Why the Peppered Moth Remains an Icon of Evolution

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The journalist Judith Hooper has recently leveled unfounded charges of fraud against Bernard Kettlewell, the distinguished naturalist who demonstrated natural selection in the peppered moth in Britain. My colleague Ian Musgrave and I recently analyzed Kettlwell’s data and Hooper’s charges, and concluded that the charges are wholly without merit. What follows are lightly edited excerpts from our paper in Skeptical Inquirer.

Kettlewell’s experiments. Beginning in the mid-1800’s, successive generations of peppered moths (Biston betularia) in Britain gradually darkened in response to the air pollution in the industrialized parts of the country. Kettlewell showed that the dark, or melanic, form of the moth predominated primarily because of predation by birds. He did not think that predation was the only cause of industrial melanism and in fact speculated as to the relative strengths of other causes. Briefly, he performed a number of experiments:

1. Release-recapture experiments

2. Direct observation and filming

3. Ranking of camouflage

4. Correlation of geographical distributions with industrialization

In our paper, we discussed only the release-recapture experiments reported in 1955, because these are the experiments that are under fire and because (unlike Kettlewell’s critics) we could bring quantitative tools to bear.

Kettlewell reported releasing and recapturing moths during an 11-day period in 1953. Hooper has noted that the number of recaptures increased sharply on 1 July, the same day that Kettlewell’s mentor, E. B. Ford, sent Kettlewell a letter. Ford’s letter commiserated with Kettlewell for the low recapture rates but suggested that the data would be worthwhile anyway. Hooper charges that Kettlewell began to falsify his data after receiving the letter, which she perceives as threatening.

Two facts, however, militate strongly against a finding of coercion. First, Kettlewell finished collecting data in the wee hours of the morning of 1 July and therefore could not have received the letter before collecting his data on 1 July. Second, he markedly increased the number of moths he released on 30 June, the day before the letter was mailed, not 1 July. Additionally, as Hooper admits, he continued to release a high number of moths after 30 June. Not surprisingly, he also recaptured more moths: more moths released, more recaptured.

Why did Kettlewell release more moths beginning on 30 June? Because the moths were just hatching from their cocoons, and he had no control over their number.

Statistical analysis. Still, his recapture rate, as well as the absolute number of moths recaptured, increased from 12 % over the first 3 days of his experiment to 26 % over the last 3 days. So we decided to get Kettlewell’s data and develop a mathematical model. We used the model to perform an uncertainty analysis. The results of that analysis, explained in our SI paper, show that the model conforms to Kettlewell’s daily recapture rates well within expected experimental uncertainty.

Additionally, we hypothesized that the brightness and duration of exposure to moonlight may have influenced Kettlwell’s recapture rates. When we included moonlight in our analysis, we found that the model conformed slightly better to the recapture rates.

Finally, we used a goodness-of-fit test (a chi-squared test) to compare the model’s predictions with the observed data and found that the model and the data differ insignificantly.

Kettlewell’s data are simply accounted for by the unsurprising fact that you can recapture more moths when you release more – that and normal experimental variation. We have no need of Hooper’s perverse, ad hoc hypothesis of fraud.

Conclusion. Hooper’s claims are moonshine; they are based on a lack of understanding of Kettlewell’s experiments in particular and experimental science in general. Hooper evidently did not realize that the change in recapture numbers began before Kettlewell could have read the letter that supposedly triggered this change, let alone consider the most likely cause of the changes she saw, exposure to moonlight. Hooper should have performed a careful analysis before she presumptuously insinuated fraud.

Kettlewell’s conclusion – that predation by birds was a major factor in promoting industrial melanism – was based on at least 4 lines of inquiry. It did not rely on the release-recapture experiments alone. It is also supported by at least 30 studies of different moth species that developed melanic forms, as well as independent replications of Kettlewell’s landmark experiments. In other words, an enormous body of evidence supports Kettlewell’s conclusion. Even if Kettlewell’s release-recapture experiments were ruled out, we would still be forced to conclude that industrial melanism is the result of natural selection due to bird predation, possibly among other causes.

Thus, there is no foundation for assuming that Kettlewell’s data were manipulated. The variations in his data are no more than the uncertainties associated with sampling and other factors, possibly including exposure to the moon. It is an irresponsible leap to accuse a distinguished naturalist of fraud on the basis of a single letter and a wholly imperfect, offhand analysis of his data. The peppered moth properly remains a valid paradigm – no, an icon – of evolution.

Acknowledgements. Thanks to Ian Musgrave, Pete Dunkelberg, and Bruce Grant for helping me understand the uncertainties of field work in biology, and to Laurence Cook and Nicholas Matzke for reviewing the SI paper.

References.

Cook, L. M. (2000). “Changing Views on Melanic Moths,” Biological Journal of the Linnean Society 69: 431-441.

Cook, Laurence M. (2003). “The Rise and Fall of the Carbonaria Form of the Peppered Moth,” [i]The Quarterly Review of Biology 78(4): 1-19.

Coyne, Jerry (2002). “Evolution under Pressure,” Nature 418: 20-21.

Grant, Bruce (1999). “Fine Tuning the Peppered Moth,” Evolution 53: 980-984.

Grant, Bruce (2002). “Sour Grapes of Wrath,” Science 297: 940-941.

Hooper, Judith (2002). Of Moths and Men: An Evolutionary Tale, New York: W.W. Norton.

Kettlewell, H. B. D. (1955). “Selection Experiments on Industrial Melanism in the Lepidoptera,” Heredity 9: 323-342.

Kettlewell, H. B. D. (1956). “Further Selection Experiments on Industrial Melanism in the Lepidoptera,” Heredity 10 (Part 3): 287-301.

Majerus, M. E. N. (1998). Melanism: Evolution in Action, Oxford: Oxford University Press, Chapter 6.

Majerus, M. E. N. (2002). Moths, London: HarperCollins, Chapter 9.

Majerus, M. E. N, Brunton, C. F. A. and Stalker, J. (2000). “A Bird’s Eye View of the Peppered Moth,”Journal of Evolutionary Biology, 13:155-159.

Mallet, Jim (2004). “The Peppered Moth: A Black and White Story after All,” Genetics Society News 50: 34-38. Available at http://abacus.gene.ucl.ac.uk/jim/pa[…]ppered04.pdf.

Musgrave, Ian (2005). “Paint It Black: The Peppered Moth Story,” in Icons of Evolution, Society for the Study of Evolution Education Committee, to be published.

Shapiro, Arthur M. (2002). “Paint It Black,” Evolution 56: 1885-1886.

Young, Matt, and Ian Musgrave (2005). “Moonshine: Why the Peppered Moth remains an Icon of Evolution,” Skeptical Inquirer, March-April, pp. 23-28, http://www.csicop.org/si/ (not available on the Web as of this writing).

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58 Comments

Whether Kettlewell was fraudulent or not, and I don’t think he was, is beside the point. Kettlewell himself, when congratulated on finally demonstrating Natural Selection, responded by saying that his observations had nothing to do with evolution, only with the selection for one or a few genes. Natural selection never had anything to do with evolution anyway as its sole role has been to maintain, as long as possible, the status quo. That is all its does today and that it all it has ever done. To claim otherwise is pure mysticism but then that is all that Darwinism is anyway, blind faith in the proposition that everything in the living world is and was an accident. Don’t you ever believe it. I sure don’t as is pretty obvious by now.

John A. Davison

Natural selection does not maintain the status quo.

When was the last time you saw a do-do or giant land sloth?

Things become extinct. That leaves a niche. That niche becomes filled. Things evolve to fill it.

Evilgeniusabroad

Actually natural selection promotes extinction by being anti-evolutionary which it all that ever did and continues to do today.

As you say things, become extinct and that certainly does leave a niche. Those niches are probably being filled allright but not be newly evolved forms. They are being filled by creatures who have not yet become extinct: simple as that.

Here is a task for you. Pick a species known to have recently become extinct and show me the organism evolving to fill that niche. There are literally thousands of such organisms from which you can choose. Report back in a week or so. Good luck. No prokaryotes please. They are boring.

Your last sentence is pure Darwinian mysticism, totally devoid of reality.

Evolution is a thing of the past, just as Grasse has so eloquently indicated. To continue to blindly insist that evolution is a continuing process is completely without justification.

John A. Davison, grossly unfair, completely off his rocker (just ask Scott Paige), but still unafraid to confront the big bad Darwinian wolf wherever it continues to rear its silly drooling head.

Yes John A Davison. Selection of one or two genes. Obviously no-one believes that other genes also have variant alleles. Obviously, when previously unseen variant alleles are noted to appear, they could not actually be common or natural. Obviously, since mutations are somewhat random and a given population might not exceed the number of bases in the genome, mutations that have not previously occurred could not happen. Obviously, absolutely none of these could alter favourably any aspect of the organism (increasing rate of oxidation of a novel toxin for instance), even if previously untested in all environments. Obviously the environment does not vary. Obviously, in differing environments, selection would favour variants optimal for the original environment. Obviously, organisms never move beyond their natal environment, nor are they moved.

Only lunatics would believe that genes are the single greatest influence on bodily development and growth, that they vary, that the variations are heritable, that such variations are each individually and collectively subject to selection and that such selection might result in considerably different combinations of alleles in differing circumstances. Only an utter twit would acknowledge that new gene loci are produced by various types of mutation events, or even that the products or partial products of such genes have some activity, or even that selection might act upon these. Only a fool would assume that in the absence of other consistently heritable influences, that most or all such heritable traits/features/structures/whatnot are encoded genetically. Only the most bizarre of minds would note that many obviously different species of organisms share similarities and idiosyncrasies of structure and biochemistry, contain no differing cell types, tissue types or even novel organs, yet cannot subsist on the diet of each other or interbreed.

Clearly, it is all the work of something more complex than earthly biology that can spontaneously assemble itself out of materials with none of the consistency of “normal” matter and then go about purposeful behaviour.

Rusty

Allelic mutation has never played a role in speciation or the formation of any of the higher taxa. As you say, only a fool would think otherwise.

I note that cosmologists are quite willing to abandon earthly physics to support their ends, but biologists are loathe to do the same. Besides, the PEH does not require any intervention by any higher power anyway, just the acknowledgement of the real world. I guess that is just not good enough for the garden variety Darwinian atheist.

John A. Davison

This, and the Times article discussed in the previous post, is a manifestation of the the wedge at work. The tactic is to make, as the renowned Darwinian, Sherlock Holmes said “To twist facts to fit theories rather than theories to fit facts.”

In so doing, they reveal their true objective: to promote their narrowly theocratic agenda.

John A. Davison: “I note that cosmologists are quite willing to abandon earthly physics to support their ends, but biologists are loathe to do the same.”

The perfect example of a creationist being either egregiously ignorant or diabolically deceitful. What “earthly physics” have been abandoned? Are you of the belief that theories that extend the present body of knowledge are evidence that the present body of knowledge has been abandoned?? This is one of creationism’s favorite strategies: argument by false dichotomy. And here’s a dichotomy that holds up: you’re either ignorant or purposefully dishonest (lying).

Mr. Davison,

Do you believe that natural selection can not have played a part in the creation of the variations of finches on the Galapagos Islands?

Mr. Davison,

You wrote, “Allelic mutation has never played a role in speciation or the formation of any of the higher taxa. As you say, only a fool would think otherwise.”

However an article from 2003 argues otherwise. See Presgraves D.C. et al (2003). Adaptive evolution drives divergence of a hybrid inviability gene between two species of Drosophila. Nature 423: 715-719. A copious literature supports the notion that incompatibility between homologous genetic loci prevents hybrid formation between distinct species. In this paper, two different labs built upon the work by Daven Pregraves, who showed that 20 different small regions of the genome of Drosophila melanogaster contributed to the hybrid inviability between Drosophila melanogaster and Drosophila simulans. One of these inviability regions mapped to cytological region 95AB on chromosome III encoded a nuclear pore protein, NUP96. Because nuclear pore complexes are large macromolecular assemblages with many subunits that all must fit together to form a functional whole, allelic differences in the genes that encode these proteins can potentially cause an inability to form proper, functional nuclear pores, and the nonfunctional pores would either cause cell death via nuclear leakage or inefficient nuclear transport. In the case of NUP86, Pregraves et al. use an ingenious hybrid rescue method that employed a small region of the D. simulans genome attached to the D. melanogaster X chromosome to show that particular alleles of the D. melanogaster NUP96 were incompatible with the D. simulans NUP96 gene. The lethality seemed to map the amino-terminus of Nup86.

Secondly, by studying the evolutionary history of NUP96, this paper shows that the amino acid substitutions in NUP96 in the two distinct species of Drosophila were drive by adaptive evolution. Polymorphisms at this locus in wild-caught flies showed selection for substitutions at specific sites instead of a neutral type variation based on genetic drift. This selection for distinct alleles at this genetic locus drove the generation of hybrid inviability between these two species of fruit fly. Work by Ayala et al. has show that once inviable hybrids are formed, natural selection favors the creation of prezygotic isolation mechanisms, since putting all your resources into making hybrids that do not survive is wasteful.

Therefore, allelic differences can and do drive speciation. I believe you should re-evaluate your position on this topic.

Sincerely yours,

Michael Buratovich

OMG!!! Michael, it sounds like irreducibly complexity is giving rise to (horrors!!) speciation and natural selection! Whatever will the Wedgies do now????

Unfortunately, they are unlikely to retreat in the face of overwhelming data, since they haven’t done so up to now…

Zillinger

Of course natural selection played a part in the varieties of Galapagos finches. I have never denied its role in subspeciation or the production of varieties. As far as we actually know there is only one physiological species of Galapagos finch.

The fact is that D. simulans and D. melanogaster are separate species by virtue of their hybrid sterility but it is not at all clear which form gave rise to the other is it? The arguments for selection are after the fact. Ask which was ancestral to the other and one is lost in conjecture. Even if I were to concede this rather trivial point, does anyone really think that this sort of process could ever give rise to another genus, family, order or phylum? I certainly could not.

I agree generally with Grasse that about all we see now is allele substitution and that sort of thing has absolutely nothing to do with evolution.

I refer you to the Prescribed Evolutionary Hypothesis manuscript for the reasons I feel as I do and for the sources that have influenced my conclusions.

John A. Davison

Zillinger

Of course natural selection played a part in the varieties of Galapagos finches. I have never denied its role in subspeciation or the production of varieties. As far as we actually know there is only one physiological species of Galapagos finch.

The fact is that D. simulans and D. melanogaster are separate species by virtue of their hybrid sterility but it is not at all clear which form gave rise to the other is it? The arguments for selection are after the fact. Ask which was ancestral to the other and one is lost in conjecture. Even if I were to concede this rather trivial point, does anyone really think that this sort of process could ever give rise to another genus, family, order or phylum? I certainly could not.

I agree generally with Grasse that about all we see now is allele substitution and that sort of thing has absolutely nothing to do with evolution.

I refer you to the Prescribed Evolutionary Hypothesis manuscript for the reasons I feel as I do and for the sources that have influenced my conclusions.

John A. Davison

The notion that single allelic substitutions can lead to speciation violates the metaphysical prejudice that big changes have to have big causes. One of the things that makes biology challenging is the way in which causes act at all scales from global environmental factors such as climate change to a single cosmic ray bopping a strand of DNA. The heterogeneity of it all is irritating, either because it outrages our aesthetic sensibilities or, more likely, because it takes entirely too much effort to understand!

Jim wrote:

“The notion that single allelic substitutions can lead to speciation violates the metaphysical prejudice that big changes have to have big causes. One of the things that makes biology challenging is the way in which causes act at all scales from global environmental factors such as climate change to a single cosmic ray bopping a strand of DNA. The heterogeneity of it all is irritating, either because it outrages our aesthetic sensibilities or, more likely, because it takes entirely too much effort to understand!”

Where in the world did you get the idea that speciation can only be brought about by big changes?

The notion that speciation requires big changes isn’t my idea. It’s pretty much a commonplace among creationists, however. I think it often lies behind the claim that macroevolution operates on different principles than microevolution.

I read a lot of 17th and 18th Century philosophy and science. In that era, writers made overt appeal to metaphysical principles such as the rule that the cause should be proportionate to the effect. It seems to me that much of Creationist and Intelligent Design thought recycles this sort of stuff though it was last up-to-date during the War of Spanish Succession. Unfortunately, even common sense comes with an expiration date.

There is no ‘mysticism’ in evolution. It is naturalistic, that is based on the concepts of natural forces. Mysticism implies some external supernatural force. That is the where the theists lurk, with their nameless intelligent designer and multitude of gods.

The theists like to misuse words constantly; and like to categorise the study of observable events as faith; but then we know their agenda. They want a return to times when if the church said the sun goes arund the earth everyone would say ‘yes sir’.

Still, lets pay attention shall we.

“natural selection promotes extiction”, I suspect you dont understand your terms, but yes NS does lead to extinction. That is obvious and implicit.

You should define ‘recently’ and define what you would accept as evidence. As you have said “ No prokaryotes please”, its clear you do not want anything that could evolve in a human time span, or even a lot few human time spans. So, it does look like you are prepped to reject any evidence I might find. It seems you want a evidence spanning tens of thousands of years. I think thats called loading the dice. Very useful when you dont want examples.

Evolution goes on…watch pests evolve resistance to insecitides. Its called co-evolution. You may not see it, but its there. Watch and wait.

John,

I wonder how you are so sure that allelic variation “never played a part in the formation of the higher taxa”. I’m hardly so certain. Their presence is demonstrable (indeed, ubiquitous), their effect considerable, their selectability and heritability iconic. You ask for no prokaryotic examples as they are boring. Yes, a boringly complete example of why they cannot be dismissed.

So, small mutations (point substitutions, insertions, deletions and minor duplications), being heritable, selectable, and capable of generating as much structural variation as might be between an irish wolfhound and a chihuahua, or between radish and canola, have no role to play. Pull the other one. Last time I checked the books, allelic variation was capable of generating overt changes in structure and biochemical function that exceed those visible between many related but clearly distinct species. I rather think the modern synthesis already assumes that more drastic genomic variations are required for significant alterations in body plan and development, and that these occur. Why imagine that the zygotes emerging from such are maximally adapted, or even had a hope if succeeding generations could not explore the new possibilities this allows for further allelic variation and selection? Why assume the big stuff is the key because it is indispensible, when the same is easily said for the little stuff? Both types of variation occur, both alter biochemistry and structure, and are heritable. Hardly coffin nails for the new synthesis.

Rustopher.

The irony over the creationist attacks on Kettlewell is that they don’t disagree with any of his premises. They admit that camouflage is in general beneficial to animals. They don’t argue that the cause of melanism in peppered moths is genetic. It demonstrates what they call microevolution and admit happens. But put it all together as literally a textbook example of evolution and the creationists go on the attack. So what if the photo of a moth on the trunk of a tree is staged. That photo of the president in the social studies book was staged, but that doesn’t mean that the book is lying about democracy (although the blue-staters might not agree.)

Now as far as our debate with John A Davidson, I finally figured out his agenda. He has some theory about meiosis and speciation that he’s furious that the rest of us haven’t accepted yet. As far as I can tell it’s about as far from the ID arguments as it is from mainstream science. It seems to be pretty much a one-man movement. I’ll throw him a bone and admit that natural selection stabilizes a population living in a stable environment and a stable ecosystem. Maybe he can go find a peer-review journal to publish his proof that all evolution ends when sexual reproduction begins. The rest of us have this silly view that shuffling the genes with meiosis increases variation within a population and so encourages evolution. But I guess I’m just being dogmatic.

Craig T

It is Davison, not Davidson.

It is the Darwinians that have a bone and like a dog they won’t relinquish it. I have already published my evidence in peer reviewed journals. Your last two sentences are right on. Shuffling genes never had anything to do with evolution. You get an A.

I am certainly not furious with the Darwimps, only disappointed in their blindness.

Much scientific progress has begun with one man movements. Lavoisier, Mendel and Einstein come to mind.

“All great truths begin as blasphemies.” George Bernard Shaw

John A. Davison

Does it bother any of the ID/Creationist crowd that the Catholic Church made its peace with Darwin around 1951? I had always thought that the CC had an edge over any “Creation” Research group in theological sophistication. Or is there another agenda at work here? Perhaps, as crass as it may seem, MONEY! Some obscure American prophet said something to the effect that ‘A sucker is born (reborn, perhaps) every minuite.’ Wish they’d send me some tithes. America held out such promise to the world. Now all we can offer is fear and darkness of mind and spirit. What further proof of evolution does anyone need?

The Catholic Church never made its peace with Darwin. It made its peace with evolution. Darwinism and evolution are far from synonymous. Evolution WAS a reality. Darwinism IS a scandal and a hoax and always was.

John A. Davison

I have a question. Slightly off topic sorry but I don’t know of a better site to ask. I read recently that the first evidence for life on Earth dates back to around 3.5 Billion years. Then a vast divergence of life (lots of new phyla) apeared about 500 Million years ago. Is this correct? In the 3 Billion year gap did more species of simple life evolve? If so would that not be an argument against ID?

Surely if the first simple lifeforms that we have evidence for occured so long ago, and the records show they survived for 3 Billion years. Then the argument between ID and Naturalism could be solved by showing the emergence of new life is an ongoing thing.

I am neither a proponent of evolutionism or ID just a confused but interested observer.

John, I never had the chance to meet Lavoisier, Mendel or Einstein on a blog, so I guess this is my big chance. What is your mechanism for evolution that Darwin overlooked? He concluded that all of the finches in the Galapagos were descendants of mainland finches modified through natural selection to fill specific niches on the new islands. How does your theory explain the Galapagos finches?

There are several distinct species of finch on the Galapagos. So far as I know, no one who claims otherwise has ever visited the islands, nor even bothered to look at the collection in the British Museum to suggest any way that the several species could be confused as one.

Peter and Rosemary Grant have the blood samples from each and every individual in at least three different species of the finches, over about 30 years, Dr. Davison. If you wish to argue that the species are not separated, the data exist for you to make the case.

I dare you.

From Comment #21171 by Stephen Elliott on March 20, 2005 11:05 AM

I have a question. Slightly off topic sorry but I don’t know of a better site to ask. I read recently that the first evidence for life on Earth dates back to around 3.5 Billion years. Then a vast divergence of life (lots of new phyla) appeared about 500 Million years ago. Is this correct? In the 3 Billion year gap did more species of simple life evolve?

Surely if the first simple lifeforms that we have evidence for occurred so long ago, and the records show they survived for 3 Billion years. Then the argument between ID and Naturalism could be solved by showing the emergence of new life is an ongoing thing.

++ + As this is off topic it may be moved to the ‘bathroom wall’.

Hi Stephen, sure, there were lots of species of simple life billions of years ago. But pardon me while I make things slightly less simple. First let’s distinguish between prokaryotes and eukaryotes. Prokaryotes, which came first, are things like bacteria and archaea that don’t have a nucleus in the cell like we more complicated eukaryotes (including humans, fungi, amoebae and algae) have. They also don’t have the flexible membranes that we have. Note that the 3+ billion year old traces of these tiny cells are very difficult to interpret; one can’t be absolutely sure one is looking at microscopic cell traces. Yes, there were lots of species between then and 600 million years ago but so far as we know these do not represent separate beginnings of life.

There are pretty good fossil eukaryote cells more than 1 billion years old. The first chemical signs of eukaryotes are much earlier, over 2 billion years old. However, these are traces of eukaryote membrane chemicals and do not necessarily indicate full eukaryotes as they now exist. Since modern eukaryotes evolved by engulfing or living symbiotically with prokaryotes, and since the eukaryote membrane greatly facilitates this, it is not surprising that new membranes came early in eukaryote evolution. Again, lots of species.

You jumped ahead to the period of 543-510 million years ago when multicellular forms first started to somewhat resemble modern forms. You skipped the period of 600-542 million years ago when diverse multicellular eukaryotes evolved but mostly did not yet resemble modern forms to the same extent. Recommended reading: Life on a Young Planet by Andy Knoll.

If so would that not be an argument against ID?

From a scientific standpoint there is no evidence for ID and hence nothing to argue about. From the intelligent design creationist’s standpoint, there is no such thing as a valid argument against ID because the Designer (formerly known as God) could have done it that way.

Then the argument between ID and Naturalism could be solved by showing .…

IDC is political creationism and cannot be ‘solved’ by evidence. Naturalism, is so far as it applies to science, just means following the evidence and taking nature, not scripture, as the final authority in scientific matters. Some people can’t abide this.

I am neither a proponent of evolutionism or ID just a confused but interested observer.

I’m glad you’re not a proponent of “evolutionism” whatever that is. Evolution is a well known process in nature. Evolutionary biology is the corresponding branch of science. Genetics, molecular biology, evolutionary biology (known as evo-devo for short) and paleontology are closely related fields. ID is the slogan of a movement in religious politics.

Dr. Davison said:

Here is a task for you. Pick a species known to have recently become extinct and show me the organism evolving to fill that niche. There are literally thousands of such organisms from which you can choose. Report back in a week or so. Good luck. No prokaryotes please. They are boring.

The same task could be done by selecting an entirely new niche, and looking to see what fills it.

The introduction of apples to North America created a niche for a pest that feeds on apples – other insects that affected apples having been left an ocean away. Tell us, Dr. Davison: From whence comes the American apple maggot?

Tell us from whence come bacteria that consume nylon? Were they carried on the ark by Noah?

One interesting story surrounds how the coyote “evolved” to fill the niche left when wolves were made extinct as the top predator in areas where sheep and cattle are raised. It’s not a clear cut story, but each stop involves evolutionary adjustments, and the sometimes unexpected results of those adjustments.

The history of Lyme disease presents another example. After the passenger pigeon became extinct, several species of mouse stepped in to fill their role as consumers of particular acorns. Alas for humans, that meant a proliferation of the mice, who were a link in the chain of existence for the organism that causes Lyme disease in humans.

Do you find maggots, coyotes and mice boring? Perhaps you are still entranced with actually putting your research where your argument is with regard to the several different species of finch in the Galapagos archipelago which you erroneously claim as one. Do you find prokaryotes boring because they so easily refute your claims?

Either way, I’ll wager that you don’t answer this post, Dr. Davison. It strays into areas of discussion you seem to avoid on this site – hard examples with real research backing them.

Dr. Davison,

“The Catholic Church never made its peace with Darwin. It made its peace with evolution. Darwinism and evolution are far from synonymous.”

It seems to me that the Catholic Church has made its peace with the modern theory of evolution, which includes but is not limited to Darwin’s theories.

Dr. Davison,

“The Catholic Church never made its peace with Darwin. It made its peace with evolution. Darwinism and evolution are far from synonymous.”

It seems to me that the Catholic Church has made its peace with the modern theory of evolution, which includes but is not limited to Darwin’s theories.

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P.S. Ed

I hate to belabor the obvious but…

bacteria that digest nylon are still bacteria

coyotes are still canines

mice that eat acorns made available by the extinction passenger pigeon are still rodents

Please provide me with an example of observed mutation/selection creating a

1) novel body type 2) novel tissue type 3) novel organ

I’ve asked for this time and time again and have never been given an example. That’s because it has never been observed.

There are two explanations, neither of which can be falsified or verified, for this situation:

1) mutation/selection acheives these things over timescales that are too long to observe

2) mutation/selection is incapable of acheiving these things

Do you agree so far?

Darwin is a metaphor. Obviously in 1859 he didn’t have all the answers, but he made a valient beginning. That’s the nature (dare I say evolution) of the process of shining light into dark regions of ignorance. Can anyone “see” the atomic structure of hydrogen? Can anyone “see” an photon? Can anyone “see” the speed of light or Plank’s Constant? Can anyone “see” the earth revolve around the sun?Can anyone show me a single scientific advance that can be traced to William Paley’s “Natural Theology”?

Sorry to bother again, but maybe people need to look at the York Groundsel. It’s a humble British fertile mutant. It’s alive! And it’s spreading to an ID research center near you!

To correct DS in 21315,

Bacteria metabolising novel compounds have a new gene that did not exist before. Genes are capable of modifying metablism and body structure to an extent that exceeds that visible in distinct species. That they are still bacteria does not indicate that something major has not happened.

Please give an example of speciation that in any way requires a novel body type, novel tissue type or novel organ.

You keep asking for this, yes, but you have never given an example where speciation required this. There are no novel tissues, body plans or organs in all of the mammals. Why must anybody regard your question or yourself as other than a child repeatedly asking previously answered questions?

The creationists keep harping about a being for which there is no evidence. JAD keeps mentioning a persistently absent and incompetant genetic engineer. Neo-Darwinists keep harping on demonstrable processes of genetic change causing observable developmental change in increments compatible with considerable change over extended periods.

Mutation and selection have been observed to achieve changes in structure and function of existing structures of more than an order of magnitude in less than one human lifespan. By means of photography, data collected now will reasonably be available in several generations.

So, “no”, I don’t agree with you and hope you live just long enough that someone with a lot of money to waste can demonstrate it.

The aim was never to satisfy your high-and-mighty hard-to-convinceness, it has been to advance our understanding and capacity to manipulate the environment, which selective breeding has done within recorded history. It is not compulsory that the whole process be observable by one individual. Like the curvature of the earth, things can be examined and known by other than simple inspection.

Be assured that when the trivial if long exercise of satisfying your particular demands occurs, we will be using the results as easily and effectively as the alleged assumption that prededed.

You stand corrected. Go cry in your beer, child.

Rustopher.

Rusty said:

Please give an example of speciation that in any way requires a novel body type, novel tissue type or novel organ.

Rusty, can you tell us what you’d consider a novel body type, or novel organ? For example, what organs do chimpanzees have that an insect, or squid, does not? What sort of “novel” body type, tissue or organ has arisen in the past 300 million years, in your opinion?

DaveScot said:

P.S. Ed

I hate to belabor the obvious but …

bacteria that digest nylon are still bacteria

coyotes are still canines

mice that eat acorns made available by the extinction passenger pigeon are still rodents

Then stopp belaboring the obvious. Dr. Davison asked for examples where creatures had moved into new or newly available niches. Each of those examples fits his criteria exactly.

So you wish to move the goalposts? Yeah, we know.

Please provide me with an example of observed mutation/selection creating a

1) novel body type 2) novel tissue type 3) novel organ

I’ve asked for this time and time again and have never been given an example. That’s because it has never been observed.

There are two explanations, neither of which can be falsified or verified, for this situation:

1) mutation/selection acheives these things over timescales that are too long to observe

2) mutation/selection is incapable of acheiving these things

Do you agree so far?

I did, and to the best of my knowledge, you never responded. Mosquitoes now digest DDT. It’s been observed and documented. DNA files exist if you’d care to inspect them.

1. Mutation/selection acheives these things and it has been observed.

2. See #1.

DaveScott

My dear man. You are asking for creationist magic.

Evolution works by small modifications to extant body types, organs and tissues.

What you want, expect and demand is a polymorph spell from Dungeons and Dragons.

Ed, your reading comprehension is down.

I was leaving “what is a new organ” as open as DS. DS is clearly demanding something overt like a liver, a spleen, a heart, a kidney, a bone, a brain, tissue with a novel function and structure. Within for instance the mammals there are no distinctly new ones. The odd gland here and there, the odd bellying and thickening of a luminal lining there, the massive expansion of certain organs and the vestigialisation but not elimination of others, yawn. Tetrapod, almost all major bones and organs represented with similar functions, though with massive variation in size and capacities. Since I rather think that mammals share a common ancestral population and that they (we) have evolved from same, why would the lack of a new major organ be any sort of criticism of evolution? Since clearly vast swathes of evolution do not require new organs, body plans, tissue types or cell types, why regard Ds’s question as meaningful?

Speciation (being a convenient unit of divergence) doesn’t involve new major organs. Phylumisation would, but that doesn’t happen enough to worry about. Your question on squid and insects implies that I don’t think these groups of organisms differ. I course I do. When they and mammal lineages diverged, they were not necessarily perceptible as differing in any of the respects in which they now do.

DS trivially gloats that a few dozen human generations of recorded selective breeding has not generated a second spleen, or a cellulose bone. I simply don’t see how that is a relevant criticism.

Rustopher.

Getting back to the main idea of the thread, I stumbled across this a little while ago http://www.nature.com/cgi-taf/DynaP[…]887940a.html

Since Dave Scott is quoting John Davison’s contention that evolution has stopped here is a link to two new species of lemur. Clearly the heard is not being thinned out. http://www.iucn.org/themes/ssc/news/newlemur.htm http://archives.cnn.com/2000/NATURE[…]/new.lemurs/

Aferensis

I don’t know what planet you’re living on but the earth is losing some 20,000 species annually.

Rusty,

I’m not criticizing evolution. I’m criticizing mutation/selection.

Mutation/selection is given as the mechanism that produces all creative change yet not a single one of the largest types of changes has been observed.

The largest change of course is biogenesis but that gets begged off too often as not part of evolution. Biogenesis not being part of “evolution” is absurd but hey, when in Rome. So I use the next largest category of unobserved creation - basic body plans, tissue types, and organs. Neo-Darwinists say they know how those things evolved so it’s certainly fair to point out that it’s a huge extrapolation from anything actually observed to happen. I don’t take things on faith. I don’t take religion on faith and I don’t take unobserved evolutionary mechanisms on faith. If the teaching of “evolution” in public schools just comprised the facts and left out the atheist dogma I wouldn’t have a problem with it.

Darrell says “Mosquitoes now digest DDT”

Big deal! Insects have been battling natural insecticides made by plants for a very long time. How do you know that DDT resistance wasn’t a recessive allele that was there all along? There’s probably natural insecticides made by plants that are chemically similar to DDT and there’s your explanation. It was a capability that was there all along.

Regardless though, it’s a still a mosquito.

And I responded to it last time you asked. It started a whole long discussion of what mosquitoes really feed on. A few dopes here didn’t know only females suck blood. Maybe 9th grade biology classes should spend less time on unobserved neo-Darwinian atheist dogma and more time on facts like what mosquitoes do for a living.

Next!

Rusty,

20,000 years of dog breeding has not produced a single novel thing in a dog that isn’t entirely a matter of a different scale of some existing thing. I believe that works out to around 1000 human generations, not a few dozen. Not only that, but the normal rules of fitness didn’t apply, because humans were doing the selecting. So it’s like 20,000 years of uber-evolution.

I don’t consider scale changes to be remarkably creative. These are just minor variations around a larger theme that stays quite intact.

Dave Scott: I’m living on a planet that, although it is losing species - mainly due to human activity, is also generating new ones - as the new species of lemurs show. Perhaps you should follow the links. Better yet do a google search on new species.

Has anyone noticed that crows are doing really well? There seem to be a lot more crows now than when I was a kid. Why do you suppose that is? After all, California Condors are quite rare. Don’t they partially live in the same niche? Aren’t they both essentially scavengers?What is allowing the crows to do well and the condors to do poorly? Could it be “Natural Selection?” If the condor became extinct, wouldn’t the crow do even better? Wouldn’t there be more food for the crow?

If you are looking for extinction/niche filling, you need to go no further than that. After all, that is how it works. It isn’t something becomes extinct THEN something fills its niche, it is something is better equipped for a certain niche and it could lead to extinction. This species may not become extinct but find a different niche. No wand waving. No new magical beast taking its place. It is just how nature worked, works, and will forever work.

Rusty,

If bacteria couldn’t cope with a wide variety of poisons they wouldn’t be the most successful (by biomass and number of individuals) form of life on the planet. I’m sorry if I yawn at antibiotic resistance in bacteria as convincing evidence that bacteria mutated into badgers via mutation/selection. If you can show me, for example, an extant bacteria that mutates into a yeast I promise I won’t yawn at that and will consider it convincing evidence of the power of mutation/selection. Good luck.

In the meantime I think the door should be left open a crack for other explanations, including design, in the set of possible mechanisms underlying biologic evolution. That’s not unreasonable.

Hi DaveScot,

This theme seems to pop up in lots of these discussions, and I lost track of where you may have responded, so I’ll ask here (and hope it doesn’t get lost) - why do you think that the work of Doebley and his coworkers is not a good example of novel organs or body plans evolving? (I’d be more specific, but you have indicated that you are well-read, and thus that you probably know off the top of your head what I am referring to.)

Thanks for helping me navigate these Panda’s Thumb discussions.

20,000 years of dog evolution has created a ring species. And yes, it is true that related species share many features, but that is what you expect of neo-darwinism.

Evolution says closely related species will resemble each-other. Distantly related species will look like they are distantly related and extremely distantly related species will show few similarities.

Once again it seems you do not understand the concepts you are attacking. You want a dog to turn into a bird, and a fly into a horse, all in the blink of an eye.

That is, you want magic.

Still, I shall indulge you.

A tortoises are turning into giraffes.

On the galapagos islands the saddle back tortoise is note worthy for the raised ridge above their necks, their long necks and their long legs (long is by comparison to dome backed tortoises). What is significant about this?

Simply, like giraffes of the African plains, these changes allow saddle back tortoises to reach leaves that are out of the range of competitors. Thus, faced with the same problem as a giraffe it adopts the same solution.

Satisfied?

Afarensis

Evolution covers a lot more ground than minor variations that produce lemur populations that are considered a new species by some arbitrary artificial system of classification.

You’re defending microevolution when no one here, especially me, is attacking it!

Abiogenesis and evolution of higher taxa are where I am skeptical of the mutation/selection story. There is no compelling reason to believe that the process, whatever it was, which produced the first cell and thence the higher taxa is still operating today. That macroevolution is still occuring is just another bit of neo-Darwinist dogma that must be accepted as a matter of faith. Spare me the faith, just the facts please.

20,000 years of dog evolution has created a ring species. And yes, it is true that related species share many features, but that is what you expect of neo-darwinism.

Evolution says closely related species will resemble each-other. Distantly related species will look like they are distantly related and extremely distantly related species will show few similarities.

Once again it seems you do not understand the concepts you are attacking. You want a dog to turn into a bird, and a fly into a horse, all in the blink of an eye.

That is, you want magic.

Still, I shall indulge you.

A tortoises are turning into giraffes.

On the galapagos islands the saddle back tortoise is note worthy for the raised ridge above their necks, their long necks and their long legs (long is by comparison to dome backed tortoises). What is significant about this?

Simply, like giraffes of the African plains, these changes allow saddle back tortoises to reach leaves that are out of the range of competitors. Thus, faced with the same problem as a giraffe it adopts the same solution.

Satisfied?

Pete Dunkelberg, Thanks for your answer. However recomending that I read a certain book is not an option in the near future. Somebody else previously recomended that I read “Biology” by Neil Camdbell and Jane Reece. I ordered and had it delivered 2 days ago. The damn thing must way about 10lbs and is likely to keep me busy for the next few months if not years.

DaveScot: 20,000 years of dog breeding has not produced a single novel thing in a dog that isn’t entirely a matter of a different scale of some existing thing.

Just out of curiosity, what would you have selected dogs for, over 20,000 years, that would have constituted “a novel thing”? Wings? Altered gene expression in the brain? Webbed feet? Do you realize that generating “novel things” or proving evolution to doubting creationists was not, and still isn’t, high on the to-do list of dog breeders?

Objectively, dogs, with their extreme morphological and behavioral diversity (which in fact is quite comparable to that of existing natural species of canids), provide very strong evidence for the ability of selection to drive evolution. To think that this was accomplished in a few thousand years (in fact, for most breeds, a few hundreds), is just mind-boggling. It also underscores the role in evolution of population genetic structure and of recombination, a fact that most creationist seem to forget in their rush to tear down their mutation/selection strawmen.

Well, if I was going to go for selective breeding of specific features in dogs.…

I would breed them so they could speak.

Dog: “I (food) Love (food) You (food)!!!”

Dog: “what do you mean ‘bad dog’? Who are you to judge me?”

Me: “Umm, you’re right. have another biscuit.” (shuffles off)

Maybe its just me.

Dave, You are missing the point. You said evolution has stopped. I pointed you to two new species - created by evolution. I wasn’t defending “microevolution” Just pointing out an example were evolution had occured. Since you wish to arbitrarily and articicially separate micro and macroevolution - where exactly do you think the new taxa come from if not from species? Did mammals spring forth, full blown as a class from the egg of a theraspid reptile? Or is the reptile-mammal transition not macro enough for you?

You said evolution has stopped. I pointed you to two new species - created by evolution.

They were merely discovered, go read the articles again.

Syntax Error: mismatched tag at line 2, column 314, byte 374 at /usr/local/lib/perl5/site_perl/5.16/mach/XML/Parser.pm line 187.

Jeff, I interpret this “An international team confirmed the new varieties by genetic tests as well as by measuring small differences in their skulls, teeth and other physical characteristics. It’s incredibly rare to discover a new species of primate, let alone three new species,” to mean exactly what it says, namely new species. (italics mine)

Dave,

Your objection is that phylumisation hasn’t been demonstrated in your life span. Yawn. Mutations keep coming up, and if enough to give dogs varieties that can still interbreed (chihuahuas and Irish wolfhounds don’t manage well), brassicas a few that can and a few which can’t, and distinct species that can only just barely form hybrids and most sterile such as horse/donkey and many figs.

Like forensic investigation, the idea is to establish what we will never be able to see directly. Plenty of mutations occur. Once enough have occurred that the new variety is able to occupy niches that the ancestral form did not, yet more mutations are not unreasonable to assume. If enough time has passed, sufficient mutations accumulate. Who is to say what that many mutations cannot under any circumstances achieve? The demonstration that a whole genome might be gradually displaced by mutations and duplication events and chromosomal rearrangements requires only time, which keeps passing, and mutations, which keep occurring. You have not yet demonstrated how mutations would fail to accumulate over time. Since you cannot demonstrate that they do not, nor can you demonstrate that that such do not have profound (if individually small) effects on the features of the lineage, you are also unable to state that mutations could not as opposed to might not generate considerable change over time.

Rustopher

I am sorry, but this debate is going nowhere, and it has nothing whatsoever to do with the original topic. People are asking over and over the same meaningless question - show me an instance of speciation - and others are taking the bait. The question has been answered abundantly, and we need not rehash it here. I will cut off comments shortly.

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This page contains a single entry by Matt Young published on March 18, 2005 5:24 PM.

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