Scientific Censorship and Evolution

Wolfgang Wuster bss166 at clss1.bangor.ac.uk
Mon Apr 3 06:04:01 EST 1995


Just a biref reply to some of your comments:

On Thu, 23 Mar 1995, Richard Milton wrote:
> 
> Wolfgang Wuster wrote:-
> >On Wed, 22 Mar 1995, Richard Milton wrote:
> >
> >
> >Of course there are gaps! What do you expect from the fossil record and a 
> >sequence of fossils with millions of years between fossils??? 
> 
> Err. . .What? Millions of years _between_ fossils?  

I don't have any original references at hand, but from the diagram in
Futuyma(1986), I would guess that Hyracotherium and Orohippus are
separated by approx 7-8 million years. There seem to be similar gaps
between other rungs on the "horse evolution ladder". Any updates and
details welcome. 

> >Furthermore, nobody has ever claimed that these horses tell us anything 
> >about genetic mutation and natural selection. 
> 
> On the contrary, flawed examples of this sort are the
> central bulwarks of neo-Darwinism, yet as I pointed out they
> have nothing to do with the neo-Darwinist mechanism. 

Misuse of examples does not invalidate a theory. More to the point, what I
pointed out is exactly that they cannot tell us anything about
neo-Darwinist mechanisms, and therefore you cannot use them to criticise
neo-Darwinism as a theory (some of the practice is another matter). 

> > >They do tell us something 
> >about the evolutionary history of a lineage. The fact that the original 
> >interpretation was oversimplistic was unknown at the time. It is now 
> >known that the evolutionary history of the horse family was more complex, 
> >with reversals and parallel evolution in a number of lineages. However, 
> >this is not the same as calling a series of fossils "unconnected". They 
> >are all part of the evolutionary history of horses, which can be 
> >recognised by anyone with palaeontological training.
> 
> They can be recognised as a connected sequence only by
> someone who has no regard for the rules of evidence and is
> willing to fill gaps with imaginary fossils, as Simpson
> was and as you are evidently still prepared to do.
 
I am always amused by the trick of claiming a gap in the fossil record. 
Then, as soon as a "missing link" is found, the critic says: "Ah, but now 
you have two gaps!"
Seriously, the various forms involved can be recognised as horse-like by 
anyone who can tell a cat from a dog. They all form part of the horse 
clade. That many of them are part of different lineages within this clade 
does not suggest that they are not part of the horse family. What a more 
rigorous examiantion tells us is that the evolution of the horse was more 
complex than the early ladder showed, and some of the forms of the old 
ladder are not direct ancestors of the modern horses. This is certainly 
reflected in the textbooks I read.
>  
> >> The remarkable "Archaeopteryx" also seems at first glance to bear 
> >> out the neo-Darwinian concept of birds having evolved from small 
> >> reptiles (the candidate most favoured by neo-Darwinists is a 
> >> small agile dinosaur called a Coelosaur, and this is the 
> >> explanation offered by most text books and museums.)  Actually, 
> >> such a descent is impossible because coelosaurs, in common with 
> >> most other dinosaurs, did not posses collar bones while 
> >> "Archaeopteryx", like all birds, has a modified collar bone to 
> >> support its pectoral muscles. [4]   Again, how can an isolated 
> >> fossil, however remarkable, provide evidence of beneficial 
> >> mutation or natural selection?
>  
> >It is not claimed to provide evidence of beneficial mutation or natural 
> >selection, it does provide evidence of the history of the birds and their 
> >reptilian cousins. In archaeological terms, you are asking a fragment of 
> >Roman pottery to explain the full set of Roman business tax laws. 
> 
> Once again, this fossil _is_ used to bolster the
> neo-Darwinian mechanism even though as I pointed out is
> has no connection with that mechanism.  The point I was
> making is that it does not provide any evidence of kinship
> with Coelosaurs as many still wrongly claim (including
> people who should know better on this newsgroup). 
> 

Again, the bad use of examples does not invalidate the theory. I have
never seen anyone claim that Archaeopteryx is an example of beneficial
mutation or natural selection. It has been represented as what it is,
namely a creature with a mixture of advanced or primitive features, which
tells us something about the evoltuionary history of birds. It is
absolutely irrelevant to the debate about mechanisms, as it would be an
important fossil under any theory whioch proposes that all living things
are connected by an evolutionary history. The mechanisms are entirely
irrelevant to this. For all I care, it could have evolved in one
generation as a "hopeful monster" or anything else, it would still be an
important fossil showing an interesting mixture of derived and primitive
characters. It thus providea a nice piece of evidence for the occurrence
of evolution, but not for the mechanisms concerned. 
There have been some later speculative papers on the selection pressures 
which may have resulted in the evolution of flight in birds, but that is 
different from claiming that Archaopteryx is a "bulwark of neo-Darwinism".

> >> Even more baffling is the fact that radically different genetic 
> >> coding can give rise to animals that look outwardly very similar 
> >> and exhibit similar behaviour, while creatures that look and 
> >> behave completely differently can have much in common 
> >> genetically. 
> >
> >....which represents a nice example of how evolution by natural selection 
> >results in convergent adaptations for a given ecological niche. 
> 
> >
> >> There are, for instance, more than 3,000 species of 
> >> frogs, all of which look superficially the same. But there is a 
> >> greater variation of DNA between them than there is between the 
> >> bat and the blue whale.
> 
> >So?
> 
> So the neo-Darwinian concept that genetic structure is
> related to morphology is wrong. 
 
Nonsense. There is no serious neo-Darwinian concept which requires that a
change at the molecular level needs to be translated into morphological
change. Morphological change requires genetic change, but genetic change
does not necessarily result in morphological change. 

> >> Further, if neo-Darwinist evolutionary ideas of gradual genetic 
> >> change were true, then one would expect to find that simple 
> >> organisms have simple DNA and complex organisms have complex DNA.  
> >> In some cases, this is true. The simple nematode worm is a 
> >> favourite subject of laboratory study because its DNA contains a 
> >> mere 1,000 nucleotide bases. 
> >
> >As someone else has pointed out this figure is completely wrong. 1000 base 
> >pairs make on moderate-size proteins. Nematodes are simple, but they are 
> >not that simple.
> 
> I apoligise for this mistake which does not affect the
> point I was making.

It does say a lot about the quality of your information.
> 
> >> At the other end of the complexity 
> >> scale, humans have 23 chromosomes which in total contain 3,000 
> >> million nucleotide bases. 
> >> 
> >> Unfortunately, this promisingly Darwinian progression is 
> >> contradicted by many counter examples.  While human DNA is 
> >> contained in 23 pairs of chromosomes, the humble goldfish has 
> >> more than twice as many, at 47.  The even humbler garden snail -- 
> >> not much more than a glob of slime in a shell -- has 27 
> >  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^  a great malacologist in the making!
> >> chromosomes.  Some species of rose bush have 56 chromosomes.
> >
> >So? Since most DNA in any organism is junk anyway, and multiple copies of 
> >the same gene don't constitute greater complexity, your examples are 
> >completely irrelevant.
> 
> Let me be absolutely sure that I understand you
> correctly,  Wolfgang.  Are you here saying that genetic
> complexity is _not_ related to morphological complexity?
> And if not, what are you saying? 
> 
Let's make this simple:
Shakespeare is regarded as a great writer because of the richness, 
complexity and quality of prose he produced, not because of the total 
volume of his works. 
Britain's telephone directories contain a lot more words, but most people 
would not regard its authors as among history's greatest writers.

Having a lot of chromosomes and a lot of DNA in your nucleus is not 
complexity if most of the DNA either codes for nothing or is duplicate. 
How many proteins do salamanders or lilies produce? How many coding genes 
(excluding duplicates) are there in these organisms? That might be a better 
measure of complexity.

Many plants will produce tetraploid or even octaploid genomes, thus
doubling or quadrupling the size of their genome in one generation. They
are not measurably more complex in morphology. 

Genome size is simply not a measure of complexity.
> >
> >What was meant by that phrase is that *whichever characteristic confers a
> >reproductive advantage* will be selected for. A cheetah which runs faster
> >will catch more prey, and thus will have more energy available for
> >reproduction than a cheetah which is less successful at capturing prey.
> >There are an awful lot of ways of making a living out there, and hence
> >there are an awful lot of different animals doing just that. Physical
> >characteristics are, in evolutionary terms, a means to an end. 
> 
> I'm familiar with the conventional wisdom with all of its
> intuitive plausibility.  My objection is that this is
> merely supposition unsupported by evidence or experiment
> because it cannot be.  Show me the cheetah's sprinting
> gene: show me anything about this idea that isn't merely
> conjecture. 
> 
There is no such thing as a cheetah's "sprinting gene" - the fact that 
you bring up this kind of simplification tells a lot about your sources 
of information. There are sets of genes that affect the length of an 
animals legs, the flexibility of its back, and muscle development. Unless 
you wish to claim that animals spontaneously self-assemble without 
genetic control. 
> >
> >There may be some valid criticisms of Neo-Darwinism around. It may be true
> >that the reaction to such criticism is sometimes exaggerated and
> >oppressive. However, it should also be noted that the cry of "censorship" 
> >often rings out loudest when bad science is not published for the reason
> >that it is quite simply, err, bad science. 
> 
> The excuse of the self-appointed censor down the ages.
> 
As stated previously, you confuse censorship and quality control in a 
respected publication.
> >
> >The current article is based on total ignorance of basic evolutionary
> >principles. It would have been a great discredit to the THES had they
> >published this piece. 
>  
> I'll let them know they have such a devoted fan.  I'm sure
> they'll be delighted. 
> 
Actually, I am not much of a fan of the THES, since they seriously 
considered publishing this in the first place. As someone has already 
pointed out, it is rather sad that Dawkins' intervention was needed to 
point out to the THES that this article is not worth publishing.

Wolfgang Wuster

School of Biological Sciences, University of Wales, Bangor.



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