More Excuses for Cambrian Non-Evolution

It appears to me that perhaps the best way forward here is for you to get the book, read the book, and then point out the cases of evolution outlined in it that are non-Darwinian. I didn’t see any. Neither, as I take if from his comments, did John.

Joshua has declared Darwinism dead. I say not so fast.

If I showed you a map of the South Pacific and it didn’t show Europe would you think the map was trying to claim that Europe doesn’t exist?

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Do bad analogies have no end?

Do you understand why a book that only discusses positive adaptations is in no way trying to claim that only positive adaptations occur? Yes/no?

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Yes. I’ve never claimed that the book is a basis for thinking that only positive adaptations occur. Where on earth did you come up with that? Do you just ignore what I write about neutral evolution and random genetic drift?

Then why did you describe it as Darwinian? Darwinian evolution is where change is either a product of positive or negative selection with no neutral drift.

Oh, by the way, this is what Losos said in his book:

That is non-Darwinian. That is the modern mainstream theory of evolution.

The real question is why you need to use the word “Darwinian” so badly. Why is this?

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@Mung

At the very least, Darwinism doesnt accommodate God’s guidance. So at a minimum, Joshua is describing the irrelevance of Darwinism from a THEOLOGICAL perspective.

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Do you know what he meant by that? I don’t think you do. Stop trying to start a fight. I don’t think Swamidass would have any problem with Losos.

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No, I don’t believe that’s what he’s doing at all. It would be nice if @swamidass would clarify, but in case he doesn’t show up, I think he’s just talking about the integration of neutral and near-neutral theory into evolutionary biology.

@John_Harshman

Man, are you impatient. He is responding to questions from all over the internet… he has no staff… and he is “disturbing the industry” from almost every angle.

And you want him to prioritize a question he has already answered many times?

At the risk of misinterpreting him, unless he specifies otherwise, or if the context doesnt already indicate:

if he uses the word Evolution, he means it the way Patrick means it: as the modern synthesis of Darwinism;

If he uses the term “DarwinIST” it usually means the same as above;

If he uses “DarwinISM” it usually means Darwin’s version of Evolution;

And SOMETIMES, when speaks of Evolution in a Christian sense, he is allowing for God’s guidance of Evolutionary results, which is not conventionally included with the term Evolution or Darwinism.

@swamidass

Feel free to edit my text as necessary… just let me know… so i can update my understanding of your terminology!

Please use lower case “e” . Use evolution to describe the entire 2018 understanding of in all evolutionary science and related disciplines. Thanks

There is no such person who is a Darwinist. And Darwinism is not part of evolutionary science. And what is evolution in a Christian sense? As there is no difference between evolution in a Jewish sense, a Mormon sense, a Christian sense, an Islamic sense, or in an atheistic sense because evolutionary science is neutral on the question of whether God exists or not.

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I’m sure don’t need to nit pick capitalization. Though I agree with the sentiment.

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It is not a nit pick. Most people capital their God and don’t capitalize other people god(s). Most people capitalize their holy book - Bible and don’t capitalize other people’s holy books. I don’t want to give George the opportunity to call capitalized Evolution the God guided kind and the lower case evolution as the atheist kind.

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@Patrick

Isnt that your car alarm i hear outside?..

@gbrooks9 he has a point. He is trying to explain science neutrally. Push back I him when he is atheist ornery, not when he is serving the common good like this.

Okay, glad that George gets the neutrality of evolutionary science. Now both the Christian and the atheist can claim the benefits to our lives that comes from the knowledge gained in the study of evolutionary science. Btw - I hope everyone has gotten their flu shot. Last years flu killed 80,000 in the US and more than 900,000 people were hospitalized with the flu (including me). This year’s flu shot will be marginally effective so the only way to protect yourself and loved ones is for everyone to get a flu shot.

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@swamidass

Patrick’s rules of semantics do not reflect the nuances required for this site. Im “communicating”… he is obfuscating.

You say that i am pushing back? 1) I thought i just had good hearing. And
2) he almost always pushes first.

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Going to post on this soon! @evograd has a phenominal blog post on this.

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Either Bechly didn’t read the article, or he’s deliberately mispresenting the authors. The former seems unlikely given that he quotes the paper and refers to their results.

Bechly dedicates a whole section to the subject of “Incomplete Homework”, wherein he accuses the authors and other scientists of “not doing their homework” when it comes to the presence of cholesterol in non-animal species:

Paula Welander, a microbiologist at Stanford University, who was not involved in the study, said in an interview that “The study is based on the assumption that only animals create cholesterols, which … is fair with the current data but has the potential to change as we learn more about the many forms of life on Earth” (Wei-Haas 2018). Well, apparently the scientists did not really do their homework, because we already positively know that this fundamental assumption is simply incorrect…

He goes on to list several examples of cholesterols found in protists, fungi, choanoflagellates, etc. Did the authors actually overlook this? No.

Bechly cited 5 papers: Gonçalves Boëchat (2005), Kodner et al. (2008), Bühring et al. (2009), Weete et al. (2010), and Behrman & Gopalan (2005).

In their paper, Bobrovskiy et al. cited 2 of those papers (Kodner et al. 2008 and Weete et al. 2010), and 3 others: Najle et al. (2016), Gold et al. (2016), and Grabenstatter et al. (2013). All on the subject of non-animal cholesterols. It’s simply dishonest for Bechly to say the authors “didn’t do their homework” when they clearly cited and discussed these papers.

The relevant passage from the original paper:

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.

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.

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