Nature does not choose

We want, but nothing wanted us to want. This should have been clear since Darwin; or at least it should be clear that it is possible to think in this way, since this is the meaning of Darwin's work, a work to which the vast majority of scientists lay claim. However, as soon as we ask these scientists about Darwinism, we come up against words whose overall effect is to nullify Darwinism; words that take us right back to finalism, to before Darwin, to the time when Darwin was almost alone in fighting for these ideas. In particular, if today's biologists are asked how we animals came to be, they reply, in the words of Darwin himself, that nature acted by natural selection.

It should be possible to talk about biology without finalism. But the persistence and omnipresence of finalist terminology is still a major problem today, despite the open Darwinism of almost all biologists. I have already dealt with the essentialism inherent in the use of the word “species”2 and I will dwell at length here on the finalism of this central expression “natural selection”; to make the suffocating omnipresence of finalism clear, however, I will first give a few other examples.

We are hardly aware of the finalism behind our words. We say and hear phrases like “Titabills mate in February so that their young are born in May and enjoy the fine weather” without batting an eyelid. But do titabills have the slightest idea of the length of their gestation period? Common thinking, which denies all feeling and intelligence to non-humans when it suits it, sometimes grants them calculating and predictive abilities as well as completely implausible intentions. In fact, this common, speciesist way of thinking once again denies the individual reality of non-humans; it says “titabills”, but in fact thinks “the titabill species”, “natural finalism in its titabill incarnation”. For her, individual titabills exist only as representatives3.

Finalism is also expressed in functionalist language. For example, we might say “the thorns allow the plant to defend itself against birds”. But the verb “allow” implies a will on the part of the plant: it wants to defend itself; reality poses obstacles; the thorns allow it to remove them, they are a means to an end. The plant wants to defend itself, to defend its life; its life is of value to it.

We have known since Darwin, or we should have known, that things don't work like that; or at least that there is a simpler explanation, one that allows us to dispense with the a priori implausible attribution of a will, a conscience, to the plant. We can suppose that at a certain point, certain plants had, for some reason, something resembling thorns; as a result, birds ate them less, they produced more seeds and gradually spread, whereas others, which did not have thorns, produced fewer seeds and left no descendants. Of the former, those with the largest or hardest thorns were themselves eaten less by birds, and so by the same mechanism plants with large, hard thorns became more widespread.

This is the mechanism described by Darwin; I have explained it in an attempt to rigorously eliminate any finalistic expression. If I had not made this effort, I would have said, for example, as everyone else does: “...as this protected these plants from attacks by birds, they had greater reproductive success and gained the upper hand over their competitors”; I would have denied five times over the mechanical character that I had set out to highlight!

Is this an inevitability of the language? I think it's more a sign of our difficulty, our reluctance, to truly integrate Darwinism, more than a century after The Origin of Species, and this despite the open adherence of most biologists to the words of the Master.

The (barely) hidden finalism of the expression “natural selection”

 

See this excerpt of a 1866 letter from Alfred Wallace to Darwin which carries essentially the same criticism against the term “natural selection” (source: Richard Dawkins, The Extended Phenotype, pp. 179 and 180).

Everyone remembers that Darwin used the expression “natural selection”, but few remember that he only justified it by analogy: “I have given this principle (...) the name of natural selection, to indicate the relations of this selection to that which man can accomplish”4. It is marked by his intellectual development, for it was largely through the study of the selection practised by breeders on domestic animals that he arrived at his theory. It therefore reflects a period when Darwin was not yet a Darwinian. Moreover, it did not satisfy Darwin himself, who immediately added that another expression would have been more accurate. But it satisfied everyone after Darwin. We preferred to live with it.

Let's use an example to analyse what selection is.

1. I've shelled some peas and piled them in a salad bowl. I'm a gourmet, but I'd like to reject the meatiest ones.

2. I know that the meatiest peas are also generally the largest. So I sort them and keep only the smallest. I can sort them by hand or with a sieve, it doesn't matter; the main thing is that I have one selection objective – non-starchy peas – and one selection criterion – size. I select the peas according to the criterion and with a view to the objective.

3. At the end of the day, I end up with a good dish of tender peas, even if perhaps some of them, despite their small size, turn out to be mealy.

There is no coincidence between the selection objective and the selection criterion. The selection objective (taste) is my objective, the result of the desires and interests of a sentient being. The selection criterion (size) is directly material, and can be implemented entirely mechanically (sieve). I wanted it to be as faithful a material translation of the selection objective as possible (“I know that the meatiest peas are also generally the biggest”), but there may still be a discrepancy. The selection may be wrong, or more precisely, I may be wrong in choosing my selection criterion.

Let's look at another example, where there is no real selection:

An explosive volcanic eruption throws huge boulders into the area around the crater. Once the powers of hell have calmed down, a team of vulcanologists goes to the site and notices a certain gradation in the size of the blocks: the further away from the mouth of the volcano, the smaller they get. Perhaps this seemed quite natural to them, and perhaps they suggested a physical explanation, based for example on the relationship between the force exerted on a block, proportional to its cross-section, and its mass, proportional to its volume. On the way back, however, the expedition found a particularly large block far from the crater. The scientists wrote down this fact in their notebooks, and wondered how to fit it into their explanation.

No one, however, thinks that the god Vulcan has made a mistake. It didn't even occur to the vulcanologists that someone had tried to sort the blocks. Something had happened that had resulted in a certain distribution of the blocks; as the phenomenon is complex, so is the resulting distribution, even if, to begin with, we can simplify things by saying that the largest blocks were thrown less far. The result is not to be compared with some objective; the process could not have been wrong, because being wrong is always in relation to something we would have liked. The process is not a selection; it is what it is. It cannot disappoint the forces that set it in motion; at most it can disappoint the vulcanologists.

So, for a process to be a selection, it is not enough for it to be a process, producing a certain result; there must be a purpose, a selection objective, of which the process is merely the implementation. Now, as I said, the central contribution of Darwin's work lies in explaining evolution as a mechanical process, devoid of purpose; it is therefore inappropriate, even contradictory, to retain the expression “natural selection”.

I said that Darwin chose this expression by analogy. This is because the process it describes is very similar not to selection in general, but to that of breeders:

A breeder wants cows that give a lot of milk. He knows that, generally speaking, children tend to resemble their parents. So he will keep the daughters born of the most productive cows; the others he will send to the slaughterhouse5. In fact, of the daughters he kept, many gave him satisfaction, some even more than their mothers; a few, on the other hand, disappointed him. Of the latter, he will eliminate the offspring.

The breeder thus has a selection objective (the quantity of milk the daughters will give), from which he derives a selection criterion (the quantity of milk given by the mother). It is therefore a real selection, a finalised process. But what is the analogy between this process and the one he called “natural selection”?

To see this, we need to turn to the positive aspect of Darwinian theory, to its falsifiable postulates6. I will try to set them out here:

G1. The characteristics of living beings are generally transmitted to their descendants7 ; there is, however, a certain amount of variability, since descendants never resemble their parents exactly. At least part of this variability is itself transmissible, i.e. in an individual, even a new trait can be passed on to its descendants.

G2. At least part of this transmissible variability is random, i.e. its appearance is independent of any purpose.

G3. There are cases where random transmissible variability influences, in a given environment, the average number of descendants of the individual (more exactly: the mathematical expectation of this number). If the environment remains the same, the frequency of these traits in the population will tend to increase or decrease depending on whether they increase or decrease the average number of descendants.

G4. This process is sufficient to explain the evolution and transformation of living forms over the course of the Earth's history.

There is a strong similarity between breeder selection and “natural selection”:

E1. The daughters of very productive cows are themselves generally very productive; however, the breeder knows that this is not an absolutely reliable rule: there is an element of variability. This variability is sometimes transmissible, which is why the breeder will look first and foremost at the qualities of the dam, rather than those of the granddam (i.e. take into account newly-arrived traits), when deciding whether to keep the daughters or have them killed.

E2. The breeder knows from which dams he chooses to keep the daughters, but he also knows that he does not control the exact traits of these daughters. He may be lucky, he may not.

E3. The breeder will systematically ensure that the most productive cows, including those in which this productivity is a new trait (not inherited from their dam), have more offspring (not quickly destined for slaughter). As breeders have been doing this for centuries, cows become more and more productive.

E4. It seems plausible that this process could explain the marked difference between domesticated animals and their closest wild relatives.

Thus the parallel extends to the four points I have outlined. In these conditions, it is understandable that Darwin wanted to recall the practice of breeders in the title of his theory. In fact, the selection of breeders E1-E4 appears to be a simple special case of the general process G1-G4, the objectives of the breeder constituting a special case of environment in which a random transmissible variability influences the average number of descendants of the individual (points G3 and E3). Quite simply, the breeder acts with intention, making the process a real selection. Darwin's mistake was to use a term that applied only to a particular case to designate the general case.

This was quite logical on his part, especially as it is a common linguistic procedure. In French, we say “limoger quelqu'un” since some generals, I believe, were sent on forced retreat to Limoges. So, yes, “natural selection” is a good formula, as long as it's understood in that sense.

Unfortunately, it has not remained just a formula. It's as if, today, those who talk about “natural selection” believe in it as much as if they thought that all the employees who have been sacked ended up in Limoges. Here is a description of “natural selection”, as it is still perceived:

In order to promote a certain number of qualities – strength, speed, intelligence, beauty, etc. – In order to promote a certain number of qualities – strength, speed, intelligence, beauty, etc. – nature sets in motion a process of selection, through which it eliminates “the weak, the mentally debilitated, the counterfeit”, as A. Lindbergh8. For example, by instilling an instinct for sexual competition in male deer, it leads them to compete with each other, so that the stronger ones reproduce more and supplant the weak, the mentally retarded and so on.

To see the presence of the disjunction between selection criterion and objective in such a description, we need only imagine that a stag learns to “cheat”; that it is given the means, for example, to coat the tips of its antlers with a toxic substance that neutralises its opponents on first contact. This stag, however scrawny and wobbly it may be, will win every fight and leave a large number of similarly “counterfeit” offspring. It will pass the selection criterion – winning fights – even though it does not meet the selection objective – strength. It will be said that he has cheated because he has not obeyed the rules of competition, which Nature instituted “so that the best man wins”. So, in common thinking, the best is not by definition the one who wins; there is an a priori best, corresponding to the selection objective, and a winner, corresponding to the criterion.

How can a deer learn to cheat? Yet it is “cheating” that goes a long way towards explaining the contempt that biologists (and almost everyone else, in fact) sometimes openly express for a large number of beings, to which they apply the beautiful name of “parasites”9:

✓A price has been paid during the course of evolution for this achievement in perversity. The mark of the parasite is upon the Teleutomyrmex; their bodies are weak and degenerate10.

Another example of “cheating”: the poor, the homeless, the human unemployed, the “weak, the mentally retarded, the counterfeit” whom “no natural selection can eliminate”. We “jealously keep them alive”, “that's the way it has to be in civilisations like ours”; but A. Lindbergh, who says this11 , is also “an unconditional supporter of natural selection, because Nature can't make mistakes”. Can't make a mistake... A fine assurance, but one that clearly shows that for A. Lindbergh, as indeed for everyone12, it is at least conceptually conceivable that Nature makes mistakes. She's not saying “it makes no sense to say that Nature makes mistakes”; she's saying that Nature is wise enough to ensure that its selection criterion corresponds to its selection objective. Except when “civilisation”, Man and artifice come into play: that's what allows the weak to cheat, and so on.

We need a history of Darwinism up to the present day, a history of the immediate recovery of Darwinism by the right, through “social Darwinism”. The left has mobilised a great deal against this, on the theme of “it's not the same, humans are humans, not animals”. It would have been better if they had simply said, “Social Darwinism is not Darwinism. It has nothing to do with it”. She could have started by showing that “natural selection” is not selection. But she didn't do that, she missed the boat on Darwinism, because she too was mired in finalism, naturalism, which she didn't want to abandon, because she was a speciesist13.