In “Remember that Darwin-eating plant? Now threatening to eat Nick Matzke … ” (September 3, 2011), we posted geneticist Wolf-Ekkehard Loennig’s objections to Berkeley evolutionary biologist Nick Matzke’s assurances that Darwin explains carnivorous plants. Indeed, Dr. Loennig betrays a hint of impatience, remarking,
Matzke still doesn’t seem to have carefully studied my extensive paper yet, but he is still complaining that others know nothing on that topic and keeps on talking some nonsense promoting some half-baked ideas.
Nick Matzke replied, Eh? The following is what I said before.
Amongst anyone who knows anything about this topic, it is well-known that the general pattern is that carnivorous plants live in nutrient-poor environments, and use the insect to supplement their nutrient diet. Sometimes the limiting nutrient might not be nitrogren, it might be phosphorous or something else. Aquatic Utricularia typically live in oligotrophic freshwater environments, but they might even be getting a carbon advantage in addition to nutrients. Doesn’t matter to the basic story. Sometimes the carnivorous plants can grow apparently fine without eating any insects, but — and Darwin was the first to do experiments to support this, IIRC — plants that get insects produce more seeds (which require big nutrient investments), which is a rather obvious reproductive advantage. So this doesn’t change the basic story either. Another complexity is that other, non-carnivorous plants can grow in carnivorous plant habitat — but it looks like the carnivorous plants have a growth advantage after the environment is disturbed, e.g. by fire, i.e. CPs are early successional plants, without regular disturbance they eventually get shaded out by slower-growing competitors. Still doesn’t change the basic story.
Nothing you have posted even contradicts it. Saying that carnivorous plants tend to be found in nutrient-poor environments is not the same thing as saying that everything that lives in nutrient-poor habitats ought to be carnivorous. There are various ways to survive in nutrient-poor habitats. One is being carnivorous. Another is being slow-growing.
Do you deny that there are experiments that show that fed carnivorous plants tend to produce more seeds? Do you deny that carnivorous plants tend to be found in nutrient-poor habitats?
If you can’t even admit these basic points, why should scientists take you seriously?
And — under an ID hypothesis, what is carnivory for?? You don’t get to say “it’s a design for improving the plant’s nutrition”, not if you sit here bashing that idea apparently because you will bash anything that Darwin came up with, right or wrong.
UD News is unaware that Darwin came up with a theory of carnivorous plants, but that’s excusable, because neither was Darwin, it seems. Nor Wallace.
But now, over to Dr. Loennig, to reply:
1) Concerning adaptation an illustration: Rowboats are adapted to water – so all rowboats are derived from other boats or land vehicles by variation and selection without any design at all?Does such a scenario not presuppose the very thing to be explained? Does the addition that there are many other kinds of boats and ships without rudders but with sails or motors (or in combination of all three) all adapted to the same environment (water) prove or weaken the no-design-hypothesis?2) Application to carnivores: According to the synthetic theory (neo-Darwinism) there is no link between a specific environment and the generation of correspondingly functional DNA-sequences. Is it scientifically correct and fruitful to simply take it for granted that random variation has accomplished it in all cases of living beings (including the carnivores) without asking the question whether it really can and has in fact done so?3) Most carnivorous plant researchers – all evolutionary biologists sensu lato – have noted (often independently of each other) some basic problems associated with the origin of many of these species for more than 100 years now:Charles Kingsley (1871), Karl Goebel (1928-33), Francis E. Lloyd (1942/2007), T. Schmucker und G. Linnemann (1959), A. Slack (1986, 2001), Pierre Jolivet (1987), Peter Taylor (1989/1994), A. Remane, V. Storch und U. Welsch (1989), D’Amato (1998, p. XIX: “…how these species actually evolved is still the deepest of mysteries“), J. und P. Pietropaolo (1986/2001), F. Rivadavia, K. Kondo, M. Kato and M. Hasebe (2003, p. 123: “…the evolution of leaves with trap systems from noncarnivorous ones is mysterious, and there are no widely accepted hypotheses“), Lecoufle (2006), Rice (2006), Fleischmann (2010, p. 1143: “…the evolutionary origins of the Utricularia trap remain incompletely understood.” For the details see again http://www.weloennig.de/Utricularia2010.pdf 4) If these evolutionary researchers are correct – is Nick Matzke’s message – that all origin problems are (or at least will be) solved within the present evolutionary frameworkand that there are no scientific reasons to ever doubt it – not perhaps a bit premature?5) Why does Nick not answer Nachtwey’s questions on the evolution of Utricularia’s trap? Suction in half a millisecond: How did the trap become watertight and functional as a suction trap with all its synorganized anatomical and physiological details by a series of random ‘micromutations’ with slight or even invisible effects on the phenotype (Mayr)?6) My list of carnivorous plants not occurring in nutrient deficient environments is constantly growing. None of the 7 Utricularia species of Middle Europe occurs at extremely nutrient deficient biotopes. In fact, 6 of them are regularly to be found almost only in mesotrophic to eutrophic environments and the 7th can also be met in mesotrophic localities. (Matzke’s statement “Aquatic Utricularia typically live in oligotrophic freshwater environments” is untrue in all these cases.) As to Pinguicula in general with almost 100 species: “extremely nutrient poor localities are avoided” (Caspar).So what about adaptation per se as quoted above in such cases? More details in the link already mentioned.7) Peer review. The paper by Lönnig and Becker (2004/2007) on Carnivorous Plants is peer reviewed.8 ) Although N. Matzke uses expressions like “silly”, “scientists detest creationism/ID”, “your complete anti-intellectualism” etc. – in a second thought I would have avoided language like “nonsense” and “half-baked”, for it doesn’t help to understand each other.Much, really much more could be said about Nick’s comments – but in fact most of them have already been answered at length in http://www.weloennig.de/Utricularia2010.pdf UD News takes this view: What scientists consider a problem and what they consider a solution depends on their prior commitments. Nick Matzke knows that Darwinism is true, and that evidence-based doubt is an assault on science itself. W.-E. Lonnig is looking at a life form whose current state is clearly not due to Darwinian mechanisms – and whose circumstances are misstated in order to protect the full explanatory adequacy of Darwin’s theory. So he keeps arguing the facts.
Finally, readers must decide for themselves whether Darwin or facts is more important.
See also: Remember that Darwin-eating plant? Now threatening to eat Nick Matzke …
Carnivorous plants: After eating Darwin, they couldn’t resist further culinary adventures
The plants that eat vertebrate animals
Carnivorous plants: The 200-year headache.