Say C is insects, B is “fish”, and A is mammals. The fish that exist today have just as long back to their common ancestor with C, as A does.
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Doesn’t Behe accept evoluiton except for a few biochemical structures which he claims are too complex to be explained by evolution alone?
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Why should anyone care about this?
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This is a mistake that creationists (and the general public too) commonly make about the evolutionary scenario, one that Michael Denton famously makes in Evolution: A Theory in Crisis. The correct answer is that the common ancestor of insects and fish is the same as the common ancestor of insects and mammals. Fish and mammals are equally related to insects.
This misunderstanding relies on the view of evolution as a sort of ladder, in which fish give rise to amphibians, amphibians to reptiles, reptiles to mammals, and mammals to humans at the top of the ladder. But in fact the more proper view is of a tree, in which all the modern species are twigs, equally far from the roots.
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I take you to be answering the second question, rather than the first. And I sense some progress here.
I understand why you’re saying that, but it sounds like you aren’t thinking about modern creatures. Your answer would be correct if by “fish” we mean the first fish. But what if we don’t mean first fish, first insect, and first mammal, but modern insects, fish and mammals? Remember, we’re talking about genetic comparisons, so we don’t have the data to say what, for example, some ancient ostracoderm’s Cytochrome C looked like. When the issue is genetic comparison, we’re generally dealing with modern creatures.
So with that clarification: are modern fish more closely related to modern insects than modern mammals are?
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You are using what I call the frozen frog fallacy, since I fist met it with connection to amphibians.
The fish from which mammals are descended lived in the Devonian, and that fish would certainly be closer to an insect than any mammal, at that time far in the future.
However, all the descendants of that fish, including today’s fish and today’s mammals, have continued to evolve with roughly the same rate of mutation.
All this would come immediately apparent if you take the trouble to look at any phylogenetic tree. The results are often quite contrary to common sense. For example, since the last common ancestor of sharks and bony fish is further away in time in the last common ancestor of bony fish and mammals, a catfish is more closely related to a cat than it is to dogfish.
Does that help?
The frozen fish fallacy was used to great rhetorical effect in the notorious Of Pandas and People, the book at the centre of the Kitzmiller versus Dover Area School Board trial.All those responsible for that book and for urging it on students should be deeply ashamed of themselves.
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The ancestor of all vertebrates parted company from the ancestor of today’s insects long before tetrapod’s branched off from other vertebrates. Therefore in terms of time (and roughly in terms of number of mutations) all modern vertebrates are at the same distance from a bumblebee.
You are more closely related to your siblings then you are to your cousins, but all of you, siblings and cousins, are equally closely related to the grandparent you have in common.
Does that help?
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And to my knowledge, @Eddie, Denton has never forthrightly admitted and retracted that. Just another data point on DI integrity.
More detail on this howler is provided here:
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I won’t claim to understand your perspective here. We have Behe’s opinion on one side and continual scientific confirmation and progress on the other. We also have Kitzmiller as confirmation of ID misinformation - representing Creationism as some sort of science. I get that your faith may lead you to not accept evolution, but that doesn’t require you to accept misinformation in support of your faith. That just seems … kind of wrong … from any perspective
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That’s actually a different and considerably later howler.
A similar post at Panda’s Thumb:
Well, as you can see, several people have pointed out the right answer, and explained it very capably. I would just add that when one sees things like this misstated in anti-evolution/creationist books, e.g., Pandas and People or Denton, it’s very telling. It’s not a hard concept at all to grasp, and as the question is only what evolutionary theory should predict, a “wrong” answer isn’t even in the zone of the arguable; evolutionary theory does not, in fact, predict a greater distance from insect to mammal than from insect to fish.
And so that leaves you, I think, with a puzzle. It is not always susceptible to easy solution, but sometimes it is. The concepts here are extremely basic and should be known to anyone claiming familiarity with general biology. And it ought to, but so often does not, go without saying that for someone to mount a worthwhile critique of core concepts of biology, he must first, before all else, understand those concepts.
So this is the puzzle: when someone falls down on the job that spectacularly, as the Pandas authors do and as Denton does, what can you make of it? There really are two principal options, though the truth might be, sometimes, a blend. The one is that these people do not understand; it’s a mistake. If so, they have no business claiming to be able to mount a worthwhile critique, and that ought to be the end of it. And the other, of course, is that they wish to mislead their audience into thinking this is a genuine problem which evolutionary theory cannot resolve. That, too, ought to be the end of it.
But the answer which is not available is that this is a mistake which is not particularly discrediting, and which may occur in the course of work which is otherwise worthwhile. The “mistake” is vastly, vastly too simple and too obvious to be consistent with competence and honesty. It must be inconsistent with at least one.
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I stand corrected. I guess that’s why we have to read all of the books! 
From that it would appear he has realized the error he had made earlier. I wonder if he has ever acknowledged and corrected that one.
I will say that is a rather clever “argument” Denton makes there. It is not as obviously wrong as most ID arguments. But, like all religious apologists, he stops investigating the science when he reaches the point that he can make an theological argument, and fails to determine whether the problem he has identified has already been addressed.
I will have to admit that Ernst Mayr, before there were any DNA or protein sequences around, made a similar mistake, predicting that similar morphology would result from similar genomes, so that fish would indeed be genetically closer to other fish than to any mammals. And one corollary to that was that frogs would be genetically “primitive” and thus insects would likely be more similar to them than to mammals. Of course he was wrong about that, as it turns out.
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I always think of his remark about the search for homologous genes being futile except in close relatives. The man was immensely clever, but of course, he was not infallible, especially on the subject of things not-yet-known.
Yes, but my parents would be more closely related to the grandparent. And aren’t phylogenetic trees ordered by molecular distance? Humans are placed closer to chimps than to gorillas, because of molecular distance…
A lot to unpack here! FIrst off, Behe makes scientific arguments, his books are not just opinion pieces. And creation could be detected by science, mainly by forensic science, such as the initial distribution of energy in the big bang, the information in DNA, etc. I don’t accept misinformation, that is why I changed my view when I read Behe, after reading Miller.
Notably in the area of blood clotting, where as I recall (it’s been over a decade now) Miller paints a picture of lobster clotting, with a simple Y diagram, and concludes “how simple it is to evolve this.” Behe gives the picture of human blood clotting, with factors piled on factors, a veritable train station of crossings and recrossing, and comments about how changes to such a system would likely result in all our blood clotting, or not clotting enough. The conclusion then being that blood clotting is not simple to evolve.
Hopefully only one of them.
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