Buggs: TSS and the Flagellum

Referring to the injectisome as the type three secretory system (TTSS), Dawkins wrote (p. 132):

The protein molecules that form the structure of the TTSS are very similar to components of the flagellar motor. To the evolutionist it is clear that TTSS components were commandeered for a new, but not wholly unrelated, function when the flagellar motor evolved…Evidently, crucial components of the flagellar motor were already in place and working before the flagellar motor evolved.

Thus, Dawkins viewed the injectisome as an evolutionary precursor for the flagellar motor.

Although the flagellum has been proposed to be the evolutionary ancestor of T3SSs, the structure of the flagellar motor is significantly different from that of the T3SS basal body. The rod in the basal body of the Salmonella T3SS consists of two proteins, PrgJ and PrgI, and adopts a relatively simple helical structure. In contrast to the tight contacts of the T3SS rod with the secretin channel and the inner membrane ring, the flagellar rod has few contacts with the LP ring to facilitate its high-speed rotation and torque transmission. In addition, unlike the C24-symmetric inner membrane ring assembled by PrgH and PrgK in the Salmonella T3SS, the MS ring of the flagellar motor is composed of 34 FliF subunits with mixed internal symmetries. Therefore, the flagellar motor has evolved special structural elements for bacterial motility.


It seems to me that the quoted bit doesn’t address the main question, which is one of homology, and is not relevant to whether TS33 evolved from a flagellum base or whether the flagellum base evolved from TS33. Bugg cites other evidence that’s relevant, though.


I need some clarity here. Is Richard Buggs an ID proponent, because I see no sense in picking on Dawkins for a hypothesis that clearly didn’t originate from him and which seems to be receiving little support from available data?

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There seem to be at least two major problems with Buggs article.

One is that Buggs article mainly consists of bare assertions none of which actually follow from the the putative factoids he attempts to derive them from.

Take this example:

In other words, even parts of the two structures that seem to correspond to each other are very different. Thus, parts of the injectisome could not simply be “commandeered” for the flagellar motor.

But that just doesn’t follow. Buggs simply has no idea whether any part of the T3SS could function as part of a pre-flagellar system. It is noteworthy that the part of the flagellum that corresponds to the T3SS really can function as a protein secretion system. That is one part of their function in the flagellum: to export the protein components that make up the parts of the flagellum that extend through and to the outside the outer membrane. The flagellum’s assembly is only possible through the retainment of this capacity of the flagellar T3SS to translocate proteins across the cell membrane.

More importantly is that the proposal is not that the extant flagellum derived from the extant T3SS, but that an ancestral state in the evolution of the flagellum was similar to and had a function similar to the T3SS. It is to be expected that both the flagellum and the injectisome have further specialized and diverged from their common ancestral systems.

Buggs is making a “you can’t turn pigs into squids”-argument against evolution. But neither organism evolved from each other, they derive from a common ancestor.


Oh and, of all people arguing for flagellum evolution, why focus on Dawkins and, of all things, his book that isn’t even specifically about evolution or biology, but merely contains a rebuttal to a pro-ID argument? These ID people are OBSESSED with Richard Dawkins. Dawkins is actually just paraphrazing Kenneth Miller on flagellum evolution (and it’s on page 158, not 132).


He certainly sounds like one:

I do note, however, that he is no longer listed as a member of the scientific panel of “Truth in Science”:


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Yes, he was part of a(n apparently moribund) DI UK offshoot Truth in Science.

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All of that seems to be true, but he also is tenured scientist in the UK has done a good amount of solid, legitimate, and uncontroversial work. That doesn’t give him a pass on anything in this article per se, but I do believe this is also important to note alongside the criticism.


Yes, he has also published in the actual journal Nature, and not just its offshoot blogs:


Of course, he then went and gave this article a creationist spin on the offshoot blog:


I see. It seems like this “Truth in Science” group hasn’t had much success in the UK, any reasons why?

Absolutely. We must not fail to give due credit for worthy accomplishments.

I got to know him from his exchange with Dennis Venema, but he seemed like an “evolutionist” to me at the time who was just challenging Dennis on some of his arguments. He has been mentioned on PS a couple of times, but I began to suspect he was ID when Prof. Swamidass shared a post composed by him on the inability of evolutionary biologists to explain the origin and evolution of flowering plants.

IMO he is abusing the Nature platform to post embarrassing pablum that belongs on a personal blog site. The article is a joke, but even more problematic is the hijacking of the credibility of the Nature platform/brand to post religiously-motivated blather focused on one particular strawperson. I think Nature should be looking hard at his use of their blog site.


Nothing like a good fight to draw web traffic though. :man_shrugging:


Nothing you’ve said is in conflict with what said I :slight_smile: .

I can think of two potential reasons why:

  1. Many of the DI’s offshoots tend to be fairly hit-or-miss in terms of success. Few (if any) tend to survive more than a few years.

  2. The level of support for ID in the UK is likely to be lower than in the US, making it more difficult for an ID organisation to sustain itself in the longer term.

This actually seems to be somewhat of a pattern with ID in the UK (in contrast to its American efforts). Many (most?) of the prominent spokesmen of Truth in Science and the Centre for Intelligent Design have positions within mainstream academia. This may be a result of a lack of an alternative conservative Christian academic ecosystem in the UK.

I will leave it to the scientists on this forum to decide if that improves the quality of the UK ID efforts over those of its American colleagues.

To be clear, Buggs is not really publicly declared as ID. It isn’t clear what his personal views are on a range of relevant questions. He is connected to people in the ID movement, but he also has some distance, a bit like James Tour.

To be clear, Buggs has been a prominent member of a group, Truth in Science, whose purpose is promotion of ID, and published this defense of ID.

So yes Joshua, by any reasonable standard, Buggs is really “publicly declared as ID.”

This is true of many ID advocates. It is a ‘big tent’ movement after all.


That’s helpful. I had not seen that article before. Makes it a lot easier to address his position going forward for me.

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Interesting. The clear implication would be that Buggs uses ID approaches in his published science, since it’s apparently so fruitful. And yet somehow I’m dubious that that is the case, and I also suspect that his co-authors would be unaware of such a contribution.

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Going through that article, I couldn’t help but notice the typical ID fixation on darwinism as if it were still the dominant paradigm in evolutionary biology. In the end, he made no convincing case for ID as a science.

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