beings, creative forces, free agents, romantic partners, scientists, etc. But from the point of view of biology we are the survival machines (conscious ones!) of the impersonal process of natural selection. This is ultimately why we exist.

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