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Feedback 2011
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.
Steven wrote:
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.
You wrote:
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.
When people hear the word ‘evolution’, they assume it means the same sort of change as would, given time, turn protozoa into people.
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.
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.
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.
Sincerely,
Carl W.
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