by Thomas Riggins
The philosopher Jerry Fodor is rightfully upset with some of the nonsense coming out of Academia disguised as science and dressed up in arguments purportedly derived from Darwin’s theory of evolution. Lots of nonsense put forth under the guise of “evolutionary psychology” is a good example. Here complex behavioral patterns of humans today are explained as inherited traits from our animal past or traits that we evolved when we were hunter gathers on the African savannah.
As an example, capitalism, for instance, is often justified, or explained, as a part of “human nature” [as is war, male supremacy, and “innate” racial differences in intelligence] inherited from our remote past. These claims, among others, have led Dr. Fodor to question Darwin’s theory that the mechanism driving evolution is “natural selection”.
This article will look at his arguments as presented in “Why Pigs Don’t Have Wings” from the 18 October 2007 issue of The London Review of Books. I will try to establish that his arguments against natural selection are not convincing and are based on a mechanical interpretation of Darwin that is a characteristic of contemporary Western thought. That when Darwin is read dialectically, as he was by Marx and Engels (Cf. Engels’ Dialectics of Nature) the objections to natural selection as the main motor of evolutionary change evaporate.
Fodor tells has that natural selection “purports to characterize the mechanism not just of the formation of species, but of all evolutionary changes in the innate properties of organisms.” An organism’s phenotype [“the inventory of its heritable traits, including, notably, its heritable mental traits “ is an adaptation to its environment.
The rub here is “mental traits.” Physical traits can be mapped on the genome and have some basis in material reality. This is much harder to do with so called mental traits. Most all of the current nonsense about evolutionary explanations of human behavior based on inherited mental traits is the result of idle speculation concerning hypothetical genes that could, maybe, be responsible for the behaviors in question. At most, however, we can only discuss the capacities that humans have inherited. The vast majority of specific behaviors are better explained by external causes, mostly of cultural and historical origin, which have nothing to do with an organism's phenotype. Nor did Darwin, I think, suggest otherwise.
Adaptation works this way. Organisms are living in an environment and competing for food and reproductive success. Some type of genetic mutation comes along [a cosmic ray zaps one of its genes say] that gives the organism a slight edge in finding a mate and reproducing. More babies carrying the new gene show up in the next generation, etc (providing the gene is inheritable). Eventually all the organisms have the new characteristic: a new species. This is very simple, but you get the idea. It doesn’t have to be a new species. It could be a gene for eye color and so you just have variation within a species, for example.
Now Fodor says that Darwin’s theory has two components. The sequence of changing phenotypes, we can see the connection phenotypically, genetically, that puts baboons in our family tree. No doubt about that. But how did that happen? It is the answer “by natural selection” that he wants to question. No, he is not a creationist. He is looking for a purely scientific answer, not mysticism, to replace natural selection because he sees flaws in that explanation. Flaws that I will attempt to show do not exist.
Fodor reports that there is something that “ails” us a species living in the contemporary world. Marxists agree and attribute it to our economic arrangements-- i.e., capitalism and its logical consequent of human exploitation for profit which leads to imperialism and war. Fodor says the Darwinists explain the problem by saying we inherited a mind adapted for life 30,000 years ago and is unequipped to live in the complex world of today. He will attack natural selection because he thinks this Darwinist answer is wrong.
But this is not Darwin’s answer at all. It is modern misinterpretation of Darwin that has arisen as a refection on the modern world in societies which, due to the class nature of science and education, do not fundamentally challenge the prevailing order [TINA] and thus reject ab initio a Marxist reading of evolution.
What ails humanity is for Darwinists, according to Fodor, "that the kind of mind we have is an anachronism; it was selected for by an ecology that no longer exists." This being the case, Fodor says, "if the theory of natural selection turned out not to be true, that would cut the ground from under the Darwinist diagnosis of our malaise."
Fodor is right about that. But it is wrong to think that natural selection has provided us with an anachronistic "mind". The so called Darwinists who argue that way are very far from Darwin or any scientific understanding of the human brain.
What natural selection has provided us with is a brain with the capacity to adapt the organism to many different social and cultural climates. It is no more the product of events 30,000 years ago on savannas then it is of modern industrial societies. As far as anyone can say it also has the capacities to adapt to future social and cultural conditions as yet unimaginable. There is no need to reject natural selection "to cut the ground from under the Darwinist diagnosis" because the characterization given by Fodor, while maintained by many social "scientists" and some shallow schools of "evolutionary psychology", is a totally unscientific version of "Darwinism."
But suppose as a matter of fact natural selection is still incorrect. Fodor says it has two problems that might undermine it: one is conceptual, the other is empirical ("more or less.") Let's look at these two.
I must admit, I don't really see the conceptual problem. Here is what Fodor says it is. Natural selection can be seen as holding that "environments select creatures for their fitness; or you can say that environments select traits for their fitness." But I wouldn't say that environments "select" anything. Organisms ("creatures") are born into environments and their ability to survive and reproduce depends on the traits they have. If a frog has a mutation giving it three legs it may not live to reproduce. If it has a mutation making it resistant to a virus that infects and kills frogs that trait may allow it to reproduce better than other frogs.
Is not it confusing to talk of "forces of selection," as does Fodor.? "These forces must select individual creatures on the one hand, but on the other they must select traits" since it is phenotypes ("bundles of heritable traits") "whose evolution selection theory purports to explain."
This whole discussion of a "conceptual problem", of a mechanical contradiction invalidating natural selection, is itself a conceptual problem [a category mistake], or better a terminological one. Let's get rid of needless metaphysical entities such as "environments making selections". and "forces." Next, consider that "phenotypes" are not real existing separate entities. They are intellectual abstractions that we as scientists or philosophers use to describe the workings of our theoretical explanations for what we find in nature. Only the organisms exist.
I think, therefore, that the conceptual problem is bogus. I will therefore skip over the rest of the conceptual discussion, which concerns itself with Venetian, architecture, Darwin's analogy between selective breeding techniques and natural selection (and Adam Gopnik's New Yorker article about the same), and associated problems with metaphors such as God and Mother Nature.
Let us now turn to the empirical problem. It is not so much a problem as an "issue" for Fodor. He starts by saying that as a matter of fact some new empirical explanations for evolution are being proposed that do not base the mechanism of change on natural selection. He says he can't discuss all of these new ideas but will give us a "feel" for two of them.
First, Fodor points out that "phenotypes don't occur at random"-- i.e., for me that means we don't group organisms together arbitrarily. We group them together because of the similarity we see, or think we see, between organisms. Because, for example, all the animals we see in what we call the cat family are more similar to each other in ways than they are to organisms we classify as members of the dog family we conclude they have an evolutionary connection and their membership in the same family is non-random.
Fodor says the nonrandomness of the phenotypes is due to the nonrandomness of the environment. He tells us the "theory of natural selection in a nutshell" is if the nonrandomness we see between phenotypes [i.e., organisms] and their environments isn't due to God, "PERHAPS [my emphasis] it is a reflection of the orderliness of the environment in which the phenotypes [i.e., the organisms-tr] evolved." In other words a fossil fish may indicate that there was a watery environment, and a fossil bird would suggest an environment conducive to flight.
But, Fodor says, "this is not the only possibility." "External environments are structured in all sorts of ways, but so too, are the insides of the creatures that inhabit them" [natural selection may have something to do with this-- tr]." There is another possibility, an alternative to the view that phenotypes [our mental constructions based on knowledge of real organisms-tr] reflect the environments they evolve in, "namely that they carry implicit information about the endogenous structure of the creatures whose phenotypes they are."
"Whose" is a possessive and we should remember that it is organisms that "possess" phenotypes not the other way around. But let us grant "phenotypes" the same ontological status as organisms. Fodor has not really put forward an alternative view. This view, by the way he refers to as "Evo-Devo" (evolutionary-developmental theory).
Darwin's theory of natural selection regarding an organism's response to the environment, and evo-devo, the organism's internal structure are two sides of the same coin. They are not alternative explanations, but, as Marxist dialectics would have it, they are a unity in difference.
Gene theory developed after Darwin. So now we know that the mechanism by which natural selection's response to the environment, takes place is by changes in the genetic make up of the organism. How, or what, causes the genes to change is another question. Fodor has a reduction to biochemistry down to quantum mechanics ("for all I know."
This is pointless as far as the theory of natural selection is concerned. The organism either adapts to its environment and successfully reproduces itself or it becomes extinct. So when Fodor says, it is "an entirely empirical question to what extent exogenous variables are what shape phenotypes; and it's entirely possible that adaptationism [natural selection] is the wrong answer" he is way off base. The inner and the outer (genome and environment) are two aspects of the same thing-- the living organism.
Now Fodor asks a very strange question. Granted that when we ask Darwin why two phenotypes (organisms) are similar this can be explained by common ancestry. But what if you ask "why is it that some phenotypes don't occur, an adaptationist explanation often sounds somewhere between implausible and preposterous." If you ask, that is, why some sort of organism did NOT evolve natural selection can't give a satisfying answer. How would natural selection explain why there are no pigs with wings?
Fodor says they lack wings "because there is no place on pigs to put them." You would have to "redesign pigs radically" to have them have wings. Natural selection won't let you go back "and retrofit feathers" [of course mammals don't need feathers to fly]. For Fodor, this means there are constraints "on what phenotypes can evolve that aren't explained by natural selection." This is just so wrong.
Natural selection explains perfectly well why pigs don't have wings. Again it is pigs, not "phenotypes" that lack genes for wings. Lets look at the real question. Why do bats have wings. Bats and pigs are both mammals and they at one time shared (with many other kinds of animals) a common ancestor. The common ancestor to bats and pigs, et al, was a much more generalized animal to any of its many descendants.
Natural selection says that mutations with positive adaptive (reproductive) values that happened to the common ancestor and its offspring gave rise to all of its descendants different mutations leading to different adaptations to the many possible environments which these animals could live in. Bats have wings and pig's don't because the organisms that eventually turned into bats and pigs had genetic changes that allowed them to exploit different parts of our common earthly environment.
Fodor's question doesn't really make sense. Why don't pigs have wings is the same as asking why didn't pigs become bats. Or why are there pigs? Natural selection also answers the related question as to why horses don't have a single horn on their foreheads.
Fodor calls this kind of speculation "channeling." But all the restraints that have been placed on pigs to prevent them from flying have been channeled by the operations of natural selection. How would natural selection take place in order to result in a flying mammal? It is to the bat genome, not the pig genome that we should look. So much, I think, for the "feel" of the first alternative to natural selection. It really ends up supporting natural selection.
Let us look at Fodor's second alternative and get a "feel" for it as well. Fodor thinks that evolutionary traits that come about by natural selection are supposed to enhance fitness. So if a suite of traits shows up in the evolutionary record that doesn't enhance fitness, something must be wrong with the theory of natural selection.
He discusses a forty year experiment to breed tameness into silver foxes. The experiment was successful and after thirty generations of inbreeding a strain of very tame foxes was the result. But besides tameness the foxes had many other new traits as well-- floppy ears, short curly tails, short legs. etc.
He thinks this is evidence against adaptationism (natural selection). He says, "the ancillary phenotypic effects of selection for tameness seem to be perfectly arbitrary. In particular, they apparently aren't adaptations; there isn't any teleological explanation-- any explanation in terms of fitness-- as to why domesticated animals tend to have floppy ears [cats?]."
In the first place these foxes did not come about by natural selection, but by deliberate breeding. All tame foxes were bred by human design so any "ancillary" traits were bred also (who knows if they would have survived by unaided natural selective processes.
In the second place, natural selection's main point is that positive traits that further reproductive success will tend to be propagated, negative traits that hinder reproductive traits will tend to be eliminated, and neutral traits may or may not be eliminated. A neutral trait like floppy ears, associated with a positive trait like tameness (in the experiment) will get a free ride as a neutral trait even without a positive adaptive function.
There is nothing strange or mysterious about this. It is standard operating procedure in Darwin's theory of natural selection. Although Fodor definitely would not agree, the floppy ears and other reproductively neutral traits are flukes.
I think nothing in his article poses either conceptual or empirical problems for the theory of evolution by means of natural selection as proposed by Darwin. As far as evolutionary psychologists and sociobiologists are concerned, let them come up with specific genes located in the human genome for the characteristics they claim humans exhibit as a result of living in a primitive savanna like environment in the prehistoric origins of the species. The springs of human behavior are not frozen in the past.
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