Typology is perfectly consonant therefore with descent with modification. Each cladogram is witness to descent with modification and the existence of distinct Types. The modifications are novel taxa-defining homologs, acquired during the process of descent along a phylogenetic lineage, each of which defines a new Type.
– Denton, Michael. Evolution: Still a Theory in Crisis
I repeat, Michael Denton accepts common descent is is not a Creationist. My original thread has been inundated with scoffing and mocking and young earth creationism, all of which are far removed from the subject matter of Denton’s latest book. Trying again.
There is a tree of life. There is no doubt that all extant life forms are related and descended from a primeval ancestral form at the base of the tree. But there is no evidence to support the Darwinian claim that the tree is a functional continuum where it is possible to move from the base of the trunk to all the most peripheral branches in tiny incremental adaptive steps. On the contrary, all of the evidence as reviewed in these first six chapters implies that nature is clearly a discontinuum. The tree is a discontinuous system of distinct Types characterized by sudden and saltational transitions and sudden origins of taxa-defining novelties and homologs, exactly as I claimed in Evolution thirty years ago. The claim has weathered well!
The grand river of life that has flowed on earth over the past four billion years has clearly not meandered slowly and steadily across some flat and featureless landscape, but tumbled constantly through a rugged landscape over endless cataracts and rapids. No matter how unfashionable, no matter how at odds with current thinking in evolutionary biology, there is no empirical evidence for believing that organic nature is any less discontinuous than the inorganic realm. There is not the slightest reason for believing that the major homologs were achieved gradually via functional continuums. It is only the a priori demands of Darwinian causation that have imposed continuity on a basically discontinuous reality.
No matter how “unacceptable,” the notion that the organic world consists of a finite set of distinct Types, which have been successively actualized during the evolutionary history of life on earth, satisfies the facts far better that its Darwinian rival.
In these first six chapters, I have presented my reasons for viewing the biological realm as a discontinuum of isolated Types and pointed out that many of the Type-defining homologs give no indication of being adaptive. I have argued that this empirical picture is incompatible with Darwinism but supportive of typology. Standing on their own, I think the evidence and arguments offered in these first six chapters are sufficient to make a very strong case for my thesis. In the rest of the book, I will provide further evidence for this view by considering in depth the origin of a number of specific novelties. Near the end in Chapter 13 I will also present additional positive evidence for typology.
– Denton, Michael. Evolution: Still a Theory in Crisis.
Did Darwin accept the types or offer an alternative to them?
What would the reality of the types mean for neo-Darwinism?
Mung if mammals are a “type” as Denton claims then whey do we not see mammals appear until over 3 billion years after life was on Earth? Not until around 200 million years ago?
Why do we have so much evidence for the evolution of mammals from the earlier synapsids?
If Denton is so sure of the correctness of his “type” hypothesis why didn’t he submit it to the appropriate scientific journals for publication? Why take the usual Creationist route of self-publishing a popular press book aimed at ignorant laymen?
I know the answer and I suspect you do too.
Saltation was rather thoroughly investigated an rejected in the first 80 years following Origin. It really was seriously considered.
Since we don’t have Denton’s book, perhaps someone who does have it could outline his argument.
I have trouble understanding what Denton was getting at there.
As far as I know, Darwinists hold that evolution involves genetic change. There are finitely many genes. So any genetic change has to be in discrete steps. What does Denton mean by “the Darwinian claim that the tree is a functional continuum”?
Found an online summary:
http://inference-review.com/article/evolution-a-theory-in-crisis-revisited-part-one
I am confused by Denton’s discussion of feather evolution. It’s like he promises an overwhelming argument, then just stops writing without revealing the argument. Best argument I can infer is god of the gaps.
Perhaps the actual argument is in the book.
I read Denton’s online summary. It’s the same old IDiot claptrap “Oooh, this feature is sooo complex! Science doesn’t have every step in its evolution documented therefore evolution could not have done it!”
Looks like another Meyer style Magic Intelligent Designer swooped in from time to time but we won’t say Who (wink wink nudge nudge).
Barry Arrington is reviewing it a chapter at a time at UD. Low interest AFAICT.
I found this discussion of molecular evolution of feathers.
http://bmcevolbiol.biomedcentral.com/articles/10.1186/s12862-014-0249-1
Perhaps Denton’s book explains which step is impossible.
Well, except for all of the lack of discontinuity, and the slight changes throughout the genomes of related organisms.
Why do we even have homologs of the sort that we do? Why not mix and match of form to need, like real designers cause?
We have what we’d expect from largely gradual changes. But oh, we can’t show that some magic causation hasn’t intervened, so, you know, it could have. Never mind any evidence for such fanciful nonsense.
Glen Davidson
Changes of nucleotides to make a new allele can make small changes in the phenotype, or they can make large changes. Either way the alleles have to change frequency in the population. Gradually.
They don’t go instantly to fixation. To imagine that they do is an old idea called saltationism. Which was abandoned anout 1920 as people began understanding the results of the new discipline of population genetics. Which resulted in the Modern Synthesis.
Sounds like Denton is stuck back around 1900.
A ‘natural’ pattern of evolution – mostly small steps; initially species-specific innovations followed by divergence and radiation – would still lead to the somewhat discontinuous pattern we have in fossils and extant genomes. While some kind of tinkering could also contribute to the pattern we have, I don’t see a clear reason to prefer the latter hypothesis. Discontinuity in the data itself is not a solid reason to infer discontinuity in actual history, any more than a gap in a family tree means a complete absence of real individuals, or alien abduction through a faster time zone.
(I accept that certain events – endosymbiosis, eukaryotic sex, genome duplications and rearrangements, large scale HGT events – could be argued as ‘discontinuous’ on the strict-gradualist model. But if people hold a view that ‘Darwinian’ evolution only occurs by point mutation, they hold an erroneous view.)
Technically speaking all mutations, and all changes of gene frequency, are actually discontinuous. For example, in a population of size
, gene frequencies can assume only the discrete values 
, and 
. But these are discontinuous on a very small scale, so we habitually think of the gene frequency scale as continuous, and use continuous mathematics to describe it.
But it is if we see discontinuity on that small a scale, that is no reason to reject normal evolutionary processes.
Based on the quotes we have been given above, Denton seems to be arguing that evolution involves jumping among distinct “types”. At what scale? Individual species are all distinct “types”? Are the the White-Throated Sparrow, the White-Crowned Sparrow, and the Golden-Crowned Sparrow all distinct “types”?
Denton (above) gives away the answer by speaking of the “major homologues”. That means, I suspect, that his discontinuities are at a large scale and that he does not reject natural selection, mutation, migration, and genetic drift as sufficient to explain the evolution of individual species. Or genera, or more.
Denton is quite open about being a saltationist.
It’s a saltation of the gaps argument, throughout the book.
For the life of me I can’t seem to understand what it is Denton thinks the theory of evolution predicts which is presumably different from what we see. Descendants inherit the body plans of their ancestors and are subject to environmental selection… and then what? Why should this produce outcomes different from what we see? Please enlighten me.
Let’s go back to Tiktaalik, and pretend that either Structuralism or “the theory in crisis” is true. What’s going to evolve on structuralism, and what’s going to evolve on “the theory in crisis”? Predict something for me from first principles that clearly delineates structuralism from the theory in crisis.
Sal seems to think there is a first individual of a new species.
But not in the sense that Joe was using the word:
They don’t go instantly to fixation. To imagine that they do is an old idea called saltationism.
Please guys, you may disagree with Denton, but try to do better.
Denton accepts the reality of Darwinian gradualism including natural/cumulative selection but argues that mutation/cumulative selection alone are insufficient to explain the evidence. his arguments is against a full-blown functionalism which rejects structuralism.
The levels at which the type-defining homologs exist varies, so he would not say it is class level and above only or any thing of that sort. He gives examples within classes.
At no point does Denton argue for anything non-natural to explain the “saltations.” They are physical and have a natural cause. It’s just not one explainable by functionalist accounts.
Hi Neil.
According to the opposing paradigm, often referred to as functionalism, the main or sole fundamental organizing principle of biology is adaptation. On this view, the main Type-defining homologs (pentadactyl limb, etc.) are adaptations built by cumulative selection during the course of evolution to serve various adaptive ends.
Denton, Michael (2016-01-26). Evolution: Still a Theory in Crisis (Kindle Locations 243-245). Discovery Institute Press. Kindle Edition.
The makers of the synthesis desired to show that all evolutionary change—not just at the microevolutionary level—could be accounted for by the cumulative selection of small adaptive changes. In other words, macroevolution is a mere extension of microevolution.
Denton, Michael (2016-01-26). Evolution: Still a Theory in Crisis (Kindle Locations 276-278). Discovery Institute Press. Kindle Edition.
This is a mistaken view of what Denton argues. If you are going to pretend to critique Denton you ought to at least read the book. Denton doesn’t claim any step is impossible.
Summary The origin of the various feather novelties and the developmental processes that actualize them are enigmatic in classic Darwinian terms. Prum and Brush conclude:
Denton, Michael (2016-01-26). Evolution: Still a Theory in Crisis (Kindle Locations 2919-2923). Discovery Institute Press. Kindle Edition.
On any common-sense assessment of the evidence now available, it would seem that the feather arose (like the limb Bauplan) because of internal causal factors and not to serve functional constraints.
Denton, Michael (2016-01-26). Evolution: Still a Theory in Crisis (Kindle Locations 2929-2930). Discovery Institute Press. Kindle Edition.
Nice find petrushka. People who don’t have the book ought to read that.
Exactly what the eff does this mean?
The need for function does not cause features to arise. Nothing in mainstream biology addresses a cause for new genetic sequences. At least not any cause that anticipates need or responds to need.
Even Shapiro says that.
Mung,
I fail to see the point.
You act as if you are answering my question. But all you do is provide a quote from Denton (which I had already seen), a quote which utterly fails to answer the question.
The modern synthesis claims that evolution moves is small discrete (gene-sized) jumps. Calling that “continuous” is acceptable, because we do sometimes use “continuous” in that fashion. But Denton said “continuum”, and a continuum excludes small discrete jumps.
Does Denton address the fact that the genes enabling body plans and features arose in bacteria, long before there were any multi-celled organisms able to sprout wings and eyeballs?
Does he consider that once these genes existed — for reasons having nothing to do with bodies — they constrained development of body feature?
Neil, your obtuseness never ceases to amaze me.
Here, I cherry-picked this for you:
If you want to argue that “a continuum excludes small discrete jumps” you go right ahead.
If Denton does not envision any jumps larger than those we already know about , there’s no problem.
But no originality, either.
But his discussion of feather evolution, although vacuous, leaves one with the impression that he doubts that feathers arose by gene duplication and gradual variation.
Mallet sees continuum of differences in nature
That’s cool, but there’s nothing new in it, if you’ve followed the discussion on this site, or read anything by Gould or Mayr.
This is my take from the discussion also. Yes, of course there are discontinuities. At the genotype level these are small incremental changes, though at the phenotype level they can be quite striking (I’m thinking of corn here).
But how is evolution a theory in crisis if it nicely explains everything Denton seems to have trouble with? The crisis seems to be Denton’s own.
Argument by cherry picked dictionary definition, quoted but without citation.
Denton says that this was a claim by Darwinists. Denton is being dishonest, presumably for rhetorical purposes.
Mung,
Denton:
That’s not what Prum & Brush conclude, despite their being quoted as the authorities. It seems strange to quote them on failure of ‘neo-Darwinian’ approaches’, but fail to add that their conclusion is not to discard adaptation altogether, but instead to urge an ‘evo-devo’ approach. Each novelty is still likely adaptive, rather than driven by vague ‘internal causal factors’ with no clear mechanism for their increase or maintenance in the population.
An ever better example is the Hawaiian Silversword alliance. This refers to an adaptive radiation of over 50 species from a single plant of the sunflower family that colonized the Hawaiian islands around 5 million years ago. The morphology of the different species is extremely diverse, composed of trees, shrubs, subshrubs, mat-plants, cushion plants, rosette plants, and liana.
Adaptive Radiation and Macroevolution in the Hawaiian Silverswords
The answer is evolution isn’t in crisis. Denton looks like another IDiot looking to make a quick buck off the True Believer rubes.
Island populations might be an interesting source of bottlenecked populations.
I recall asking Sal about why there were so many ,thriving populations that had to be inbred, and not dying out from genetic deterioration.
There are quite a few new populations from historical times. It might be fun to check divergence in the rabbit population in Australia.
Denton agrees.
The origin of the feather is as puzzling as the origin of the tetrapod limb or the enucleate red cell. To be sure, unlike the enucleate red cell or the “primal pattern” of the tetrapod limb, the feather is clearly an adaptive form, useful for flight, for insulation, for sexual display, etc. Further, no one doubts the utility of the stages that led from the simple follicle through the plumaceous feather to the closed pennaceous contour feathers of modern birds. Yet this taxon-defining novelty appears to be just as inexplicable in Darwinian terms. Cumulative selection cannot even begin to account for the origin of the series of novelties that make up the avian feather.
– Denton, Michael. Evolution: Still a Theory in Crisis
Although the origin of the feather occurred via a succession of novelties (see Figure 9-2), the new evo-devo picture provides not the slightest evidence that any of the novelties leading to the feather were actualized by cumulative selection.
– Denton, Michael. Evolution: Still a Theory in Crisis.
In the original post above Mung quoted Denton (It is not exactly demarcated, but I think it is a quote) as saying:
Is that an adaptive landscape? Or just a geographical analogy? If it is an adaptive landscape then Denton comes perilously close to the Modern Synthesis.
What does “actualized” mean, in context?
It seems to mean that a “succession of novelties” is NOT a “cumulative selection”. I guess it was just a series of accidents, each of which happened to work better than the last just at random. ultimately blundering upon the modern feather. So something is “actualized” when it simply comes to pass, and no conclusions about cause can be drawn from its history.
How are those two statements by Denton not merely arguments from ignorance and personal incredulity?
Joe F. My reading is that it is a geographical analogy.as indicated by the following sentence:
No matter how unfashionable, no matter how at odds with current thinking in evolutionary biology, there is no empirical evidence for believing that organic nature is any less discontinuous than the inorganic realm.
Selection does not account for the appearance of anything.
Does Denton address Wagner’s “Arrival of the Fittest”?
No, he is plainly saying that each individual novelty was not the result of cumulative selection. Not that the individual novelties taken one after the other did not accumulate.
No, but he references his The Origins of Evolutionary Innovations.
What does that mean, in context? Is he really saying that feathers are not an accumulation of novelties, each of which occurred independently?
Ah, I think I understand. Each individual added novelty might be useful, and it might even enhance the reproductive success of its possessor, but this isn’t selection, oh no, this is simply a succession of accidents. Is that what he’s saying?
Denton writes Cumulative selection cannot even begin to account for the origin of the series of novelties that make up the avian feather. Now, I interpret this to mean that selection did not ORIGINATE the novelties, and no evolutionary biologist would argue with that. What selection did was to conserve those novelties that were helpful, and discard those that were not.
So what do YOU think he’s trying to say?
Is he for it or again it?
Did anybody think otherwise?
Surely individual novelties are the result of random mutation
I suspect Denton would say, but ah ha! How do you explain the just in time, coordinated delivery of just the right mutations in just the right sequence.
Bread goes down; toast comes up. You can’t explain that.
Am I not right?
Absolutely. If these mutations weren’t timed and coordinated just right, we’d never have feathers. That cannot be random, how could it?
Yes, that’s likely.
Joe Smith won the lottery. How do you explain the individual coordinated circumstances that just happened at the right time for Joe to have won?
It’s the lottery fallacy. Gould was right to point to the role of contingency. But you cannot jump from their to saltation, as Denton apparently wants to do.
Denton has a long section on angiosperms. He sees the need for saltation to explain how they quickly took over. But if we look at the rapid spread of the zika virus in S. America, we see something similar. Rapid spread after a small change is not at all surprising.