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Carnivorous plants eat Darwinists

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File:Pitcher Plant, Ontario.jpg
pitcher plant, in business/D. Gordon E. Robertson

University of Bonn geneticist Wolf-Ekkehard Lönnig will soon have a new book out, on the 200-year-old headache that carnivorous plants pose for Darwinism. Briefly, how does a plant evolve in slow, Darwinian steps, toward making insects part of its normal diet? Like the pitcher plant, for example. A it’s the floral emblem of the Canadian province of Newfoundland, we’ll let the government there explain:

The pitcher plant gets its nourishment from insects that are trapped and drown in a pool of water at the base of its tubular leaves. These plants, with their wine and green flowers, are found on bogs and marshes around the province.

If you are not a bug, you maybe never even noticed. The pitcher is one of the few northern carnivorous plants; its unusual food choice enables it to live in poor soil.

Here’s Granville Sewell’s take:

In every family of the plant and animal kingdoms there are species whose sudden appearances and whose irreducibly complex features pose problems for neo-Darwinism. But certain carnivorous plants pose these problems in such a spectacular way that they are a focal point of the Darwinism debate, ever since Alfred Wallace warned Darwin about the problems posed by Utricularia, saying “I feel sure they will be seized on as inexplicable by Natural Selection” and implored him to address these difficulties in a future edition of his book “On the Origin of Species.”

Darwin never did, but some more recent authors have proposed various contradictory gradualistic and saltationist explanations for this spectacular example of irreducible complexity.

W.-E. Loennig answers these authors with great luxury of detail, and shows that “after more than 135 years of further research, Darwinism today can no more satisfactorily answer these questions than Darwin could. And the difficulties have increased.”

Wolf-Ekkehard Lönnig

Also, here’s Lönnig’s “The Evolution of the Long-Necked Giraffe” translated into English by Sewell:

Ulrich Kutschera made the following statement regarding the origin of the giraffe, on 29 November 2005 in 3SAT (a German TV channel): “…the evolution of the long-necked giraffe can be reconstructed from fossils.” According to today’s best giraffe researchers, all fossil links that could show us the gradual evolution of the long-necked giraffe from the short-necked giraffe are missing, apart from the insufficiently answered question of causes. More.

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"The IDer has a unusual dislike of insects?" That can't be right - we know from Haldane that God has "an inordinate fondness for beetles"! Grunty
There are a lot of documented, tested and/or plausible steps for the origin of the Venus Flytrap. Are you seriously going to argue that, OK, the Venus Flytrap evolved, but the Utricularia trap must have been designed? And -- why in the world would an IDer bother? The IDer is feeling sorry for the poor plants living in rare nutrient-poor bogs? The IDer has a unusual dislike of insects? NickMatzke_UD
But of course, there is no evidence that a "designer" did it. Strangely, even if you think the "designer" did it, you still don't have a mechanism for how the design was done. Grunty
As Someone once said: "By their fruit you shall know them." Ilion
Only if a designer didn't do it. You take "fruitful" and I'll take "accurate." How fruitful is being wrong? Apparently fruitful = imaginative. Some science. ScottAndrews
Nick, 1- Intelligent Design is not anti-evolution. 2- How can we test the claim that snap-traps "evolved" from glue-traps via accumulations of genetic accidents? For example can biologists go into a lab, take glue-trap seeds, mutate them at their direction and get a snap-trap to develop after X generations? Or perhaps the other way- snap to glue? Joseph
It's a lot more fruitful than just saying a Designer did it. Grunty
Nick, Your far-fectched gradualist explanation for how glue-traps might have evolved into snap traps is not at all convincing, but in any case, Loennig's book is about neither, it is about suction traps. For the reader's benefit, here is a short overview of the aquatic bladderwart trap: "These traps have trigger hairs attached to a valve-like door which normally keeps the trap tightly closed. The sides of the trap are compressed under tension, but when a small form of animal life touches one of the trigger hairs the valve opens, the bladder suddenly expands, and the animal is sucked into the trap. The door closes at once, and in about 20 minutes the trap is set ready for another victim." I am not a biologist, so I will not attempt to further argue the details, I will simply refer readers to Loennig's book (not out yet, but I linked a recent version above). But it is obvious that any gradualist explanation for such traps would have to be very far-fetched. And gradualist doesn't mean two or three (imagined or real) useful intermediate steps, it means hundreds or thousands of useful intermediate steps. Granville Sewell
An interesting article. It elaborated on the differences between snap-trap and flypaper plants, and in each case referred to the difference as an "evolution" or a "transition." Apparently when two things are similar we are to reflexively assume that the differences resulted from random mutation and selection. This is another case of perfectly circular reasoning. RM+NS is offered as the explanation for the similarities between the two plants. And the evidence for RM+NS acting in this manner is, again, the two plants. ScottAndrews
I would be more impressed with Loennig's research if he admitted that (1) Darwin himself proposed that the snap-trap of Dionaea (Venus Flytrap) was derived from a slowly-closing glue trap like that of Drosera (sundews) (2) exactly this set of relationships was found when DNA sequencing allowed phylogenetic analysis. The snap-traps nest within a large clade of glue-traps. (3) Morphological studies have also confirmed homology between the tentacles of Drosera and the "trigger hairs" and spikes of Dionaea. (4) The Drosera genus, just within that genus, has variability in closing times ranging from days to seconds. (5) The "rapid" motion of Dionaea is actually just due to the leaf changing from concave to convex. This is initiated by a slow movement that is the same as the Drosera slow movement. (6) Even IDists/creationists admit that features, like glue, can be lost (7) There is even a detailed published version of this model, with tests:
Evolving Darwin's 'most wonderful' plant: ecological steps to a snap-trap Thomas C. Gibson1 and Donald M. Waller2 New Phytologist (2009) doi: 10.1111/j.1469-8137.2009.02935.x Among carnivorous plants, Darwin was particularly fascinated by the speed and sensitivity of snap-traps in Dionaea and Aldrovanda. Recent molecular work confirms Darwin's conjecture that these monotypic taxa are sister to Drosera, meaning that snap-traps evolved from a 'flypaper' trap. Transitions include tentacles being modified into trigger hairs and marginal 'teeth', the loss of sticky tentacles, depressed digestive glands, and rapid leaf movement. Pre-adaptations are known for all these traits in Drosera yet snap-traps only evolved once. We hypothesize that selection to catch and retain large insects favored the evolution of elongate leaves and snap-tentacles in Drosera and snap-traps. Although sticky traps efficiently capture small prey, they allow larger prey to escape and may lose nutrients. Dionaea's snap-trap efficiently captures and processes larger prey providing higher, but variable, rewards. We develop a size-selective model and parametrize it with field data to demonstrate how selection to capture larger prey strongly favors snap-traps. As prey become larger, they also become rarer and gain the power to rip leaves, causing returns to larger snap-traps to plateau. We propose testing these hypotheses with specific field data and Darwinlike experiments. The complexity of snap-traps, competition with pitfall traps, and their association with ephemeral habitats all help to explain why this curious adaptation only evolved once.
Nick, There isn't anything in either of your links that demonstrates genetic accidents can accumulate in such a way as to give rise to these organisms. All this proves is that you will believe anything as long as it goes against design. Joseph
Nick, Loennig worked for 30 years at the Max Planck Institute for Plant Breeding in Koln, if you'll look at either his 274 treatise on Utricularia or his Encyclopedia of Life Sciences articles I linked in comment #2, you'd see how unfair it is for you to dismiss his opinions by saying "why is it so hard for folks to do a little research on the evolution of these systems." Granville Sewell
The Venus Flytrap openly admits that the explanation is purely hypothetical. I know it's easier to imagine something and call the problem solved, but isn't it really a bit premature? Besides, it's laughable. How does one man with no architectural knowledge build the Empire State Building? Easy - he starts with an Empire State Building with scaffolds and knocks them down. ScottAndrews
Nick, you might be interested to know that pitcher plants (Sarracenia purpurea) are invasive pests on bogs in Ireland and Britain. An evolutionary success story, but an ecological problem! Prof. FX Gumby
Of course, at some times but not others, Behe has ruled out macroscopic systems from being IC. But whatevs. Why is it so hard for folks to do a little research on the evolution of these systems? Darwin wrote a whole book about carnivorous plants, and hit on the basic solution to the origin of the Venus Flytrap -- scaffolding: http://www.talkdesign.org/faqs/icdmyst/ICDmyst.html#venus ...a hypothesis which has been confirmed in multiple ways since then. As for Utricularia: http://www.bacps.org/2005April.html NickMatzke_UD
The book is in German ( here is an early version) but here is an article in English that Loennig co-authored, which makes some very interesting points on this topic, see "The Origin of the Carnivorous Plants" beginning on p5. Granville Sewell
...but some more recent authors have proposed various contradictory gradualistic and saltationist explanations for this spectacular example of irreducible complexity.
The same theory generates contradictory explanations for the same phenomenon? No wonder it's such a powerful theory. Mung

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