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Comment from a non-biologist: Two articles seem to contradict each other; this article's lead paragraph lists birds as a member of the class of Sauropsida, but the article on birds lists Aves as a separate class. The taxonomic details on this page is more recent (Goodrich vs. Linnaeus), but if there is still disagreement on the issue, this should be indicated on both pages, and if the apparent disagreement has been resolved, then the two pages (and pages on individual genera and species) should use the same taxonomy. --Thorsen 05:15, 27 November 2006 (UTC)[reply]


I replaced the old taxonomic hierarchy of microphylum nanophylum etc with the one suggested by Dr Mike Benton of Bristol University, in the newest edition of his textbook Vertebrate Paleontology. Since this is a widely used and respected work, I feel this classification is more appropriate to the Wikipedia than the eccentric one previously adopted.

M Alan Kazlev 01:56, 24 Feb 2005 (UTC)

I replaced the taxobox with the more userfriendly one, which I copied from Synapsida (before I saw this talk). Is Benton's classification applicable there too? Phlebas 19:06, 30 Mar 2005 (UTC)
Yes his book is a standard textbook. While one might quibble with minor points of interepretation (as palaeontologists often do), overall it is an excellent guide. It supplements (and can serve as an intro to) Carroll's Vertebrate Palaeontology and Evolution (1988), an excellent book that however was written before the cladistic approach became standard, hence Carroll in the back of his book follows the Linnean scheme of Class, Order, etc.
So the taxonomic hierarchy of the vertebrates, according to the 2004 edition of Benton's book is a good guideline and can certainly be used as an outline classification (although as i said one might quibble with points of detail)
What i have been doing, since the taxobox used here is the standard one on the wikipedia, is using an "unranked" heading, as in Archosaur, or else division and subdivion. But since our task is to summarise and present and interpret as an Encyclopaedia, not come up with new unreferenced ideas, there is no justification for using the terms "microphylum" or "nanophylum", unless there is a reference to a scientific journal or peer reviewed essay which presents this terminology (I don't know of any; in fact before coming to wikipedia I'd never heard these terms). Of course that infraphylum and superclass are perfectly good terms M Alan Kazlev 00:18, 31 Mar 2005 (UTC)

Sauropsid or Reptile?

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While I agree that Benton's taxonomy is an excellent choise to use across the wikipedia vertebrate pages, I'm starting to think using class Sauropsida instead of the widely used and well-known Reptilia might be a little too arcane for an encyclopedia like this one. It seems like it would be far simpler to preserve Class Reptilia for all traditional reptiles except Synapsids, rahter than try to convert all the entries on living reptile species to Sauropsida and create confusion. This page should defiantely stay up as an explainatory entry, but I think adding a prominent link to Reptile and using Class Reptilia somewhere in the taxobox would be useful, since they are essentially synonyms. Dinoguy2 01:56, 11 December 2005 (UTC)[reply]

There is always a problem when applying Linnaean names and ranks to Cladistic taxa. Reptilia (Linnaean) is paraphyletic and includes non-mammalian Synapsida; Reptilia (Cladistic) is monophyletic and excludes all Synapsida. There is also the question of whether Mesosaurus is a sauropsid but not a reptile, vice versa, or both  :-) (latest research (according to an email from Robert Reisz) indicates it's an Anapsid/Parareptile) I guess the Phylocode will help clear up some of these ambiguities M Alan Kazlev 06:53, 11 December 2005 (UTC)[reply]

Class Sauropsida has been in place on Reptile and other reptile related pages for some time now without complaint. Since "Reptile" is the common name for Class Sauropsida, I move that this page be merged with Reptile. Most of this is taxonomic history that could fit under the classification section there. Having two pages for the same clade just creates confusion when making taxobox links, etc. For example, I always code (Reptile|Sauropsida) to list the proper class but point to the more relevent page, while others just use (Sauropsid)a and point here when more relevent info can be found at Reptile.Dinoguy2 21:51, 30 January 2006 (UTC)[reply]

Neither "Reptilia" nor "Sauropsida" refer to clades on wikipedia though. The paraphyletic contents of "reptilia" and "sauropsida" are quite different, so I don't think the terms are interchangeable. I would like to significantly improve this article - prominently linking to the reptile page, while explaining the different uses clearly. John.Conway 04:54, 31 January 2006 (UTC)[reply]
Another point, the cladistic definition of Reptilia excludes basal sauropsids, and synapsids, and is therefor very different form the paraphyletic content. The cladistic definition of Sauropsida is only different in that it includes birds. This may avoid headaches if we start using the phylocode. - John.Conway 05:01, 31 January 2006 (UTC)[reply]
Right, but the reptile article is not Reptilia, it's reptile (i.e. a common name for Sauropsida, just as the article is bird and not Aves, though Aves redirects there). The reptile article also explicitly excludes synapsids, so it matches the contents of Sauropsida pretty well.Dinoguy2 13:39, 31 January 2006 (UTC)[reply]
Hmm, can we hold off while I think about this? I'm concerned that the we aren't following any scientific opinion at all here, let alone consensus. John.Conway 14:33, 31 January 2006 (UTC)[reply]

Improving this Article

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We really need to work on this article if it's going to replace reptile as the class rank (at least for extinct animals), as I would like it to. It's currently quite confusing, especially on the cladistic/traditional taxonomy point. We also need to draw the attention of someone that knows about basal sauropsids, because I sure as hell don't. - John.Conway 05:07, 31 January 2006 (UTC)[reply]

One, at least temporary improvement, could be to copy/paste the evolution and anatomy sections from Reptiles, modifying for Sauropsid as needed. This page at the moment focuses solely on taxonomy (which should probably be condensed into sub-headings under one Classification section), and if we're linking this from all the reptile pages, I think a much more comprehensive overview is needed.Dinoguy2 16:18, 2 March 2006 (UTC)[reply]
Reptilia (Linnean) and Sauropsida (cladistic) are not the same. Therefore the latter shouldn't replace the former. e.g. Pelycosaurs and Therapsids are Reptiles, but not Sauropsids. I strongly support retaining both articles, with "reptile" written from a linnean point of view (ectothermic amniotes) and sauropsid from a cladistic point of view (synapomorphies and MRCA) The sauroposid page already contains a historical overview of the term "sauropsid", but needs a good cladistic coverage as well. M Alan Kazlev 10:42, 3 March 2006 (UTC)[reply]
I'm not saying one should replace the other, just that Sauropsida should include more than taxonomy. This is a living class of animal--no other page like it, Linnean or cladistic, focusus purely on relationships. There's usually a great deal on anatomy, ecology, etc. (That said, I'm not sure having separate pages for Linnean and Cladistics is the best way to go. So far we've had a good merge, in my opinion, between the two systems, so why keep a purely Linnean page on "reptile" at all? Because many don't like that that's their common name?)Dinoguy2 14:09, 3 March 2006 (UTC)[reply]
Additionally, at least the last time I checked, the Reptile page included a discussion on the fact that Synapsids are no longer considered reptiles, so that's not really an issue.Dinoguy2 14:11, 3 March 2006 (UTC)[reply]
But the average Joe has never heard of "Sauropsid", while everyone has heard of and is familiar with "reptile". Even current biology books often retain the Linnean system and hence the term Reptile. And while yes it is true that Synapsids are no longer considered "Reptiles" in the cladistic definition of the term, they are still considered reptiles in the traditional system. Also, Birds are Sauropsids, but they are not Reptiles. Ichthyostega is an amphibian in the traditional classification, but a "basal tetrapod" (or even "digit-bearing animal" - cladists disagree on terminology as much as on cladograms) in the cladistic. The two systems of taxonomy are not synonomous; even if they do overlap and agree on monophyletic taxa, they disagree as regards paraphyletic taxa, and attempts to force a uniformity only lead to an artificial and clumsy system. And although the Cladistic system and the Phylocode are indeed gaining ground (and are certainly universal now in vertebrate paleontology!), they still do not represent a universal interpretation in biology as a whole. But if you and other wikipedians who are familiar with issues and problems of phylogony, taxonomy, etc agree that the cladistic and traditional classifications should be merged i'll be happy to go along with the majority :-) M Alan Kazlev 05:10, 4 March 2006 (UTC)[reply]
While I can't speak for everyone, it does seem that the current merged system has been agreed upon. The seperate pages for Reptile and Sauropsid are really the only sticking points for me. My objection is mainly that in similar situations, the common name and the technical name for the taxon are merged under the common name. This is actually a wikipedia (or Project TOL) guideline--common names are used for titles unless no common name exists. Hence, Aves redirects to Bird. The title says Bird, while the taxobox (which is where one would look for technical stuff) says Aves. Everybody wins (except the poor homeless dromaeosaurids ;) ). Now, on Reptile, the taxobox makes no mention of the common name "Reptile" except in the header where common names belong, instead using Class Sauropsida. If the kind of people who bother looking at the taxobox wonder what's up, they can read the portion of the text that discusses nomenclature. In my opinion, this is a better situation than two pages, one for nomenclature and one for everything else, that use two different titles, and contain virtually the same taxa (Synapsids are synapsids, birds are aves, unless somebody goes around changing those taxoboxes to "reptile" and Sauropsida, respectively, but that's one hell of a job and would tee off the bird people to no end I imagine).Dinoguy2 16:35, 4 March 2006 (UTC)[reply]
Okay if it's been agreed upon and is wikipedia policy i'm cool with that  :-) M Alan Kazlev 23:41, 4 March 2006 (UTC)[reply]
I am sorry guys, but I think there are some formating problems in the taxonomy section.. Indentations seem off, but I do not know enough to fix it.

Contradiction - Please help

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How can the following face happen? Sauropsida is a class, isn't it? Fine. Now look on the bottom of the classification- aves, which form a class themselves, happen to be taxonomically beneath Sauropsida. Now tell me- how can a class be classified beneath another class? Did I miss something? Ybk33 22:44, 19 December 2006 (UTC)[reply]

The way that Benton uses the term "class" Sauropsida is paraphyletic--that is, it does not include certain descendants, namely the birds. The indent (I assume) was meant to show that Aves descended from Sauropsids. In phylogenetic taxonomy, which doesn't use ranks, Aves does belong within Sauropsida. I'll try to convert the article to use the two sytems seperately, which is more in line with how we've been doing things on paleo articles. Dinoguy2 03:58, 20 December 2006 (UTC)[reply]
I understood partially. As an editor in another wikipedia, how am I supposed to rank the Sauropsida? As a class? And if I do, how can I do that and rank the aves as class as well at the same time? I am sorry for my nudging, I just have to know what to do with the sorting of those sauropsida. Ybk33 01:56, 21 December 2006 (UTC)[reply]
Actually this shows why the Linnaean and Cladistic (Phylogenetic) methodologies are incompatable. Professor Mike Benton does try to combine the two in a single taxonomic system, and he certainly does a better job than most, but there's still these sort of unresolved problems.
Several options
  • Use the old-fashioned terms Class Reptilia and Class Aves
  • Use the strict phylogenetic approach and scrap the taxonomic hierarchy altogether (instead you can use indenting, or else draw or copy an ascii tree like those on Palaeos and Mikko's Phylogeny Archive)
  • Use the above two but separately, emphasising the differences in each methodology; so they complement each other.
  • Use Benton's "hybrid" version and cite him as a reference (note that Benton is widely but by no means universally recommended; Benton also opposes the PhyloCode. I've exchanged a few emails with him and he's a really decent guy) M Alan Kazlev 02:12, 21 December 2006 (UTC)[reply]
If I use Benton's hybrid, then I want to understand: Does he solve the contradiction I have shown about the aves and the sauropsida (they are both classes)? Or does he not? Ybk33 00:43, 22 December 2006 (UTC)[reply]
Yes he does. They are listed as distinct classes. See this page http://palaeo.gly.bris.ac.uk/benton/vertclass.html M Alan Kazlev 00:51, 22 December 2006 (UTC)[reply]

Move discussion in progress

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There is a move discussion in progress on Talk:Sauropsid which affects this page. Please participate on that page and not in this talk page section. Thank you. —RMCD bot 00:34, 27 March 2024 (UTC)[reply]