Prokaryotes, Eukaryotes, and their cousins

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This interesting topic popped up in another conversation, where somebody suggested reading the available literature on this subject.
That seems like a valid and very appreciated suggestion.
We want to learn more.
Can we share references to papers on this interesting topic?

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Here’s a paper on this topic:

Relative timing of mitochondrial endosymbiosis and the “pre‐mitochondrial symbioses” hypothesis

Toni GabaldĂłn

IUBMB Life. 2018 Dec; 70(12): 1188–1196.
Published online 2018 Oct 25. doi: 10.1002/iub.1950
PMCID: PMC6282991
PMID: 30358047

The origin of eukaryotes stands as a major open question in biology. Central to this question is the nature and timing of the origin of the mitochondrion, an ubiquitous eukaryotic organelle originated by the endosymbiosis of an alphaproteobacterial ancestor. Different hypotheses disagree, among other aspects, on whether mitochondria were acquired early or late during eukaryogenesis. Similarly, the nature and complexity of the receiving host is debated, with models ranging from a simple prokaryotic host to an already complex proto‐eukaryote.

simple eukaryogenesis models that assume a binary symbiosis between an archaeon host and an alpha‐proteobacterial proto‐mitochondrion cannot explain the complex chimeric nature that is inferred for the eukaryotic ancestor.

The origin of eukaryotes remains one of the most difficult questions in evolutionary biology. Given the scarcity of data, most proposed scenarios for the origin of eukaryotes are necessarily highly speculative.

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I’m looking at this paper, though it’s very difficult for a non-biologist like me.

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What questions do you have?

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@pawas, take a look a this example of evolving endosymbiosis in the laboratory:

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This can’t be right. Is the author a Creationist?

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If you look, it’s a question about the details. Whatever the solution, it still involves endosymbiosis to account for mitochondria and the eubacterial portion of the nuclear genome, and it still involves an archaeal host.

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Yes, details are important.

Is it only the other details that are “highly speculative”?

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I grow wearing of passive-aggressive sniping. Do you have any sincere questions?

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Sure. Can you admit that we just don’t know and probably never will know is an appropriate answer? Further, once you admit that, can you also admit that you are just choosing to believe what you want to believe?

Science has little to nothing to do with any of it for either side. Perhaps once we acknowledge that we might begin to have productive conversations.

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That sounds suspiciously like the claim that you have to know all the details of how the eukaryotes evolved before you can claim that they did.

Science and in fact life in general manages to proceed just fine without us knowing all the possibilities (or all the details) before making a judgment or inference. What you are doing is engaging in special pleading. A fallacy.

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Will we ever know the exact placement of every footstep that Napoleon took as he moved into Russia? Nope. Are we still confident that Napoleon invaded Russia? Yep.

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I find it hard to believe those were sincere questions. And I find your pose as impartial referee ludicrous. So, sorry, no substantive response is possible.

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Very interesting indeed. Thanks

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I don’t know.

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Yet another bad analogy.

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What’s wrong with Mung’s questions?
What is insincere about them?

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They don’t like the answers.

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Takes too long to explain. Prior experience with Mung would help.

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Yet another bare assertion.