Talk:Last universal common ancestor

Recent Reseach 2021

This could be of interest:

https://www.inverse.com/science/hydrogen-powered-life?utm_source=pocket-newtab-global-en-GB (How did life arise? New study offers fundamental evidence for a disputed theory)

points to:

https://www.frontiersin.org/articles/10.3389/fmicb.2021.793664/full#B62 (Energy at Origins: Favorable Thermodynamics of Biosynthetic Reactions in the Last Universal Common Ancestor (LUCA))

79.74.128.144 (talk) 01:21, 26 December 2021 (UTC)

It shows that basic components can arise spontaneously; what it doesn't show is how those components can be combined, which does require an input of energy. That leads to all the questions about how you manage with or without an ATPase, a major reason why the energy available via the "free" pH gradient in a hydrothermal vent is of interest. Any alternative habitat scenario must of course answer the same question. Chiswick Chap (talk) 08:06, 11 October 2022 (UTC)

removing 2016 weiss et al study

i removed the 2016 weiss et al study from the lead. it does not belong there, it's a preliminary study at best and a more recent study suggested that > 80% of the genes it identified in LUCA were false positives of its methodology. see: "A New Analysis of Archaea–Bacteria Domain Separation: Variable Phylogenetic Distance and the Tempo of Early Evolution" Haddarr (talk) 05:24, 26 December 2021 (UTC)

Weiss et al is certainly a seminal paper in the field. The paper you mention is discussed and cited in the article. Chiswick Chap (talk) 08:08, 11 October 2022 (UTC)

Citations in the lead

There are 25 citations currently in the lead, and 23 of them (!) are not used anywhere in the article body. This runs contrary to the "no new materials in the lead", as the lead is meant purely as a summary of the rest of the article. If those 25 sources are important, they should be in the body, either as well (if the lead text is debated) or removed from the lead altogether. Currently, it's just a mess. Chiswick Chap (talk) 13:27, 9 May 2022 (UTC)

Well since that clearly needs fixing, I've created a new 'Age' section and moved the materials out there, but for some 'Historical' stuff which has gone to that section. Chiswick Chap (talk)

Was this an individual organism? Or a population?

I have to say I'm slightly confused by the opening sentence, as to what this LUCA thing actually is. An individual, or a group of individuals? It's described as a "population" but then other parts of the article imply it was just a single bacterium or similar.  — Amakuru (talk) 22:52, 8 September 2023 (UTC)

It's spoken of in both ways. There was certainly a population of similar cells. However all living things come by definition from just one of these. Chiswick Chap (talk) 12:12, 9 September 2023 (UTC)

The Question from @Amakuru is concerning the “confusion”, I mentioned in my update from 20 September 2023. For example numerous authors use the term LUCA while it should be UCA. Maya Kandler (talk) 12:22, 23 September 2023 (UTC)

As you say, that has already been addressed; if more is really needed, then feel free to add and cite it (in the article body, not the lead, see below). But since this article is called "LUCA", and since as you rightly say many authors use the term, it is a "term of use" and we as an encyclopedia can properly have an article on it. It is fine to mention that "UCA" is an alternative, but it is not our job to say that a term in wide usage is "wrong", whatever that would mean. The other point is that we can't start talking about "UCA" in the lead: the lead is only a summary of the rest of the article, so there must be a discussion in the article body, presumably discussing the subtleties of UCA vs LUCA in terms everyone can understand, for the lead to summarize. Chiswick Chap (talk) 12:37, 23 September 2023 (UTC)

File: Phylogenetic_tree_of_life_1990_LUCA.svg - Please correct

This scheme is based on the cited original publication (Woese, Kandler, Wheelis 1990, Fig. 1, page 4578), called a “universal phylogenetic tree in rooted form, showing the three domains”. The term LUCA (last universal common ancestor) is not used. The author of the file mentioned above should explain, that he has added the term LUCA.

In addition, Woese et al. proposed the new taxon Eucarya for the third domain (instead of the former terms Eubacteria, Archaebacteria, Eukaryota). Please kindly use the designation of the original. Maya Kandler (talk) 12:29, 23 September 2023 (UTC)

I'm not at all sure what we should do here, as heading the LUCA article with a 1990 tree with obsolete nomenclature and without the label "LUCA" feels like a leap backwards in time, and it would certainly confuse readers. We may do better to drop the Woese et al. connection for the image caption and simply show the consensus arrangement of the domains, a far simpler diagram. Let's try that. Chiswick Chap (talk) 12:44, 23 September 2023 (UTC)

Eukarya is not obsolete, it is the current name for the domain.

Eukaryote(s) refers to the member(s) of this domain.

See Wikipedia-Article Domain, Textbook Brock or e.g. https://www.biologyonline.com/dictionary/eukarya ; https://www.biologyonline.com/dictionary/eukaryote

Current Textbook-Definitions of LUCA refer to the three domains, so it is important, to start the article with Woese et al. and add “LUCA” in the original scheme as you did (I just asked you to explain, that you added LUCA). So everyone can see the point/node of diversification.

The original scheme illustrates the diversity of organisms much better, than your new simpler scheme. Maya Kandler (talk) 14:05, 23 September 2023 (UTC)

It is "Eucarya" that I indicated was obsolete. I've tweaked the diagram for you and indicated that Woese et al did the tree but not the LUCA label. Chiswick Chap (talk) 14:33, 23 September 2023 (UTC)

Thank you! Maya Kandler (talk) 08:11, 24 September 2023 (UTC)