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DI is attacking PS’s @evograd. Let’s see what kind of response PS can put together that obliterates Bechly’s rant.

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Oh my. The article’s last sentence links a Darwin’s Doubt book review (which is not recommended reading on a full stomach.)

Here let me separate from all the posturing and spin and summarize the main complaint of Bechly :

I found someone who disagrees with @evograd.

That’s it, that’s what that article amounts to.

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It’s quite a strange article.

Here are two very interesting updates to my recent articles at Evolution News on alleged Ediacaran animals and the Cambrian Explosion.

When I read this first sentence, I assumed the article would be about some recent papers that had been published that added to the discussion of the topics of his previous articles (both from 2018). He’s writing in 2021, after all. Turns out the two updates are a response to a comment I made here on PS in 2018 (a month after his article came out in September), and a paper that came out in 2018. Why Bechly is responding 3 years later is a bit beyond me, but he seems to think it’s important.

In my article (Bechly 2018b) about the iconic and enigmatic Ediacaran organism Dickinsonia , I showed why in spite of new biomarker evidence presented by Bobrovskiy et al. (2018), Dickinsonia is unlikely to be an animal. Such evidence-based skepticism is of course not greatly appreciated in Darwinist circles and provoked a response.
At the Peaceful Science forum, an anonymous atheist and self-professed blogging graduate student (evograd 2018), who obviously lacks sufficient expertise as well as some reading comprehension, criticized my article with a red herring quibble about two of six references that Bobrovskiy et al. quoted (which I actually never disputed), while ignoring all real arguments. Just read my article and compare it with his criticism to decide for yourself if it has any merit. Anyway, this young know-it-all then triumphantly proclaimed:

The relevant context here is that the authors were specifically testing the animal affinity for Dickinsonia against other hypotheses of a lichen fungi affinity or a giant protist affinity. By ruling out lichen fungi and giant protist affinities, the only remaining plausible option is that Dickinsonia is an animal.

First, can we just appreciate the fact that Bechly decided to write half an article responding to a short, innocuous comment made 3 years prior by an anonymous grad student on a pretty niche forum? Either I really got under his skin for some reason or he’s scraping the bottom of the barrel for content to write about. Anyway, on with the content…

Bechly says I criticized his article “with a red herring quibble about two of six references that Bobrovskiy et al. quoted (which I actually never disputed), while ignoring all real arguments.” My comment was obviously not intended to be a thoughout critque of Bechly’s entire article - I’m not an expert on Ediacaran animals, so I just commented on something I noticed in the article that seemed incorrect. In a sense, then, his charge that I “ignored all real arguments” is true, but that doesn’t detract from the comment I made. The “red herring quibble about references” isn’t a red herring at all, it’s a substantive criticism of Bechly’s article.

Specifically, I had an issue with the section of Bechly’s article titled “Incomplete Homework”, where he criticized the authors of a study for “not doing their homework” on the subject of cholesterols in organisms other than animals. In short, the case he made went like this: “The authors claim Dickinsonia is an animal becuase they identified cholesterol in it and they say cholesterol is only found in animals, but look at all these papers that show non-animals producing cholesterol! The authors clearly didn’t do their homework!”

The problem with this argument, as I pointed out in my comment in 2018, is that the authors actually discussed the subject of non-animal cholesterols in their paper, citing some of the very same papers that Bechly did to try and prove their ignorance! I quoted the following passage from the paper to show this:

Using the remarkable steroid patterns of the fossils, it is possible to test the position of dickinsoniids on the phylogenetic tree. Lichen-forming fungi only produce ergosteroids, and even in those that host symbiotic algae, ergosteroids remain the major sterols (29, 30). Dickinsonia contained no or a maximum of only 0.23% ergosteroids, conclusively refuting the lichen hypothesis (7). The groups of rhizarian protists that include gigantic representatives (Gromiidae, Xenophyophorea, and other Foraminifera) and their retarian relatives all produce a complex mixture of sterols, with cholesteroids comprising 10.3 to 78.2% of the mixture, ergosteroids 4.9 to 43.0%, and stigmasteroids 7.2 to 60.1% (table S4). Moreover, rhizarian protists may produce C30 sterols (24-n-propylcholesteroids) that can form a notable (up to ~20%) proportion of their total sterol content (31). By contrast, in most Dickinsonia and Andiva extracts, C30 steroids were below detection limits. Thus, the steroid composition of dickinsoniids is markedly distinct from steroid distributions observed in Rhizaria, rendering a protozoan affinity of these fossils extremely unlikely. All animals—with rare exceptions, such as some demosponges and bivalve molluscs—are characterized by exclusive production of C27 sterols (32, 33). The closest relatives of metazoans, Choanoflagellatea and Filasterea, produce 90 to 100% and 84 to 100% of cholesterol, respectively, and contain up to 16% ergosteroids (34–36). Although the sterol composition of some choanoflagellates and filastereans falls within the range observed for Dickinsonia and Andiva, they are unlikely precursor candidates because these groups are only ever represented by microscopic organisms, leaving a stem- or crown-group metazoan affinity as the only plausible phylogenetic position for Dickinsonia and its morphological relatives.

In order to put that quote in context so it made more sense to the readers, I said the following directly underneath it in my 2018 comment:

The relevant context here is that the authors were specifically testing the animal affinity for Dickinsonia against other hypotheses of a lichen fungi affinity or a giant protist affinity. By ruling out lichen fungi and giant protist affinities, the only remaining plausible option is that Dickinsonia is an animal. The only other option is that the cholesterols are some kind of contaminants from other organisms.

I was summarising the argument the authors made in the quoted passage from the paper to make it easier to understand how Bechly was misrepresenting them. He was claiming that the authors were wholly unaware of the existence of non-animal cholesterol, and that was how they concluded that Dickinsonia must be an animal. The passage shows that their reasoning is much more nuanced - they recognise that other organisms produce cholesterols but argue that Dickinsonia couldn’t be a member of these other groups (e.g. rhizarian protists) for other reasons (e.g. Dickinsonia had a radically different steroid composition compared to rhizarian protists).

Bechly entirely ignores my criticism of him strawmanning or misunderstanding the authors on this point (he dismisses it as a “red herring”), and instead chooses to focus on my summary of the author’s argument, saying I’m a “young know-it-all” who made a “triumphant proclamation”. His response to my summary is:

The problem is, this is simply false. Do not take my word for it, but that of paleontologist Professor Gregory Retallack, who is a renowned specialist on Ediacaran biota. In response to the article by Bobrovskiy et al. he wrote a comment to the journal Science (Retallack 2018) titled “Dickinsonia steroids not unique to animals.” In this comment Retallack explains that the biomarkers found in Dickinsonia fossils are fully compatible with an affinity to lichenized glomeromycotan fungi. If there are even such alternative candidates among living organisms, this may well have been even more the case in the extinct Vendobionta, which have been proposed as an independent Ediacaran kingdom of life by Seilacher (1992). The very alien body plan of Dickinsonia with glide symmetry definitely supports such a Vendobionta hypothesis rather than an animal affinity (McMenamin 1998/2000).

Again, this feels like a point that might have been worth making back in 2018, and seems strange to direct towards me specifically, 3 years later. Once again, the point of my 2018 comment wasn’t that the conclusion of the original authors was unassailable, but simply that Bechly had misrepresented them. That said, the original authors actually promptly responded to both of Retallack’s criticisms, pointing out, for example, that contrary to what he claimed, Dickinsonia is unliklely to have an affinity with Glomeromycota because the latter doesn’t actually produce cholesterol. To a non-expert like me, this response seems adequate to dismiss Retallack’s criticisms, so Bechly seems not to have a leg to stand on here either.

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What’s to obliterate? It’s mostly outrage that a graduate student would dare to challenge him. He distorts the paper he cites on the Ediacaran-Cambrian transition in Namibia, notably in ignoring the recent evidence that Namacalathus is a lophotrochozoan, and in misrepresenting the gradual increase in trace fossils as the complete Cambrian explosion. The reference to Darwin’s Doubt is comical. Doubtless @evograd will have a response.

Is Bechly a YEC or OEC?

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Either way, it’s less work than actually doing science.

Refraining from commenting on areas in which one lacks expertise does not appear to be an option ever considered at the DI.

Since he describes you as anonymous and a graduate student, how can he possibly know that you are young, given that youth AFAIK has never been a requirement for entering graduate school?

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Thanks for the explanation. I find this is par for the course; when the DI criticizes things I’ve written, it always starts by mischaracterizing what I’ve said and then spins off on some strange tangent, usually completely nonresponsive to the actual critique. Judging from your post here, I would say that they must have an official in-house style manual to that effect.

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True, but I would say it’s a fair (and in this case, correct) guess - most graduate students tend to be in their 20s.

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This is what hyperbole looks like.

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That sounds a lot like the quips that were directed towards Nick Matzke way back when. Nick also had a knack for confounding the degreed scholars that are the vanguard of the ID community.

If the present story plays out as in the past, your future is bright, @evograd. In the years since they assailed Nick, the ID vanguard have been reduced to churning out repetitious, vapid, self-citing drivel. Behe, Axe, Meyer, et al. - nary a whiff of a credible scientific or even scholarly work in the years since they first attacked Nick.

Nick, OTOH, has been excellent headway on a most interesting and important problem, doing exactly what the ID vanguard has been insisting can’t be done, and should not be done.

Nicely done, @evograd.

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Yes, but it wasn’t labeled as a guess–I was just pointing it out because it smells of desperation.

Thou I am honored, I’m pretty sure this is the comment @Art meant to link. :grinning:

Oops. Thanks for the heads up. Just to confuse matters more, I fixed my link. But yours is a better one.

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As per Gunter Bechly himself

I see neither any scientific nor compelling other reasons to dispute the conventional dating of the age of the universe and Earth, or the conventional explanations for the origin of the geological column and the fossil record. I also consider so-called Flood Geology of Young Earth Creationists as a totally failed endeavor.

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Wow. He’s stranger than a YEC. Did you read his description of how evolution works? He’s got the full Chopra.

Yes. It’s hard for me to escape the conclusion that they are not in the least interested of actually countering arguments, so much convincing the paying customers in the peanut gallery that the arguments have been countered. It works because those paying customers are highly unlikely to understand the arguments in the rare instances that they are even read. Evidence of this abounds in this very forum.

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Precisely. A lot of the time the disconnect between what they say in rebuttal and what they are supposedly rebutting is quite extreme, but to know that, you’d need to pay attention and understand the issues. Their intended audience doesn’t pay a lot of attention and doesn’t understand the issues, so, Bingo!

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Hey Günter. I’d like to see your thoughts on this one:

And just so you know, you can’t cite the 2016 paper that shows some trace fossils are due to currents and mats. I personally contacted the author of that paper and he said his findings Cant account for these fossils.

This one too:

https://royalsocietypublishing.org/doi/10.1098/rsos.172250

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