Good articleFlatworm has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.
Article milestones
DateProcessResult
February 25, 2009Good article nomineeNot listed
March 15, 2009Good article nomineeListed
Current status: Good article

Comments

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Does anyone have examples of flatworms that have multiple openings to their guts (as is referred to in the page)? --Mperkins 03:44, 12 Dec 2003 (UTC)

This should probably be incorporated into an external link at some point. http://www.pbs.org/kcet/shapeoflife/video/tv_high.html?ep_hunt_explo2_mov_hi 06:30, 7 Jan 2005 (UTC)

Done. But what exactly is the point of the video? Since when does Wikipedia link to videos?Dragix 16:07, 17 April 2006 (UTC)DragixReply

In acoelomate flatworms, now thought to be unrelated to the Platyhelminthes... --unsigned comment

What? Aren't they the same thing? I think this needs changing. --unsigned comment
Josh corrected this on 01:36, 2006 January 7. --TheLimbicOne(talk) 09:57, 26 February 2006 (UTC)Reply

New species of flatworm found: Imogine lateotentare. They have an interesting way of reproduction. http://www.smh.com.au/news/national/what-lurks-beneath--fleshsucking-sex-fiends/2006/01/20/1137734154394.html Since I'm not into this kinda stuff I'll leave it up to others if this actually needs mentioning and if so, how to go about it. --Mais

Pronunciation?

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Is it pronounced "platyhelminteez" or "platyhelmintheez"? Twilight Realm 02:56, 19 April 2006 (UTC)Reply

The latter. Cerealkiller13 05:09, 19 April 2006 (UTC)Reply

Respiration

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like all other animals, flatworms do I may be wrong, but I thought adult cestodes (and many other gut-dwelling animals) were effectively anaerobic.

That looks very likely, but the sources I've seen, including my main textbooks, don't say so. If you know a source, that would be good news. --Philcha (talk) 08:34, 15 April 2010 (UTC)Reply

Feeding

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Does ANYONE know what flatworms eat? I've been trying for ages to find out, and I was a bit dissapointed to not find the answer under the feeding section. Egregius 15:31, 27 March 2007 (UTC)Reply

I read on www.mcwdn.org/Animals/Flatworm.html, that flatworms eat other small worms, insects, and microscopic matter.- Erika

Excretion?

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Platyhelminthes use flame cells for excretion. Perhaps that would be a nice addition to the page? —The preceding unsigned comment was added by 132.236.121.153 (talk) 23:56, 11 May 2007 (UTC).Reply

Hancockanus???

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Is the type of worm that fences with its penis really called Hancockanus? Or is that some sort of sick, perverted, joke?66.157.207.150 (talk) 02:05, 15 January 2008 (UTC)ShokuMasterLordReply

It's had that name since 1876. I presume that someone named Hancock was being honored by the name, and it may well be that the name was applied before the behavior was observed. -- Donald Albury 02:21, 15 January 2008 (UTC)Reply

Plagarism of (not by) Wikipedia!

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I've just been given a book for my birthday, about marine life, called "The Deep" (Margaret Keenan, Taj Books, 2007).

The page on flatworms starts:

The flatworms (Phylum Platyhelminthes, Greek "platy": flat; "helminth": worm) are a phylum of relatively simple soft-bodied invertebrate animals. With about 25,000 known species they are the largest phylum of acoelomates. Flatworms are found in marine, freshwater, and even damp terrestrial environments. A troublesome terrestrial example is the New Zealand flatworm, Arthurdendyus triangulatus, which rapidly colonized large areas of Ireland and Scotland since its unintentional introduction in the 1960s and has since destroyed most of the indigenous earthworms.[citation needed] Most flatworms are free-living, but many are parasitic. There are four classes: Trematoda (flukes), Cestoda (tapeworms), Monogenea, and Turbellaria.

This is an almost exact copy of the Wiki text, and they didn't even remove the [citation needed] tag! (The citation was added to the Wiki article on 14:49, 24 July 2007 Rursus).

I have subsequently checked several of the articles in the book, and they were all almost word-for-word copies of the Wiki articles of the same name. (And more importantly: I checked the article histories and found that the copied text was older than the publication date of the book).

I'll send this info to Wikipedia's copyright team shortly (and possibly to the book's publishers as well). Wardog (talk) 16:53, 9 February 2008 (UTC)Reply

Note that as all text in Wikipedia is licensed under the GFDL, anyone may freely copy and modify the text, even for commercial purposes. The book may be in violation of the terms of the GFDL in that all GFDL-licensed material copied and/or modified must also be made available under the GFDL, i.e., the book must state clearly that the material is licensed under the GFDL. -- Donald Albury 22:12, 9 February 2008 (UTC)Reply

Sources, etc.

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These look useful: --Philcha (talk) 15:49, 23 December 2008 (UTC)Reply

Lead too long and confusing for broad audiences

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Editors, the lead is very big, can this be shortened? see WP:LEAD. Bluptr (talk) 12:16, 21 February 2009 (UTC)Reply

I added a technical template to the page, because the discussion of classification in the lead section is highly confusing, particularly for a broad audience. I would suggest condensing the explanation and leaving the details for the body of the article CameronNemo (talk) 07:06, 27 August 2021 (UTC)Reply

GA Review

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

Here's how this article's content breaks down in accordance with the GA criteria:

  •  N The article is not well-written. It's a jumbled collection of random facts with some semblance of major (1st-level headers) organization, but breaks down a lot within the sections.
  • The article overall needs a very serious copyedit by someone experienced with the manual of style.
Could you explain that a bit more please? WP:WIAGA is quite specific about the narrow subset of WP:MOS that applies. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • The lead section is too long. It should be a clear and concise summary of the article, and should be able to give a good description of the major topic to someone that just wants a brief overview. Instead, it seems like the major points brought up in the lead go into too many detailed tangents and you get sidetracked onto information that really should be moved into later sections of the article.
Nothing be "moved into later sections", as the lead should not contain material that's not in main text.
Para beginning "Some of the turbellarians have very interesting ways of subduing their prey ..." could be cut - it was not in the version I submitted to WP:GAN.
Para about impact of parasitism could do without sentence "Infection of humans by the broad fish tapeworm Diphyllobothrium latum occasionally causes vitamin B12 deficiency," but the rest is important. --Philcha (talk) 00:46, 26 February 2009 (UTC)Reply
  • The description contains good information, and is one of the better sections. I would recommend reversing the order of paragraphs, though. Cover the features common to all classes first, and then put the paragraph on distinguishing features, and put the table at the end. The table should also be connected better to the text -- as right now, it really just stands on its own.
I had a long think about this before I started on the "lower" invertebrates, and adopted a similar approach in Sponge and Cnidaria (both GA now). The problem is that for the general reader all these critters are unfamiliar and look like rather shapeless blobs, where as Arthropods are easily defined ("have chitinous exoskeleton, including jointed limbs") and Molluscs are at least fairly well-known, although if you look at the article the question of distinctive features is rather complex. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • The section header entitled 'major sub-groups' should actually be called 'Classes' (remember, in biological classification, phyla consist of classes, which consist of orders, then families, then genus, then species).
I considered that and rejected it because:
  • Some of the traditional taxonomy of flatworms (classes or whatever and higher level) is now thought to be malformed - acoels are no longer regarded as flatworms, which has come as a relief; and Turbellaria is a dumping ground as all the wholly parasitic clades are now thought to be descendants of a fairly narrow group within Turbellaria.
  • Non-specialist readers will have enough to learn without taking in Linnean taxonomy as well - especially when the traditional taxonomy of flatworms is broken. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • Since most of the classes mentioned in the 'major sub-groups' section have daughter articles, I think it would be better to shorten many of these topics to brief descriptions of the major classes only. Leave specific information about specific genus and species to the daughter articles on that class (although major species should probably be mentioned here).
Can you please be a bit more specific? I think section "Turbellaria" is perhaps the least coherent, because of the taxonomic issues. However I don't see where it does into too much detail. It presents as far as possible general features that are common to the so-called group's members, but it is only reasonable to point out that there are significant exceptions. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • Try to avoid using 2nd and 3rd level headers in the 'major sub-groups' section -- there should only be four subsections here, one for each class. All the extra headers within the section make it very difficult to read and determine which subheading is a major class, and which is an order or family within that class.
I'm not sure why you think it's a problem. For example I think it's an advantage that the TOC shows readers a hierachical arrangement before they get into the details. That gives them an "aerial map" or in the worst case the chance to go look at another artcile if they thinkthis one is going to be too complicated. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • Logic seems to say that a section on 'Classification and evolutionary relationships' should probably come earlier in the article, right after the description and before the section on 'classes'. Biologists usually refer to the classification of organisms as 'taxonomy', and wikipedia seems to favor shorter and more succinct subsection headings. Although reading the content of this section, the content seems to be very disordered within the actual text. It needs a major cleanup.
Without some description of the major sub-groups the section "Classification and evolutionary relationships" would be rather difficult to understand. This type of content usually comes last in relevant chapters of textbooks, and textbooks have been doing this for longer than Wikipedia.
Apart from the sentence about fossils (which I suppose could have been a para on its own, as it's a distinct sub-topic, the messiness comes from the fact that scientifically it's been a mess that only started to be cleared up in the mid-1980s, although acceptance of the proposed solutions only became widespread after several molecular phylogenetics analyses in the last 9 or fewer years. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • The 'interaction with humans' section seems ok. Not sure if I'd call it complete, though.
Why? What significant points does it omit? --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • Remove the pipes '|' from the 'see also' section. Wikipedia convention follows that items listed in 'see also' are simple bulleted lists. Also, many of those links can be removed from the list -- you should only list links to articles that are not mentioned previously in the article. Many of these are used previously.
Done. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
  • I'm kind of neutral on criterion 2 (references), so I won't put a check or X here. Most of the major data appears to be backed up by appropriate inline citations, and citations seem to come from reliable sources. However, there's still a lot of issues with the article's completeness and organization. It seems like two sources (Walker/Anderson & Ruppert/Fox/Barnes) are used a bit heavily through the article, which shift the balance a bit more towards those authors.
These are textbooks, which are necessary as sources in 101-level articles - scientific journals do not consider aspects that have been regarded as "basic" for decades. Being textbooks, these 2 sources avoid controversial views. Adding further textbooks would be a waste of space and time. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
 Y Ok, I can revise this to say that the article probably meets the citation criteria. So this is fine. Dr. Cash (talk) 23:23, 6 March 2009 (UTC)Reply
  •  N The article has many issues with criterion 3. The organization of the article is very poor, making it very difficult to read, and making it very difficult to judge whether it is satisfactorily complete. At present, it looks like the article consists of a jumbled collection of random facts, trying to be organized into some type of an encyclopedia article. This aspect needs a lot of work.
WTF is criterion 3? Spell it out in plain English! --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
Please see WP:WIAGA for a description of the six Good Article criteria, which is what I used to base this review off of. Dr. Cash (talk) 23:20, 6 March 2009 (UTC)Reply
  •  Y Article passes the WP:NPOV criterion. It seems to be fair and balanced from this perspective.
  •  Y Article seems to pass the stability criterion. I don't see any major edit-warring going on, other than some anonymous vandalism.
  •  Y Images pass the GA criteria as they all have appropriate image copyright tags. I don't think that the two CDC images really belong in this article, though, because they're discussing the life cycle of one member of the class, not the class as a whole. They also seem fairly large and complex, and are probably better suited for daughter articles.
The two CDC lifecycle pics are pretty representative of their groups (digeneans & cestodes), according to the pics and text in the textbooks - and the CDC pics are of such high quality that it would be waste of time looking for or trying to produce others. The lifecycles are also essential if readers are to understand how big a problem parasitic flatworms are, and why. --Philcha (talk) 00:46, 26 February 2009 (UTC)Reply

I hope this helps improve the article. Unfortunately, in its present state, it does not meet the GA criteria and can't be listed. Once the issues are addressed, it can be renominated at WP:GAN. Dr. Cash (talk) 00:49, 25 February 2009 (UTC)Reply

I am totally dissatisfied with your performance as a reviewer. You signed up to review this artcile on 5 Feb 2009, and on 23 Feb I had to ask when you would produce some comments - although that reminder is absent from both your current Talk page and its most recent archive. Then after doing nothing for 2 weeks you quick-failed the article. I'm taking this to WP:GAR. --Philcha (talk) 21:28, 25 February 2009 (UTC)Reply
I apologize about the long time it took to review this article. However, the delay in the time it took to review does not mean that I did a poor review, and it does not make up for the serious organizational issues that this article has. If you would like another opinion on this review, it should not be renominated for WP:GAN; you should post it at WP:GAR instead. That way, you'd get more people looking at it. Dr. Cash (talk) 04:06, 26 February 2009 (UTC)Reply
In a private interchange of messages after this, Dr. Cash complained that the classification section was unclear and suggested usng the traditional classification as a framweork, and placing it earlier in the article. Here is the reply I posted at User talk:Derek.cashman (with a couple of typos fixed):
The Linnean-style classification is in a total state of flux at present - if a source came out and said that as bluntly, I'd quote it. As it is, the paper that suggested a redefined and monophyletic Platyhelminthes (excluding acoels and Xenoturbella) only came out in 2008. That doesn't mean it's a novel idea - the first proposal to exclude the acoels was in 1985 (effectively pre mol phylo). At present I see nothing firm enough to be regarded as a consensus view on the Linnean-style classification at the phylum level. The situation is even worse for the "Turbellaria", which traditionally contain both the "oddballs" (acoels and Xenoturbella) and which turn out to be the containing group for all the syncitial parasitic forms, although these have traditionally been assigned to separate classes. Right now the traditional classification is worthless, except to note that many books present it and it's a mess. The biggest problem is finding sources that are forthright about the mess.
If you can present concrete suggestions about how to structure the article better I'd be interested. But Linnean-style classification is not a suitable framework as the article would build it up and then, in the following section, tear it apart.
You're going to have to provide some citations for the Linnean classification system being in a "state of flux at present". I am certainly not aware of such debates -- though I'll admit that I am more of a Biophysicist than a pure Biologist that's interested in classifying organisms day and night. And I'm not really suggesting going through the whole taxonomy down to genus and species! But the infobox refers to Linnean classification, and provides the Domain, Kingdom, Subkingdom, Superphylum, Phylum, and Classes. But the article section refers to 'Major Sub-Groups', which aren't standard -- those sub-groups listed are, in fact, the Classes. What's wrong with renaming the section to 'classes'? Bring the article itself in line with what's being introduced in the infobox, and use the same terminology.
My other beef with the 'Major Sub-Groups' section is with the use of the multiple sub-section headers (Digenea, Aspidogastrea, which are technically under Trematoda; and 'monogenea' and 'cestoda', which are technically under 'Cercomeromorpha'). It's just not easy to tell which is a subsubsection under that subsection, and which is the subsection itself, because the font size difference is too small. It would greatly improve the readability by focusing only on the major subsections and incorporating the subsubsections elsewhere, perhaps only a brief introductory paragraph in the subsection, and include them in the daughter article as its own subsection. Dr. Cash (talk) 20:10, 6 March 2009 (UTC)Reply
(Re the lead:)
The conventional idea of what a lead should be does not work well at the phylum level because there are so many aspects to cover: general characteristics and exceptions to these (of which Platyhelminthes has significant ones); ecological role(s) (often wide-ranging at the phylum level, as in this case); reproduction and lifecycle (vary so much in Platyhelminthes that they are best deal with by sub-group); impact on humans (serious in this case); place in art and culture (thankfully nothing to worry about here). Look at the other phylum-level GAs and you'll see that the leads are longer than usual. Some reviewers just accepted it, some looked hard and decided there was nothing that could be removed without harm, at least one asked for a 2nd opinion. --Philcha (talk) 22:37, 26 February 2009 (UTC)Reply
--Philcha (talk) 04:20, 6 March 2009 (UTC)Reply
The problems with the lead section are one of the main reasons I listed this at WP:GAR, to get more opinions on this. As I've stated before, looking at the talk page, I'm not the only one that has said there's problems with the lead (too long). Overall, I think there's simply too many details in there and it's not really much of a summary of the article, which is what it should be. Dr. Cash (talk) 20:10, 6 March 2009 (UTC)Reply
How many GAs are there about phyla? --Philcha (talk) 22:17, 6 March 2009 (UTC)Reply

GA Review

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This review is transcluded from Talk:Flatworm/GA3. The edit link for this section can be used to add comments to the review.

I'm starting a new GA review of this article. I'll work my way through it, but first I'd like to raise some points concerning the lead.

  1. The lead of an article like this should communicate effectively with an intelligent high school student. The first paragraph is good. I believe the 4th paragraph ("over half of…") should come next, because it gives the information that will be most important to the majority of readers.
  2. The last paragraph of the lead could be omitted -- the lead is longer than it ought to be, as is usually the case of Philcha's articles.
  3. The paragraph in the lead relating to evolution should be simplified so that a high school student can get something out of it. This is really pretty straightforward stuff, but the use of technical terms at every opportunity will make it incomprehensible to non-biologists. If non-jargony language is a bit fuzzy, the fuzz can be clarified in the body.

More to come as I work my way through the article. Looie496 (talk) 17:55, 8 March 2009 (UTC)Reply

Hi, Looie496, thanks for stepping up so quickly. --Philcha (talk)

  • Re the last para of the lead:
    • "the lead is longer than it ought to be, as is usually the case of Philcha's articles" - ROFLMAO :-)
    • I was attempting to find something at least semi-positive to say about flatworms, because the previous para suggests that we'd be better off without them. How about:
      • remove from para 4 (parasitism) the sentence "Infection of humans by the broad fish tapeworm Diphyllobothrium latum occasionally causes vitamin B12 deficiency" as it's the least serious of the illnesses listed.
      • Shorten "The threat of platyhelminth parasites to humans in developed countries is rising because of organic farming, the popularity of raw or lighty-cooked foods, and imports of meat, sea food and salad vegetables from high-risk areas. In less developed countries, people often cannot afford the fuel required to cook food thoroughly enough, and poorly-designed water-supply and irrigation projects have increased the dangers already presented by poor sanitation and unhygenic farming practises."
      • I'd prefer to keep the last para separate from the previous one, as they're about separate subjects: effects of parasitism and flatworms as a possible control for some introduced species, if the cure is not as bad as the disease. --Philcha (talk) 18:43, 8 March 2009 (UTC)Reply
        I'm happy with those changes. Looie496 (talk) 19:40, 8 March 2009 (UTC)Reply
        Thanks, they're in. --Philcha (talk) 17:25, 10 March 2009 (UTC)Reply
  • Re "The paragraph in the lead relating to evolution should be simplified so that a high school student can get something out of it", I'm quite keen on Wikipedia:Make technical articles accessible. However in leads I find myself torn between that and the demand for brevity. It would help if you could identify which terms you think are difficult, and whether you think the wikilinked articles are any help. --Philcha (talk) 18:43, 8 March 2009 (UTC)Reply
  • Would it help to add a little explanation in "Hence the traditional platyhelminth sub-group "Turbellaria", is now regarded as paraphyletic as it contains the contains the entirely parasistic groups that were defined as separate classes"? --Philcha (talk) 18:43, 8 March 2009 (UTC)Reply

Evolution paragraph in lead

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Since I sort of specialize in "popularizing", let me take a shot here:

Flatworms occupy a pivotal slot in the evolution of animals. All animals more complex than jellyfish have bilaterally symmetric bodies, and biologists believe that all of these descend from a common ancestor, the so-called urbilaterian, which appeared near the beginning of the Cambrian period. Before the 1980s, most evolutionary analyses indicated that the urbilaterian was a type of flatworm. More recent analyses based on genetics have suggested that the urbilaterian was actually a member of the subgroup of flatworms called Acoelomorpha, while the other modern types of flatworms are a monophyletic group which all share common descent from a substantially later stage of evolution, the Lophotrochozoa.

Feel free to reject, revise, or whatever. Looie496 (talk) 19:39, 8 March 2009 (UTC)Reply

Your text is certainly nicer to read, but unfortunately it has some problems:
  • The body of the article says nothing about the urbilaterian, and I think adding theories about that hypothetical critter would just complicate the "evolution" section. For one thing, there's quite a debate about whether Urbilateria was very small and simple, like the planula larva of a cnidarian, or relatively large and complex, with a segmented body, a gut and a distinct head that bore sense organs and something approaching a brain (see urbilaterian). I've forgotten the details as I intend to get back to urbilateria later, when I've learned enough about the major invertebrate phyla and about chordates (and possibly echinoderms, because of the chalcichordate hypothesis, although that's now largely discounted). I think the Acoelomorpha theory is a variant of the "small and simple" theory (the WP article on these refers to the authors of one such proposal, Jaume Baguñà and Marta Riutort, whose names I recognise).
  • In addition just sorting out the flatworms is complex enough without venturing into the wider issues of Urbilateria.
  • "near the beginning of the Cambrian period" is ambiguous,as it could mean "shortly before" or "shortly after". Kimberella, from about 555 million years ago and about 13 MY before the start of the Cambrian, was a full-fledged bilaterian; some fossils from 580 million years ago are regarded as full-fledged cnidarians, and this is taken to imply that the split between cnidarians and bilaterians happened earlier (see text and refs at Kimberella). Of course that does not prove that the last common ancestor of all living bilaterians appeared before 580 million years ago - various earlier bilaterian lineages could have died out without leaving modern descendants - but it shows that a lot of research is needed in this area and should be used cautiously. Whatever the outcome, either interpretation of "near the beginning of the Cambrian period" is almost certainly wrong. --Philcha (talk) 20:47, 8 March 2009 (UTC)Reply
In my paragraph I was more trying to get across the level of writing that I think is appropriate in the lead of an article like this, rather than the specific content. I don't any problems with any of the points you bring up, I just hope you can word this using a lot less technical terminology, and using it in a way such that readers who don't know the technical terms can still get the general idea. Looie496 (talk) 00:29, 9 March 2009 (UTC)Reply
I can see a few small tweaks that might help without increasing the length too much, e.g.
Because they do not have internal body cavities, for over a century Platyhelminthes were regarded as a primitive stage in the evolution of bilaterians (animals with bilateral symmetry and hence with distinct front and rear ends). However, analyses since the mid-1980s have separated out one sub-group, the Acoelomorpha, as basal bilaterians, in other words closer to the original bilaterians than to any other modern groups. As a result the remaining Platyhelminthes form a monophyletic group, in other words one that contains all and only descendants of a common ancestor that is itself a member of the group. The redefined Platyhelminthes is part of the Lophotrochozoa, one of the three main groups of more complex bilaterians. These analyses have also concluded that the redefined Platyhelminthes, excluding Acoelomorpha, consists of two monophyletic sub-groups, Catenulida and Rhabditophora, and that Cestoda, Trematoda and Monegenea form a monophyletic sub-group within one branch of the Rhabditophora. Hence the traditional platyhelminth sub-group "Turbellaria" is now regarded as paraphyletic since it excludes the wholly-parasitic groups although these are descended from one group of "turbellarians".
Please let me know what you think of this. If it works for you, I'll patch it in. --Philcha (talk)
I'm basically happy with that. I think "As a result" isn't correct, because that isn't a result of the other thing, and I would suggest saving the material from "These analyses…" onward for the body, unless there is some critical message there that isn't coming through to me. Looie496 (talk) 16:32, 9 March 2009 (UTC)Reply
Re "As a result ..." it is a result - if the Acoelomorpha are included in Platyhelminthes, Platyhelminthes becomes a hopelesss taxonomic mess.
"These analyses…" onward, I think it's necessary to warn readers that "Turbellaria", which still appears in many textbooks, is also a mess.
Meanwhile I've pasted in the revision above. --Philcha (talk) 18:25, 9 March 2009 (UTC)Reply
Oh I see, you were trying to say that the monophyletic status is a result of separating out the Acoels. To me it looked like the sentence was saying that it's a result of the close relationship of the Acoels with the basal bilaterians.
Aaargh! You're right, it's clearer without. Done. --19:25, 9 March 2009 (UTC)

Distinguishing features

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Next section: basically good, but I would make a couple of changes. First, I think the table needs a sentence to introduce it. Second, I think the table should be simplified a bit. The differences between cnidarians and ctenophores are not really relevant to this article, so I would suggest combining the two categories, and removing the first two lines of the table. As it is, they distract attention and make the table harder to read. Also it might be worth saying "(comb jellies)" when first mentioning ctenophores, since they are a rather obscure group. Looie496 (talk) 20:37, 9 March 2009 (UTC)Reply

This table is a train wreck. I would have tried to fix it, but I'm not sure if there's supposed to be a fourth column, if two of the headings should be merged, or if one of them should be removed completely.--24.16.130.76 (talk) 21:29, 11 June 2010 (UTC)Reply

Features common to all subgroups

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Sigh. Having pushed you to shorten the lead, I now find myself having to say that the first paragraph of this section belongs in the lead. I really think it does, though -- it is comprehensive, easy to understand, and extremely informative about the basic biology of these creatures -- for example, it explains why flatworms are flat. I think perhaps this material could simply be tacked onto the first paragraph of the lead, except for the first sentence.

  • "Sigh" - ROFL --Philcha (talk) 23:49, 9 March 2009 (UTC)Reply
  • First para of lead already ends "which restricts them to flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion." I'm not sure adding the rest of the first para of "Features common to all subgroups" would justify the extra length in the lead - believe it or not, I do actually worry about the size of my leads :-) --Philcha (talk) 23:49, 9 March 2009 (UTC)Reply
    I would personally trade this for some of the taxonomy, which is going to be gobblydegook to the majority of readers, but I'll leave it to your judgement. Looie496 (talk) 01:46, 10 March 2009 (UTC)Reply
    I'm torn between giving the reader as much understanding as possible of the "engineering" (which is is basically how I like to present anatomy and functions, if you remember Sponge) and summarising all the main points of the articles' body. If you don't mind discussing this a bit, I'd appreciate it. In para 2 (taxonomy, lifestyle, reproduction) I think I should edit to:
    The eggs of cestodes and trematodes and are excreted from their main hosts. Adult cestodes generally have vast numbers of hermaphroditic, segment-like proglottids which detach when mature, are excreted and then release eggs. Both cestodes and trematodes and both groups have complex life-cycles.
    That would allow for a bit more on basic anatomy. Which item do you think would add most value? --Philcha (talk) 09:17, 10 March 2009 (UTC)Reply
    Let me try to clarify what concerns me. In the 2nd paragraph of the lead, the first sentence has a complex structure and uses four very difficult words, Turbellaria, Cestoda, Trematoda, and Monogenea (not to mention planaria). The reader, in order to read further, has no choice except to stop here and spend a couple of minutes trying to memorize these difficult words. Most readers won't do it -- they'll either go away, or start skimming. If they start skimming, they probably won't start reading again until the 4th paragraph, where the topic sentence is understandable. The net result is that the 2nd and 3rd paragraphs are only in the lead in form, not in function -- readers won't be able to handle them until they've read enough of the body to familiarize themselves with the difficult words. I think there ought to be some way to improve this situation, but I don't want to try to impose a particular solution on you. Looie496 (talk) 04:25, 11 March 2009 (UTC)Reply
    If I ever start a quotes book, I'll include "The net result is that the 2nd and 3rd paragraphs are only in the lead in form, not in function" - it certainly makes your point :-)
    The problem is that these organisms are not already well-known to the general public, so there are no easily recognised common names - and the reduced awareness of parasitic flatworms as a health issue doesn't help. I've tried to give readers informal descriptions as alternative hooks by which to remember the outline when they reach the details in the main text. I admit that makes the sentence structure complex. The only alternatives I can see right now are:
    • List the names in one sentence, then use a separate sentence to describe each group briefly. This retains the problem you raised, that the lead sentence is daunting.
    • Break it down as a bullet list, where each item starts with the name, followed by brief description. The actual phrasing woudl be similar to the current one, but the list format would make it easier to take in both nam eand outline at a glamce (I'll spare you "Users want to scan, not read"). Anywhere but Wikipedia I'd do that, and I think it's reasonable per Wikipedia:Embedded list. Unfortunately an awful lot of editors are paranoid about lists (my first edit to correct some actual scientific errors in a paleo article was reverted on the grounds that it used a bullet list; a couple of people are still not on my Xmas card list). So if I use a list there's a serious danger that some style Nazi would re-formulate it as prose - and such editors quite often are more concerned with showing off their self-proclaimed prose skills than with readability for non-specialists, so the result might be worse than the current situation.</rant>
    • I could finesse the list issue by presenting the same info as a table - the style Nazis don't seem to have realised that lists and simple 2-col tables are equivalent (you never read this, and I didn't write it) - but esthetically I think that would be over the top.
    Can you suggest any other approaches? --Philcha (talk) 08:50, 11 March 2009 (UTC)Reply
    I took a shot at this myself, trying to use parallelism to make the organization a bit easier for readers to grasp. As always, please revert back if you don't like it. Looie496 (talk) 23:06, 12 March 2009 (UTC)Reply
    Fine by me, thanks. --Philcha (talk) 23:28, 12 March 2009 (UTC)Reply

In the paragraph "Most platyhelminths…", the "since" in the 2nd sentence makes it into a just-so story, and oughtn't to be stated that way (although it's hard to see how it could be wrong).

In the 4th paragraph, "level of concentration" is redundant -- concentration is itself a type of level. This phrase is used twice.

In the 5th paragraph, perhaps clarify that the head end is the end where the mouth is located. (It could be taken as the end where the nervous system is concentrated, which would make this circular.) Looie496 (talk) 20:58, 9 March 2009 (UTC)Reply

  • The head is also where sensory organs are concentrated (eyes; statocysts in some species), and that's how one identifies the head from the outside (w/o dissection). To make matters worse, tapeworms have no mouths and absorb nutrients through their syncitia. --Philcha (talk) 23:49, 9 March 2009 (UTC)Reply
    The majority of readers won't know the difference, but for readers who know what protostomes and deuterostomes are, I think it might be a tiny bit helpful to clarify what "head" means here, in whatever way is most suitable. Looie496 (talk) 01:46, 10 March 2009 (UTC)Reply
    Are you suggesting such readers might conclude that deuterostomes do not talk out of their mouths?
    Seriously, it's difficult to define "head" simply and briefly. For example Ruppert, Fox & Barnes show a pic (p 227) of a grazing "turbellarian" with the mouth 25% of the way back on the underside, and later say of "turbellarians" (p 236) "The mouth commonly is located on the midventral surface, but may be situated anteriorly, posteriorly, or anywhere along the midventral line, depending on taxon". One of the difficulties about this topic is that, even if you dump the acoels, the only flatworms that stick to any kind of rules are the syncitial parasite taxa. --Philcha (talk) 09:17, 10 March 2009 (UTC)Reply

Major sub-groups

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Turbellaria: The only issue I have with this section is that I think it would be good to restate that the Acoela are now known to have a completely different phylogeny than the others. This message is present in earlier parts of the article but it wouldn't be hard for a reader to have missed it. The other thing is that if you are going to mention both planarians and seriates, you should say somewhere that planarians are seriates.

Trematoda: I suggest defining "holdfast" briefly in the article -- the word is used multiple times and will probably be unfamiliar to most readers.

Digenea: You might consider adding a text paragraph to recap the story from the figure. This snail-to-fish-to-land-animal-to-snail is so amazing that it deserves to be fully spelled out. Also I think it is worth mentioning that schistosomes belong to this group. Looie496 (talk) 04:08, 11 March 2009 (UTC)Reply

  • I bottled out on describing the digenean lifecycle as it's so complex - and varies a little between genera (especially in the stages hosted by molluscs - Walker & Anderson in Anderson, pp 73-75). The "typical" one has about 5 stages (eggs, miracidia, cercariae, metacercariae, adult; I think 7 is the record) depending on the sequence of hosts the intermediates stages encounter, some of the stages are specific to certain types of host, and one of the mollusc-hosted stages produces multiple members of the next stage, so strictly it's a 2 generation lifecycle. The textbook I've used most widely titles the relevant section "Life cycle examples" rather than the more confident ""Life cycle" (Ruppert, Fox & Barnes, p 255). Explaining all this would add between 25% to 50% to the length of the section - maybe more. IMO the diagram does does a better job of expressing this intelligbly at this level of article, and the details should be in Digenea - but I'm not volunteering, as it would introduce terms for each type / subtype of intermediate stage, and I think it would be necessary to summarise their names, corresponding intermed hosts, and reproductive capabilities in a table; as well as using the same diagram. --Philcha (talk) 08:01, 11 March 2009 (UTC)Reply
  • Good point about schistosomes, but I think it's better dealt with under "Parasitism", as that's where they get mentioned by name. How would you like "The disease is caused by several flukes of the digenean genus Schistosoma", ..."? --Philcha (talk) 08:01, 11 March 2009 (UTC)Reply

References

  1. ^ Cite error: The named reference WalkerAnderson2001PlatyhelminthesInAnderson was invoked but never defined (see the help page).
  2. ^ Klaus Rohde (2001), "Platyhelminthes (flat worms)", Encyclopaedia of Life Sciences, doi:10.1038/npg.els.0001585

The Lead

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I think that the lead is very big, can the amount of information in the lead be brought down or made brief? (See WP:LEAD )--Bluptr (talk) 09:07, 12 March 2009 (UTC)Reply

Various GA reviwers have decided to WP:IAR re the leads in articles on whole phyla, as the lead in such articles needs to cover what is often quite a disparate range of animals, sometimes with the full range of lifestyles; ecological significance, if any; interactions with humans, if any (quite important w flatworms); evolutionary history; and significance in human culture(s), if any. All of these are magnified by the fact that the article is covering a huge range of species, some of which might be sessile while others are active (molluscs and chordates possibly have the greeatest variety in this respect). The lead is supposed to summarise all the main ponts of the article. On the other hand WP wants leads to be as easy to understand as possible, which often means using phrases rather than shorter but less widely-known technical terms.
However if you can find ways of making the lead more concise without sacrificing any of these objectives, that would be very helpful. --Philcha (talk) 12:51, 12 March 2009 (UTC)Reply

Classification and evolutionary relationships

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First item: it seems to me that the first paragraph ought to make clear that synapomorphies are critical for "classical classification" but don't come into play in genetically based approaches, which have been taking over.

The mol phylo approach is also based on cladistics, so it looks for synapomorphies, but they're genetic rather than morphological - and they use the same software (until recently PAUP was the dominant software). Morphological analysis is still significant. For example the first proposal to eject the acoles from Playhelminthes was around 1985 and was based on morphologial analysis; and end of 2nd para of Sponge#Family_tree cite s a genetic and a morhpological analysis, both from 2007. --Philcha (talk) 00:12, 13 March 2009 (UTC)Reply

Second item: near end of 2nd paragraph, "agreed that both are more closely related to cnidarians (jellyfish, etc.) than other bilaterians are". I think this is wrong -- all bilaterians should be equidistant from cnidarians. Otherwise cnidarians would be a sister group of acoelomorpha.

In 2nd-to-last paragraph, might be worth saying that the sister group, Gastrotricha, are "tiny aquatic worms that feed on microalgae, bacteria, and protozoans", or something like that.

Last paragraph: if the traditional turbellarians include the acoelomorpha, they are paraphyletic for more reasons than the sentence states. Looie496 (talk) 23:42, 12 March 2009 (UTC)Reply

Most of the presentation assumes that acoelomorpha are not platyhelminthes - that's why I dealt wiuth that first. The point is that even without acoelomorpha, "Turbellaria" is paraphyletic.
PS I'm tired and the other 2 items need a bit of thought - I'll respond tomorrow. --Philcha (talk) 00:12, 13 March 2009 (UTC)Reply

GA passed

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I'm passing this article for GA now. Although there are still improvements that could be made, I am satisfied with its current state enough to feel no qualms about passing it. Looie496 (talk) 01:20, 15 March 2009 (UTC)Reply

Evidence or citation regarding claims about organic farming and flatworm parasite risk?

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Does anyone have evidence or citations for the claims in the posted statement:

The threat of platyhelminth parasites to humans in developed countries is rising because of organic farming, the popularity of raw or lighty-cooked foods, and imports of meat, sea food and salad vegetables from high-risk areas."

To me this statement infers negligence towards public health on the part of organic farming that seems out line with my understanding organic farming practice. Given that organic farming predates what we have come to now call conventional farming, one would not only have to accept that the intent of conventional farming was primarily to prevent human disease (instead of other more prevalent reasons like boosting crop yields with synthetic fertilizers and pesticides), but also that returning to organic farming is to willfully depart from this lofty ambition.

Don't get me wrong, that isn't to say that there is some underlaying logic to justify the statement. If conventional farming practice has managed to reduce the risk of platyhelminth parasitesto humans, then returning to organic farming may call a return to the risk - then again, it may not if you consider our more increased understanding of food handling and preparation since the rise of conventional farming. Who's to say? Where is the evidence? The statement needs support to uphold this logic.

Without including the evidence or a citation to support this statement as it is currently worded basically amounts to opinion and without the objective detachment of scientific evidence, or even a disclaimer of supposition, it exposes this scientific article to the politics of heated public debate over organic vs conventional.

Frankly, I (obviously) have strong opinions on the subject of organic farming and I took offense to the statement - a scientific article shouldn't offend me and get me all fired up. Heck, I was trying to learn about worms so I can better understand vermi-composting, not looking for debate. If the statement has scientific backing, please include it.

Thanks. Moose Meat Stew (talk) 09:01, 8 March 2009 (UTC)Reply

The refs are in the article, are from impeccable sources, and are freely available online. --Philcha (talk) 09:41, 8 March 2009 (UTC)Reply

I'm sorry, my aim is not to criticize credibility, so much as it is to suggest that the current incarnation of this article does not making it easy for the reader to investigate the source for this particular assertion against organic farming, and thereby determine the context from which the statement was drawn, due to the lack of a direct and specific citation which requires the reader to wade through a list of twenty-five references, five further readings, and six external links for more information. I'd be more than happy to review the source to draw my own conclusions around organic farming and parasitic risks if only someone were able to provide assistance in narrowing down where the idea came from since I have little desire to become a subject matter expert on the complete biology of flatworms.

At the risk of beleaguering the point, when reading the statement through the lens of "pro-organic", the suggestion that organic farming increases threat of parasitic flatworm infection makes as much sense to me as if I were to suggest there were is an increased risk in ankle injury due to walking. I know for a fact that people have been walking for a long time and that this practice in and of itself should not increase injury risk over what it has been at some point during walking history. My statement would be down right inflammatory if referenced as a reason why people should get back in their cars instead of walking. Organic farming was all there was long before the invention of pesticides, we just didn't have any need to call it anything other than farming at that time. The statement suggests to me that if we were to revert to only organic farming that parasitic flatworm infestations would rise unchallenged as there is no mechanism in organic practices to deal with it. That seems narrow-sighted.

Without the details to frame this otherwise anti-organic comment, or at least specific citation to explore for those of us so piqued, there is a risk that this (probably innocent) statement could be misused in contexts outside of the scope of this article. My imagination conjures up someone out there citing this article to support the outlandish claim that organic produce will give you worms. I'm merely suggesting that with the aim of objectivity, either the idea be expanded to include the details, the wording be reconsidered, or the source for that specific assertion be indicated directly at the end of the sentence for the benefit of the reader.

I don't think this is an unreasonable suggestion. Moose Meat Stew (talk) 22:59, 8 March 2009 (UTC)Reply

Most Wikipedia articles don't use extensive references in the lead. If you look in the body, at Flatworms#Parasitism, you'll see clearly that the reference is the Northrop-Clewes paper, which has a section on the perils of organic farming. Looie496 (talk) 00:44, 9 March 2009 (UTC)Reply

Thank you for the direction (and you patience). I apologize if my understanding of the referencing practice in the lead is a bit novice.

I have (now) read the Northrop-Clewes paper section about "the hidden menace" of organic farming. They are absolutely correct in that spraying feces on your field will make you sick by spreading all sorts of baddies. Unfortunately their broad-stroked swipe at organic farming neglects some key points.

1. Properly composting manure kills most pathogens and parasites through the heat generated by composting. Infections would be more likely from improperly composted or handled manure than the simple fact of it's use.
2. Spreading of manure is not isolated to organic farming and organic farming does not have to depend on manure. The two are not codependent. I live in a rural community and can attest to the fact that non-organic farmers still spread manure.

Although they didn't delve into it, Northrop and Clewes actually touch on the problem in the header of the passage itself. "The organic food revolution in industrialized countries -the hidden menace" alludes to the fact that an improper marriage of organic and industrial practice can create problems. Unfortunately, the passage seems to promptly takes a tone against organic farming and carries this position though the article going so far as attacking organic farming as "turning back the pages of history" and it even makes a call to ones senses as an argument. I mean, really, come on. Can the fact that manure stinks be a scientific argument against it? I don't see anyone perfuming their house with synthetic fertilizers and pesticides. Organic practices do not all come from the days of lore and can, with some ingenuity and creativity, be adapted to the demands of industrial output. While Northrop and Clews do make a point about manure as a potential carrier, I can hardly consider their passage a definitive account of organic practice.

There is a good book by Michael Pollan called "The Omnivore's Dilemma" that covers the implications of industrial food production, organic food production, and the practice of hunting and gathering. It goes a long way to exposing some harsh misconceptions about how we grow, gather, transport, think and feel about our food as well as exploring the impact our efforts have on both the environment and our communities. He exposes some prime examples of where organic meets industrial and shows where it works and where it doesn't. If you have some time and the interest, it is a great read.

May I suggest that the passages regarding organic farming in this article be reworded somehow. Blaming organic farming simply carries over whatever sentiment Northrop and Clewes hold against organic farming. I don't think the idea of manure as a carrier is without merit, but perhaps this article should simply addresses the use of improperly prepared manure-based fertilizers as it would be more scientifically complete and less biased while side stepping the entire organic-industrial debate (and the likes of people like me) altogether.

Thanks.Moose Meat Stew (talk) 04:47, 9 March 2009 (UTC)Reply

I've avoided the more extreme wording of some sources and simply noted that there's a problem. It's been known for at least a century that using human feces as fertiliser spreads internal parasites - AFAIK Victorian public sanitation saved at least as many lives as Victorian medicine. How the spreading of parasites might be dealt with should be covered in Organic farming or possibly Public health. A strategy that occurs to me is thorough composting before muck-spreading, as the heat at the centre of a large mass of compost kills most small organisms as well as weeds and their seeds; and the compost would have to be enclosed, to prevent seagulls and other foragers from transmitting unkilled parasites. If / when the issue is covered at Organic farming or wherever, I'd be very happy to incorporate into Flatworm a very brief note on this and a "Further information" tag linking to the appropriate section of Organic farming or wherever. --Philcha (talk) 11:06, 9 March 2009 (UTC)Reply

evidence about organic farming II

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Firstly, to resolve this issue. Let's invoke fair use and paste the authors passage concerning organic farming as the article is not freely available for discussion.

The organic food revolution in industrialized countries -
the hidden menace
In parallel with increasing public anxiety over the emergence of
genetically-modified foods in industrialised countries has been a trend
towards ever increasing public demand for organically-grown produce.
In commercial response, most, if not all, of the major food retailers in
the UK have now a stated policy of removal of genetically-modified
foods from their shelves with an increase in capacity for organic
produce. While such trends may appear to be eco-friendly on face value,
there are potential hidden dangers for consumers. Over the past 20
years, the use of artificial fertilisers on farmland to facilitate an intensive
agriculture focused on the rapid production of uniform products for
mass consumption has led to a massive reduction in the use of organic
manures on the land. During the same time period, intensive usage of
anthelmintics in domestic livestock for the same purpose of maximising
productivity has led to massive reductions in parasite burdens. Taking
both factors into account, one can see the reason for the virtual elimination
of parasitic disease as a major clinical problem in industrialised
countries. However, changing practices for economic or social reasons can
provide parasites with new opportunities for transmission which they will
exploit with gusto. After all, this is what evolution has gifted parasites to
do. While little evidence exists of the nutritive benefits of organic produce,
the change from the relative sterility of inorganic farming to an organic
culture system may turn back the pages of history to the time when
parasitic disease in the population was the norm. After all, it is a fact that
under natural conditions, all vertebrates (including man) are probably
universally infected with at least one helminth parasite - is this really to
where we wish to return? How many of us who live in the countryside or
who drive through such en route to our places of employment have not
been subjected to mighty olfactory attack as farmers spread 'muck' on
their fields? Such spreadings usually have large flocks of attendant gulls,
many of which defecate over a wide area including in our parks, playing
fields and reservoirs. The factors are thus already in place for the
resurgence of helminth parasitic disease - one can be sure that it remains
a matter of when, rather than if, this will occur.

Secondly, let's analyze what, if any proof is presented therein for the claim being made herein...that's right there is no actual emperically based research being cited to bolster this authors OPINION. The claims of these authors with regards organic farming rest on data that does not exist. It is no wonder that this article has only been cited 8 times in 10 years, it's fringe. 141.39.166.159 (talk) 17:31, 28 July 2009 (UTC)talonxReply

It's in British Medical Bulletin, i.e. in a reliable source. If you can produce good sources stating that organic farming does not increase risk of parasites, cite them and we have a debate that the article needs to summarise. Until then, the text stays as is. --Philcha (talk) 20:53, 20 September 2009 (UTC)Reply

Recomended Purge

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I recomend a purge of all claims relating to the shaw article (currently citation number 20). 141.39.166.159 (talk) 17:35, 28 July 2009 (UTC)TalonxReply

Not going to happen. If you wish to contest the points that are based on Northrop-Clewes and Shaw (2000) "Parasites" you will have to find at least one good source that presents opposing views - see WP:Vand [[WP:RS]. --Philcha (talk) 20:52, 28 July 2009 (UTC)Reply

Alternative spelling

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In many literature I find it written as "Plathelminthes", without the "y". I include it in the first paragraph, if there´s no problem with it. --Feministo (talk) 11:38, 27 January 2010 (UTC)Reply

Domain Eukarya

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Domain Eukarya isn't required here. It just clutters up the infobox. 78.151.23.110 (talk) 21:10, 11 February 2010 (UTC)Reply

Format error

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Hi,

The table seems to be making the page look messed up, but I have no idea as to how I can fix it. Could someone care to fix it please? Thanks! Devrit 00:33, 12 December 2010 (UTC)Reply

Never mind i managed to fix it myself thanks anyways Devrit 00:38, 12 December 2010 (UTC)Reply

Taxonomy

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It had long been recognized that this classification was artificial, and in 1985 Ehlers[9] proposed a phylogenetically more correct classification where the massively polyphyletic "Turbellaria" was split into a dozen orders, and Trematoda, Monogenea and Cestoda were joined in the new order Neodermata. However, the classification presented here is the early, traditional, classification, as it still is the one used everywhere except in scientific articles.[3] Isn't this about the opposite of what we are supposed to do on wikipedia? If we were writing this encyclopedia on vellum in the XVII century, would we say that the Sun revolves around the Earth because heliocentrism is something that is only found in scientific books?? My question is: can I fix the taxonomy, or am I going to be instantly reverted by some well-meaning pest that thinks I confuse children and geezers that studied before the discovery of DNA? complainer (talk) 10:08, 28 February 2012 (UTC)Reply

I agree with you. The classification should be presented in its current form. A section or paragraph talking about the old classification in four classes would be necessary, but the current, phylogenetic classification is the most important. Piterkeo (talk) 16:04, 02 March 2016 (UTC)Reply

Invertebrates?

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Hi all, There seems to be an error in the infobox. It says "Unrecognised rank: Unrecognised rank: Phylum- Invertebrates". Did someone edit the template? It doesn't seem to just be on this page. Anyway, I'm not really experienced with template editing, so I'll leave it for one of you fine fellows. Thanks, Wham Bam Rock II (talk) 18:03, 1 May 2012 (UTC)Reply

edit

--Gary Dee 18:38, 21 July 2013 (UTC)Reply

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'Is they, or isn't they'? 😉

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(Pardon my jokey title, but, I've a question; I'm not a person who really knows much about flatworms, but, this seems to be incongruous

In the 2nd paragraph is the foloowing sentence; ...since the turbellarians have since been proven not to be monophyletic, this classification is now deprecated....', but, shortly below is the following sentence: '...The remaining Platyhelminthes form a monophyletic group..


Isn't this contradictory? Just wondering...[[User:UNOwenNYC

There is no contradiction at all. Turbellarians are not monophyletic because the parasitic flatworms evolved from them. "The remaining Platyhelminthes" is not the same as "turbellarians". Historically the flatworms were divided in 4 groups: Turbellaria (Acoela, Nemertodermatida, Catenulida, Polycladida, Tricladida, Macrostomida, Rhabdocoela, Prolecithophora, Lecithoepitheliata, Proseriata), Cestoda, Trematoda and Monogenea. This classification is deprecated because Turbellaria is not monophyletic. The phylogenetic classification includes two groups: Catenulida and Rhabditophora (Polycladida, Tricladida, Macrostomida, Rhabdocoela, Prolecithophora, Lecithoepitheliata, Proseriata, Cestoda, Trematoda and Monogenea). And Acoela and Nemertodermatida are not flatworms at all. — Piter Keo (talkcontribs) 21:50, 11 February 2017 (UTC)Reply

Flatworm fossil range should be pushed back

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According to a recent molecular study, flatworms originated 839 million years ago. OP-MOLB150055 835..845 (silverchair.com) PhiPedia (talk) 18:30, 22 November 2023 (UTC)Reply

That date sounds erroneous, as animals had not yet diverged from sponges. That, and the fossil range is for the age of the earliest fossils, not molecular evidence.--Mr Fink (talk) 01:30, 23 November 2023 (UTC)Reply