Many people would have nothing to discuss. 
The world might just become a better place then 
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It doesn’t stop 'em! I am sure that is true in every field. As a lawyer I had some astonishing conversations. I recall one fellow who was sure that the US Supreme Court had ruled that income tax was unconstitutional. I had a client (my YEC client of whom I have previously spoken) who had a meritorious claim, but who was also convinced that the way to win our case was to file a bunch of what he called “common-law liens” on the property of the defendants – the sort of thing which would probably have concluded with my disbarment, had I not refused. I have the Establishment clause “explained” to me over and over again by people who have no idea of its history or of scholarly and judicial interpretations of it.
One has got to always ask oneself: am I doing that? If I am, I should stop. If that question were asked more often, ID would cease to exist except, perhaps, as a peculiar fascination of Michael Behe.
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this isnt true. we can prove that bacteria exist for instance. this is a fact, not a theory. the same is true for the flagellum evolution- its just a theory, not a fact. so we basically have a fact (motors need design) vs a belief that they dont.
i actually read actuall science. so please refer to my question. can you find any calculation for the chance of the flagellum to evolve? if not i just rest my case since there is no such calculation in the scientific literature. and if there is no such calculation we cant know if its even possible.
I hate to take you down a philosophical rabbit hole as I do not think it will help you. One does not “prove” an observation, even a pedestrian and uncontroversial one like “bacteria exist.” All one can say is that the proposition that bacteria do not exist would require one whopper of an alternative explanation for a wide range of observations.
Now, if we discard those philosophical possibilities, such as “we live in The Matrix” or “an evil scientist has my brain in a vat and is feeding it false sense impressions,” then for practical purposes we can say, indeed, that the existence of bacteria is a fact. But your notion of “fact” is extraordinary, because it includes this sort of thing:
That’s not a “fact,” but a proposition about causes. A proposition about causes cannot be “proven” in any sense. It may be decisively shown to be false, or evidence may be found which tends to confirm it.
So, where we are is back to your habit of making weak analogies. “Motors” in the ordinary, everyday sense of the term – mechanical devices driven by some external power source, composed usually of parts made of metal and plastic, and driven by such things as coils of enameled wire which are drawn through dies in wire factories by human machine operators, do always result from human manufacture. Bacterial flagella never do; they only result from the reproduction of bacteria, a process in which no manufacturing methods employed by humans are ever employed.
As I explained previously, the strength of an argument by analogy depends upon the extent to which you can show that the two phenomena are alike in all relevant respects. If you can, the argument becomes persuasive – not a “proof,” but persuasive. If you cannot, it is utterly useless. Here, your analogy rests simply upon using the word “motor” to describe two things which are about as unlike as can be. It is charitable to describe that as an analogy at all; but if it is an analogy, it is one which has no persuasive power at all.
Why do you believe that is a good, or even worthwhile, question? If you think it’s a good question, do the work and figure it out. I think that what you will find is that since there is a great diversity of bacterial flagella, and a great complexity to biochemistry, and a great void in our knowledge of the genomics of primitive prokaryotes, such a question is not answerable in such terms, which is why nobody bothers to ask or answer it. And, by the way, I doubt very much that you do read actual science. You have said things about every organism “probably” containing “unique biological systems.” Both the generality and the incorrectness of that statement suggest that you really do not know anything about it. I am not trying to be unpleasant about it, but you really do need to acknowledge that you have not really even begun to consider the question of the origin of the various forms of bacterial flagella, much less reached the point where you can draw conclusions.
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Can you find any calculation for the chance the flagellum will be designed and manufactured by some intelligent designer?
No? Weird. Why do you hold hypocritical double-standards?
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By way of further response:
Declaring that something is impossible because you cannot see how it is possible for ANY natural cause to bring it about is extremely hazardous unless you are in possession of a tremendous body of information about the entire depth and breadth of those natural causes.
But even if you ARE in possession of such a tremendous body of information, it’s still hazardous. Consider, for example, work on the combustion of the sun. Back a number of years, people used to work out how much hydrogen the sun could have in it, and how long it would take that hydrogen to burn up, generating the heat and light output of our sun. Their work exhausted all known physical processes quite well, and the conclusion was that the sun was of very limited life. But there were unknown physical processes: fusion, most notably. So you can know all that humanity knows, use that knowledge carefully and systematically to reach a perfectly reasonable conclusion, and be wrong by many orders of magnitude.
In the present case, however, nobody really needs to know the question you are asking. What is the probability that the flagella of various types of bacteria all arose at some point? One. How did it happen? Only investigation into the proximate causes of organismal features can help us answer that. Are we guaranteed definitive and final answers? No.
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No, @scd . We can compile evidence that bacteria exist. Proving and proofs is something done in mathematics.
As a has-been linguist, I will agree that the English word “prove” has multiple definitions in general conversation. But when we discuss science—especially within forums focused on science—we do well to adhere to the precision of academic/scientific terms. This will save a lot of confusion and equivocation fallacies.
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Motors needing design is a theory, not a fact.
In addition, we can’t know if it is impossible for evolution to produce a flagellum.
That’s very true, and causes confusion when disciplines like science and law meet. In the law, we say a fact is “proven” if the finder of fact concludes it is true, based upon the evidence. But a fact “proven” in court may actually be false. Innocent people have been executed, because they were proven guilty. And, of course, the law, like science, can never “prove” a fact in the philosophical sense.
I am not sure to follow you here. Indeed, the remarkable thing in gpuccio’s figure is not the sequence divergence but, on the contrary, the high level of sequence similarities that is observed for the six proteins between humans and the common ancestor of fishes. Given that fishes appeared more than 400 millions years ago, it means that these similarities have persisted through deep time. As such, they allow to estimate the FI of the six proteins at the dawn of vertebrates. Now, the level of sequence similarities between pre-vertebrates and humans for the six proteins is much less than what it is between humans and fishes. Hence the information jump associated with the transition to vertebrates.
Aren’t the similarities explained by common descent(they are the same because they were inherited as-is from a common ancestor), and the differences(where the sequences diverge) explained by the independent accumulation of mutations in those different lineages?
Is it not also an interesting fact to you, that we can pretty much elucidate the evolutionary relationships of these species from each of those genes, and that they would very significantly corroborate the same branching pattern of descent?
But they don’t allow you that for reasons explained so many times before. We’ve been over this, they persist without changing because they are retained by natural selection. In the context of the rest of the sequence, those amino acids epistatically interact to perform the function of the protein, and among sampled mutants they were higher fitness variants.
We’ve been over this. A local optimum(within the immediate sequence neighborhood, these residues in this particular sequence have the highest fitness), epistasis(multiple amino acids in the sequence affect each other, hence why some resist change while others do not), and purifying selection(those with the highest fitness are most likely to persist), among other things.
Yes because more time has passed, so more sequences have been sampled by mutation and selection, so potentially neutral or adaptive changes have had more opportunities and time to accumulate.
There isn’t any reason to think there is an “information jump” going on (at least with respect to how functional information, FI, is defined). But if you really want to call the gradual divergence of sequences in vertebrates, from sequences in invertebrates, an information jump, then okay. Then that information gradually increased over that ~170 million year period between the common ancestor of the depicted invertebrates and the common ancestor of vertebrates. As vertebrates evolved over that period, there occurred mutations in the protein sequences that had higher fitness in that sequence context, and they were subsequently retained by purifying selection, explaining why they didn’t continue to change.
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Sequence conservation from a single starting point can not tell you how many starting points there are. gpuccio’s method can not measure functional information.
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Not my field of expertise, but just one point to add:
I think that there is some evidence that both tunicates and cephalochordates (especially tunicates) have had some significant secondary loss of features. If that’s so, one has got to be very, very careful when one is tempted to think of them as modern relict creatures which can be used as analogues to our common ancestors with them. I do not know how this might correspond to measures of sequence similarity but I would think that it complicates the picture.
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I don’t think that’s relevant in this case. When it comes to comparing homologous protein-sequences from two species to calculate the pairwise sequence-identity, it doesn’t matter whether the differences in those sequences are due to deletions, or just substitutions, they will be counted as as not identical and thus reduce the %identity.
Substitutions can still potentially count towards an overall similarity score(because some codon exchanges are more likely due to the structure of the genetic code, which usually result in chemically and physically similar amino acids), which is not the same as pairwise identity however(which is where the sequences are completely identical).
What you’re suggesting might however help explain why some residues could be under less constraint in species that have seen other gene-deletions, as they could have lost other intermolecular epistatic interactions that would have constrained their function. That would be totally speculative though.
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Ah! Thanks!
As should come as absolutely no surprise to anyone with only a grade school level understanding of evolution.
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thanks. so we can prove things in biology.
so a spinning motor doesnt necessarily need design? as i said: lets agree to disagree.
because if you cant say what the chance to evolve the flagellum then you cant say that its probable to evolve it.
yep. extremley high since we know that motors are product of design.
so you cant be sure that bateria exist?
I don’t see any calculation here. How would you calculate the probability? Show your work.
If I were to be generous and take that to be an argument, it would commit the fallacy of a hasty generalization. Or as an inductive argument it would violate the principle of total evidence and thus commit the fallacy of exclusion.
We know that some motors are the product of human design, we don’t know that all motors are. In fact, we know that some motors are not the product of human design. Incidentally we also happen to know they’re the product of evolution, but even if we did not, that would just make us ignorant about their origin and so you would still have all your work ahead of you.
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That’s an incredible non sequitur.
Evidence and proof are not the same thing. Compelling evidence drives science. Proof drives mathematics.
I’m curious: Did you ever study proofs in a high-school geometry class?
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