Talk:Nemertea/GA1

--Philcha (talk) 00:22, 4 April 2011 (UTC)

GA Review

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Reviewer: Looie496 (talk) 23:27, 18 February 2011 (UTC)

I'm delighted to have a chance to review another Philcha phylum article, although I have to say this one has more problems than the others I have done. Even so, after an initial pass it looks like it is within shooting range. One thing it clearly needs is a thorough copy-edit -- although I can do some of this as I go through it. I'll now list the first issues that I see:

• The lede has unnecessary detail in some respects. In particular, the 2nd and 3rd paragraphs are so dense with detail that they are likely to make many readers flee in terror before getting to the more important information that comes later in the lede, such as the number of species, variety of habitats, and behavioral habits.
  • Hi, Looie496, it's nice to see you again.
  • I've made the lede shorter. --Philcha (talk) 10:48, 19 February 2011 (UTC)
  • I still think the unique features of Nemertea are the rhynchocoel (for itself, and the position of the brain) and the proboscis. Otherwise they'd look like many other Lophotrochozoan "worms". And the rhynchocoel and proboscis need to be set in the body architecture. --Philcha (talk) 10:48, 19 February 2011 (UTC)
    • I agree with you, and I didn't intend to say that all that material should be removed from the lede -- just that it should be simplified to be more readable. Looie496 (talk) 17:26, 19 February 2011 (UTC)

• I agree that citations should be minimized in the lede, but I feel that when specific numbers are given, a source should be supplied, even if the information is repeated later.
  • Added source for length. --Philcha (talk) 10:48, 19 February 2011 (UTC)

• Many have patterns of yellow, orange, red and green. Patterns of coloration, is this? And should it be or instead of and?
  • "and" is right - Commons has only the drab lead pic, but see "Introduction to the Nemertini". --Philcha (talk) 10:48, 19 February 2011 (UTC)

• I feel that most of the material in the 2nd the 3rd paragraphs of the lede would be much more comprehensible if presented in conjunction with a cross-sectional diagram. Since the lede isn't a suitable place for such a diagram, can the majority of the material be moved into the description section?
  • I've responded on the 2nd para of the lede above. I've shortened tht 3rd para and re-ordered it so the CNS is first, as the brain position is an other unique feature of the pylum. --Philcha (talk) 10:48, 19 February 2011 (UTC)
    • Not completely satisfied yet, but I'll strike this point and follow up below. Looie496 (talk) 18:39, 19 February 2011 (UTC)

• The outermost layer of the body has no cuticle. In animals with a cuticle, does one say that the outermost layer has a cuticle or that it is a cuticle? In other words, should the cuticle itself count as a layer?
  • IMO either would be correct in terms of English. Here there's no cuticle, and cuticle is generally non-cellular. So I like how it's written here. --Philcha (talk) 10:48, 19 February 2011 (UTC)
    • Okay. Looie496 (talk) 18:39, 19 February 2011 (UTC)

• Most species are gonochoric (the sexes are separate), but all the species are hermaphroditic. This sentence contradicts itself. Later in the article it says that the freshwater species are hermaphroditic, not all species. I hate the word gonochoric -- can't the article just say that they have distinct male and female sexes? Most of the rest of the 5th paragraph is too detailed for the lede.
  • Copyedited to In most species the sexes are separate, but all the all the freshwater species are hermaphroditic (how did I miss that?) --Philcha (talk) 10:48, 19 February 2011 (UTC)

• In the last paragraph of the lede, the sentences are in almost a random order. The information is all okay for the lede, I think, but this needs to have some organization imposed on it.
  • You mean the fossils (none), taxonomy and phylogeny? Fossils first because evidence (if any) overrides theory. The next part is relationships within the phylum. The last 2 sentences are a level up, about their relationships with other, including the relationship with flatworms (some readers will see old books that state that nemerteans are closely related to flatworms and that both are relatively "primitive" acoelomates) and with Lophotrochozoa (too complex for general readers, just a pointer for zoology students. --Philcha (talk) 10:48, 19 February 2011 (UTC)

I'll continue going over the remainder of the article presently. Looie496 (talk) 23:27, 18 February 2011 (UTC)

• I took the liberty of moving the paragraph about the basic biology into the first paragraph, because it seemed to greatly improve the flow. Revert if you feel a need to, but I really think the lede works better that way.
  • First, thanks for copyediting "Most nemerteans are slow-moving marine animals ... are sold as fish bait". --Philcha (talk) 22:31, 19 February 2011 (UTC)
  • At first I liked the new position of the passage in the lede. But then I read on, through the past about the rhynchocoel and proboscis, which are 2 or the unique features of the phylum. On the other hand, "Most nemerteans are slow-moving marine animals ..." sounds like lots of generic worms. So I still prefer the original placement. --Philcha (talk) 22:31, 19 February 2011 (UTC)
  • And I prefer the part in the lede about the CNS to be a separate para, to emphasise the position of the brain, the other unique feature. --Philcha (talk) 22:31, 19 February 2011 (UTC)

• Concerning the paragraph about the structure of the body, how about trying to organize this on the theme of how nemerteans differ from other types of "worms"? I still feel that the paragraph has too much detail, but one way or another it really needs to have some sort of structure imposed on it.
  • The rhychocoel and proboscis are unique features, but as far I know no source uses "unique". On the other hand sources say the brain lies round the rhynchocoel near its front end, while the brains of most protostome invertebrates encircle the foregut.

• I mentioned this before, but I'll suggest it again in a more isolated way: would there be any possibility of getting a drawing of what the generic nemertean body looks like in cross-section?
  • You mean replace the current lead pic? The double pic intentionally spanning sections "Body structure and major cavities" and "Proboscis and feeding" show the significant differences between Anopla and Enopla - and the Enopla one is only a "typical" member of that clade, as Polystilifera has a significant difference while Bdellonemertea are very different. I've seen a pair of pics with the proboscis retracted and partly everted, but: this applies only to the Anopla, as the proboscis of the Enopla everts only enough to clear the stylet(s); the Bdellonemertea, although classify as part of Enopla, have no proboscis; no source I've seen says where the proboscis attaches to the inside of the rhynchocoel (I guess only at a ring in the front of the rhynchocoel). So I think any pic of a "typical" nemertean would just cause trouble. -Philcha (talk) 22:31, 19 February 2011 (UTC)

Fossil record

I'm going to take sections out of order; I hope that's okay.

• As nemertea are completely soft-bodied.... Isn't the stylet a hard part of the body? I would like to do a copy-edit, but need to get this point clear first.
  • Stylets are calcium carbonate, so hard, but no fossilised ones have been found (or recognised?) so far. --Philcha (talk) 09:34, 20 February 2011 (UTC)
    • The question is whether a stylet counts as part of the body. If it does, then nemertia are not completely soft-bodied. Looie496 (talk) 19:27, 21 February 2011 (UTC)
      • Introduction to the Nemertini says "The fossil record of nemertines is extremely sparse, as would be expected for this completely soft-bodied group. The stylets of nemertines would be expected to survive as fossils, since they are made of the mineral calcium phosphate, but none have been reported so far." Also only some nemerteans have stylets. How about "The fossil record of nemertines is extremely sparse, as the only hard parts would be stylets of some groups, but no stylets have been reported so far." --Philcha (talk) 22:02, 21 February 2011 (UTC)
        • Edited. --Philcha (talk) 11:32, 18 March 2011 (UTC)

Family tree -- within Nemertea

• There is no doubt that the phylum Nemertea is monophyletic (meaning all members of the clade are descendants of one ancestor that was also a member). I don't think this is a correct definition of monophyletic -- in addition to all members of the clade being descendants of a common ancestor, it also means that all descendants of that ancestor are members of the clade. In other words, it also requires that no species belonging to any other phylum be a descendant of the "urnemertian". This being the case, "there is no doubt" seems too strong to me.
  • I'd forgotten my concise explanation that I used to use :-( I've editing to "includes all and only descendants of one ancestor that was also a member". "All" includes extinct and extant, members of sub-clades (other the main one is paraphyletic), and members of traditional phyla if they have the right set of synapomorphies. "Only" excludes members of traditional phyla which don't have the right set of synapomorphies - e.g. traditional flatworms include Acoelomorpha, which are now regarded as basal bilaterians, and flatworms are a clade if Acoelomorpha are excluded. --Philcha (talk) 09:34, 20 February 2011 (UTC)
  • Thollesson, Mikael; Jon L. Norenburg (February 2003) (cited) say, "There is no doubt that the phylum Nemertea is monophyletic", and I've found no contrary opinions. --Philcha (talk) 15:18, 21 February 2011 (UTC)
    • That way of handling the concept of monophyly works for me. Regarding "there is no doubt", this isn't a deal-breaker, but I basically feel that opinions of that sort can reasonably be stated by writers in their own voice but ought not to be stated so definitely in the Voice of Wikipedia -- but I won't badger you on that point. Looie496 (talk) 19:33, 21 February 2011 (UTC)
      • Now "Thollesson and Norenburg (2003) have no doubt that ... monophyletic". --Philcha (talk) 22:02, 21 February 2011 (UTC)

• Could the article explain that synapomorphies are features that are common to a clade but differentiate it from other clades?
  • "distinctive features"? --Philcha (talk) 09:34, 20 February 2011 (UTC)
  • Synapomorphies is short but good. Ruppert, Fox and Barnes (2004) p. 2-3 say "a uniquely shared character" and also explains that it must be shared by the whole family tree including the shared ancestor but no further back in the lineage. I suggest "synapomorphy (a trait shared by an ancestor and all its descendants, but not by other groups)". --Philcha (talk) 15:18, 21 February 2011 (UTC)
    • That would work for me. Looie496 (talk) 19:33, 21 February 2011 (UTC)
      • Done. --Philcha (talk) 09:39, 22 February 2011 (UTC)

Second paragraph of lede

I've taken a shot at rewriting the second paragraph, which I felt as written was asking too much effort from the reader. Because this would be a major change, I don't want to alter the article before discussing it, though. In this version I've (a) split it up, (b) removed some material that can be left for the body, (c) tried to minimize vocabulary, and (d) tried to explain the unique predation mechanism in a more understandable way. Here is my suggestion:

Most nemerteans use their external cilia to glide on surfaces on a trail of slime. Larger species use muscular waves to crawl, and some swim by dorso-ventral undulations. Some species burrow by means of muscular peristalsis. All nemerteans move slowly.

The majority of nemertians are predatory, and capture their prey using a unique mechanism that involves an extensible proboscis tipped with one or more hard hollow barbs called stylets. Normally the proboscis lies retracted inside a tubular cavity called the rhynchocoel, which lies above the midline, running from the front of the body to the back, ending a little short of the rear of the body. When the animal detects prey in front of it, the proboscis rapidly everts from the rhynchocoel, shooting out like a dart and impaling the prey on the stylet. A very stretchy muscle, which connects the proboscis to the back of the rynchocoel, then contracts to pull in the prey. Not all nemertians are active predators, though: a few species with stubby bodies have instead suckers at the front and back ends, with which they attach to a host, and these species filter feed.

The nemertian central nervous system consists of a brain and a set of ventral nerve cords that connect to the brain and run along the length of the body. The brain is a ring of four clusters of nerve cells positioned around the rhynchocoel near its front end. This arrangement distinguishes nemerteans from most other protostome invertebrates, in which the brain forms a ring that encircles the foregut. On their heads some species of nemerteans have a number of pigment-cup ocelli, which can detect light but not form an image. Most have a variety of chemoreceptors.

This is really just intended as a basis for discussion -- I don't expect it to be acceptable as is. Looie496 (talk) 20:18, 21 February 2011 (UTC)

I've rewritten the lede in my sandbox. What do you think? --Philcha (talk) 12:47, 22 February 2011 (UTC)

That's definitely an improvement, but it still has issues. I would like to suggest an exercise for you to try. For each paragraph in that version, write a topic sentence -- a sentence that can go at the beginning of the paragraph and expresses its theme, such that every sentence in the paragraph bears upon or illustrates that theme. I think you will find it almost impossible to do for most of them; and that's a sign that most of the paragraphs lack unity. But maybe it's just that I am failing to perceive the unity -- if so, then the topic sentences ought to make it clear to me. Looie496 (talk) 17:26, 22 February 2011 (UTC)

"I would like to suggest an exercise for you to try" - hmm. I also has doubts about "a sentence that can go at the beginning of the paragraph and expresses its theme, such that every sentence in the paragraph bears upon or illustrates that theme": it's another sentence, which is a disadvantage in the lede; and sometimes prerequisites must be dealt with before the "payload". --Philcha (talk) 20:49, 22 February 2011 (UTC)

I think the first para is OK. IMO the names are essential, as are the size. --Philcha (talk) 20:49, 22 February 2011 (UTC)

At the level of the 2nd para, we should summarise only the vanilla proboscis, as stylets and "spaghetti" probosces apply to sub-groups. "The foregut, stomach and intestine run a little below the midline of the body and the anus is at the tip of the tail" helps to define the architecture; I don't know where else to put it; but it's importance (especially the anus, whose formation is a synapomorphy of protostomes). And my last attempt is only 5 sentences.

"The brain is a ring of four ganglia, ... - while the brains of most protostome invertebrates encircle the foregut" is concise and contrasts with the brain's position in other protostomes. --Philcha (talk) 20:49, 22 February 2011 (UTC)

Would you want "Nemerteans respire through the skin ... through a network of pipes to the outside" to be a separate para? Not that I mind tweaking MOS' tail. --Philcha (talk) 20:49, 22 February 2011 (UTC)

"All nemerteans move slowly, using their external cilia ..." may be better - in fact I've edited it. There's no "theme" sentence, but "Ecology" sections often include multilpe themes. And in this case I think it progresses from locomotion to habit to how they make a living to enemies. --Philcha (talk) 20:49, 22 February 2011 (UTC)

The "fossils, taxonomy and phylogeny" para also progresses, and I don't see value in a preliminary sentence e.g. "There are uncertainties about the fossil record, taxonomy and phylogeny". --Philcha (talk) 20:49, 22 February 2011 (UTC)

Perhaps we should look at the main text for a time. --Philcha (talk) 20:49, 22 February 2011 (UTC)

PS if you edit the main text, do it in the article, as I've changed it since I coped in from my sandbox. Philcha (talk) 20:55, 22 February 2011 (UTC)

I've put in the lede from my Sandbox ("Lead 1"). --Philcha (talk) 08:19, 4 March 2011 (UTC)

What's the status of this review? No comments in a couple weeks. Wizardman _{Operation Big Bear} 16:24, 15 March 2011 (UTC)

I have found myself sort of paralyzed. On one hand, I have so much respect for Philcha's contributions that I hate to treat this review negatively, and the article certainly contains a lot of important information. On the other hand, the prose of the article is really seriously lacking in organization and readability, but Philcha has not been able to perceive that (as often happens to writers -- the hardest part of writing is being able to see your own prose through the eyes of a reader) and isn't willing to take my word for it. Looie496 (talk) 17:25, 15 March 2011 (UTC)

I'm disappointed that there have been no comments about the main text. --Philcha (talk) 18:45, 15 March 2011 (UTC)

On 4 March 2011 I put in a slimmed down lead. The real difficulty is that nemertea are weird, but no source I've seen says that explicitly: the rhynchocoel and poisoned proboscis are unique; the brain encircles the rhynchocoel, while the brains of other protosomes (if any) encircle the gut; there's no body cavity for other organs; there's no heart or analogue (not even the muscular anterior cross-wise vessels of annelids), and a haphazard circulation that sometimes reverses in some species; the catastrophic metamorphosis of the pilidium larva; some are long but very slim; etc. While I've tried to make the lead as concise as I can, nemertea are unusual in so many ways compared with better-known protosomes such as annelids of molluscs. --Philcha (talk) 18:45, 15 March 2011 (UTC)

I've just done a few minor copyedits. --Philcha (talk) 18:45, 15 March 2011 (UTC)

It's not fundamentally an issue of conciseness at this point, it's an issue of paragraph structure: the paragraphs have no structure. This makes them unreadable, but it is hard for the person who wrote them to tell that, because the crucial context information is already present in your mind. There are basically two ways to write good paragraphs: first, to be able to see them through the eyes of the reader -- but that's hard-won skill, and even the most experienced writers occasionally fail at it. Second, to follow a method. The most straightforward method is to use an explicit topic sentence and make sure that every sentence in the paragraph functions to explain or illustrate the topic sentence. There are other methods but they are more difficult to use. In any case, I just don't want to move on to the rest of the article, where we will undoubtedly face the same issue again, without getting somewhere here. Looie496 (talk) 19:09, 15 March 2011 (UTC)

First, I'll be on holiday Fri 18 to Mon 28 inclusive. --Philcha (talk) 19:58, 15 March 2011 (UTC)

I can see a small improvement in the lead, partly based on Looie496's "The majority of nemertians are predatory, and capture ..." (but other parts of Looie496's para are not quite right). --Philcha (talk) 19:58, 15 March 2011 (UTC)

The hardest part of a lead is choosing what part of the main text to include or exclude. Hence it would best to review the main text and then return to the lead. When writing articles and when reviewing other's articles, I do the lead last, to get the main content in my head first. If you review the main text of this article, you may find items that should have more or less emphasis in the lead, or should be reorganised. --Philcha (talk) 19:58, 15 March 2011 (UTC)

Resuming

Okay, I'm back. I have gone over the body of the article per your suggestion. Unfortunately, I am hitting the same problem here as in the lead: lack of paragraph structure. With a few exceptions, most of the paragraphs consist of sentences having little relationship to the ones before and after them, with paragraph breaks inserted at arbitrary points. I almost despair of getting anywhere with this, because I don't think you believe me about the extent of the problem, but I would like to take one more shot, and if it doesn't go anywhere I'm afraid I will have to give up. I would like for you to read this page, especially the part about troubleshooting paragraphs. Once you have, I would like for us to pick two or three of your paragraphs and go through the five-step sequence described there. I think there is a good chance that once you grasp the problem and understand how it ought to be done, you will be able to do it. I don't object to putting effort into this, because I think you are a writer with a lot of important things to say -- but if you can't learn to construct a proper paragraph, you will never be able to get readers to follow you. Looie496 (talk) 17:32, 3 April 2011 (UTC)

Hi, Looie496, it's nice to see you back. I'm reading Paragraphs. It's "spiritual songs" example is literary and IMO verbose - e.g. "Spiritual songs were ostensibly religious, but often an allegory for slaves' desire to escape from the Southern United States to the free states of the North" is more concise and a little more informative ("from the Southern United States ..."). For zoology, the "piranhas" example is more relevant but too simple, as most readers will already have a good mental model of fish. For invertebates, especially "minor phyla", you have to build up the whole from the ground up. And nemertea are the most weird I've worked on. --Philcha (talk) 00:21, 4 April 2011 (UTC)

First, what do you think of the order of main sections? Then we can look at the structure within sections. When reading my textbooks, the only way I could get the anatomy into my head was as concentric tubes, then the gut and rhynchoel, then the proboscis. Then we can think about phrasing sentences. --Philcha (talk) 00:21, 4 April 2011 (UTC)

In generally I can't see how to include the kind of introductory and wrap-up sentences that Paragraphs recommends. WP:V forbids introductory and wrap-up sentences that are completely composed by WP editors. Textbooks give much less space to minor phyla (e.g. 10 or few pages, while arthropods can get over 100), despite the fact that minor phyla are as complex (and simpler than sponges or cnidaria, which are "major phyla"). Journal articles are for experts, and journals impose space limits, so introductory and wrap-up sentences are very rare. The "quality popular" magazines very seldom describe minor phyla, and a Google for [http://www.google.co.uk/search?q=nemertea+nemertine+Nemertinea+Rhynchocoela+%22Scientific+American%22+%22National+Geographic%22+%22New+Science%22&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a nemertea nemertine Nemertinea Rhynchocoela "Scientific American" "National Geographic" "New Science" got me just 1 hit, and that one was no use. I can write introductory and wrap-up sentences (e.g. at top of this para), but the constraints of WP:V and publisher's practice make them practically impossible.</wrap-up> --Philcha (talk) 00:21, 4 April 2011 (UTC)

Example

Let me work through one paragraph as an example. I'll take the first paragraph of the Description section, dropping the refs but numbering the sentences for convenience:

• (1) The typical nemertean body is very slim in proportion to its length. (2) The smallest are a few millimeters long, most are less than 20 centimetres (7.9 in), several exceed 1 metre (3.3 ft), and the longest animal ever found, at 54 metres (177 ft) long, may a specimen of Lineus longissimus, although L. longissimus is usually only a few millimeters wide. (3) The bodies of most nemerteans can stretch a lot, up to 10 times their resting length in some species, but reduce their length to 50% and increase their width to 300% when disturbed. (4) A few have relatively short but wide bodies, for example Malacobdella grossa is up to 3.5 centimetres (1.4 in) long and 1 centimetre (0.39 in) wide, and some of these are much less stretchy. (5) Smaller nemerteans are approximately cylindrical, but larger species are flattened dorso-ventrally (between back and belly). (6) Many have visible patterns in various combinations of yellow, orange, red and green.

First and most basic question: what is the topic of this paragraph? The first sentence will lead a reader to think that the topic is the slimness of the body, but the rest of the paragraph indicates that the topic is really shape in a broader sense. It seems to me that the take-home of the paragraph is that nemertian bodies are cylinders or flattened cylinders, and a few are short and wide but most are long and slender. If that is the topic then sentence 2 only supports it partially, because it gives a lot of info about length but only mentions width for L. longissimus. Sentence 3 relates to the topic because stretching involves a change in shape: the sentence should make that connection explicit. Sentence 6 is completely off topic, and does not belong in this paragraph.

Here is a rewrite that attempts to address those issues:

• Nemertian bodies are shaped like cylinders or flattened cylinders; a few are short and wide but most are long and slim. Smaller nemerteans are nearly round in cross-section, but larger species are flattened dorso-ventrally (between back and belly). The majority are very slender in proportion to their length, but there are a few exceptions such as Malacobdella grossa, which is typically around 3.5 centimetres long and 1 centimetre wide. The smallest are a few millimeters long, and most are less than 20 centimetres in length, but several exceed 1 metre. The longest animal ever found, at 54 metres, was a nemertian classified as Lineus longissimus (although L. longissimus is usually only a few millimeters wide). These shapes are actually changeable, though: the bodies of most nemerteans can stretch, up to 10 times their resting length in some species, or contract, with some species capable of reducing their length by 50% and increasing their width by a factor of three when disturbed.

This rewrite was based on three principles: (1) identify the topic of the paragraph; (2) make sure the beginning of the paragraph tells the reader what its topic is; (3) make sure every sentence has a clear relationship to the topic. I don't claim that it is perfect. The third sentence is still problematic because it talks about length rather than shape. For the sentence about L. longissimus, I had to change the meaning in order to show the relationship to the topic; not sure it is correct as written. The sentence also leaves it ambiguous how wide the 54m specimen was -- I can't say because I don't know. Beyond all that, I'm not completely sure that the controlling idea I used to organize the paragraph is the same controlling idea you had in mind when you wrote the paragraph.

Is this making any sense? I can do the same thing for a couple more. This was actually one of your better paragraphs -- the two that follow it are much worse. They don't seem to have any sort of controlling idea that I can identify, even implicitly. Looie496 (talk) 01:43, 4 April 2011 (UTC)

Hi, Looie496. Thanks, I think your example "Nemertian bodies are shaped like cylinders or flattened cylinders; a few are short and wide but most are long and slim. Smaller nemerteans are nearly round in cross-section, ..." shows how we differ. For me, the very long but very slim body is the main point, with numbers and citations, as IMO no other phylum has such proportions - except that bdellonemerteans are stubby and small. For me "cylinders or flattened cylinders" belongs in the same para (body shape) but is less striking, as this is common in animals that respire by diffusion, e.g. flatworms. The bit about colours needs to go somewhere, and I like it here as an antidote to the drab lead pic. Perhaps I should re-title the section "Appearance and body structure".

While thinking about this, I've realised that I use (sub-)headings as introductory "sentences". In WP they're very useful, as they are the base of the TOC and serve as internal links. And for me, paragraph breaks signal a change.

In the 2nd para, IMO "The outermost layer of the body ..." is a strong hint that concentric layers are coming, but I want to use "concentric tubes" for the mesenchyme.

The para "The mouth is ventral and a little behind the front of the body. ..." has 2 functions: the digestive system is a "conventional" straight-through tube (unlike flatworms, which have no, 1 or a few anuses); and it completes the setting for the proboscis. --Philcha (talk) 09:35, 4 April 2011 (UTC)

Well, you see, the real essential point here is that I was unable to discern your main point. You are saying that the first sentence really did communicate the main point -- but half of the material in the paragraph was unrelated to that point. I think your use of the term "introductory sentence" is a sign of what is going wrong here. A topic sentence is not an introductory sentence, it is an explicit statement of the controlling idea of the paragraph. It does not imply redundancy: the controlling idea must be made clear, but it need not be repeated. And subheadings are not a substitute: they aren't fully expressed ideas, and you can't have one for every paragraph.

It isn't that you are incapable of doing this. When I look over our discussions on this page, I see that virtually every paragraph you have written begins with a proper topic sentence and shows proper logical structure, with everything in the paragraph serving to support its main point. And in earlier articles of yours that I have reviewed I don't recall seeing the problem to nearly such a degree. As far as I can tell it is just something that has showed up in this article.

Regarding "The mouth is ventral...": a paragraph should only have one function or it will confuse readers. The point about the digestive system being a straight-through tube seems like a fine controlling idea: you can say this in your topic sentence and then make sure that everything else in the paragraph serves to support it, by illustrating it, explaining it, adding detail, or giving evidence for it.

Let me also address the point about colours. You can't stick a sentence into a paragraph where it does not belong. When readers go through a paragraph, they automatically make a guess about its controlling idea and then automatically try to relate everything they read to that controlling idea. If they are unable to do so, they are baffled and frustrated. If you feel a need to put something into a paragraph that does not fit its controlling idea, it is a sign that either the controlling idea was not well-chosen, or the top-level structure of the presentation is inadequate. In any case, it is better to write a one-sentence paragraph than to place a sentence in a paragraph whose controlling idea is unrelated to it. Looie496 (talk) 17:00, 4 April 2011 (UTC)

Philcha asking for a 2nd opinion

Hi, Looie496. I'm asking at WT:GAN for a 2nd opinion as we seem to have very different priorities. I'm summarising concisely here why I prefer the general style of the article, and I hope you will summarise your view. My summary is mainly about section "Body structure and major cavities", which is a foundation for "Proboscis and feeding" and the other sections: --Philcha (talk) 13:40, 5 April 2011 (UTC)

• Nemerteans are very odd animals, at all levels of their anatomy and physiology - if a source said "weird", I'd use it. For the general reader, I think the simplest way is to describe the most visible features, and then the main internal features (the concentric tubes and the mesenchyme), and then main organs / subsystems (especially proboscis). --Philcha (talk) 13:37, 5 April 2011 (UTC)
• I sympathise with Looie496's desire for controlling ideas, but: IMO WP:V forbids editors from adding their own topic sentences; and sources don't provide them, as all are reluctant to use much space on "minor phyla". --Philcha (talk) 13:37, 5 April 2011 (UTC)
• Looie496's "topic sentences" imply shorter paragraphs. Up to a point I sympathise, see User:Philcha#My_thoughts_on_style and especially Kathy Henning's Writing for Readers Who Scan, which advises "Include one idea per paragraph". But there's a trade-off: with more, smaller paras, it's hard to see what are lowest-level paras and which paras apply to series of lowest-level paras (e.g. A, A1, A2, ..., B, B1, ...). --Philcha (talk) 13:37, 5 April 2011 (UTC)

Here is a summary of my view: the article contains most of the information that it should, but it is rendered virtually unreadable by lack of structure, especially at the paragraph level. Many of the paragraphs have the appearance of randomly-strung-together sequences of sentences. I don't think I need to say more: if there are 2nd opinions that disagree with me, I'm prepared to withdraw from this article and let somebody else review it. (I have, however, said a lot more about the problem in earlier parts of this page.) Looie496 (talk) 22:02, 5 April 2011 (UTC)

Aircorns 2c

The first things that I noticed about the article were that the lead is far too long and the annotated image floats in the middle of my screen leaving a large amount of white space to its right. As to the prose I must agree with Looie. For example the sentence The smallest are a few millimeters long, most are less than 20 centimetres (7.9 in), several exceed 1 metre (3.3 ft), and the longest animal ever found, at 54 metres (177 ft) long, may a specimen of Lineus longissimus, although L. longissimus is usually only a few millimeters wide is too long, contains far to much information and doesn't really tell me anything apart from the fact that the size varies a lot. Its a shame because it contains a lot of great information, but it needs to be made much more concise in my opinion. Note that I have only quickly skimmed the dialog above and may have missed some of these points being dealt with. AIRcorn (talk) 09:48, 18 April 2011 (UTC)

Thanks for giving a 2nd opinion, Aircorn. I hope you will comment on other parts of the article. --Philcha (talk) 14:07, 18 April 2011 (UTC)

Re your comments so far:

• The leads of GAs about invertebrate phyla as long - see User:Philcha#Improved_and_got_passed_as_GA ("zoology"). A phylum is a topic with many aspects, each of which should be included per WP:LEAD, "The lead should be able to stand alone as a concise overview of the article ...". Each invertebrate phylum is quite different, and general readers have no background information about invertebrate phyla they way they have with vertebrates. Nemertea are the weirdest I've seen, and if a source said that, I'd quote it as the lead sentence. Examples of weirdness: proportions, rhynchocoel, proboscis, location of brain, haphazard circulation, sewer system serving protonephridia. At Talk:Flatworm/GA3, Looie496 and I joked about the length of the lead, and then at one point suggested ("Sigh. Having pushed you to shorten the lead, ...") another point be added but we could not fit it in. --Philcha (talk) 16:14, 18 April 2011 (UTC)
• I could clip "The smallest are a few millimeters long, most are less than 20 centimetres (7.9 in), several exceed 1 metre (3.3 ft), and the longest animal ever found, at 54 metres (177 ft) long, may a specimen of Lineus longissimus, although L. longissimus is usually only a few millimeters wide", but the smallest, typical and longest lengths are needed, as is the slimness. --Philcha (talk) 16:14, 18 April 2011 (UTC)
• It might be best to review the main text first, and then the lead, to see that the lead contains a summary and only a summary of the main text. --Philcha (talk) 16:14, 18 April 2011 (UTC)
• I've clipped the first diagram. --Philcha (talk) 15:54, 18 April 2011 (UTC)

I have a quite a bit on my plate with other reviews at the moment and am afraid I won't be able to do this justice. I also do not wish to take over from Looie and only offered my opinion as I saw this had been mentioned at Wikipedia talk:Good article nominations for a while and no one had taken it up yet. I will respond to a few things however. WP:LEAD suggests three to four paragraphs for the lead (Flatworm has five while this currently sits at six and also has a thousand extra characters). There may be a way to tighten up the description without losing too much. As for the quoted sentence, I was thinking of something like "Most Nemertea vary in size from a few millimeters to 1 metre. However, one has been measured at 54 metres, which would make it the longest animal ever discovered." That is just a rough idea and could easily be expanded on or changed, but I feel the longest measured should have its own sentence. This was also just an example of one of the more difficult sentences, there are other sentences and even paragraphs that need work too. I moved the diagram down a paragraph and that fixed the whitespace issue for me. Feel free to change it around if it doesn't work for you. Good luck. AIRcorn (talk) 03:09, 19 April 2011 (UTC)

• Re the lead, there's a 3-way conflict of principles: WP:LEAD suggests three to four paragraphs for the lead; WP:LEAD says "The lead should be able to stand alone as a concise overview of the article ..."; and writers on web usability says 1 para should contain 1 idea (Writing for Readers Who Scan, Editorial Style). MOS is based on academic style guides, especially The Chicago Manual of Style, which are written for academics and primarily published in hard-copy. Most WP readers are teenagers or adults who have the reading capabilities of teenagers. And most WP users read from screens, which have a much lower dot pitch than printers, in other words screens are more "grainy" and readers become tired more quickly. So IMO any fixed limitation on the number of paras is inappropriate. My GAs on non-scientific topics generally have 3 - 4 paras,and Dragon's Egg has only 2. --Philcha (talk) 08:10, 19 April 2011 (UTC)
• I found An introduction to the invertebrates pp. 75-86 uses "very unusual" and "distinctive body plan" (general) and "unique" (of formation of the circulatory system). But I'm reluctant to add more words, especially if attribution is required, as it means nothing to general readers. --Philcha (talk) 16:35, 19 April 2011 (UTC)

Other articles covering broad topics seem to be able to cover them adequately in only a few paragraphs. Information can be simplified and grouped together where possible, for example they can be found in the open ocean, within freshwater or on the land in cool, damp places. The detail (numbers and exact places) can be left for the body. This will also make it easier for the teenagers. Other parts can be left out, although what is really an editorial decision that I am not confident to make. Maybe many have patterns of yellow, orange, red and green coloration is not that important for the lead, although it is good to have a description of their colour. I would keep your first and sixth paragraphs focussed as they are (history/basic description and Taxonomy/Evolutionary history) and try and shorten the rest into ideally two paragraphs. Maybe add some more basic descriptions to the first paragraph, and spend the rest describing the "weirdness" and ecological impact. Just some ideas. AIRcorn (talk) 10:29, 22 April 2011 (UTC)

Comments by EdJohnston

I don't know how GA reviews work, but I may leave a couple of comments. I found it hard to figure out what these worms look like from the opening image. My suggestion would be to grab some 19th century diagrams from the Leuckart wall charts. The one with Nemertinea is here: http://www.mblwhoilibrary.org/exhibits/leuckart/wall_charts/images/L35.GIF. Although MBL has put a 1995 copyright notice on it, it is simply their scan of the chart published by Rudolf Leuckart in the 19th century, so it is likely to be OK for our use. It would help to know what the key numbers and letters mean. I suppose that image wouldn't be suitable unless it were cleaned up. EdJohnston (talk) 16:07, 9 April 2011 (UTC)

Hi, EdJohnston. If your "opening image" means what WP calls the lead article - in the top right of the page - a multi-part set of diagrams like Leuckart's have 2 problems in that position: they'd be small to discern; and any explanation would be a long away, after the lead (summary) and Table of Contents. --Philcha (talk) 20:17, 9 April 2011 (UTC)

I see your point. How about swapping that image with the one of Basiodiscus mexicanus, currently lower down on the page? I guess the shock is that the gray-tube image looks like a limp white hose, possibly a dead animal. Regarding the Leuckart drawing, I had imagined that someone could cut out a suitable figure from the Leuckart image to make it bigger. Its appeal is that it looks artistic. Probably the background would have to be removed. EdJohnston (talk) 23:30, 9 April 2011 (UTC)

The Leuckart drawing has very poor quality, and I don't have the time or tools to improve it. IMO the 2 anatomical drawings do a good job (I made them for their purposes). The lead may be of a resting animal - they have low BMR (see section "Respiration"), and a good meal could be enough for a long time. There are very few pics of nemerteans at FIST (I've just checked again), and the article uses most of the good ones - most of the others show preserved nemerteans in jars. There are others on Google Images, but WP:IMAGES is very strict about copyright and checking and getting permission is time-consuming. --Philcha (talk) 07:36, 10 April 2011 (UTC)

Comments by Lambanog

Took a quick glance at the lede only. I'd say there are problems with it. The lede is too long. Rule of thumb would be four paragraphs max. Maybe you are describing too much the members of the phylum and not the phylum itself? For example an article on Asia need not go into detail about all the characteristics of each country in Asia.

The technical detail seems to be there but the language seems spotty. First sentence: "Nemertea is a phylum of invertebrate animals also known as ribbon worms or proboscis worms." The phylum is known as ribbon worms or probiscus worms? All invertebrate animals are ribbon worms or probiscus worms? Sentence should be rephrased. I fear there are other instances that impede the flow of reading. I congratulate Philcha for the impressive work put into researching the article, but the language needs work. The good news is researching the technical details is the hard part; improving the language should be easier.

I do not understand the issue with topic sentences. One should be able to rephrase and reorganize data without distorting their meaning. That shouldn't necessarily be considered editorializing unless one is introducing new information. Lambanog (talk) 18:21, 11 May 2011 (UTC)