Poison-resistant tomcods and the meaning of ‘evolution’
Published: 19 May 2011 (GMT+10)
Joanie Côté, Wikipedia.org
The Atlantic tomcod only benefits from its information-losing mutation in the heavily polluted Hudson River.
In response to the article on the mutated tomcod fish in the polluted Hudson River, evolution-defender Steven L. wrote in claiming that it contained “blatant mistakes” and gave substantial detail and detailed reasons. We first publish his email intact, then again with a point by point interspersed response by the article author, Dr Carl Wieland of CMI-Australia.
Your article on the evolution of the Tomcod possesses a few blatant mistakes.First of all, it assumes that mutations are some form of “damage”. That is not the case. Mutations are a fact of life (and are necessary for evolution to occur), and the vast majority of mutations are strictly neutral—that is, they are not expressed, or their expression has no effect on the life of the organism.Secondly, the article posits that information gain is a necessity of evolution. This is false—evolution is simply change, whether it be through the addition, deletion, or alteration of base pairs. While we tend to see a net gain of information as demonstrated by the increasing complexity of the fossil record over time, it is not a requirement.Third, the article references the deletion of the base pairs in the tomcod as a sort of “downhill damage”, but it is not taking the environment in to account with this assessment. In their current environment, the mutation is anything but. The overall cost/benefit analysis of a mutation has to be made within the context of the environment in which it occurs.Fourth, the article states as fact that the mutation happened in one generation. This is not necessarily the case, but the author has assumed it to be true and has stated as such without any evidence to back his position. Because the mutation also exists occasionally in the non-poisoned populations elsewhere, it suggests that the mutation already existed in the overall population of the animal. It is a similar situation to the 1952 Lederberg experiment. Further still, the continued existence of the mutation in roughly 5% of the population from uncontaminated waters shows that the relative cost of the mutation isn’t so large as to make it a major hindrance to reproductive success. Like any other healthy, genetically diverse population, we see a variety of different genes existing in greater or lesser numbers within the population.In summary, you should strive to have a bit more accuracy in your articles.
Carl Wieland responds:
Thank you for your email.
Your article on the evolution of the Tomcod possesses a few blatant mistakes.
Well, it’s important to know of any mistakes, even in a brief item responding to a news article meant for the layperson; but let’s see how accurate this confident assertion of yours is. I would ask you to try to lay aside your presuppositions and [try] thinking the matter through carefully for yourself, because there is a lot at stake. My responses are interspersed with your email below.
First though, note that the article was not on the ‘evolution’ of the tomcod, but on how it adapted to pollution. When people hear the word “evolution”, they assume it means the same sort of change as would, given time, turn protozoa into people, etc. The article was about demonstrating that this is an inappropriate description of what happened.
First of all, it assumes that mutations are some form of “damage”. That is not the case.
The article actually used the word “damage” in the specific context of those mutations that cause antibiotic resistance, and gave one such example of exactly that—damage to a functioning mechanism. It then indicated that mutations mostly damage existing structures. So that is not the same as your representation of the article’s claims.
Mutations are a fact of life
Agreed. In this fallen world, such genetic copying mistake are exactly that—mistakes. What do we observe in the process of heredity in living things, if not a highly complex mechanism which functions to produce a letter-by-letter copy of the genetic information (DNA). Even those who deny purpose (teleology) in living things overall would have to agree that this machinery’s role is to produce such a copy. It even incorporates error-correcting and proof-reading machinery. Most mutations occur when, despite this, there is a deviation from an exact copy. Not surprisingly, then, the biological machinery that is coded for on the DNA that undergoes a mutation is generally not likely to result in an improvement, but the opposite—for the same reason that a random change in a software code that has a specific function is very, very unlikely to generate an improvement in that function, but more likely the opposite. So to say that mutations will mostly ‘damage’ things makes sense even at first glance—but see more shortly. The argument is one from probability; there are many more ways to break things than make them.
(and are necessary for evolution to occur),
You are right that ultimately mutations are the ‘only game in town’ for evolutionists as a theoretical source for the ‘raw material’ for ‘nature’ to ‘select from’. Natural selection (NS) in and of itself culls genes, gets rid of information. See Muddy waters: clarifying the confusion over natural selection. If copying were perfect, all the selection in the world could never generate any real evolutionary novelties, being restricted to differing combinations of what is already there. But the big question then is: are mutations capable of doing what they are supposed to have done over billions of years, i.e. generated all the information needed for all the biological machinery in all organisms on Earth? For those whose kneejerk, even socially conditioned, answer is ‘yes’, it’s interesting that the examples in textbooks of ‘evolution happening’ are either examples where there is not even demonstrable mutation involved (i.e. the selection which led to adaptation was from existing variety in the population, and involved a loss of genes or thinning of the gene pool). Or else, where a mutation was involved, the mutation was a definite loss or degradation of information. For example, wingless beetles on windy islands.
and the vast majority of mutations are strictly neutral—that is, they are not expressed, or their expression has no effect on the life of the organism.
In fact, it is nowadays more accurate to say that the vast majority of mutations are near-neutral; i.e. they are deleterious, but the effect is so small that it is to all intents and purposes just as you put it, that it has no discernible external effect and thus is transparent to selection (which simply means that NS has no way of eliminating these near-neutral mutations). This is actually a severe detriment to evolutionary theory, as former Cornell University (and still courtesy) professor, and genetic engineering pioneer Dr John Sanford has shown in his book Genetic Entropy and the Mystery of the Genome (a good introduction to the subject is the DVD of an excellent presentation he gave on the subject to a conference involving both lay and professional folk.) To explain: the latest figures show that these near-neutral mutations are accumulating so rapidly that our human genome is actually facing a very serious decline, a situation worsening with every generation. Their near-neutrality is actually a detriment, precisely because of what was stated above, namely that NS can’t get rid of them individually fast enough. But their combined, cumulative effect is very deleterious, since they are so numerous. See this interview with Sanford for a foretaste of what the other items go into in more detail. It was this that helped bring Sanford around from his former position as an evolutionist to being not only a creationist, but a convinced believer in recent creation. The human genome simply can’t have been around for more than a few thousands of years at most, in order to have avoided what is known as ‘error catastrophe’. This reality has been backed up by sophisticated supercomputer modelling of the mutation-selection process (see http://mendelsaccountant.info/).
Secondly, the article posits that information gain is a necessity of evolution. This is false—evolution is simply change, whether it be through the addition, deletion, or alteration of base pairs. While we tend to see a net gain of information as demonstrated by the increasing complexity of the fossil record over time, it is not a requirement.
With respect, the last sentence of the above paragraph reveals the flaw in the reasoning of the entire paragraph. If we define evolution as ‘genetic change’, then that change can be in any direction. But that would be a self-serving, question-begging definition, since a Creation-Fall model would also expect ‘genetic change’, but in a net downhill direction. To put it very simply—an evolution model would expect change happening in all directions, so downhill change per se does not falsify the idea of evolution by any means, nor was that claimed in the article. However, we need to remember that I’m defining ‘evolution’ in the way most people understand it—and the way Darwin proposed, not mere ‘genetic change’, but, as the article stated, a process that has allegedly turned microbes into magnolias, mosquitoes and microbiologists. So to demonstrate that a particular proposed mechanism (neo-Darwinism) is able to produce genetic change adds no credibility to that mechanism [as a driver of evolution, and a demonstration of ‘evolution happening’] if it seems to mostly, if not exclusively, lead to ‘downhill’ change.
To focus once again on your last sentence—a “net gain of information” is not what “we tend to see”. It is, however, what you must believe has occurred, since you believe that a microbe with ~0.5 million base pairs on its DNA did eventually turn into a microbiologist with 3,000 million base pairs. We can also think of the traits that humans have that microbes don’t: muscle, skeleton, blood vessels, nerves, skin, hair, etc. These traits require new specifications to be added to the DNA (a minimalist microbe has a few hundred proteins, but humans can make over 100,000 different ones). So by definition, there must have been a huge “net gain of information”. Which means that gain of information has to be a major part of the alleged evolutionary process (especially since it has to overcome the overwhelming tendency of mutations to destroy the information). A businessman making lots of $10 sales cannot make a net profit on all of them combined unless most of them make an actual profit. Do you see the point? By you conceding, in effect, that a “net gain” had to have happened to turn microbes into mudskippers, you are reinforcing the fact that there needs to have been a lot of actual gain by mutation. And in fact, if we saw lots of information-gaining mutations in the process of building new structures and functions all around us, it would be legitimate for an evolutionist to take this as a positive and strong support for his proposal. However, if virtually all known mutations associated with adaptive change are in this opposite direction, then wouldn’t you agree that it is misleading to use such adaptive change as an example of ‘evolution happening’? That was the point of the Tomcod article.
Indeed, your definition of evolution as merely ‘change’ can be shown to be an extraordinarily lame one, since it makes all and any genetic change ‘evolution’. So if every type of genetic change in the world were to be such as to lead to extinction, by your definition that would still be ‘evolution’.
Third, the article references the deletion of the base pairs in the tomcod as a sort of “downhill damage”, but it is not taking the environment in to account with this assessment.
First, a description like ‘downhill damage’ is never going to be a rigorous statement, but it makes a valid point nonetheless, and second, the article most definitely took the environment into account. To clarify: as our article on wingless beetles points out, a defect can have a survival advantage in a particular environment. A beetle having a mutation that in its offspring destroys the ability to produce normal wings is better able to survive and have offspring on a windy island, as it is less likely to be blown into the sea and drown. So in time, all those beetles on that island are likely to be of the wingless variety. But this shows us a complex information-transfer and construction system (the machinery by which the genetic information in beetles gives rise to wings, with their specific function able to be defined in engineering terms) and how this system is then subject to corruption, loss of function, etc. This can hardly of itself give any clues as to how such a process of random change could have led to that complex system in the first place. Sheep with crippled legs might be better able to survive because they are less likely to jump over a fence into the jaws of a hungry dingo, so in that environment, once again, a defect is a survival advantage, but is still a clear defect. The neo-Darwinian mechanism could gain some credibility if Darwinists could point to hundreds of mutations (among the vast numbers occurring constantly) that can be seen to be building structures, adding functional complexity, etc. (in a complex world, one would expect the occasional tiny bit of information to arise by chance, and that may have occurred with bacterial ability to digest nylon, though note the careful analysis in our article on this). But that is simply not what happens in the real world.
In their current environment, the mutation is anything but. The overall cost/benefit analysis of a mutation has to be made within the context of the environment in which it occurs.
Of course. That’s simple population genetics, which is quite independent of the truth or otherwise of the neo-Darwinian postulate. The issue still remains this:
- there has to have been a massive net gain of information if ‘evolution’ has actually happened in history.
- Such a net gain requires substantial amounts of informationally ‘uphill’ change, no matter how much downwards or sideways movement may have occurred along the way.
- It is the extreme paucity of any informationally uphill changes by mutation (virtual absence), which is actually expected on probabilistic grounds, that justifies extreme scepticism about neo-Darwinism as a credible mechanism for any ‘evolution’, and to call downhill change “evolution” is only convincing if there is already a prior belief that evolution has happened.
Fourth, the article states as fact that the mutation happened in one generation. This is not necessarily the case, but the author has assumed it to be true and has stated as such without any evidence to back his position.
I find it hard to see why it’s not obvious that mutation, by definition, always happens in one generation. It may take time to spread through the population, but a mutation is a one-time event (though it can sometimes occur more than once, i.e. the same mistake can just happen to be repeated in another individual). The relevant sentence in the article started with “Mutation happens in one generation,” which by both the absence of either ‘the’ or ‘this’ in front of it, as well as by the use of the present continuous tense should, I would have thought, made it clear that this was a statement about mutation in general, and not just about this mutation. It then went on to talk about the expected rapidity of spread of “the mutated gene” after that initial event (obviously now referring to the tomcod one in question, i.e. in this “poison-rich environment”). It specifically said that this took “just a few decades”. Since this is obviously a lot more than one generation, it’s obvious that your comment here substantially misrepresents the article. I presume you have simply misunderstood.
Because the mutation also exists occasionally in the non-poisoned populations elsewhere, it suggests that the mutation already existed in the overall population of the animal. It is a similar situation to the 1952 Lederberg experiment.
I have no problem with the possibility that the same mutation may exist in non-poison-exposed populations, though note that in the case of antibiotic resistance to penicillin studied by Lederberg in his classic experiment, it was not necessarily the case that the resistance that was already in the population had itself arisen by mutation, i.e. the experiment itself did not demonstrate that. But my question to you is: Why would that affect any point in the article, and in this reply, in the slightest? I could have just as easily said (and maybe should have, for clarity) that the mutation arose at some point in one generation and then took only a few decades to spread in that poison-rich environment. But see my next point for what may be a better explanation for the low level of the mutation “in the non-poisoned populations elsewhere”.
Further still, the continued existence of the mutation in roughly 5% of the population from uncontaminated waters shows that the relative cost of the mutation isn’t so large as to make it a major hindrance to reproductive success.
That’s possible, but given the comments about the disadvantages to the organism that were reported from this mutation, it is not likely. A major point you seem to have overlooked when referring to the 5% from my article is that these waters were “nearby”. So that allows for a ‘supply’ of mutated fish to these less contaminated waters (which may in any case have previously been contaminated, but cleaned up relatively recently, for all I know) from the Hudson where the gene is kept at a high frequency. Thus, as the Hudson contamination presumably declines from legislative efforts, etc., one would expect a decline of the gene’s frequency not only in the Hudson, but also to much lower levels than the current 5% in nearby waters. A gene with such effects as mentioned in the article would be expected to approach zero frequency in due course in waters with no such poisons and no nearby ‘feeder’ source of this mutation.
Like any other healthy, genetically diverse population, we see a variety of different genes existing in greater or lesser numbers within the population.
This benign-sounding description makes it sounds as if these fish are ‘as healthy as any other’. It ignores the fact that the researchers themselves concede that the fish carrying this mutation are not as ‘healthy’ as those without it—to use their words again, these fish have “suffered in other ways”.
In summary, you should strive to have a bit more accuracy in your articles.
We strive for accuracy at all times, and are grateful when people point out perceived inaccuracies, as sometimes they are correct, of course. It seems though that in this case a commitment to evolution as ‘established fact’ may have detracted from what I think might otherwise have been a careful reading of the article.
I hope that you will understand a little more where the creationist argument is coming from via this exchange, including following the links provided (and those provided on those linked articles).
Thank you for the opportunity to clarify.