New Version of Natural Selection Goes Mystical
Was there ever a song and dance as fantastical as W. Ford Doolittle’s ITSNTS proposal?
Yesterday, we took a look at the critique of evolutionary natural selection (ENS) in PNAS by W. Ford Doolittle and Andrew Inkpen. These two Darwinians are well versed in the controversies over ENS, having watched numerous versions parade by over the decades: kin selection, group selection, niche construction, inclusive fitness, neutral evolution, stabilizing selection, holobiosis, and more. They’ve listened to arguments over the meanings of fitness, adaptation, and selection. They’ve pondered the controversy over “units of selection” – the entities on which selection acts. They know evolution in and out, from its vision of proteins to its grand scenarios about the biosphere. And they’ve seen critics ask if natural selection is a law of nature at all, or just a restatement of happenstance or a priori reasoning. They can’t leave the situation in a mess like this. The Darwin show must go on!
And so they make a proposal: “ITSNTS thinking” about evolution (we’ll define that shortly). They know that Darwin Party elder Richard Lewontin laid down the rules for understanding natural selection. “Standard ENS” (evolutionary natural selection) must meet three requirements:
(i) There is variation in morphological, physiological, and behavioral traits among members of a species (the principle of variation). (ii) The variation is in part heritable, so that individuals resemble their relations more than they resemble unrelated individuals and, in particular, offspring resemble their parents (the principle of heredity). (iii) Different variants leave different numbers of offspring either in immediate or remote generations (the principle of differential fitness).
Lewontin believed these conditions are necessary and sufficient for ENS, even though they also fit the Stuff Happens Law. Lewontin, by defining fitness in terms of survival, also fell into the tautology trap by equating fitness to reproduction (see “Fitness for Dummies,” 19 June 2014). Lewontin’s version also fails to account for the origin of novel structures, such as wings and eyes.
Godfrey-Smith further restricted natural selection by warning, “there must be some parent–offspring similarity, and the clarity of a ‘parent-offspring’ relation of the relevant kind is inversely related to the number of parents—if there are too many parents there are no parents at all.” Any “selection” that occurs, in his view, must involve clear parent-offspring relations. But in his view of natural selection, he too failed to explain the origin of complex novelties. He reduces natural selection to little more than change: “Evolution by natural selection is change in a population owing to variation, heredity and differential reproductive success.” This makes extinction of the whole population a legitimate effect of natural selection as much as major leaps upward in complexity. That’s not quite what Darwin had in mind.
Doolittle’s “ITSNTS Thinking” Proposal
With that background, are you ready for Doolittle and Inkpen’s proposal to save natural selection? Can they unite the warring factions? Can they harmonize the simple cases with the complex cases? Can they re-“Darwinize” the mechanism that made Darwin famous? Here it comes: “Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking.” What is ITSNTS? Here comes:
ITSNTS = “It’s the Song, Not the Singer”
This had better be a good show. Let’s try to understand it before we applaud or boo. Doolittle envisions a persistent process rather than a persistent population of individuals. The process (the song) goes on, whether or not the individuals carrying the tune (the singers) change. “If there’s a song, there are singers.” Conversely, when we see individual organisms or groups following familiar patterns of behavior, we can see themes persisting through time behind their activities. “If there are singers, there’s a song.” How on earth did Doolittle come up with this genius idea? How is it not circular?
Well, it all started when critics of standard ENS found exceptions to it, like stable populations of symbiotic populations (e.g., gut biota), and processes that increase the fitness of the group at the expense of the individual (such as in the “evolution of altruism” or in social insect communities, where individuals incapable of reproduction do all the work). And then, there were some mystics trying to apply natural selection to the whole biosphere, invoking visions of the goddess Gaia. Knowing the controversies such cases generated between the mystics, the group-selectionists and the diehard neo-Darwinians, Doolittle looked for common ground. Let’s give Doolittle and Inkpen space to describe the peace treaty:
It is for the same reason problematic to speak of adaptation of multiparental communities formed by recruitment or re-production. Sober and Wilson recommend what they call “William’s Principle”—that “adaptation at a level requires that there was selection at that level”—noting that “[t]he fact that a trait now benefits groups does not entail that it evolved because it was beneficial to groups.” Indeed, it is not clear that any property can be considered “beneficial” to impermanent and nonreproducing communities. These might come to show traits of interest to or valued by us as researchers or citizens, such as functional stability, or resilience, or “eubiosis” (in the case of the “holobiont” that is us and our gut microbiomes), these being the indirect byproducts of “lower-level” processes. But without some form of differential reproduction or differential and continuous physical persistence, these traits cannot be considered adaptations for communities if anything resembling Lewontin’s recipe is to be applied.
ITSNTS theory seeks to rationalize (or “Darwinize”) such indirect “beneficial” outcomes, casting these not as adaptations for the individuals or collectives that implement a process, but for the process itself. Indeed, it was initially motivated by the now frequent claim that microbial community activities (“functions”) are more stable or ecologically resilient than are the taxonomic compositions of the assemblages carrying them out, a phenomenon demanding evolutionary explanation.
OK, we’ve listened to their song and dance. Before cheerily humming the tune, we’d better look at the lyrics. In this view, individuals don’t matter, nor do species. They’re just singers who come and go. The song’s the thing, not the things singing the song. This view might be called, ‘Survival of the Process.’ What happened to Godfrey-Smith’s warning about “too many parents”? Where did reproduction go? It went to a hyphenated word: “re-production.” The singers re-produce the song, without a requirement of sex or genes, and the song goes on.
To see how ITSNTS Thinking turns into a mystical idea, look at one example they take very seriously: the nitrogen cycle. Here is a “process” that benefits numerous communities of organisms. It is “stable” in the sense that even if populations come and go, individuals would surely “re-create” the nitrogen cycle, because it benefits them all. (We might say that the nitrogen ‘song’ keeps everyone humming the tune as individuals come and go in the evolutionary theater.) The beneficial process recruits individuals as needed to carry out their sub-function, and the process persists. In ITSNTS thinking, “the continuity of process ‘resides in the recursive representation of immortal pattern by ephemeral avatars (collectively implementing taxa)'” as D. Haig had suggested in 2014. Here’s how Doolittle applies ITSNTS to the evolution of the nitrogen cycle:
No individual of any species involved in that cycle performs its role self-sacrificially. Each has coevolved with other participants serving as its environment, or against a background of the products of these other participants. No alleles have been fixed just because they promote continuance of the nitrogen cycle as a cycle, for all that alleles that have been fixed may do that: the time scales are too long and there are “too many parents.” Thus, a completed nitrogen cycle … is only a “fortuitous benefit” of the coevolution of separate species, not an adaptation of some interspecies aggregate. Such properties might be seen as beneficial for life in the very long run, but have never been adaptations as traditionally defined by a history of differential reproduction within populations. Standard notions of ENS by differential reproduction, and associated concepts of adaptation of things, cannot apply.
Nevertheless, because each step of the nitrogen cycle in isolation can benefit a taxon that implements it, energetically or in the provision of metabolites, and because the cycle has long been in operation, many taxa (sometimes from all three domains and forming ecological “guilds”) have evolved that can and now do, collectively, perform it (Fig. 1).
So far, no comments have appeared about this proposal. If Doolittle and Inkpen hope that controversy will subside, most likely they have poured gasoline on the fire. Hard-line neo-Darwinists will scream that they have mystified natural selection. Richard Dawkins will complain that they have replaced selfish genes with selfish processes. And many may wonder about the origin of the processes, and how new beneficial processes could arise. To paraphrase DeVries, ITSNTS can explain the survival of the process, but not the arrival of the process.
Before anyone is tempted to drink Doolittle’s Kool-Aid, we want to point out that it has fatal flaws. If he can “Darwinize” the nitrogen cycle, and in the process eliminate traditional meanings of fitness, inheritance and reproduction, then natural selection has become disconnected from reality. It’s some mystical process out there that wants to “survive” by using real “things” as its pawns. Did you catch the phrase “immortal pattern by ephemeral avatars”? Sounds like Baal worship.
We might note with a snicker, too, that ITSNTS tries to look sweet and nice compared to “red in tooth and claw” – which means all those genocidal wars that Jerry Bergman documents in his book The Darwin Effect were for naught. In fact, if Doolittle is right, the perpetrators of those horrors were fighting against evolution! They failed to worship this Gaia-like providential deity that tries to keep the sweet song going. I hope you Darwinists are paying attention to what’s happening to your theory before the Kool-Aid sets in.
Needless to say, ITSNTS fails just as completely as all the other versions of natural selection at accounting for the origin of irreducibly complex systems. But perhaps the worst fatality in “ITSNTS Thinking” is that it accounts for too much. If all units of selection must be considered – genes, cells, organisms, species, and communities – singers in the grand old song, then why not add planets, solar systems, galaxies, and universes while they’re at it? And don’t forget the multiverse, too!
The most valuable service Doolittle and Inkpen have provided in this paper is not just the laughter at watching drunk old men singing “How dry I am” on stage. No, the biggest take-away from this paper is that natural selection remains a vacuous, ill-defined, vague, controversial, meaningless, illogical, mystical restatement of the Stuff Happens Law. Thank you, Dr. Doolittle. You have done much to advance our cause, “Time to Ditch Natural Selection” (3 October 2015).
Christians, creationists, ID advocates, please condemn this house of cards before it collapses. Evolutionists, run from it, too, so you won’t be caught in its downfall. Do something worthwhile with your science, like biomimetics. And historians, get out your keyboards. Natural selection will soon be known as the Worst Theory in the History of Science.