Talk:Most recent common ancestor/GA1

GA Review

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Reviewer: Philcha (talk) 09:50, 25 July 2011 (UTC)

I'll mark Y comments when I think they're resolved, highlight N any that are unresolved when most others are done, and strike out any of comments that I later decide are mistaken. I'll sign each of my comments, so we can see who said what - please do the same.

I'll mark the review {{inuse}} when I'm working on it, as edit conflicts are frustrating. If you think I've forgotten to remove {{inuse}}, please leave a message at my Talk page. Please free to use {{inuse}} with your own signature when you're working.

I'll read the article through first, then give comments. --Philcha (talk) 09:50, 25 July 2011 (UTC)

Coverage

• Most paragraphs have no citations - see WP:V and GA criteria. --Philcha (talk) 10:42, 25 July 2011 (UTC)
  • You are indeed correct. I will fix them. The existing body of reference support all paragraphs. I usually tag the last paragraph. But I will go through every paragraph again. Fred Hsu (talk) 01:27, 26 July 2011 (UTC)

• This article covers only Molecular phylogenetics, but the term "Most recent common ancestor" and synonyms such as LCA are equally used throughout phylogenetics, including morphological phylogenetic analyses, for example for fossil (e.g. Arthropod#Evolutionary family tree, which includes extinct and extant taxa) and extant taxa for which genomes are unavailable or uncertain or disputed. --Philcha (talk) 10:37, 25 July 2011 (UTC)
  • I think you raise legitimate questions. But I think we need to separate this into several points and address them individually.
    • Does this article address only molecular phylogenetics? I think the answer is no. Note that mtEve is genetically computed. But MRCA of all living humans is not; it is too difficult to determine genetically. Instead, mathematical models and computer simulations are used with aid from historical and archaeological records. But I think your question is a good one. We need to mark relevant paragraphs more prominently with tags such as molecular phylogenetics, etc. to help readers see these differences clearly. Fred Hsu (talk) 01:50, 26 July 2011 (UTC)
    • Morhpological phylogenetics and fossil records. You are right. That isn't mentioned. I will see what I can find on these. Besides the ones you mentioned, do you have more resources on how morphology and MRCA interact, in today's scientific world? I suppose we could mention how evolutionary family tree were drawn/debated prior to genetics as a background discussion? Fred Hsu (talk) 01:50, 26 July 2011 (UTC)
    • MRCA of diffeernt species is underdeveloped. 'MRCA of different species' could, I suppose, use additional non-genetic-based discussion. Perhaps this section could point to additional articles as 'main articles' or 'further information' articles (e.g. Phylogenetic tree). Fred Hsu (talk) 01:50, 26 July 2011 (UTC)

• I question whether this article is needed. The MRCA concept itself is simple (2-3 sentences), especially if backed up with a simple cladogram (see {{clade}} for how to draw one). The examples, where backed with citations, could be included in Molecular phylogenetics and / or Phylogenetics. --Philcha (talk) 10:37, 25 July 2011 (UTC)
  • Is this article needed? This article is needed, and I am hoping that once you read through these sections you will convince yourself of the same. The thing is, most things covered here are covered in depth in their own articles (e.g. mtEve, y-chromosomal Adam, etc). But this article is what binds them all. These concepts are related, and without MRCA to describe how they are related, you will need to replicate the 'glue' in each article. Also note that the time estimates for various types of MRCAs are understood better in the context of other MRCAs. For instance, TMRCA of all living humans is harder to derive than to-to-mtEve. This article is the right place to explain such difference. Fred Hsu (talk) 01:27, 26 July 2011 (UTC)
  • MRCA is a valid concept deserving its own article. See how many pages out there refer to "most+recent+common+ancestor" most recent common ancestor. Do we honestly expect these people to link to other articles instead? Also note how many wikipedia articles, including those in phylogenetics, link to MRCA to help explain the concept of MRCA. Fred Hsu (talk) 01:50, 26 July 2011 (UTC)
  • Is MRCA just a bunch of cladograms? I've generate my share of cladograms such as File:The Ancestors Tale Mammals cladogram.png which I created to illustrate the long tables I populated to summarize chapters from The Ancestor's Tale. Topics described here do lend themselves to cladogram displays, for instance, Haplogroup. But to tear this article apart and sprinkle its remains everywhere does everyone a disservice. Honestly, I am not sure why I even need to defend the need for this article. It should be obvious :) Fred Hsu (talk) 01:59, 26 July 2011 (UTC)

• • I will hold the review for a week to see whether it is then up to GA standard. If it is not up to standard, I will close the review as "not listed". If you disagree, you can ask at WT:GAN for a 2nd opinion, although the original reviewer (me in this case) has the final word. --Philcha (talk) 12:09, 26 July 2011 (UTC)
    • I think you've done a wonderful job pointing out major problems with the article. Unless the article is greatly improved, your analysis (with the exception of 'whether it is needed') is spot on. I'll see what I can do. Fred Hsu (talk) 04:02, 28 July 2011 (UTC)

• • The issues raised already, including missing citations and uncertain relevance, should have been dealt with before a GA review - a GA review is a quality control system, not help in improving articles (except for minor points, and not too many), see WP:WIAGA. In short, the article was nowhere like ready for a GA review. --Philcha (talk) 11:34, 26 July 2011 (UTC)
  • Please stick to the point. Verbose rhetoric with bold headlines is just annoying. --Philcha (talk) 11:34, 26 July 2011 (UTC)
    • I use structural organization and bold style to help sort out issues. Apparently you don't find this useful. You need only state your preference and ask that I follow it. I am a flexible man. Disparaging my sincere replies simply because our preferences and views do not completely overlap is uncalled for. Fred Hsu (talk) 04:42, 29 July 2011 (UTC)

• • • The first issue is whether an article is needed. At present the article largely duplicates the content of such articles as Molecular phylogenetics, Phylogenetics, Cladistics, Human evolution. Most recent common ancestor (with Last common ancestor, MRCA and LCA as redirects to it) may be useful for the few readers who are uncertain that they understand the term. There may be scope for more content directly about the term, e.g. the history of the term. Whether that would be enough to be GA is uncertain. --Philcha (talk) 11:34, 26 July 2011 (UTC)
    • There may be scope for other aspects of the concept, e.g.: the MRCA will generally extinct (possible exceptions are microbes cultured / bred in laboratories); the MRCA may largely a hypothetical construct. --Philcha (talk) 12:09, 26 July 2011 (UTC)
      • You continue to insist that MRCA duplicates content of other articles. But I think you do not see the difference between MRCA and and specific applications involving this generic concept. It almost sounds as if you were saying parent is not needed as an article since it largely duplicates the content of mother, father, family tree and such. Despite what you claim, contents of MRCA is not duplicated in these articles you point to. Fred Hsu (talk) 04:56, 29 July 2011 (UTC)
      • The article as currently stands is directly about the term MRCA. But your suggestions of adding historical aspects and discussion the fact that MRCA will be generally extinct, etc. are very good suggestions. Fred Hsu (talk) 04:56, 29 July 2011 (UTC)

• • You say "note how many wikipedia articles, including those in phylogenetics, link to MRCA". But Phylogenetics uses "most recent common ancestor" without explanation, and Molecular phylogenetics uses neither "most recent common ancestor" nor "last common ancestor" nor other synonyms or abbreviation. I searched at Google Books for "most+recent+common+ancestor"] and I in the first 2 pages I got (excluding books by and for experts): --Philcha (talk) 11:34, 26 July 2011 (UTC)
    • Evolution by Mark Ridley (? the science journalist). P. 424 explains phylogeny, and assumes that the meaning of MRCA is obvious - in a ? high-school textbook, see the "test questions" at end of chapters. P. 5 may the first use of "common ancestor" in this book, and is used without explanation.
    • Human origins: what bones and genomes tell us about ourselves by Rob DeSalle, Ian Tattersall. P. 67 and 111 assume the term. And this looks like a textbook, see the "test questions" at end of chapters (e.g. p. 98)
    • Mammalogy: adaptation, diversity, ecology by George A. Feldhamer - p. 41 assumes the meaning of MRCA while explaining a cladogram
    • Divine engineering: scriptural accounts and scientific truths about the earth's creation are compatible by David N. Brems (apparently from a Creation Science point of view): p. 95 is the start of the phylogenic content; p. 129 uses MRCA without explanation
    • Where do we come from?: the molecular evidence for human descent by Jan Klein, Naoyuki Takahata. This is the simplest I've found, as p. 44-45 differentiates between "common ancestor" and "most recent common ancestor".
      • That Phylogenetics does not wikilink to MRCA is an oversight, not an argument for discarding MRCA. I shall fix it. Molecular phylogenetics is a short article, and it delegates the implications of applying molecular phylogenetics to Phylogenetic tree whose relationship to MRCA is like that of 'family tree' to 'parent'. Fred Hsu (talk) 05:06, 29 July 2011 (UTC)

• • I've not searched Google Books for "last+common+ancestor" or "common+ancestor". You may want to try these searches to see if any actually defines the term, rather than assuming that it's obvious. --Philcha (talk) 11:34, 26 July 2011 (UTC)
  • In Ruppert, Fox and Barnes' Invertebrate Zoology (2004; ISBN ), the index does not show "most recent common ancestor" or "last common ancestor", and the chapter "Introduction to Invertebrates" (p. 1-7) explains cladists without using "most recent common ancestor" or "last common ancestor". --Philcha (talk) 11:34, 26 July 2011 (UTC)
  • I've not searched Google Scholar, as it's for experts, so very probably assumes the meaning of the "most recent common ancestor" or "last common ancestor". --Philcha (talk) 11:34, 26 July 2011 (UTC)
  • You might want to try reliable "popular science" magazines such as Scientific American or New Scientist, which may give a definintion of MRCA or LCA that you can cite. --Philcha (talk) 11:34, 26 July 2011 (UTC)

I think you have spent too much time focusing on what I see as a not-called-for campaign to discredit this article based on your own personal opinion on whether MRCA is needed. This is not part of the GA-review as the policy clearly states. It distracts from your very good opinion on how to improve this article which I highly respect. I formally ask that you strike out all sections on the 'merit' of this article. Thank you. Fred Hsu (talk) 05:13, 29 July 2011 (UTC)

Structure

(sections)

Dead links and DAB pages

I'll check with User:Dispenser/Checklinks and the DAB checker when the content is stable.

Images

I'll check the images when the content is stable.

Lead

I review the lead last, to check that all of it is based on the main text.

Proposed Changes

Clearly this article is not yet GA. Despite our disagreement on 'merit' (which is not part of QA review), I think good ideas came out of the discussion. I will document these below, and work on the article. There is no point in keeping this QA review request alive while it undergoes dramatic surgery. After Philcha strikes out the paragraphs on 'merit', I will withdraw this request. Fred Hsu (talk) 19:21, 31 July 2011 (UTC)

These suggestions should serve as a guide for further editing of this article. And when I try (or someone else tries) for GA next time, we can check off this list of items before actual GA review starts. Fred Hsu (talk) 19:21, 31 July 2011 (UTC)

Most paragraphs have no citations

The existing body of reference support all paragraphs, but these should be explicitly pointed out inline. And more reference may be added in the process as well. Follow up on many hints and links Philcha provided.

Address the difference between MRCA and phylogenetic tree

These are different concepts.

• Highlight the relationship between MRCA and phylogenetic tree clearly, showing how it is analogous to the relationship between parent and family tree (and how it is different whenever applicable - e.g. single gene ancestry vs male/female parental lines).
• Introduce clade and cladogram and discuss how it relates to MRCA

Plug holes in the coverage in the types of MRCAs

Clearly mark paragraphs and sections as addressing different aspects of MRCA and lineage types: morphological phylogenetic, molecular phylogenetics, famly trees (both male and female lines), single genetic markers, etc. These should be compared and contrasted. Methodologies used for different types of ancestry tracking should be clearly described (e.g. historical records vs DNA records vs fossil records).

Specifically, make these changes:

• Expand MRCA of different species. This should point to phylogenetic tree as main article as well.
• Add morphological phylogenetic, and contrast this against molecular philogenetics
• More discussion on how MRCA of all living humans, as well as Patrilineal and matrilineal MRCAs, relate to family tree.

Historical perspectives

Show how the concept of MRCA changed over time. When was it first discussed? Was this concept even entertained in the predominantly Judeo-Christian culture for the most part of the Western history? Was this found elsewhere?

MRCAs are generally extinct at this moment

...with the exceptions of some microbes cultured/bred in laboratories. Some present day organisms do look suspiciously similar to the common ancestor they share with other more differently-looking organisms, but evolution did not stop for the ancient-looking organism (cite living fossils, platypus, etc).

Result - not listed

You still have not addressed the main problems, including:

• No definition of MRCA.
• No check that the content is already in phylogeny and/or molecular phylogeny - a lot of this article's content should be in these other articles.
• Jumps straight into humans. Just 1 species (or genus or family, if including Homo or hominines) of the millions extant.
• Paras with no citations, e.g. only the 2st and last paras of "MRCA of all living humans" have citations.
• The history of the phylogeny of particular species is irrelevant except as examples, so you'd have to show that the phylogeny of a particular species is an example of some principle (e.g. MRCA in sexual and asexual species / groups).

Regretfully I conclude that this article is not of GA standard, and am marking it "Not listed". --Philcha (talk) 08:29, 5 August 2011 (UTC)