Talk:Eukaryogenesis

PNAS paper by Margulis et al is mainstream science

An editor has seen fit to try to remove a brief mention of a research article in PNAS in 2006, asserting it's "fringe". However, PNAS is a (highly) respected mainstream journal with a robust scientific peer-review process. Now it may well be that the paper's proposal is incorrect: science goes like that. The appropriate response for mainstream science mistakes, if such it be, is not editorial censorship ("we know best"), but the addition of later sources that question or refute the proposal made. Since "once notable, always notable" is a correct Wiki-slogan, we do not go about deleting relevant accounts of an idea's history; instead, we update them from the latest sources. Chiswick Chap (talk) 10:29, 25 June 2026 (UTC)

There are several issues with this point of view.

1)The hypothesis posited in that paper never met academic consensus. This is well known by molecular biologists (incidentally, I a former mol biologist). See this obituary of Margulis on Science: "She championed the idea that eukaryotes gained their flagella (which differ from the prokaryotic flagella) by the acquisition of a motile bacterium, a spirochete, a view that has few subscribers today."; the obituary on PNAS itself "Throughout her life, Lynn maintained as well that the flagellum, the whip-like structure responsible for locomotion in many eukaryotic cells, also originated as a symbiotic bacterium, but this theory has never garnered strong support from other biologists"; this historical analysis paper on Margulis' ideas (accessible via Wikipedia Library) states multiple times that the hypothesis was never accepted; also this other obituary clarifies that " While the termite gut microbial community presented many intriguing questions regarding the relationship between the myriad of spirochetes in the gut and the symbiotic flagellates, no molecular or biochemical data were ever developed to support the idea that these motility symbionts evolved into cell organelles."

2)PNAS was actually infamous, in the past, for publishing extremly sketchy papers via the "contributed submission" route, where NAS members or people endorsed by NAS members could basically skip peer review (they picked up their own reviewers and submitted themselves the reviews alongside the paper). The system has been basically abolished in the last years, but the 2007 source in the article has been, unsurprisingly, gone through this route (see the note "Contributed by Lynn Margulis" right above the abstract). In general, "contributed" PNAS papers, especially older than 10-15 years, should never be considered WP:RS unless other academic sources consistently support them as reliable.

3)Notability has zero to do with this issue. If one were to write an article on Margulis' hypothesis on the role of spirochete in eukaryogenesis, that would be entirely correct to point that a discarded or fringe hypothesis could be notable (and it is). Here however, unless we want to present a paragraph on past hypotheses on eukaryogenesis (which could be a good idea,incidentally), we have to deal with WP:UNDUE and WP:FRINGE: that is, not giving undue weight to fringe hypotheses and, most importantly, presenting them as if they were not fringe. Therefore, we definitely do delete outdated or fringe research when it is out of context, while of course we present it in sections or articles that give it the correct context. Whatever is the place for Margulis' spirochete hypothesis in this article, it is not in a section where it is presented as scientifically accurate information. cyclopia^speak! 10:51, 25 June 2026 (UTC)

This is just anecdotal, but I have been in conversations with several evolutionary biologists that knew Lynn Margulis in person and they mostly agree that several of her hypotheses that later would be crowned as achievements were not (or were rarely) researched, and many, like the flagella and her phylogenetic framework from her published books, were extrapolations that barely reflected actual research. But she was a great spokesperson. I understand that the popularity she gathered due to her publications and general charisma warrants a place in this article, but like Cyclopia says, we should be careful in assigning her proposals as "mainstream science". — Snoteleks (talk) 11:18, 25 June 2026 (UTC)

Margulis had an amazing intuition and the stubborness to put it forward, but then, as it happens to many brilliant scientists, she became enamored with her own theories and did not accept to let them go even when evidence was overwhelmingly against. The endosymbiotic hypothesis for the flagellum etc. was a very good and intriguing hypothesis; too bad data never supported it. cyclopia^speak! 11:22, 25 June 2026 (UTC)

Yes. Then we need to find some words that express caution about her proposals, noting that her core suggestion that symbiogenesis occurred is accepted as correct. This article isn't really the place for that as the symbiogenesis section is just a summary. Chiswick Chap (talk) 11:25, 25 June 2026 (UTC)

That symbiogenesis occurred is obviously well established, but that paper and that proposal should not be cited there. If anything, it belongs to a section on historical views on eukaryogenesis. cyclopia^speak! 12:17, 25 June 2026 (UTC)

Yes. The "main" link here needs to be accompanied by a short "summary style" paragraph representing the Symbiogenesis article's contents, which might resemble that article's lead section. It would be far better

1) to update that article, complete with an account of Margulis's errantry and reliable refutations of it, and with "new" papers like the one you added today,

2) to update that article's lead section to summarize its "main points", and

3) to update the very brief summary here from the above (in that order). This article probably isn't the place for the new paper, either. Chiswick Chap (talk) 12:24, 25 June 2026 (UTC)

Sorry, I replied below but before seeing your comment. The symbiogenesis article briefly cites the flagella/spirochete issue, but indeed it's not well sourced. I'm not sure of what you mean by the "main link", summarizing main points there etc. cyclopia^speak! 12:33, 25 June 2026 (UTC)

The short paragraph-length section here in Eukaryogenesis#Symbiogenesis is a summary with "main" link of the Symbiogenesis article; additions should go *over there* per the 1-2-3 procedure just outlined. Chiswick Chap (talk) 12:51, 25 June 2026 (UTC)

Makes perfect sense, thanks. cyclopia^speak! 14:50, 25 June 2026 (UTC)

For now, I've put the hypothesis in a footnote, along with the abovementioned papers that describe its scientific status. If we manage to make an historical section, then it can go back to main text there. cyclopia^speak! 12:30, 25 June 2026 (UTC)

GA review

This review is transcluded from Talk:Eukaryogenesis/GA1. The edit link for this section can be used to add comments to the review.

Nominator: Chiswick Chap (talk · contribs) 10:26, 23 September 2026 (UTC)

Reviewer: Snoteleks (talk · contribs) 22:14, 23 September 2026 (UTC)

Hello Chiswick Chap, I am so glad this article has caught your attention and efforts! As a person somewhat knowledgeable on the subject (I even met Moisès before seeing him present the 2026 paper), I'm happy to review it. Comments coming soon... — Snoteleks (talk) 22:14, 23 September 2026 (UTC)

Many thanks. I look forward to working on this with you and will value your input. Chiswick Chap (talk) 07:40, 24 September 2026 (UTC)

Preliminary checks

• Copyright violations: Earwig's Copyvio Detector shows none
• Spot check:

[5] - good

[15] - good

[30] - good

Criteria

• Well-written Good but see comments below
• Well-referenced
• Good coverage
• Neutral
• Stable
• Illustrated

Round 1 comments

Lead

• I suggest extending it a bit more to reflect the current content. The lead as it is right now is disproportionately focused on the LECA aspect as opposed to the actual genesis.

Context

• This is where I think the page falls short the most. The section has great potential as both the starting point/justification for the whole article and the bridge with the following sections, however as it is right now there is little connection between sections. The first paragraph Life arose on Earth [...] is a good introduction to ground the readers in the context of early life and the fact that eukaryotes somehow arose from it, leading to the life they are familiar with. I strongly suggest continuing it with two additional paragraphs or sentences:

1. A brief statement pointing out that we just don't know what happened between the bacteria/archaea split (or FECA) and LECA. We know eukaryotes have certain defining characteristics, mentioned in the first paragraph, so they must have appeared somewhere inbetween, but there is a considerable "gap" of information (fossils, etc.). This is also echoed by the first image.
2. Then a statement that ties this up, essentially saying "hence why eukaryogenesis is explored first through reconstructing the characteristics of LECA, based on the eukaryotes that exist today, and through [protein analysis, cell reconstructions, etc.] reconstructing the possible processes that led to those characteristics from prokaryotes." That way the reader can better understand the strong emphasis on LECA in the rest of the article, it will not feel as out of place.

• I took the liberty to substitute eukaryotes with prokaryotes and do other minor grammar cleanups
• The first paragraph could also be improved, as statements like rapidly-dividing are not reflective of the true biological divide. I suggest rewording the remaining sentences of the paragraph, perhaps as something like: "LUCA gave rise to two domains of life, the bacteria and the archaea, collectively known as prokaryotes. From among these comparatively small and simple organisms arose the eukaryotes, distinguished by the cell nucleus and a higher degree of cellular complexity, with the cytoskeleton, endomembrane system, and mitochondria. The eukaryotes form the third domain of life and include all complex cells and most types of multicellular organisms, such as the animals, plants, and fungi."

Symbiogenesis

• The first sentence needs to be more explicitly related back to eukaryogenesis, something like "According to the theory [...] by Lynn Margulis, the eukaryotic cell originated from an archaeal cell that gained a bacterial cell as a component (or symbiont).
• I think it would also be fitting to include some final meta-statement like "this remains the leading theory to explain the origin of eukaryotic traits, but the specifics involved in this process continue to be debated". It is a good segway into the 'Scenarios' section.
• Very nice image!

Last eukaryotic common ancestor

• Considering the improvements suggested above I find it more fitting to place this section directly below the 'Context' section, before the 'Symbiogenesis' section. My reasoning is that readers could follow this flow: 'Context' (eukaryogenesis means tracing back from LECA) → 'Last eukaryotic common ancestor' (explanation of what basic traits are expected to have been in LECA) → 'Symbiogenesis' (the basic theory of how life acquired these traits) → 'Scenarios' (specifications on the details of said theory, how it actually could have taken place) → 'Diversification: crown eukaryotes' (extra info on the aftermath and root of eukaryotes).
• This section should be limited to traits that LECA had, not the order in which it got them. The 2022 hypothesis by Bremer et al. in the paragraph starting with It had been proposed [...] represents one of the alternative scenarios and is better suited in that section instead.
• Referencing the 'compartments' mentioned in the 2nd paragraph with some examples would be nice (I assume Golgi apparatus, endoplasmic reticulum and nuclear envelope?)
• If you are in the mood, the LECA reconstruction image from doi:10.1371/journal.pbio.3002917 {{doi}}: unflagged free DOI (link) is licensed as CC BY 4.0
• Begin the 'Genetic mechanisms' subsection with "In eukaryotes, as opposed to prokaryotes, the mechanisms for transcribing..." or similar, instead of an "Its"

Scenarios

• This is out of scope for a GAN review but: for the last two paragraphs on the competing sequences, while I understand committing to a handful of papers, it would probably be better to draw a large picture of all the hypotheses. I know a good review here doi:10.1016/j.cub.2023.07.048 (see Box 1). The first paragraph is a good intro.
• I would love to see the 'Associations of microbes' subsection expanded to include other associations, not just theorized in the 2026 paper but earlier (maybe even the spirochaetes mentioned in the footnote?). It is a long-established thought that there were more than two prokaryotes involved in the process (as pointed out in the review I linked).

Diversification: crown eukaryotes

• Looking good! I think brevity here is the way to go.

External links

• Is there a way this external link to a news article could be replaced with a citation for the 'Eukaryotic sex' subsection instead?

In conclusion, the article could use some tinkering due to its massive scope and due to how it also serves as the article for LECA, but is nonetheless on an easy path towards GA status. I am waiting until the comments above are addressed — Snoteleks (talk) 23:42, 24 September 2026 (UTC)