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I'm a casual reader of many of the science articles here on Wiki. This topic is very interesting, but the article is impenetrable to me. I thought to check the talk page for enlightenment, and find an absolutely gargantuan amount of nearly religious dissection of all of this. I can't believe that it can't be described well, even as a base abstract concept. A few illustrations would be VERY helpful, especially a side-by-side description of the same group, expressed as a clade, and taxanomically (which, I realize, may not be an actual word). If this is the current, or perhaps a current methodology, then there must be some intro textbook which makes this understandable. - superβεεcat 04:03, 28 June 2009 (UTC)
I don't get it either. -- 68.118.201.68 ( talk) 21:31, 12 January 2013 (UTC)
The concepts of a clade, monophyletic, etc. are not the difficulty. I don't think they are hard to understand. The problem is the writing, which is confusing. Moreover the same editor worked on all these articles so they are all confusing. I don't want to pick on individuals. Let me say this. The goal is to impress not to clarify. I would therefore conclude the main author is on the junior side. That isn't his fault, is it? He wants to impress us but we want to be led by the hand. I can say what the article needs, too, a word-by-word careful editing with some rewriting. I can say why you aren't doing it also, because it is a lot of work. Well look, no pain no gain. Let's get the basic writing clear then we can worry about the nuances. I'm starting with cladistics. I plan to edit these several articles for basic writing and formatting. If you have a flare for writing I invite you to join me. We don't need more bad writing. You can always check what is said. I'm not rewriting the whole thing only making clear what is not clear. Then you can see to decide what goes in there. So, you will see small changes slowly happening here and there. I work slow. Ciao. Dave ( talk) 05:34, 17 January 2010 (UTC)
Cladistics is no doubt parsimonious and so is prose, especially encyclopedic. However, there is only so much you can do with parsimony. You can't apeak without speaking. You cannot explain the whole history of the world in a single introductory paragraph. When Hawking proposed to represent the unified grand field with a single variable, phi, members of the astonished audience exclaimed, phi? That's it, phi? So, I find the introduction to this article somewhat too parsimonious. I plan to expand it a little. Correct me if I'm wrong, but you (or I) need SOME space to explain things in a meaningful and connected manner. Dave ( talk) 11:33, 20 January 2010 (UTC)
This section is written from a moral point of view and the editor sprinkles it amply with prejudcial pronouncements. We are to see taxonomy as the dead hand of the past weighing on the minds of the living like an alp. The taxonomists because of their moral turpitude developed this rigid scheme to keep the young free thinkers of today in bondage but they like anyopne under 30 anywhere have developed their own savior study of cladistics with which they are going to save biology with the one and true way. One almost wants to throw the pope in there somewhere just for good measure. We have had to listen to this malarky for something over several hundred years through Martin Luther, Karl Marx the puritans and a host of other saviors now long forgotten. Excuse me, but I just can't resist. Cladistics is not a savior. It is not going to replace taxonomy. It is just a passing fad, and it is not in the slightest degree any less rigid than Linnaean taxonomy or any more progressive or anything else more. The reptiles include birds? Give me a break! We aren't going to see an end to paraphyly in my day or any of yours either. Cladistics contains a relatively objective assessment of the merits and shortcomings of each system, although one commentator remarks that it is not as objective as he would like. Compared to this it is the soul of blandness.
What we have here are two different systems with two different intents. Neither system by itself is adequate to scientifically portray life on Earth as we see it now. We want information that is presented by both systems and the classification of living things is making such adjustments to either as seems best for the data available at the time. We aren't interested in having the personification of cladistics contront the father figure of taxonomy in an adolescent or post-adolescent manner; many of us are beyond that now, me by quite a bit. I'm going through there and will try to add some equilibrium of language and viewpoint. If I fail back me up. Dave ( talk) 16:47, 21 January 2010 (UTC)
Well, I'm glad you addressed that confusing problem. Exactly what is an "organism?" I'm not sure I agree with you entirely. I've never seen any cladograms representing descents of individuals. My feeling is, since the term originated with concern for species, it should stay specific, as, in a sexual system, reproduction except for parthenogenesis and cloning never involves individuals, always pairs. But, as you have addressed these issues and it seems clear that some writers want to include individuals I cannot make up my mind. So, I'm not going to alter it further. If anyone wants to take a hand go ahead, as long as you produce an improvement. For the general public, you canot assume specialist knowledge or knowledge of specialist conventions and vocabulary, you have to give us cues that seem obvious to the trained biologist. Dave ( talk) 13:03, 22 January 2010 (UTC)
I've always read that Mammals came from Reptiles and there are numerous examples of fossil intermediaries betwee them. In our diagram they do not come from reptiles they come from amniotes. The caption implies that they come from reptiles. This is very confusing. Anyone got any suggestions? Unless we change the diagram or the write-up we are going to lose the reader on that one. PS I got to go now, I'll be on this for a day or two. There are some other problems. Dave ( talk) 14:40, 22 January 2010 (UTC)
Further problem with the diagram: The colored areas in the cladogram do not extend far enough down. They should encompass nodes (points where lines turn through 90 degrees) rather than ending on vertical lines. This is because the organisms are represented by nodes, not by lines. (Lines show lineage connections). I think this correction may help those who find the diagram hard to understand. — Preceding unsigned comment added by NitramFortune ( talk • contribs) 14:18, 15 August 2016 (UTC) [Apologies: I should have signed my previous suggestion. I'm new to Wiki editing] NitramFortune ( talk) 11:47, 16 August 2016 (UTC)
Thanks for pointing out the distinction. However, in the legend for the top diagram on the page it says: "showing the last common ancestor of the composite tree, which is the vertical line 'trunk' (stem) at the bottom, with all descendant branches shown above." By my reading this confuses the two issues you mention. The primate tree further down the page clearly shows lineages because the lines are all at the same angle and divide into branches: No individual species are implied and I'm happy that it represents the continuum of populations. The top diagram, because it has both horizontal and vertical lines, and therefore nodes, is really a cladistic tree, hence my earlier suggestion for changing the extent of the colored areas. NitramFortune ( talk) 08:41, 17 August 2016 (UTC)
I'm back. Other people might think this worrying about the fine points is a waste of time, but it isn't. The fine points make the difference between good work and just work. I'm willing to say we got past the diagram. But now, there is this obscure sentence:
"Contrary to the Linnaean systems where taxons are defined by describing key traits (apomorphies), cladisc taxons (clades) are named."
My understanding is that apomorphy is a cladistic term. But you said, "the Linnaean systems, where .... There are two different systems. A taxon is only defined by its apomorphy if that taxon is a clade within a clade. But, we're not talking clades, we're talking Linnaean. This is confusing, but it gets worse. You mean, taxons are not named? What is the taxon name? I suppose you mean that a taxon is defined by its key traits, but a clade is defined by its position in a line of descent. It leaves too much to be guessed, such as what you mean by definition, what you mean by naming. Also English does not have a word Cladisc. The equivalent would be cladish and that would be understood but it would be a neologism, people don't use it. Cladistic is better, but there are the other issues. Tomorrow. Dave ( talk) 03:33, 23 January 2010 (UTC)
Outstanding response. We are making progress here. Time for the next item:
"In node-based naming, taxon name A refers to the least inclusive clade containing X and Y."
This is a writing criticism. This is too parsimonious to make sense without a lot of thought and then not for general readers. What on earth is X and Y? You haven't said and unless we already knew we would never guess. The reader goes to us for definition and we start spouting letters at him. Well, PQR, and furthermore, YUV, and what is more JLZ. Ho ho. Second, can you detail what you mean by inclusive and exclusive? One always has to keep the audience in mind. I would say the sentence is aimed at the student in the field, but that is what the audience for the most part is NOT. Professionals don't need us, the public does, and they need us to explain it. We're doing good here so far. I was afraid I'd have to abandon it to the wolves and the vultures as carrion. Dave ( talk) 00:44, 24 January 2010 (UTC)
Dave, I noticed you made this comment in editing: English doesn't use "naming" to mean "definition" - I noticed your use of naming before - naming is purely assigning the name. This is very true, and confused the heck out of me in the beginning too. The thing is, in the technical jargon of cladistics, clades are named, not defined, or described. This should be mentioned in the article. Petter Bøckman ( talk) 09:07, 25 January 2010 (UTC)
OK, here's my suggestion:
Petter Bøckman ( talk) 14:35, 26 January 2010 (UTC)
EDIT: I have now moved details of Linnaeus original system to Systema Naturae, leaving Linnaean taxonomy as a suitable reference for modern hierarchical systematics. It will need to be brushed up a bit, but the basis should be there. Petter Bøckman ( talk) 14:59, 27 January 2010 (UTC)
"Differences between a Linnaean/apomorphy-based clades and a node-based ones become obvious when the phylogenetic hypothesis changes. When two species previously considered closely related are found to belong to different groups (e.g. the giant panda and the red panda), one of the species will be taken out of the Linnaean unit (in this case the "pandas" of the bear family) and transfered to a more appropriate unit or given it's own (the Ailuridae). In cladistics, the unit "pandas", the giant panda + the red panda remain, but the clade is now known to contain all bears as well as mustelids, racoons and kind, skunks and seals. [note 1]<ref>[http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=285902 Wesley-Hunt, Gina D., and John J. Flynn (2005). "Phylogeny of the Carnivores". Journal of Systematic Palaeontology no 3: pp 1-28.]</ref>"
Well, I've been pondering this and researching it for a while. Ostensibly this is an example of how the classification changes if the phylogenetic hypothesis does; that is, some original classification was apomorpy-based but the classifiers saw the true light when they had a node-base cladogram. Then we have this very strange note, which denies there ever was such a classification, but this is only an illustrative example. What? Are we making up examples here? With all that expertise we have to invent examples, we can't find any real ones? I have before me from my collection a book by George B. Schaller (the original gorilla man) called The Last Panda. He has a whole appendix on the topic entitled The Panda as Panda. Detailing the history of the classification he points out that it was always troublesome. Some put the two pandas in either the bears or the raccoons and others split them between the two. So, there was no standard classification based on one synapomorphy. Some thought they were related, some not, based on intuition of apomorphies. The later node-based cladograms didn't offer us anything new or anything different, they only confirmed a more distant relationship. Therefore this is bad example; we want something that was apomorphic and is now nodish and is substantially different, if indeed we need such an example at all. Dave ( talk) 03:27, 27 January 2010 (UTC)
Where does it say "a clade is...[ + atribute (noun phrase)]"???
There's something wrong in this article. There's no real definition of clade. Instead, there's only a description of the procedures required to determine the existence of a clade, the abstract nature of the clade, etc. But what is really a clade??? Not even a person who is somewhat familiarized with taxonomy would be able to tell what they're talking about in the article if we only consider writing (composition).-- Quinceps ( talk) 04:04, 29 January 2010 (UTC)
The article was tagged with a "confusing" tag in 2009, well before the current rewrite. It is still confusing? How do we go about determining if it is now an acceptable read? Ask my old Mom to read it? Just remove the tag?
I just removed an example of a clade ( Archosauria i think it was meant to be) from the intro. I did not remove it because it was a bad example, but because it was not worded to in reference to phylogeny and because I feel the intro is not the place for examples. Examples are a good idea though. Should we dump some of the text on history (which is really more about cladistics, not clades per se) and put in some examples in stead?-- Petter Bøckman ( talk) 17:32, 5 May 2010 (UTC)
The C.E. article would be enhanced by addition of the relevant parts of this article. Alas, I'm not knowledgeable enough to do so. Imagine Reason ( talk) 10:32, 22 July 2011 (UTC)
"The green box is not a clade, but rather represents an evolutionary grade, an incomplete group, because the blue clade descends from it, but is excluded."
Isn't the blue clade ascended from it rather than descended? ScienceApe ( talk) 12:42, 4 September 2011 (UTC)
Bottom line: user interface guidelines strongly recommend that visual displays of information never depend solely upon color to identify or distinguish objects. A significant proportion of the reading audience is colorblind.
I began reading the article with a clear idea of a clade, but after studying the first diagram and caption text found myself thoroughly confused. I am red-green colorblind. The three colored boxes are referred to as red, green and blue, and there are no additional markers to help distinguish the boxes such as hatching, text labels or similar. Indeed, as I am only partially colorblind I can see colors, but they are often ambiguous and can switch back and forth spending on surrounding colors. In the case of this diagram the central color (I have been informed) is a kind of Kermit green, but it's close proximity to the blue box on the left makes it shift to the pinkish red, which then causes the orange-red box to the right to shft to a kind of chartreuse green. Consequently, the middle box which was clearly not a clade was RED to my eyes, and the caption asserted that the red box was a clade, and that the GREEN box they claimed was not a clade sure looked like a clade to me, being the box on the far right.
The simplest solution requiring no image editing is to change the caption text to read:
"Cladogram (family tree) of a biological group. The red and blue boxes at right and left represent clades (i.e., complete branches). The green box in the middle is not a clade, but rather represents an evolutionary grade, an incomplete group, because the blue clade at left is descended from it, but is excluded."
Niles.ritter ( talk) 14:30, 30 June 2012 (UTC)
Whew. What a mess this article was. It was chock full of stuff that belongs in other articles, and half of that was flat wrong.
David Marjanović ( talk) 21:57, 22 September 2012 (UTC)
More generally, I don't disagree with David Marjanović's general point that the article was a bit of a mess. But the way to put it right is to keep strictly to the principles of Wikipedia editing: select relevant reliable sources in a balanced way then report what these sources say. This approach will result in clear and frequent inline referencing. Neither the original nor David Marjanović's revisions meet this standard. Instead, it seems to me, too much has been written "out of people's heads", with too few references added afterwards to support what has already been written. Peter coxhead ( talk) 10:30, 25 September 2012 (UTC)
I've noticed that when written in a taxobox, the word "clade" is sometimes italicized. What's the reason for this? -- Myrddin_Wyllt 2/11/13
I can't tell if there is a missing word here, or is 'preferably' lingo for a form of naming, or is the word 'or' not supposed to be there?
I found a source and wrote: Most biologists are switching to the evolutionary way of classifying organisms.[3] Jonathan Tweet ( talk) 14:26, 27 February 2016 (UTC)
You could be forgiven for suspecting that one of the reasons the clade has become a popular tool of thinking is because it offers a backdoor way of talking about "race" and common descent without having to use the loaded R-word. The way clade-based reconstruction of an old (and partly hypothetical) family tree works in practice, it makes it difficult to see two or more quite different families of animals emerging from the same progenitor species or genus, but exiting the stem (that progenitor species) with a long time in between them, and then diverging far away from one another over time. Clade-based taxonomy does build on an idea that the last common ancestor and its descendants must all share some defining characteristics, in a combination/matrix which in turn sets them apart from everybody else, and that the taxonomy and taxa described are inherently "there" in nature. 83.254.154.164 ( talk) 07:02, 1 February 2015 (UTC)
I may have gone overboard, but this topic is tricky, and I added more to the lead. Jonathan Tweet ( talk) 01:54, 12 May 2015 (UTC)
The third bullet point in the section labeled "Terminology" is:
"In the adjacent diagram, the strepsirrhine clade, including the lemurs and lorises, is basal to the hominoids, the apes and humans."
Neither "strepsirrhine" nor "hominid" appears in the adjacent diagram. I don't know whether this is an omission, or something that should be obvious to the informed reader. But it isn't useful to this naive reader as an example of a "basal clade." — Preceding unsigned comment added by 104.129.194.69 ( talk) 18:37, 19 March 2018 (UTC)
The definition of "basal" given here is simply not correct (for example, compare to the definition given on wikipedia's own definition of "basal" [ (phylogenetics)|here]), and it reinforces a very unfortunate common misunderstanding. No living clade can be considered basal to any other living clade, but rather the (now extinct) nodes of a tree are basal to the lineages that descend from them. Corvus occidentalis ( talk) 03:19, 6 November 2021 (UTC)
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A 'basal clade' is a part of the tree ending at a node before two or more terminal taxa.A part of a tree that does not extend out to its terminal taxa is not a clade; a clade is, by definition, a complete (sub)tree, either with hypothetical interior nodes, as in most published cladograms, or with real interior nodes, now almost entirely limited to hand-constructed diagrams (which some prefer to call 'phylograms').
The opening sentence of the
Clade article contains the link [[Common descent|common ancestor]]
, inviting the reader to go to the
Common descent article. This in turn contains the link [[most recent common ancestor|common ancestor]]
, so the reader now calls up the article
Most recent common ancestor, which defines its topic as
"the most recent individual from which all the organisms of the set are descended" (emphasis added). Rather than continuing to follow links, the reader returns to the
Clade article, only to read that the common ancestor "may be an individual, a
population, a
species (
extinct or
extant), and so on right up to a
kingdom and further."
This won't do. If the phrase "common ancestor" has a different meaning in the Clade and Most recent common ancestor articles, allowing a group in one article but not in the other, the wikilinks should not be chained together this way.
It's not stated clearly, but I think that common ancestors in the article Common descent are limited to species, excluding genera etc. If so, that's yet another meaning for "common ancestor".
Peter Brown ( talk) 01:18, 5 February 2020 (UTC)
Is it actually a good idea for this section to not only link but to *directly state in the text* to see the Wikispecies page for Anas platyrhynchos for an example? My gut instincts tell me no. Monster Iestyn ( talk) 14:26, 29 October 2021 (UTC)
I suggest adding a pronunciation at the beginning of the article. 2600:1700:CC30:8980:4A0:2CD2:FE3C:F87F ( talk) 01:38, 31 December 2021 (UTC)
Cite error: There are <ref group=note>
tags on this page, but the references will not show without a {{reflist|group=note}}
template (see the
help page).
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I'm a casual reader of many of the science articles here on Wiki. This topic is very interesting, but the article is impenetrable to me. I thought to check the talk page for enlightenment, and find an absolutely gargantuan amount of nearly religious dissection of all of this. I can't believe that it can't be described well, even as a base abstract concept. A few illustrations would be VERY helpful, especially a side-by-side description of the same group, expressed as a clade, and taxanomically (which, I realize, may not be an actual word). If this is the current, or perhaps a current methodology, then there must be some intro textbook which makes this understandable. - superβεεcat 04:03, 28 June 2009 (UTC)
I don't get it either. -- 68.118.201.68 ( talk) 21:31, 12 January 2013 (UTC)
The concepts of a clade, monophyletic, etc. are not the difficulty. I don't think they are hard to understand. The problem is the writing, which is confusing. Moreover the same editor worked on all these articles so they are all confusing. I don't want to pick on individuals. Let me say this. The goal is to impress not to clarify. I would therefore conclude the main author is on the junior side. That isn't his fault, is it? He wants to impress us but we want to be led by the hand. I can say what the article needs, too, a word-by-word careful editing with some rewriting. I can say why you aren't doing it also, because it is a lot of work. Well look, no pain no gain. Let's get the basic writing clear then we can worry about the nuances. I'm starting with cladistics. I plan to edit these several articles for basic writing and formatting. If you have a flare for writing I invite you to join me. We don't need more bad writing. You can always check what is said. I'm not rewriting the whole thing only making clear what is not clear. Then you can see to decide what goes in there. So, you will see small changes slowly happening here and there. I work slow. Ciao. Dave ( talk) 05:34, 17 January 2010 (UTC)
Cladistics is no doubt parsimonious and so is prose, especially encyclopedic. However, there is only so much you can do with parsimony. You can't apeak without speaking. You cannot explain the whole history of the world in a single introductory paragraph. When Hawking proposed to represent the unified grand field with a single variable, phi, members of the astonished audience exclaimed, phi? That's it, phi? So, I find the introduction to this article somewhat too parsimonious. I plan to expand it a little. Correct me if I'm wrong, but you (or I) need SOME space to explain things in a meaningful and connected manner. Dave ( talk) 11:33, 20 January 2010 (UTC)
This section is written from a moral point of view and the editor sprinkles it amply with prejudcial pronouncements. We are to see taxonomy as the dead hand of the past weighing on the minds of the living like an alp. The taxonomists because of their moral turpitude developed this rigid scheme to keep the young free thinkers of today in bondage but they like anyopne under 30 anywhere have developed their own savior study of cladistics with which they are going to save biology with the one and true way. One almost wants to throw the pope in there somewhere just for good measure. We have had to listen to this malarky for something over several hundred years through Martin Luther, Karl Marx the puritans and a host of other saviors now long forgotten. Excuse me, but I just can't resist. Cladistics is not a savior. It is not going to replace taxonomy. It is just a passing fad, and it is not in the slightest degree any less rigid than Linnaean taxonomy or any more progressive or anything else more. The reptiles include birds? Give me a break! We aren't going to see an end to paraphyly in my day or any of yours either. Cladistics contains a relatively objective assessment of the merits and shortcomings of each system, although one commentator remarks that it is not as objective as he would like. Compared to this it is the soul of blandness.
What we have here are two different systems with two different intents. Neither system by itself is adequate to scientifically portray life on Earth as we see it now. We want information that is presented by both systems and the classification of living things is making such adjustments to either as seems best for the data available at the time. We aren't interested in having the personification of cladistics contront the father figure of taxonomy in an adolescent or post-adolescent manner; many of us are beyond that now, me by quite a bit. I'm going through there and will try to add some equilibrium of language and viewpoint. If I fail back me up. Dave ( talk) 16:47, 21 January 2010 (UTC)
Well, I'm glad you addressed that confusing problem. Exactly what is an "organism?" I'm not sure I agree with you entirely. I've never seen any cladograms representing descents of individuals. My feeling is, since the term originated with concern for species, it should stay specific, as, in a sexual system, reproduction except for parthenogenesis and cloning never involves individuals, always pairs. But, as you have addressed these issues and it seems clear that some writers want to include individuals I cannot make up my mind. So, I'm not going to alter it further. If anyone wants to take a hand go ahead, as long as you produce an improvement. For the general public, you canot assume specialist knowledge or knowledge of specialist conventions and vocabulary, you have to give us cues that seem obvious to the trained biologist. Dave ( talk) 13:03, 22 January 2010 (UTC)
I've always read that Mammals came from Reptiles and there are numerous examples of fossil intermediaries betwee them. In our diagram they do not come from reptiles they come from amniotes. The caption implies that they come from reptiles. This is very confusing. Anyone got any suggestions? Unless we change the diagram or the write-up we are going to lose the reader on that one. PS I got to go now, I'll be on this for a day or two. There are some other problems. Dave ( talk) 14:40, 22 January 2010 (UTC)
Further problem with the diagram: The colored areas in the cladogram do not extend far enough down. They should encompass nodes (points where lines turn through 90 degrees) rather than ending on vertical lines. This is because the organisms are represented by nodes, not by lines. (Lines show lineage connections). I think this correction may help those who find the diagram hard to understand. — Preceding unsigned comment added by NitramFortune ( talk • contribs) 14:18, 15 August 2016 (UTC) [Apologies: I should have signed my previous suggestion. I'm new to Wiki editing] NitramFortune ( talk) 11:47, 16 August 2016 (UTC)
Thanks for pointing out the distinction. However, in the legend for the top diagram on the page it says: "showing the last common ancestor of the composite tree, which is the vertical line 'trunk' (stem) at the bottom, with all descendant branches shown above." By my reading this confuses the two issues you mention. The primate tree further down the page clearly shows lineages because the lines are all at the same angle and divide into branches: No individual species are implied and I'm happy that it represents the continuum of populations. The top diagram, because it has both horizontal and vertical lines, and therefore nodes, is really a cladistic tree, hence my earlier suggestion for changing the extent of the colored areas. NitramFortune ( talk) 08:41, 17 August 2016 (UTC)
I'm back. Other people might think this worrying about the fine points is a waste of time, but it isn't. The fine points make the difference between good work and just work. I'm willing to say we got past the diagram. But now, there is this obscure sentence:
"Contrary to the Linnaean systems where taxons are defined by describing key traits (apomorphies), cladisc taxons (clades) are named."
My understanding is that apomorphy is a cladistic term. But you said, "the Linnaean systems, where .... There are two different systems. A taxon is only defined by its apomorphy if that taxon is a clade within a clade. But, we're not talking clades, we're talking Linnaean. This is confusing, but it gets worse. You mean, taxons are not named? What is the taxon name? I suppose you mean that a taxon is defined by its key traits, but a clade is defined by its position in a line of descent. It leaves too much to be guessed, such as what you mean by definition, what you mean by naming. Also English does not have a word Cladisc. The equivalent would be cladish and that would be understood but it would be a neologism, people don't use it. Cladistic is better, but there are the other issues. Tomorrow. Dave ( talk) 03:33, 23 January 2010 (UTC)
Outstanding response. We are making progress here. Time for the next item:
"In node-based naming, taxon name A refers to the least inclusive clade containing X and Y."
This is a writing criticism. This is too parsimonious to make sense without a lot of thought and then not for general readers. What on earth is X and Y? You haven't said and unless we already knew we would never guess. The reader goes to us for definition and we start spouting letters at him. Well, PQR, and furthermore, YUV, and what is more JLZ. Ho ho. Second, can you detail what you mean by inclusive and exclusive? One always has to keep the audience in mind. I would say the sentence is aimed at the student in the field, but that is what the audience for the most part is NOT. Professionals don't need us, the public does, and they need us to explain it. We're doing good here so far. I was afraid I'd have to abandon it to the wolves and the vultures as carrion. Dave ( talk) 00:44, 24 January 2010 (UTC)
Dave, I noticed you made this comment in editing: English doesn't use "naming" to mean "definition" - I noticed your use of naming before - naming is purely assigning the name. This is very true, and confused the heck out of me in the beginning too. The thing is, in the technical jargon of cladistics, clades are named, not defined, or described. This should be mentioned in the article. Petter Bøckman ( talk) 09:07, 25 January 2010 (UTC)
OK, here's my suggestion:
Petter Bøckman ( talk) 14:35, 26 January 2010 (UTC)
EDIT: I have now moved details of Linnaeus original system to Systema Naturae, leaving Linnaean taxonomy as a suitable reference for modern hierarchical systematics. It will need to be brushed up a bit, but the basis should be there. Petter Bøckman ( talk) 14:59, 27 January 2010 (UTC)
"Differences between a Linnaean/apomorphy-based clades and a node-based ones become obvious when the phylogenetic hypothesis changes. When two species previously considered closely related are found to belong to different groups (e.g. the giant panda and the red panda), one of the species will be taken out of the Linnaean unit (in this case the "pandas" of the bear family) and transfered to a more appropriate unit or given it's own (the Ailuridae). In cladistics, the unit "pandas", the giant panda + the red panda remain, but the clade is now known to contain all bears as well as mustelids, racoons and kind, skunks and seals. [note 1]<ref>[http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=285902 Wesley-Hunt, Gina D., and John J. Flynn (2005). "Phylogeny of the Carnivores". Journal of Systematic Palaeontology no 3: pp 1-28.]</ref>"
Well, I've been pondering this and researching it for a while. Ostensibly this is an example of how the classification changes if the phylogenetic hypothesis does; that is, some original classification was apomorpy-based but the classifiers saw the true light when they had a node-base cladogram. Then we have this very strange note, which denies there ever was such a classification, but this is only an illustrative example. What? Are we making up examples here? With all that expertise we have to invent examples, we can't find any real ones? I have before me from my collection a book by George B. Schaller (the original gorilla man) called The Last Panda. He has a whole appendix on the topic entitled The Panda as Panda. Detailing the history of the classification he points out that it was always troublesome. Some put the two pandas in either the bears or the raccoons and others split them between the two. So, there was no standard classification based on one synapomorphy. Some thought they were related, some not, based on intuition of apomorphies. The later node-based cladograms didn't offer us anything new or anything different, they only confirmed a more distant relationship. Therefore this is bad example; we want something that was apomorphic and is now nodish and is substantially different, if indeed we need such an example at all. Dave ( talk) 03:27, 27 January 2010 (UTC)
Where does it say "a clade is...[ + atribute (noun phrase)]"???
There's something wrong in this article. There's no real definition of clade. Instead, there's only a description of the procedures required to determine the existence of a clade, the abstract nature of the clade, etc. But what is really a clade??? Not even a person who is somewhat familiarized with taxonomy would be able to tell what they're talking about in the article if we only consider writing (composition).-- Quinceps ( talk) 04:04, 29 January 2010 (UTC)
The article was tagged with a "confusing" tag in 2009, well before the current rewrite. It is still confusing? How do we go about determining if it is now an acceptable read? Ask my old Mom to read it? Just remove the tag?
I just removed an example of a clade ( Archosauria i think it was meant to be) from the intro. I did not remove it because it was a bad example, but because it was not worded to in reference to phylogeny and because I feel the intro is not the place for examples. Examples are a good idea though. Should we dump some of the text on history (which is really more about cladistics, not clades per se) and put in some examples in stead?-- Petter Bøckman ( talk) 17:32, 5 May 2010 (UTC)
The C.E. article would be enhanced by addition of the relevant parts of this article. Alas, I'm not knowledgeable enough to do so. Imagine Reason ( talk) 10:32, 22 July 2011 (UTC)
"The green box is not a clade, but rather represents an evolutionary grade, an incomplete group, because the blue clade descends from it, but is excluded."
Isn't the blue clade ascended from it rather than descended? ScienceApe ( talk) 12:42, 4 September 2011 (UTC)
Bottom line: user interface guidelines strongly recommend that visual displays of information never depend solely upon color to identify or distinguish objects. A significant proportion of the reading audience is colorblind.
I began reading the article with a clear idea of a clade, but after studying the first diagram and caption text found myself thoroughly confused. I am red-green colorblind. The three colored boxes are referred to as red, green and blue, and there are no additional markers to help distinguish the boxes such as hatching, text labels or similar. Indeed, as I am only partially colorblind I can see colors, but they are often ambiguous and can switch back and forth spending on surrounding colors. In the case of this diagram the central color (I have been informed) is a kind of Kermit green, but it's close proximity to the blue box on the left makes it shift to the pinkish red, which then causes the orange-red box to the right to shft to a kind of chartreuse green. Consequently, the middle box which was clearly not a clade was RED to my eyes, and the caption asserted that the red box was a clade, and that the GREEN box they claimed was not a clade sure looked like a clade to me, being the box on the far right.
The simplest solution requiring no image editing is to change the caption text to read:
"Cladogram (family tree) of a biological group. The red and blue boxes at right and left represent clades (i.e., complete branches). The green box in the middle is not a clade, but rather represents an evolutionary grade, an incomplete group, because the blue clade at left is descended from it, but is excluded."
Niles.ritter ( talk) 14:30, 30 June 2012 (UTC)
Whew. What a mess this article was. It was chock full of stuff that belongs in other articles, and half of that was flat wrong.
David Marjanović ( talk) 21:57, 22 September 2012 (UTC)
More generally, I don't disagree with David Marjanović's general point that the article was a bit of a mess. But the way to put it right is to keep strictly to the principles of Wikipedia editing: select relevant reliable sources in a balanced way then report what these sources say. This approach will result in clear and frequent inline referencing. Neither the original nor David Marjanović's revisions meet this standard. Instead, it seems to me, too much has been written "out of people's heads", with too few references added afterwards to support what has already been written. Peter coxhead ( talk) 10:30, 25 September 2012 (UTC)
I've noticed that when written in a taxobox, the word "clade" is sometimes italicized. What's the reason for this? -- Myrddin_Wyllt 2/11/13
I can't tell if there is a missing word here, or is 'preferably' lingo for a form of naming, or is the word 'or' not supposed to be there?
I found a source and wrote: Most biologists are switching to the evolutionary way of classifying organisms.[3] Jonathan Tweet ( talk) 14:26, 27 February 2016 (UTC)
You could be forgiven for suspecting that one of the reasons the clade has become a popular tool of thinking is because it offers a backdoor way of talking about "race" and common descent without having to use the loaded R-word. The way clade-based reconstruction of an old (and partly hypothetical) family tree works in practice, it makes it difficult to see two or more quite different families of animals emerging from the same progenitor species or genus, but exiting the stem (that progenitor species) with a long time in between them, and then diverging far away from one another over time. Clade-based taxonomy does build on an idea that the last common ancestor and its descendants must all share some defining characteristics, in a combination/matrix which in turn sets them apart from everybody else, and that the taxonomy and taxa described are inherently "there" in nature. 83.254.154.164 ( talk) 07:02, 1 February 2015 (UTC)
I may have gone overboard, but this topic is tricky, and I added more to the lead. Jonathan Tweet ( talk) 01:54, 12 May 2015 (UTC)
The third bullet point in the section labeled "Terminology" is:
"In the adjacent diagram, the strepsirrhine clade, including the lemurs and lorises, is basal to the hominoids, the apes and humans."
Neither "strepsirrhine" nor "hominid" appears in the adjacent diagram. I don't know whether this is an omission, or something that should be obvious to the informed reader. But it isn't useful to this naive reader as an example of a "basal clade." — Preceding unsigned comment added by 104.129.194.69 ( talk) 18:37, 19 March 2018 (UTC)
The definition of "basal" given here is simply not correct (for example, compare to the definition given on wikipedia's own definition of "basal" [ (phylogenetics)|here]), and it reinforces a very unfortunate common misunderstanding. No living clade can be considered basal to any other living clade, but rather the (now extinct) nodes of a tree are basal to the lineages that descend from them. Corvus occidentalis ( talk) 03:19, 6 November 2021 (UTC)
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A 'basal clade' is a part of the tree ending at a node before two or more terminal taxa.A part of a tree that does not extend out to its terminal taxa is not a clade; a clade is, by definition, a complete (sub)tree, either with hypothetical interior nodes, as in most published cladograms, or with real interior nodes, now almost entirely limited to hand-constructed diagrams (which some prefer to call 'phylograms').
The opening sentence of the
Clade article contains the link [[Common descent|common ancestor]]
, inviting the reader to go to the
Common descent article. This in turn contains the link [[most recent common ancestor|common ancestor]]
, so the reader now calls up the article
Most recent common ancestor, which defines its topic as
"the most recent individual from which all the organisms of the set are descended" (emphasis added). Rather than continuing to follow links, the reader returns to the
Clade article, only to read that the common ancestor "may be an individual, a
population, a
species (
extinct or
extant), and so on right up to a
kingdom and further."
This won't do. If the phrase "common ancestor" has a different meaning in the Clade and Most recent common ancestor articles, allowing a group in one article but not in the other, the wikilinks should not be chained together this way.
It's not stated clearly, but I think that common ancestors in the article Common descent are limited to species, excluding genera etc. If so, that's yet another meaning for "common ancestor".
Peter Brown ( talk) 01:18, 5 February 2020 (UTC)
Is it actually a good idea for this section to not only link but to *directly state in the text* to see the Wikispecies page for Anas platyrhynchos for an example? My gut instincts tell me no. Monster Iestyn ( talk) 14:26, 29 October 2021 (UTC)
I suggest adding a pronunciation at the beginning of the article. 2600:1700:CC30:8980:4A0:2CD2:FE3C:F87F ( talk) 01:38, 31 December 2021 (UTC)
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help page).