Talk:Amniote

message: in the cladogram, having an image of a bird for diapsids might demonstrate diversity better. many other taxa use lizard-like organisms for their images already.  — Preceding unsigned comment added by 96.70.198.37 (talk) 13:55, 27 March 2019 (UTC)
thread_title: proposed image change =

message: The Taxonomy section shows the Class Synasida containing the Order Therapsida, which in turn contains the Class Mammalia. You really can't mix traditional classification and cladistics this way.This needs to organized like Synapsid is. -- Donald Albury 22:55, 5 February 2007 (UTC)
replies: text: Fixed it. Dinoguy2 23:01, 5 February 2007 (UTC)
thread_title:  Problem with Taxonomy section 

message: Erm, we need one. Badly. Samsara (talk • contribs) 14:45, 3 June 2007 (UTC)
replies: text: Do-dom: http://www.tolweb.org/Amniota Samsara (talk • contribs) 14:49, 3 June 2007 (UTC)
thread_title:  No phylogram of amniotes?! 

message: Based on this and related articles, it seems that synapsids and sauropsids are two different lineages of amniotes which have evolved separately and are not directly related to one another. This means that "amniota" is a polyphyletic group, and therefore it is not a valid clade by the standards of modern cladistics. Is this correct?  —Preceding unsigned comment added by 79.179.255.83 (talk) 15:26, 29 March 2008 (UTC)
replies: text: The problem here is that the use of cladistic taxonomy makes it very hard to classify basal organisms, like Casineria, in a meaningful way. While the split between synapsids and sauropsids is a deep one, it does not run all the way to the bottom, and there's always the question of turtles, which may represent an even earlier split. This is the kind of situation that cladistic taxonomy is not well suited to deal with. Petter Bøckman (talk) 09:46, 14 April 2009 (UTC)
replies: text: Cladistic taxonomy, which is almost universally accepted by people working on early amniotes, does not create a problem. Basal organisms are difficult to place into one or the other lineage coming off a node simply because they are basal. This is not a problem to be solved by the erection of artificial categories, but reality.  —Preceding unsigned comment added by Struvite (talk • contribs) 16:13, 9 March 2010 (UTC)

text: The Amniota (proper name) would be polyphyletic only if derived from different amphibians. Polyphyly has to do with their ancestry, not the lineages contained within. Of course the same question can be asked of the Sauropsida and of the Synapsida.  Best ignore most of the cladobabble. J.H.McDonnell (talk) 00:05, 15 September 2010 (UTC)

text: I know that I'm a bit late, but here are my two cents. The short answer: I think not. The long answer: Where is it suggested that Synapsida and Sauropsida are not directly related to each other? As far as I can tell, this and related articles say that Sauropsida and Synapsida are sister taxa, meaning that they are more closely related to each other than to any other clades, with Sauropsida being the clade made up of all amniotes more closely related to birds than to mammals, and Synapsida being the clade of all amniotes more closely related to mammals than to birds. It's true that these two groups contain almost all known amniotes, meaning that the synapsid-sauropsid split happened very early in amniote evolution. However, that doesn't mean that Amniota is polyphyletic at all. Amniota is polyphyletic if and only if the mammalian amniotic egg isn't homologous to the amniotic eggs of birds, of crocodilians, and of lepidosaurs, that is to say, if the forebears of mammals evolved the amniotic egg independently of the forebears of birds, of crocodilians, or of lepidosaurs. In that case, the last shared forebear of mammals and birds (or one of the other groups) would not have laid amniotic eggs (unless one lineage secondarily lost the original amniotic egg and then later evolved it anew, which is rather unlikely, though). However, as far as I know, the amniotic egg was only invented once, namely by animals which were forebears of both mammals and birds, and so, Amniota very likely is monophyletic, not polyphyletic. Also, I haven't found any source claiming otherwise. Have you found any such sources? Kniva Keisarabani the Goth (talk) 10:08, 14 August 2020 (UTC)
thread_title:  Are amniotes a polyphyletic group? 

message: The Out of the swamps external link does not work, when I tried to get on it it said "HTTP 404 not found"  —Preceding unsigned comment added by Phthinosuchusisanancestor (talk • contribs) 21:40, 14 November 2008 (UTC)
replies: text: It works now.Petter Bøckman (talk) 09:48, 14 April 2009 (UTC)
thread_title: Problems with links

message: The ranked taxonomy of amniotes taken from Benton is not really phylogenetic. At best it is a hybrid of the "traditional" system and a phylogenetic classificiation. I don not believe that it is very widely used. The (or a) real phylogenetic classification is the one given in the cladogram: in phylogenetics a cladogram and a classification are one in the same. As written the article also gives the impression that the "traditional" system still is in widespread use. It is not, although it persists in some textbooks.Struvite (talk) 16:26, 9 March 2010 (UTC)
replies: text: You'll find Bentons hybrid system all over Wikipedia. If you wish to argue against it's use (I'm personally not too fond of it either), Wikipedia:WikiProject Amphibians and Reptiles#Paleontological references is the place to speak your mind on this matter. As for the old system, it is very common once you get outside of specialist literature. As such is merit mention. Petter Bøckman (talk) 18:51, 9 March 2010 (UTC)
replies: text:  I don't object to it being mentioned, just to the implication that it is accepted among people working in the field. In the same way a history of chemistry would be incomplete without discussion of the four ancient elements, but would be inaccurate if it suggested that modern chemists still spoke in terms of 'earth' and 'fire.' The same with Benton's system. I'm not saying take it down, I just object to calling it phylogenetic. It is not. As for specialist literature, that's pretty much all there is when it comes to 'amniotes.' It's not a traditional group, like 'birds' and 'fish,' but a category that never has been widely used outside of specialist literature and textbooks. The problem is so few people actively work on amniotes as amniotes that textbook accounts rarely change to accommodate new discoveries and interpretations. Struvite (talk) 22:06, 9 March 2010 (UTC)
thread_title:  Phylogenetic classification 

message: The amniote egg traditionally has been considered a major evolutionary advance that permitted vertebrates to reproduce on dry land, freeing them of the need to return to standing water. I intend to revise this article (with references) to reflect recent challenges to this view, and in particular to point out that 1. we have no direct evidence, and essentially no indirect evidence, of how the first amniotes or their ancestors reproduced. There is no reason to assume that the reproductive mode of modern amphibians is primitive or that the amniote egg evolved from anything resembling a frog egg. Some of the features of amniote eggs that have been interpreted as adaptations to terrestrial reproduction may in fact be primitive. 2. Amniote eggs provide no more protection from dehydration than amphbian eggs, even modern amphibian eggs. Eggs buried in underground nests need no such protection as the water potential of soil in such nests is higher than the physiological water potential of vertebrate eggs. 3. buildup of nitrogenous waste in terrestrial eggs is not the serious problem it often is assumed to be. 4. Terrestrial eggs need no special adaptations for gas exchange. 
It may be best to create a separate section dealing with the amniote egg.
I'm new here and wanted to give a heads up before I make a lot of changes Struvite (talk) 17:06, 9 March 2010 (UTC)
replies: text: As long as you can back up your statements with credible sources, I can't see any problems. It might be a good idea to make a separate article on the amniote egg as you suggested, the two can be merged later if we want to. Petter Bøckman (talk) 18:56, 9 March 2010 (UTC)
replies: text: Thanks for the suggestion. that probably is what I will do.Struvite (talk) 22:07, 9 March 2010 (UTC)
thread_title:  Amniote egg and terrestrial reproduction 

message: In the lede, the first amniotes are described as The first amniotes (referred to as "basal amniotes" or "stem amniotes"). This is misleading, as it indicates the stem group amniotes are limited to to the proper egg-laying animals. While "basal amniotes" is not a very precise term, stem amniota denotes a very wide assemblage, including most of (if not all) of the groups traditionally assigned to Reptiliomorpha, including Seymouria, Eogyrinus and Archeria, not to mention quite a few fossil tadpoles. The labyrinthodont tree is not well understood, and the actual content of "stem amniota" is a matter of some dispute, and may even contain some groups traditionally assigned to Temnospondyli. As such, the term "stem amniotes" is useless, and I have removed it from the lede. Petter Bøckman (talk) 07:09, 4 May 2011 (UTC)
thread_title: Stem amniote?

message: With the Mesosauridae evolving within the Parareptilia (= Anapsida). Sauropsida should be considered a junior synonym of Reptilia.
Tsuji, L. A., and J. Müller. 2009. Assembling the history of the Parareptilia: phylogeny, diversification, and a new definition of the clade. Fossil Record, 12(1): 71-81.
Modesto, S. P. 2006. The cranial skeleton of the Early Permian aquatic reptile Mesosaurus tenuidens: implications for relationships and palaeobiology. Zoological Journal of the Linnean Society, 146: 345-368.
Ronald Van Heest (talk) 14:07, 5 September 2010 (UTC)
replies: text: No, Sauropsida can't be synonymised with Reptilia. Reptilia is defines by traits, Sauropsida by phylogeny. Appart from the fundamental difference in approach, the content is stil different. While Casineria  is a reptile, it is not a s Sauropsid, and the mammal-like reptiles are are excluded from Sauropsida, while birds are included (unlike in Reptilia). The two are fundamentally different systematic units.--Petter Bøckman (talk) 08:19, 6 September 2010 (UTC)
thread_title:  Sauropsida, a junior synonym of Reptilia 

message: The third paragraph of the lede says: The first amniotes, referred to as "basal amniotes", resembled small lizards and evolved from the amphibian reptiliomorphs about 312 million years ago,[2]. This doesn't look right. The conventional date is 340 mya. The statement is not supported by the source, which gives 312-330 as the date for the Saurapsid/Synapsid split, which would be the crown group. Zyxwv99 (talk) 04:30, 7 March 2015 (UTC)
replies: text: Never mind, I figured it out. The more recent date is for crown amniotes (most recent common ancestor of living amniotes) while the 340 mya date is for the apomorphy-based definition (nearest common ancestor of two fossil genera that each have enough items on the checklist of fossil bone characters to qualify as a bone-amniote, i.e., something paleontologists can measure). Zyxwv99 (talk) 20:43, 22 May 2015 (UTC)
thread_title:  312 mya 

message: I am confused about the references to Infraclass. For example, it looks as if under the clade "Infraclass Diapsida" there are "Infraclass Neodiapsida" and "Infraclass Lepidosauromorpha". Should there be a different designation for the clade "Diapsida"? TomS TDotO (talk) 21:30, 8 August 2020 (UTC)
replies: text: Also Infraclass Ichthyosauria. This is a peculiarity of Benton's classification schemes. He will repeat Linnaean ranks in the sequence. —  Jts1882 | talk  07:53, 9 August 2020 (UTC)
thread_title:  Infraclasses