I believe he means “Unapologetic Catholic” who was active here back when Eddie was posting as “Rich.” Rich posted often about internal whale testicles, seeing them as a sign of intelligent design. But cryptorchidism is common among terrestrial mammals, including humans.
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I can’t even.
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That’s not the way you presented it. Where did you read this?[quote=“Eddie, post:35, topic:26141”]
I cannot think of a source where it is claimed that the dark variety only came into existence for the first time during the Industrial Revolution.[/quote]
And I cannot think of a source in which the opposite was claimed. What is the source for your claim?
There is one important fact we do know, and that is the ratio of new mutations to existing polymorphisms.
[quote]If I’m wrong about this, I’ll gladly accept correction.
[/quote]So you throw out hearsay without a source and demand that others show that you are wrong?
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That’s just about perfectly backwards. If you happen to be dealing with a well-studied species, observational history may be able to tell whether a phenotype was common, but if it was uncommon, it can’t tell you whether any occurrences were the result of recurrent mutations which were then lost to purifying selection, or persistent variants that happened to be at low frequency. DNA, on the other hand, preserves the actual history of the variant(s) that increased in frequency, and can tell you whether selection was acting on a recent mutation or old, standing variation.
In the case of peppered moths, the first dark form was reportedly observed in 1848. The genetic evidence is that the dark phenotype was almost entirely the result of a single recent mutation. The evidence I was thinking of was that described here, but I see that another paper on the subject came out this year (well summarized here). The latter places the most likely time of the causal mutation in the early 19th century, although with substantial uncertainty.
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There is one area where scientists are divided, and that is whether Natural Selection is Group selection or Individual selection. George C. Williams wrote an important book against Group selection which influenced Richard Dawkins and his Selfish Gene. Later he softened his stand in this area.
E. O. Wilson at first went for Group Selection, then agreed with Dawkins, but recently went back to Group Selection to the dismay of Dawkins. Stephen Jay Gould also disagreed with Dawkins on this point.
Group Selection vs Individual Selection mirrors the One and the Many issue of philosophy and theology. Life and Reality are unified, and so science, philosophy, and theology are connected.
I really don’t see how anyone can mandate a Universal on this particular idea. Sometimes evolution rests on a single mutation… and that carries the day for a new sub-population.
Sometimes evolution rests on a mutation steadily working its way through an entire population…
Vagaries of environment and circumstances are constantly fluctuating. Trying to mandate either as a Constant seems like a fool’s errand.
Then your epistemology need work.
I looked it up because you mentioned it. How does confirm your approach?
I already stated this in my previous response, but I must have been unclear. The genetic data tell us that the variant that increased in frequency was the result of a recent mutation, and was not circulating in the population for a long time. That is true if the first black form was seen in 1848, and it would be true if black forms had been seen every ten years for the past two thousand years. The observational evidence cannot distinguish between a long-term mixed population of dark and light forms and a light population in which dark mutants arise from time to time only to quickly disappear because of purifying selection. Only the genetic data can tell us that. In this case, what the observational evidence can suggest is that mutations that cause the dark pigmentation are likely pretty rare. But given how spotty the observational record is, that conclusion no doubt has a substantial uncertainty attached to it as well.
Sure. How would you characterize the date arrived at by the observational evidence?
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In your paper, Ms. Katrina Rider “asserts” the peppered moth story is a hoax. She conveys the impression that dead moths were glued to trees as part of a conspiracy of deception. She seems unaware that moths were glued to trees in an experiment to assess the effect of the density (numbers) of moths on the foraging practices of birds. Taken out of the context of the purpose of the experiment, the procedure does sound ludicrous.
But, should we blame Ms. Rider for her outrage upon learning that moths were glued to trees? No. Instead, I blame Dr. Jonathan Wells, who wrote the article she cites as her source of information. While he has done no work on industrial melanism, he has written opinion about the work. To one outside the field, he passes as a scholar, complete with Ph.D. Unfortunately, Dr. Wells is intellectually dishonest.
Majerus’ detailed explanation of the specific ways in which Wells misrepresented him, can be found here.
Preamble about my book and quotes from it: Dr Wells wrote:
"Majerus’s book includes a chapter entitled “The peppered moth story dissected.” Surprisingly, on the first page (117) of that chapter appear both of the following statements:
“…the basic peppered moth story is wrong, inaccurate, or incomplete, with respect to most of the story’s component parts.”
and
“…in my view…differential bird predation…in habitats affected by industrial pollution to different degrees, is the primary influence on the evolution of melanism in the peppered moth.”"
It is worth showing the way in which Dr Wells tries to distort what is said by someone else in good faith, by giving the whole of the sentence from which the first quote was culled, and the ensuing sentence…
"The findings of these scientists show that the precised description of the peppered moth story is wrong, inaccurate, or incomplete, with respect to most of the story’s component parts. When details of the genetics, behaviour, and ecology of this moth are taken into account, the resulting story is one of greater complexity, and in many ways greater interest, than the simple story that is usually related.
In other words, it is the text book precised account of the peppered moth story that I critise, not the scientific accounts published in peer reviewed scientific journals. Dr Wells as a scientist should understand the difference between the two, and should not attempt to take quotations out of context for his own ends. That is a policy followed by the worst aspects of the gutter press.
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If experts keep telling you that your common-sense points are wrong, it’s probably because your common-sense points are wrong.
Right – that is your point. It’s wrong. Not certainly wrong, but probably wrong. If the dark phenotype had been present at 10% from the 1600s through the 1800s, and the genetic data show that the current dark phenotype is caused by a very recent mutation, then something other than your simple story of selection on an existing variant was probably going on. It’s wrong because neutral alleles at 10% in a large population are typically quite old – maybe 50,000 years old for something like a common insect. That’s inconsistent with the genetic data.
I can think of two scenarios in which both facts – the 10% historical phenotype and the genetic evidence for a recent mutation – are true. One is that the dark phenotype was caused by a recent mutation (say in the 1500s) and rose rapidly to 10% because of positive selection. In that case, something other than the Industrial Revolution was at least partly responsible for the rise of the dark phenotype, since it occurred before the IR. The other is that the modern dark phenotype is the result of an independent, very recent mutation, and that it replaced the previous dark phenotype. In that case, selection was likely operating on something other than the dark coloring, since the existing dark allele wasn’t selected for.
Now, there are observations that could change my assessment of the situation. For example, if the entire population showed signs of having rapidly expanded within the last few hundred years, then a 10% neutral variant would have a higher probability of being young. Or if there were a large inversion around the causal allele, then the mutation might not actually be recent. But these possibilities can only be explored by learning more about the genetics of the population, not by simply ignoring the genetics.
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Observations of a stochastic process always require a probabilistic context to be correctly incorporated into a theory. The criticisms I have seen lobbed at evolutionary biologists, however, often do not perform the probabilistic analysis correctly, if at all.
Fortunately, @glipsnort has introduced the genomic evidence that points to a recent mutation as the source of black coloration in the moths, so the scientific process seems to be proceeding the way it should. You should sleep well tonight with this reassurance. Good thing: you’ve got a lot of teaching and writing to do! (Godspeed in those endeavors, btw.)
And that’s how it’s always been portrayed in the scientific literature I’ve read. You have complained, Eddie, about evolutionary biologists’ supposedly making mountains out of molehills, and supposedly claiming that this single experiment constitutes Q.E.D. proof of the most important theory in biology Your prose made me chuckle, Eddie. The scientific community has never, AFAIK, claimed anything remotely close to that. Perhaps you could provide a link to some outrageous quote I never read?
Surely your indignation would be put to better use were it to be directed at Islamist terrorists or politicians who tell audacious lies. Due to unfortunate recent events, we have great need of your logic and righteous anger on this side of the pond.
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Really? Here’s your most recent statement on the matter:
I see you wrote this earlier:
If the general public misunderstands something, I am not surprised. We just elected a guy on this side of the pond who says five impossible things before breakfast, every day. Or as Mencken put it, “Nobody ever went broke underestimating the intelligence of the American public.”
I’m not inclined to share your criticism of vocabulary among scientific writers. I’ve read the same literature as you, so far as I can tell, and I never once came away with the same impressions you have.
btw, if you happen to notice when Wells’ new edition is published, btw, please let me know. I’m sure it will be interesting.
Godspeed,
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Continuing the discussion from What is the real deal with the peppered moth?:
George, if something is “constantly fluctuating,” then this changing is a “Constant.” I see nothing foolish in this although it does not conform to what we usually consider a constant. We need to think “outside the box.”
My position is that changes in the environment which are constant, and follow an overall pattern, which drives variation and evolution as found in the Peppered Moth story. If you have exceptions to this rule, please bring them up.
You can’t really do that with words Roger. Just because a verb can be modified by the adverb ‘constantly’ does not mean that said action can be interchanged with the noun ‘constant.’ ‘Constantly’ and ‘a constant’ have etymologically related, but not interchangeable meanings. Then you switch to the adjective ‘constant,’ which actually is more interchangeable with ‘constantly,’ but you act like that sentence “changes in the environment which are constant (i.e. happen constantly)” is somehow equivalent to “changing is a constant.” But “changing is a constant” means something different. This kind of playing around with words habit makes trying to understand what you are saying and following your logic very frustrating.
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So, Roger, what exactly is CONSTANTLY happening? Sometimes a population changes because of a single mutation … sometimes a population responds to group selection factors.
All I can see being demonstrated is: “Something different is happening all the time!”
As I said very early in this discussion … the inherent limitations of the Moth study makes for a less than satisfactory discussion, compared to the potential of the high-speed video of bacteria evolving in the face of an increasingly toxic environment.