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I don't have access to the cited Science News article, but numbers as large as 10^2860 are ridiculous. This must be a typo. Mphelbert ( talk) 18:27, 24 July 2010 (UTC)
{{
cite journal}}
: CS1 maint: date and year (
link){{
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: CS1 maint: date and year (
link)Concerning this abstract/paper by Douglas L. Theobald (Theobald DL on his paper) which is cited in the Wikipedia article at http://en.wikipedia.org/wiki/Universal_ancestor
> "Nature. 2010 May 13; 465(7295):219-22. > A formal test of the theory of universal common ancestry. > Theobald DL. > Department of Biochemistry, Brandeis University, Waltham, > Massachusetts 01778, USA. dtheob...@brandeis.edu > Comment in: > * Nature. 2010 May 13;465(7295):168-9. > Abstract > Universal common ancestry (UCA) is a central pillar of modern > evolutionary theory. As first suggested by Darwin, the theory of UCA > posits that all extant terrestrial organisms share a common genetic > heritage, each being the genealogical descendant of a single species > from the distant past. ***The classic evidence for UCA, although > massive, is largely restricted to 'local' common ancestry-for example, > of specific phyla rather than the entirety of life-and has yet to > fully integrate the recent advances from modern phylogenetics and > probability theory. Although UCA is widely assumed, it has rarely been > subjected to formal quantitative testing,*** and this has led to > critical commentary emphasizing the intrinsic technical difficulties > in empirically evaluating a theory of such broad scope. Furthermore, > several researchers have proposed that early life was characterized by > rampant horizontal gene transfer, ****leading some to question the > monophyly of life.**** Here I provide the FIRST, to my knowledge, > formal, fundamental test of UCA, without assuming that sequence > similarity implies genetic kinship. I test UCA by applying model > selection theory to molecular phylogenies, focusing on a set of > ubiquitously conserved proteins that are proposed to be orthologous. > Among a wide range of biological models involving the independent > ancestry of major taxonomic groups, the model selection tests are > found to overwhelmingly support UCA irrespective of the presence of > horizontal gene transfer and symbiotic fusion events. These results > provide powerful statistical evidence corroborating the monophyly of > all known life. > PMID: 20463738 [PubMed - indexed for MEDLINE]" > From - http://www.ncbi.nlm.nih.gov/pubmed/20463738 (fromhttp://en.wikipedia.org/wiki/Evolution)
Look how in the following that two Wikipedia contributors (Mike Steel and David Penny) have falsified data from the SAME paper/abstract (abstract by Theobald, DL, also known as Douglas L. Theobald) that I cited above, crediting *themselves* with writing a book or something or other (likely a letter to the magazine that printed Theobald's paper) on the subject of the article/paper on the SAME DATE as the article/paper and linking to Theobald's paper.
From Wikipedia's article Last Common Ancestor at - http://en.wikipedia.org/wiki/Universal_ancestor - last updated 17 Sept. 2010
David Penny and Mike Steel write (notice the quoted material is a partial sentence only and IS NOT CONTAINED in the abstract/paper by Theobald, which is at the top of this post):
"There is strong quantitative support, by a formal test"[1] for the theory that all living organisms on Earth are descended from a common ancestor.[4]"
Note who their sources for this statement are: themselves (#4), and the paper/abstract I cited above (#1). And the PMID numbers in both #1 and #4 are links which lead to the same abstract/paper by Theobald.
Linda 444 ( talk) 19:07, 27 September 2010 (UTC)
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This needs to be updated with respect to some of the evidence points given in the "Evidence of universal common descent". There are elements of this that, while evidentiary, is not true of all current life on earth.
Examples include:
There is plenty of evidence still, of the last universal ancestor; this is just a matter of correcting the article qualifications to be more accurate in view of later discoveries.
This article states that there was an arbitrary choice of codon patterning. I am not an expert, but last I checked, there was evidence that each codon tends to be more attracted to its amino acid in solution than to any other. Also, to describe the universal ancestor as already having 3-base codons etc should be cited in my opinion. Any such organism must have evolved from something simpler, or been put there by an intelligent designer. - Richard Cavell ( talk) 12:11, 19 March 2011 (UTC)
I am baffled by the appearance of a phylogenitic tree based on cavalier-smith papers being presented as the accepted view of the tree of life. It is all but the accepted view. I find the Cavalier-smith papers very interesting and bold, but they must be read in context (the reviewers' comments on his biology direct paper spell it out). Molecular phylogeny may be wrong, but until the consensus is against it, it should be the main view presented. Putting together a cladogram requires a lot of effort and I do not want to summarily delete it, but in most scientific litterature LUCA is not a bacterium, but a bacterium/neomuran ancestor. Most papers that do claim it to be a bacterium place it in the Firmicutes and not with a basal phylum "Chloroflexi" (the phylum does not have a proper name and Cavalier-Smith coined the term Chlorobacteria, but that is not how the system works another example why the papers require a pinch of salt). Therefore should this large tree be transfered elsewhere? -- Squidonius ( talk) 03:49, 1 August 2011 (UTC) Moved here for now: Phylogeny [1] [2]
References
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link)
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LUCA |
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Notes:
1 Eobacteria
2 Glidobacteria
3 Negibacteria
4 Frankiineae
5 Streptomycetes
6 Arthrobacteria
7 Arabobacteria (Neomura stem from within Arabobacteria)
8 Archaeobacteria
Eurybacteria = Selenobacteriales, Heliobacteriaceae, Fusobacteriales & Thermotogales
Aphragmabacteria = Mollicutes & Erysilothrichia
Terrabacteria: Chlorobacteri, Deinococci, Cyanobacteria, Endobacteria, Actinobacteria & ?Fusobacteria
Selabacteria: Terrabacteria & Hydrobacteria
♠ Strain found at the
National Center for Biotechnology Information (NCBI) but has no standing with the
Bacteriological Code (1990 and subsequent Revision) as detailed by
List of Prokaryotic names with Standing in Nomenclature (LPSN) as a result of the following reasons:
• No pure culture isolated or available for Prokayotes.
• Not validly published because the effective publication only documents deposit of the type strain in a single recognized culture collection.
• Not approved and published by the
International Journal of Systematic Biology or the
International Journal of Systematic and Evolutionary Microbiology (IJSB/IJSEM).
Let's start Auto-Archiving this Talk Page. The Mysterious El Willstro ( talk) 01:45, 30 April 2012 (UTC)
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I removed two points from the features section. If people have objections to this, let's discuss it here :)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
The information in the "Criticism" section can be broadly defined as "Creation Science." These are arguments commonly used to support the pre-conceived conclusion that humans evolved independently of all other organisms on earth. Basically, the author's position is that instead of there being ONE family tree for all life on earth, there are a bunch of different trees and that in some cases(particularly that of humans) the tree is simply linear. While the article should probably contain some general comment to the effect that there are some other non-trivial hypotheses about the exact path to our current biodiversity, it is NOT acceptable for non-NPOV theories outside sphere of accepted science to comrprise 60+% of the article. —The preceding unsigned comment was added by 167.83.10.20 ( talk) 20:15, 11 April 2007 (UTC).
Let us PLEASE not get religious "criticisms" into this article. That should belong in Conservapedia. Let's keep it proper science on this page. — Preceding unsigned comment added by 149.172.153.15 ( talk) 10:29, 22 November 2012 (UTC)
I am removing the "LUCA is refuted" paragraph, it's thinly disguised creationism. The somewhat relevant parts of it, about problems rooting the tree of life, are already addressed in the article via the section on gene transfer.
- Blueshifter 15:26, 29 April 2007 (UTC)
The criticism section smacks of creationist nonsense right from the first sentance. —Preceding unsigned comment added by 12.33.211.29 ( talk • contribs) 09:56, 20 June 2007
It shouldn't automatically be dismissed as 'nonsense'. People need to be open to other viewpoints and interpretations of the scientific evidence. I do understand the rules of needing reliable/verified material for the wiki, though. But people still need to have more respect for other viewpoints. — Preceding unsigned comment added by 98.213.92.109 ( talk • contribs) 05:06, 9 January 2012
Removed unsourced, weasely criticism section. There is no doubt some published scientific criticism - so find and cite it if the section is to be re-written. Vsmith 11:28, 20 June 2007 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I created a paragraph that attempts to list all the properties shared by all independently living organisms (not viruses), based on the assumption that the LUA must also have had these properties. I had lots of fun doing this. It is clearly incomplete; be bold, improve it. Emmanuelm ( talk) 16:15, 11 January 2008 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I added this paragraph. A bit weak, but I think it is interesting. If you delete it, I will not revert. Emmanuelm ( talk) 17:08, 11 January 2008 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
According to the definition of Ur-organism found in its article, there seems to be no need for both articles on "ur-organism" and " LUCA". I am not familiar with the ur-organism concept, but it also seems possible to me that it actually refers to the first instance of life or even the First Common Ancestor (as discussed above), and that the definition listed at Ur-organism is incorrect. Does anyone know anything more about this? Should the two be merged and disambiguation be set up or should the definition of ur-organism simply be rewritten accurately? - Thibbs ( talk) 21:58, 3 May 2008 (UTC)
Later in the chapter he refers to the ur-organism as "a protobiotic form." This source, then, clearly supports the idea that "ur-organism" is a term for the First Universal Ancestor (not to be confused with the First Living Organism) rather than the Last Universal Ancestor. There are a few corroboratory sources from the social sciences or religious scholarship which I would hesitate to rely upon (eg. Rist's paper and Unger's article which was referenced in Google Scholar...). There are also an irritating number of folks online who employ the term "ur organism" to mean "your organism" as in "u take ur organism and put it undr teh microscope." The wiki article, Ur-organism, references Darwin as the originator of the term and I have run text searches on online versions of Origin of Species to no avail. I have not yet run tests on Descent of Man or his other works. I notice that Oparin has also been referenced but I have not yet examined his use of the term (if indeed he has used it at all). Before doing difficult-to-reverse changes to wiki, though, it seems to me that we need more authority than the unreferenced definition found in the ur-organism article. If anyone can find any information on the use of this term it would be very helpful. - Thibbs ( talk) 00:37, 5 May 2008 (UTC)"We envision the Ur-cells as being very simple, whereas the universal ancestor must—by comparison to these—have been quite complex. Thus, the gap between the approach from above and the approach from below must be filled by an evolutionary path from the ur-organism to the universal ancestor. The problem is not simply the origin of life, it is the physical formation of the the Ur-organism and a subsequent evolutionary epoch giving rise to the universal ancestor."
This looks interesting. Info from this source might be good to extend the article with.
"Why Darwin was wrong about the tree of life". New Scientist (2692): 34–39. 21 January 2009.
-- InsufficientData ( talk) 21:47, 25 January 2009 (UTC)
The article at Organism contains material about the last universal ancestor that has been removed from this article, namely whether there is significant scientific debate about the existence of an LUA. See Organism#Was there a universal ancestor?. Should this article mention that there is a minority opinion held by the religiously motivated "intelligent design" advocates? -- Bejnar ( talk) 22:59, 11 December 2013 (UTC)
Are we talking about a species here, or about a single, individual cell? -- 77.7.152.59 ( talk) 02:03, 24 November 2010 (UTC)
References
There appear to be four possible names for this article, and it does not look as though the current one is the most usual. I did a google search (with "-Wikipedia") on the following terms (without the abbreviations), obtaining the following results:
Recent announcements in the media (such as the New York Times article cited in the item above) have all used "LUCA", which may not prove anything, but is suggestive. LUCA also reads as a clear descriptive term, which would be an advantage. Given LUCA's runaway top score, and for these other reasons, I propose that we rename the article, preserving redirects from the other three terms. Chiswick Chap ( talk) 18:07, 13 September 2016 (UTC)
2. Google Trends currently shows Last Universal Ancestor being used more in searches than Last Universal Common Ancestor: https://www.google.com/trends/explore?date=all&q=Last%20Universal%20Ancestor,Last%20Universal%20Common%20Ancestor,Cenancestor,Progenote
The 2 terms have traded places since 2004. I am not certain counting google searches is a scientific approach. I prefer Last Universal Common Ancestor as a more descriptive name. CuriousMind01 ( talk) 23:57, 13 September 2016 (UTC)
This does not indicate whether LUA may once have been a major term or not, but it is certainly far behind LUCA, and is apparently last behind Progenote and Cenancestor also. Chiswick Chap ( talk) 05:57, 14 September 2016 (UTC)
I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Last universal common ancestor's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.
Reference named "IND-20171002":
{{
cite web}}
: Unknown parameter |deadurl=
ignored (|url-status=
suggested) (
help)I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT ⚡ 14:38, 10 October 2018 (UTC)
I want to point out that the base of the tree has nothing to do with the origin of life. Any conclusion that comes from LUCA analysis can not directly touch the orgien of life. In the same way, I would take the results of Willian Martin's group very carefully, if you read the articles, the conclusions are not really well supported. Avazquez-salazar ( talk) 19:03, 24 October 2018 (UTC)
There are many inaccuracies with this article. For example, it says "Only 20 amino acids were used, only in L-isomers" -- but it's pretty well established that LUCA had selenoproteins. Much of the "Features" section lacks reliable sources (16-19 are all from more than a decade ago), and it would be reasonable to rewrite the paragraph (The genetic code was expressed into proteins ... chemical pathways) entirely. I also suggest combining Martin (2016)'s findings with the "Features" section. Allopathie ( talk) 02:53, 31 January 2019 (UTC)
Granted, the first sentence says that LUCA is sometimes called "progenote", but also says that it's a misnomer, so progenote is a different thing and should have its own article or redirect to somewhere else IMHO (perhaps Three-domain system or Darwinian_threshold#Before_the_Darwinian_Threshold). Apokrif ( talk) 16:25, 6 August 2019 (UTC)
In the Uni. of Bristol paper cited in the introduction, they themselves put a hard limit on the age of the LUCA at the date of the Moon's formation (in line with the giant impact hypothesis). It certainly defies credulity that cellular life could survive a collision between planets, given that the Earth's crust would likely liquify and the atmosphere would be briefly composed of gaseous rock.
Recent work on the age of the Moon constrains its formation between 4.40 and 4.45 Ga "A long-lived magma ocean on a young Moon". Science Advances.. This post-dates the 4,519–4,477 Ma range for the LUCA given in the bristol paper by 10's of millions of years at least. It appears that one of these papers (or the GIH) must therefore be incorrect.
Is it worth noting this in the article? As I think this casts significant doubt on the calibration used in the paper.
00A86B ( talk) 17:12, 18 August 2021 (UTC)
I'm not a scientist, just took interest to this subject.
This article describes LUCA as "population" of organisms. Shouldn't it be just an (one) organism? Especially as I saw another Wikipedia write-up alluding to an individual unicellular organism? Vusi Dlamini ( talk) 03:40, 20 September 2021 (UTC)
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)
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)
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)
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I don't have access to the cited Science News article, but numbers as large as 10^2860 are ridiculous. This must be a typo. Mphelbert ( talk) 18:27, 24 July 2010 (UTC)
{{
cite journal}}
: CS1 maint: date and year (
link){{
cite journal}}
: CS1 maint: date and year (
link)Concerning this abstract/paper by Douglas L. Theobald (Theobald DL on his paper) which is cited in the Wikipedia article at http://en.wikipedia.org/wiki/Universal_ancestor
> "Nature. 2010 May 13; 465(7295):219-22. > A formal test of the theory of universal common ancestry. > Theobald DL. > Department of Biochemistry, Brandeis University, Waltham, > Massachusetts 01778, USA. dtheob...@brandeis.edu > Comment in: > * Nature. 2010 May 13;465(7295):168-9. > Abstract > Universal common ancestry (UCA) is a central pillar of modern > evolutionary theory. As first suggested by Darwin, the theory of UCA > posits that all extant terrestrial organisms share a common genetic > heritage, each being the genealogical descendant of a single species > from the distant past. ***The classic evidence for UCA, although > massive, is largely restricted to 'local' common ancestry-for example, > of specific phyla rather than the entirety of life-and has yet to > fully integrate the recent advances from modern phylogenetics and > probability theory. Although UCA is widely assumed, it has rarely been > subjected to formal quantitative testing,*** and this has led to > critical commentary emphasizing the intrinsic technical difficulties > in empirically evaluating a theory of such broad scope. Furthermore, > several researchers have proposed that early life was characterized by > rampant horizontal gene transfer, ****leading some to question the > monophyly of life.**** Here I provide the FIRST, to my knowledge, > formal, fundamental test of UCA, without assuming that sequence > similarity implies genetic kinship. I test UCA by applying model > selection theory to molecular phylogenies, focusing on a set of > ubiquitously conserved proteins that are proposed to be orthologous. > Among a wide range of biological models involving the independent > ancestry of major taxonomic groups, the model selection tests are > found to overwhelmingly support UCA irrespective of the presence of > horizontal gene transfer and symbiotic fusion events. These results > provide powerful statistical evidence corroborating the monophyly of > all known life. > PMID: 20463738 [PubMed - indexed for MEDLINE]" > From - http://www.ncbi.nlm.nih.gov/pubmed/20463738 (fromhttp://en.wikipedia.org/wiki/Evolution)
Look how in the following that two Wikipedia contributors (Mike Steel and David Penny) have falsified data from the SAME paper/abstract (abstract by Theobald, DL, also known as Douglas L. Theobald) that I cited above, crediting *themselves* with writing a book or something or other (likely a letter to the magazine that printed Theobald's paper) on the subject of the article/paper on the SAME DATE as the article/paper and linking to Theobald's paper.
From Wikipedia's article Last Common Ancestor at - http://en.wikipedia.org/wiki/Universal_ancestor - last updated 17 Sept. 2010
David Penny and Mike Steel write (notice the quoted material is a partial sentence only and IS NOT CONTAINED in the abstract/paper by Theobald, which is at the top of this post):
"There is strong quantitative support, by a formal test"[1] for the theory that all living organisms on Earth are descended from a common ancestor.[4]"
Note who their sources for this statement are: themselves (#4), and the paper/abstract I cited above (#1). And the PMID numbers in both #1 and #4 are links which lead to the same abstract/paper by Theobald.
Linda 444 ( talk) 19:07, 27 September 2010 (UTC)
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This needs to be updated with respect to some of the evidence points given in the "Evidence of universal common descent". There are elements of this that, while evidentiary, is not true of all current life on earth.
Examples include:
There is plenty of evidence still, of the last universal ancestor; this is just a matter of correcting the article qualifications to be more accurate in view of later discoveries.
This article states that there was an arbitrary choice of codon patterning. I am not an expert, but last I checked, there was evidence that each codon tends to be more attracted to its amino acid in solution than to any other. Also, to describe the universal ancestor as already having 3-base codons etc should be cited in my opinion. Any such organism must have evolved from something simpler, or been put there by an intelligent designer. - Richard Cavell ( talk) 12:11, 19 March 2011 (UTC)
I am baffled by the appearance of a phylogenitic tree based on cavalier-smith papers being presented as the accepted view of the tree of life. It is all but the accepted view. I find the Cavalier-smith papers very interesting and bold, but they must be read in context (the reviewers' comments on his biology direct paper spell it out). Molecular phylogeny may be wrong, but until the consensus is against it, it should be the main view presented. Putting together a cladogram requires a lot of effort and I do not want to summarily delete it, but in most scientific litterature LUCA is not a bacterium, but a bacterium/neomuran ancestor. Most papers that do claim it to be a bacterium place it in the Firmicutes and not with a basal phylum "Chloroflexi" (the phylum does not have a proper name and Cavalier-Smith coined the term Chlorobacteria, but that is not how the system works another example why the papers require a pinch of salt). Therefore should this large tree be transfered elsewhere? -- Squidonius ( talk) 03:49, 1 August 2011 (UTC) Moved here for now: Phylogeny [1] [2]
References
{{
citation}}
: |pages=
has extra text (
help)CS1 maint: unflagged free DOI (
link)
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: Unknown parameter |name=
ignored (
help)
LUCA |
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Notes:
1 Eobacteria
2 Glidobacteria
3 Negibacteria
4 Frankiineae
5 Streptomycetes
6 Arthrobacteria
7 Arabobacteria (Neomura stem from within Arabobacteria)
8 Archaeobacteria
Eurybacteria = Selenobacteriales, Heliobacteriaceae, Fusobacteriales & Thermotogales
Aphragmabacteria = Mollicutes & Erysilothrichia
Terrabacteria: Chlorobacteri, Deinococci, Cyanobacteria, Endobacteria, Actinobacteria & ?Fusobacteria
Selabacteria: Terrabacteria & Hydrobacteria
♠ Strain found at the
National Center for Biotechnology Information (NCBI) but has no standing with the
Bacteriological Code (1990 and subsequent Revision) as detailed by
List of Prokaryotic names with Standing in Nomenclature (LPSN) as a result of the following reasons:
• No pure culture isolated or available for Prokayotes.
• Not validly published because the effective publication only documents deposit of the type strain in a single recognized culture collection.
• Not approved and published by the
International Journal of Systematic Biology or the
International Journal of Systematic and Evolutionary Microbiology (IJSB/IJSEM).
Let's start Auto-Archiving this Talk Page. The Mysterious El Willstro ( talk) 01:45, 30 April 2012 (UTC)
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I removed two points from the features section. If people have objections to this, let's discuss it here :)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
The information in the "Criticism" section can be broadly defined as "Creation Science." These are arguments commonly used to support the pre-conceived conclusion that humans evolved independently of all other organisms on earth. Basically, the author's position is that instead of there being ONE family tree for all life on earth, there are a bunch of different trees and that in some cases(particularly that of humans) the tree is simply linear. While the article should probably contain some general comment to the effect that there are some other non-trivial hypotheses about the exact path to our current biodiversity, it is NOT acceptable for non-NPOV theories outside sphere of accepted science to comrprise 60+% of the article. —The preceding unsigned comment was added by 167.83.10.20 ( talk) 20:15, 11 April 2007 (UTC).
Let us PLEASE not get religious "criticisms" into this article. That should belong in Conservapedia. Let's keep it proper science on this page. — Preceding unsigned comment added by 149.172.153.15 ( talk) 10:29, 22 November 2012 (UTC)
I am removing the "LUCA is refuted" paragraph, it's thinly disguised creationism. The somewhat relevant parts of it, about problems rooting the tree of life, are already addressed in the article via the section on gene transfer.
- Blueshifter 15:26, 29 April 2007 (UTC)
The criticism section smacks of creationist nonsense right from the first sentance. —Preceding unsigned comment added by 12.33.211.29 ( talk • contribs) 09:56, 20 June 2007
It shouldn't automatically be dismissed as 'nonsense'. People need to be open to other viewpoints and interpretations of the scientific evidence. I do understand the rules of needing reliable/verified material for the wiki, though. But people still need to have more respect for other viewpoints. — Preceding unsigned comment added by 98.213.92.109 ( talk • contribs) 05:06, 9 January 2012
Removed unsourced, weasely criticism section. There is no doubt some published scientific criticism - so find and cite it if the section is to be re-written. Vsmith 11:28, 20 June 2007 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I created a paragraph that attempts to list all the properties shared by all independently living organisms (not viruses), based on the assumption that the LUA must also have had these properties. I had lots of fun doing this. It is clearly incomplete; be bold, improve it. Emmanuelm ( talk) 16:15, 11 January 2008 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I added this paragraph. A bit weak, but I think it is interesting. If you delete it, I will not revert. Emmanuelm ( talk) 17:08, 11 January 2008 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
According to the definition of Ur-organism found in its article, there seems to be no need for both articles on "ur-organism" and " LUCA". I am not familiar with the ur-organism concept, but it also seems possible to me that it actually refers to the first instance of life or even the First Common Ancestor (as discussed above), and that the definition listed at Ur-organism is incorrect. Does anyone know anything more about this? Should the two be merged and disambiguation be set up or should the definition of ur-organism simply be rewritten accurately? - Thibbs ( talk) 21:58, 3 May 2008 (UTC)
Later in the chapter he refers to the ur-organism as "a protobiotic form." This source, then, clearly supports the idea that "ur-organism" is a term for the First Universal Ancestor (not to be confused with the First Living Organism) rather than the Last Universal Ancestor. There are a few corroboratory sources from the social sciences or religious scholarship which I would hesitate to rely upon (eg. Rist's paper and Unger's article which was referenced in Google Scholar...). There are also an irritating number of folks online who employ the term "ur organism" to mean "your organism" as in "u take ur organism and put it undr teh microscope." The wiki article, Ur-organism, references Darwin as the originator of the term and I have run text searches on online versions of Origin of Species to no avail. I have not yet run tests on Descent of Man or his other works. I notice that Oparin has also been referenced but I have not yet examined his use of the term (if indeed he has used it at all). Before doing difficult-to-reverse changes to wiki, though, it seems to me that we need more authority than the unreferenced definition found in the ur-organism article. If anyone can find any information on the use of this term it would be very helpful. - Thibbs ( talk) 00:37, 5 May 2008 (UTC)"We envision the Ur-cells as being very simple, whereas the universal ancestor must—by comparison to these—have been quite complex. Thus, the gap between the approach from above and the approach from below must be filled by an evolutionary path from the ur-organism to the universal ancestor. The problem is not simply the origin of life, it is the physical formation of the the Ur-organism and a subsequent evolutionary epoch giving rise to the universal ancestor."
This looks interesting. Info from this source might be good to extend the article with.
"Why Darwin was wrong about the tree of life". New Scientist (2692): 34–39. 21 January 2009.
-- InsufficientData ( talk) 21:47, 25 January 2009 (UTC)
The article at Organism contains material about the last universal ancestor that has been removed from this article, namely whether there is significant scientific debate about the existence of an LUA. See Organism#Was there a universal ancestor?. Should this article mention that there is a minority opinion held by the religiously motivated "intelligent design" advocates? -- Bejnar ( talk) 22:59, 11 December 2013 (UTC)
Are we talking about a species here, or about a single, individual cell? -- 77.7.152.59 ( talk) 02:03, 24 November 2010 (UTC)
References
There appear to be four possible names for this article, and it does not look as though the current one is the most usual. I did a google search (with "-Wikipedia") on the following terms (without the abbreviations), obtaining the following results:
Recent announcements in the media (such as the New York Times article cited in the item above) have all used "LUCA", which may not prove anything, but is suggestive. LUCA also reads as a clear descriptive term, which would be an advantage. Given LUCA's runaway top score, and for these other reasons, I propose that we rename the article, preserving redirects from the other three terms. Chiswick Chap ( talk) 18:07, 13 September 2016 (UTC)
2. Google Trends currently shows Last Universal Ancestor being used more in searches than Last Universal Common Ancestor: https://www.google.com/trends/explore?date=all&q=Last%20Universal%20Ancestor,Last%20Universal%20Common%20Ancestor,Cenancestor,Progenote
The 2 terms have traded places since 2004. I am not certain counting google searches is a scientific approach. I prefer Last Universal Common Ancestor as a more descriptive name. CuriousMind01 ( talk) 23:57, 13 September 2016 (UTC)
This does not indicate whether LUA may once have been a major term or not, but it is certainly far behind LUCA, and is apparently last behind Progenote and Cenancestor also. Chiswick Chap ( talk) 05:57, 14 September 2016 (UTC)
I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Last universal common ancestor's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.
Reference named "IND-20171002":
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help)I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT ⚡ 14:38, 10 October 2018 (UTC)
I want to point out that the base of the tree has nothing to do with the origin of life. Any conclusion that comes from LUCA analysis can not directly touch the orgien of life. In the same way, I would take the results of Willian Martin's group very carefully, if you read the articles, the conclusions are not really well supported. Avazquez-salazar ( talk) 19:03, 24 October 2018 (UTC)
There are many inaccuracies with this article. For example, it says "Only 20 amino acids were used, only in L-isomers" -- but it's pretty well established that LUCA had selenoproteins. Much of the "Features" section lacks reliable sources (16-19 are all from more than a decade ago), and it would be reasonable to rewrite the paragraph (The genetic code was expressed into proteins ... chemical pathways) entirely. I also suggest combining Martin (2016)'s findings with the "Features" section. Allopathie ( talk) 02:53, 31 January 2019 (UTC)
Granted, the first sentence says that LUCA is sometimes called "progenote", but also says that it's a misnomer, so progenote is a different thing and should have its own article or redirect to somewhere else IMHO (perhaps Three-domain system or Darwinian_threshold#Before_the_Darwinian_Threshold). Apokrif ( talk) 16:25, 6 August 2019 (UTC)
In the Uni. of Bristol paper cited in the introduction, they themselves put a hard limit on the age of the LUCA at the date of the Moon's formation (in line with the giant impact hypothesis). It certainly defies credulity that cellular life could survive a collision between planets, given that the Earth's crust would likely liquify and the atmosphere would be briefly composed of gaseous rock.
Recent work on the age of the Moon constrains its formation between 4.40 and 4.45 Ga "A long-lived magma ocean on a young Moon". Science Advances.. This post-dates the 4,519–4,477 Ma range for the LUCA given in the bristol paper by 10's of millions of years at least. It appears that one of these papers (or the GIH) must therefore be incorrect.
Is it worth noting this in the article? As I think this casts significant doubt on the calibration used in the paper.
00A86B ( talk) 17:12, 18 August 2021 (UTC)
I'm not a scientist, just took interest to this subject.
This article describes LUCA as "population" of organisms. Shouldn't it be just an (one) organism? Especially as I saw another Wikipedia write-up alluding to an individual unicellular organism? Vusi Dlamini ( talk) 03:40, 20 September 2021 (UTC)
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)
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)
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)