Talk:Amargatitanis

GA Review

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

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

Reviewer: Jens Lallensack (talk · contribs) 15:04, 2 September 2023 (UTC)

Hi again, and see comments below:

• My biggest concern is accessibility, and here the article needs a lot of work. Reduce technical language, link all terms, explain what you can. Just an an example, the sentence Cortical bone in this element also has an External Fundamental System, which was more organized than earlier CGMs, a characteristic associated with maturation is incomprehensible unless you know what an EFS actually is. Other examples are less severe but still, I think the whole text needs to be reworked towards comprehensibility for the non-expert.
• Amargratitanis – sure about the spelling? Same with "Amargra"
  • Fixed
• partially due to on the anatomy of MACN PV N34 and N51 – grammar issue, and I would repeat the information here instead of just giving the specimen numbers that the average reader won't remember.
  • fixed
• long and 3.5 metric tons – add "in weight"?
  • fixed
• higher browsing titanosaurs – the linked article does not discuss "high browsing", so only "browsing should be linked".
  • fixed
• according to the book Dinosaur Facts and Figures: The Sauropods and Other Sauropodomorphs – Why providing the book title in-text? Also, we had several discussions already whether or not this is a reliable source or not. Some called it a "children's book", in which case it would be a questionable source because the provided estimates might not have been intended for scientific use.
  • These are the only available size estimates.
• et al – lacks a dot, and I would replace with "and colleagues" anyways to avoid the technical term.
  • fixed
• removed MACN PV N34 and N51 from the holotype material – What is this material instead? Indeterminate titanosauriform or something? Could be mentioned.
  • fixed
• their prezygapophyses and a lamina – which lamina? Between which processes?
• (front to back)band – some issue here
  • fixed
• Centra of the caudals are – add "The"
  • fixed
• The iliac peduncle – this, and others, could better be linked to the Glossary of dinosaur anatomy, where this very term is defined, not just "peduncle".
• Due to damage, much of the femoral head is incomplete – If a bone is incomplete, then damage is always the cause, right? So what kind of damage is it? Damage caused during preparation?
  • fixed
• low and located at the middle part of the femur – further down or up compared to its relatives?
  • fixed
• A metatarsal is also preserved, but only represented by its distal half. Instead of flat, the articular end is very rugose for conjugation with the tibia. – This does not make any sense, please check.
  • fixed
• or lacked titanosaur traits – grammar issue. Who or what "lacked"?
  • fixed
• Features of the femur, astragalus, and other elements led Gallina (2016) to group it with Dicraeosauridae. His phylogenetic analysis of the family found Amargatitanis to be sister taxon to Suuwassea in a subgroup of basal dicraeosaurids. More cladistic studies reinforced this finding. A 2016 re-evaluation by Pablo Ariel Gallina classified Amargatitanis as a dicraeosaurid. – I see more than one issue here, please check. But the main thing I don't understand is what this first 2016 publication is, why is it not cited?
  • fixed
• in polytomy with Pilmatueia – not only with Pilmatueia (otherwise it wouldn't be a polytomy)
  • fixed
• primitive – use "basal" and explain the term; "primitive" can be misleading, as these taxa were not literally "primitive".\
  • fixed
• of its neck – "their neck"?
  • fixed
• Gallina (2016) – I don't personally have issues with such notation, but other Wikipedians do have. Another issue is consistency with other articles (where we always write "in 2016, Gallina …" or similar). Wikipedia is for the general reader, and it makes sense to spell these things out to make it readible.
  • fixed
• In general, I think the article still has many careless errors that could have been eliminated by copy editing before submission. However, it is a short article, so I was able to list all the individual issues here without needing too much time. --Jens Lallensack (talk) 15:04, 2 September 2023 (UTC)

• Quick comment regarding the recent fixes: If you want to link to the glossary, use the syntax {{Dinogloss|term}} or {{Dinogloss|actual term|display term}}. It can deal with different variants and synonyms of the term, but please still check if the link works. Thanks. --Jens Lallensack (talk) 20:27, 3 September 2023 (UTC)

  All implemented, sorry for the amount of errors, I nominated this article prematurely. AFH (talk) 20:42, 4 September 2023 (UTC)

• Looking good to me! I see two things that still need some work:
• Its femoral head is well-preserved, which is laterally shifted – it is not easy to understand what "laterally shifted" means here, this could be reworded so that a general reader can understand.
• I think the histology section still needs work. I think it needs some introductory sentences explaining to the reader how this stuff works (counting lines of growth similar to counting growth rings of a tree, etc.). Then, we need to explain the terms, since without such explanation it is impossible to understand (as I mentioned earlier, EFS is not even linked). I also do not understand why you mention cortical bone only in association with the EFS, when the other mentioned features should also be in cortical bone as far as I know? --Jens Lallensack (talk) 01:32, 5 September 2023 (UTC)
  • I just made an attempt of a similar section in the Amargasaurus article. --Jens Lallensack (talk) 02:16, 5 September 2023 (UTC)

    I changed it, this better? AFH (talk) 14:15, 5 September 2023 (UTC)

Better, but I see some new issues with your recent additions.

• Regarding the femoral head, it is not "slightly bent laterally", it is still bent medially, right?
• The study sought to calculate the number and spacing of lines of arrested growth – You count them, no calculation involved.
• The study sought to calculate the number and spacing of lines of arrested growth – Should "lines of arrested growth" be replaced with "cyclical growth marks", since this is what they counted in Amargatitanis?
• maturation and sexual maturity. – secual maturity is a type of maturation. --Jens Lallensack (talk) 14:44, 5 September 2023 (UTC)

fixed. AFH (talk) 21:01, 7 September 2023 (UTC)

• Cool! I think it should be ready for promotion now, if @Ornithopsis: does not have any more comments? The last issue I see now are the wikilinks, which are a mess. For example, many bones are not linked in the Discovery section but are linked later on. Could you please have a look at this. --Jens Lallensack (talk) 22:10, 7 September 2023 (UTC)

  Fixed links AFH (talk) 11:35, 8 September 2023 (UTC)

  The description section still has several issues:

  • Amargatitanis was estimated to be around 12 meters (39.7 feet) long and 3.5 metric tons (3.9 short tons) in weight. However, it was later thought to be 11.406 metric tons (12.573 short tons) in weight by Benson and colleagues in 2018, placing it on the lower end of South American sauropod sizes. Given that the first source is from 2020 and the second is from 2018, saying "it was later thought" is incorrect, and the phrasing implies that one work's estimate was a response to the other. I would phrase it as something like "Amargatitanis has been estimated to be around 12 meters long[1] and between 3.5[1] and 11.4[2] metric tons in weight", to be more concise. Also, in my opinion the Dinosaur Facts and Figures books are not reliable sources, as there are conspicuous errors on nearly every page.
  • The two caudal (tail) vertebrae correspond to the anterior part of the tail. Only one of the preserved caudal vertebrae is an anterior caudal; the other one is a middle caudal.
  • Their neural canals are half the height of the neural spine seems to be a misunderstanding of Gallina: "The neural arch extends dorsally two times the height of the neural canal"; in this context "neural arch" means the arch excluding the spine, which is only partially preserved anyway.
  • ...and bear deep fossae on their lateral faces, a distinct trait of the genus. The phrasing of this sentence implies the fossae are on the neural canal, which is not correct. The fossae being referred to are presumably the prezygapophyseal centrodiapophyseal fossae, which are on the anterior face of the neural arch and not unique to Amargatitanis; it is the presence of a thin vertical lamina within the prezygapophyseal centrodiapophyseal fossa that is claimed to be unique to Amargatitanis.
  • The centra of the caudals are short anteroposteriorly (front to back) and tall dorsoventrally (top to bottom) For what it's worth, this basically reflects what part of the tail the preserved vertebrae are from, as more anterior caudals are shorter anteroposteriorly and taller dorsoventrally and more posterior caudals are longer and lower.
  • The ilium is longer than wide, another trait found in its relatives. No ilium is preserved.
  • Its femoral head is well-preserved, which is slightly bent laterally like in other diplodocoids. I am not sure what this is referring to.
  • The articular face is flat and triangular but has a low process. This should say "... low ascending process", the ascending process is the name of a particular structure.
  • Its posterior end bears a deep, crescent-shaped fossa and two foramina (pits in bone) which are not found in other genera. The fossa and foramina are typical of sauropods, it is their arrangement that differs: "Although the presence of a posterior fossa with foramina is present in other neosauropods astragali (e.g. Apatosaurus, Amargasaurus, Brachiosaurus, Camarasaurus, Bonitasaura), the peculiar morphology and arrangement of the fossa and foramina in Amargatitanis are recognized as an autapomorphy of the taxon."

  In general the description section seems to be trying to describe a lot of irrelevant anatomical minutae while minimizing the use of technical terms, which has the effect of producing a description that is neither interesting to a casual reader nor informative to someone familiar with sauropod anatomy. Ornithopsis (talk) 12:55, 8 September 2023 (UTC)

Thanks for your comments, which are valuable, and many of thouse I should have seen myself!

• Regarding the "Dinosaur Facts and Figures" book, I already commented on. I think we have a statement from FAC that they won't accept this source there, and I didn't saw a good argument why this book can be considered a "high quality source". In a recent article of mine (Ohmdenosaurus), which is currently at FAC (and still lacks a review btw), I choose not to include it, even though the only other existing size estimate is very outdated. So yes, I think we need to part with that book, unless there is a solid argument for it that I overlooked.
• Regarding the general criticism (description not informative to anyone): This is a point that, I think, applies to many of our dinosaur articles. I partly see this problem, too, and I am not a fan of our description sections either. We are writing for the general reader, so maybe we should generally keep them shorter and focus on few points we want to convey to the reader. But then, this article is only following current standards (and therefore can't really be blamed in this GAN), and I personally think it is not that bad in this particular aspect.
• I just see that Augustios didn't address my previous comment on the sentence Its femoral head is well-preserved, which is slightly bent laterally like in other diplodocoids. – This is still incorrect! Of course it is bent medially like in any other dinosaur. --Jens Lallensack (talk) 13:36, 8 September 2023 (UTC)

I might retract this article from promotion. I realize now that the subject and my article on it are not up to my or other standards. AFH (talk) 13:03, 10 September 2023 (UTC)

• The fossils came from the Barremian-aged Puesto Antigual Member of the La Amarga Formation, being around 129 to 123 mya (million years old), though they were later mistakenly assigned to the Pichi Picún Leufú Formation.[1][2] – The assignment to the Pichi Picún Leufú Formation comes from Bonapartes notebook, so it appears to be the initial assignment? I consequently don't understand what you mean with "later". --Jens Lallensack (talk) 18:56, 8 September 2023 (UTC)

  I don't see this text anymore. AFH (talk) 13:04, 10 September 2023 (UTC)

Additional comments

I also have a few comments to add:

• In the lead paragraph, you say that it lived in an ecosystem with titanosaurs, but in the paleoecology paragraph you say it lived alongside basal titanosauriforms. I believe the latter is correct; if I remember correctly, reports of titanosaurs in the La Amarga Formation were based on Amargatitanis itself.
  • fixed
• ] It was originally assigned to the group Titanosauria, partially due to on the anatomy of MACN PV N34 and N51, but a 2016 reanalysis of the fossils demonstrated that Amargatitanis was instead a dicraeosaurid dipolodocoid. The study, authored by researcher Pablo Gallina, also removed MACN PV N34 and N51 from the holotype material and considered only the dicraeosaurid bones to be from the genus These couple sentences could probably be rephrased and condensed, in particular, "...a 2016 study by Pablo Gallina..." would be a lot more concise than "...a 2016 reanalysis of the fossils...This study, authored by researcher Pablo Gallina..."
• Their neural canals are half the height of the neural spine, with having deep fossae on their prezygapophyses and a lamina, a distinct trait of the genus. Having a lamina is not unique. Sauropod vertebrae have all kinds of laminae. What's special about this lamina?
  • fixed
• Compared to related genera, the fourth trochanter is low and located at the middle part of the femur, another unique characteristic. Gallina (2016) actually says that the shape and position of the fourth trochanter is like that of other flagellicaudatans; it is not unique to Amargatitanis.
  • fixed
• Due to damage, much of the femoral head is incomplete. This is incorrect, Gallina says the femur is complete except for damage to the tibial condyle. The femoral head is clearly more or less complete in the photos of the specimen.
  • fixed
• An incomplete right tibia belongs to the holotype, though it too is missing some of its anatomy. This is redundant; the tibia being incomplete already implies that it is missing something.
  • fixed
• Windholz et al. (2022)[1] argued that South American dicraeosaurids, including Amargatitanis, probably formed a clade; I feel this needs to be mentioned and probably should be shown with a cladogram. (Full disclosure: I have something of a conflict of interest here, because in 2020 I presented results at SVP that agree with Windholtz et al.'s results in this regard)

That's all I have for now.Ornithopsis (talk) 18:59, 2 September 2023 (UTC)

• • Fixed all of the above

Going forward

Hey, folks: My personal accessment now is still that the article is very close to promotion pending some minor issues only. @Augustios Paleo: No need to retract this, really. You did a great job with addressing all of our comments, and this article underwent greater scrutiny than is usually the case at GAN.

@Ornithopsis: Thank you for your efforts you put into this, but I worry that our lead author might be frustrated. It might have been prudent to ask them first before re-writing the entire description section. I generally like your new text (although it needs some accessibility improvements), but Augustios section was not bad as well apart from some inaccuracies and mistakes. Your opinion seems to be that this section should focus on diagnostic features, and that insignificant and general anatomical features do not help anybody and are better left out. As I said, I partly agree, but the problem is that your changes are not according to the consensus of our WikiProject (all of our recent FAs include a sample of features that are not diagnostic). I wonder if it might have been better to start a discussion at the WikiProject about this first?

Augustios: Are you happy with the new section? If so, I will try to improve accessibility and promote the article. If not, please let us know and we surely can find a solution. Thank you. --Jens Lallensack (talk) 13:53, 10 September 2023 (UTC)

My apologies if my edit was presumptuous; I felt it would be easier to make the changes myself than to continue nitpicking. I probably was overzealous in trimming the description section; in addition to diagnostic features, for instance, it is probably worth mentioning some of the ways that Amargatitanis resembles dicraeosaurids and not titanosaurs, given the historical confusion over its classification, so I've added some more information on that into the description section. Other kinds of information other than diagnostic traits that I think are worth mentioning are traits that have an obvious impact on the overall appearance of the animal, and traits that have some reported functional significance, but unfortunately there isn't much to say about Amargatitanis in either regard. If there's any information that I removed that either of you feel should be added back, feel free to do so. Ornithopsis (talk) 15:53, 10 September 2023 (UTC)

Thanks for the additions; I am personally very happy with the selection of features now, let's see what Augustios thinks. The middle paragraph lacks a source; I also wonder if the size estimate for Amargasaurus is really relevant here (I found it slightly confusing). The last remaining issue I see here is the accessibility (per policy, we are required to avoid technical language as much as possible). In our FAs, we usually simply replace the directional terms (lateral, medial, proximal, distal) with "outer", "inner", "upper", and "lower". Alternatively, we could explain them at first mention if this seems to imprecise. Some other terms might better be explained, too. Before I make changes myself, please let me know what you think. --Jens Lallensack (talk) 17:12, 10 September 2023 (UTC)

I mentioned the mass estimates for Amargasaurus to provide context for the mass estimate given for Amargatitanis; since only one mass estimate is available for the taxon in the peer-reviewed literature, it seemed appropriate to qualify that estimate by pointing out the broader context of how mass estimates can vary depending on the method used. As far as accessbility is concerned, I think we should keep in mind that the description section, by necessity, goes into considerable technical detail, and that detail will exist even if we swap out words for more colloquial ones. I don't think that basic anatomical terms are any more technical than required by the nature of the topic. Of course, the section can be rephrased to be more clear to a casual reader without an unacceptable loss of precision, feel free to do so; I know my writing skills are not the best. Ornithopsis (talk) 18:04, 10 September 2023 (UTC)

I just did a copy edit trying to improve accessibility. Btw, I just noticed you removed the section about the histology; what was the problem with it? --Jens Lallensack (talk) 18:45, 10 September 2023 (UTC)

I moved the main piece of information from that section (that the holotype individual represented a mature individual at least nineteen years old) to the "Fossil record" section. I felt it was unneccesary to dedicate an entire section to a blow-by-blow description of a single study, and that there isn't much else to say about the paleobiology of the taxon in general. Ornithopsis (talk) 19:46, 10 September 2023 (UTC)

I would argue for bringing this section back. It adds diversity and balance to the article. Note that the article is itself based mostly on a single source only, so I see no problem of having five sentences on this one source. Even though the text you removed contains little additional information, it provides context that the reader might need to appreciate the age assessment. Jens Lallensack (talk) 21:17, 10 September 2023 (UTC)

@FunkMonk: Can we have your opinion here please? The question is if we should keep the paleobiology section (still present in this version: https://en.wikipedia.org/w/index.php?title=Amargatitanis&oldid=1174569303), or if this should be reduced to only a single sentence. Thanks. Jens Lallensack (talk) 22:19, 11 September 2023 (UTC)

I'd also suggest keeping the section; especially with taxa that have little published on them, it is essential that we cover what is known about them. Comprehensiveness and context are important GAN and FAC criteria, which is also why I see little reason to remove more general descriptive information if it helps give the reader a better idea of how the animal looked. Is a taxon diagnosable from a single knob on the femur? Does that mean we should ignore every other of its features just because it's shared with related taxa? Of course not. We aren't even that exclusive when it comes to extant taxa. A line should be drawn somewhere, of course, but again, comprehensiveness/context are crucial criteria. FunkMonk (talk) 22:39, 11 September 2023 (UTC)

The only relevant piece of the paleobiology section was retained, but moved to the fossil record section because it is a specific fact about the holotype individual, not the paleobiology of the taxon in general. When I said that I felt it was unnecessary to dedicate a section to a single study, I was not talking about how the section only had a single source, but that the section came across as a description of the study itself rather than a description of the paleobiology of Amargatitanis. What I kept in the article was the following:

• This specimen represents a mature individual that was at least 19 years old at time of death,

If you think additional context is necessary, that sentence could be slightly expanded:

• This specimen represents a mature individual that was at least 19 years old at time of death, as determined by counting the number of annual growth marks preserved in the femur,

I don't see the need for much more information than that.

As far as diagnostic traits go, I never argued that the section should be restricted to diagnostic traits only; what I'm arguing for is that anatomical traits mentioned need to be in some way meaningful. That can mean diagnostic traits, traits relevant to its phylogenetic position, functionally significant traits, traits that significantly impact the appearance of the animal, and more. However, the description section should not just be an indiscriminate compilation of any anatomical detail mentioned in an osteological description of the taxon. Ornithopsis (talk) 00:34, 12 September 2023 (UTC)

Hmm I don't really see how it is "a description of the study itself". Only the first sentence is about the study setup. The second sentence is context for the general reader to explain how this stuff works. The third and fourth sentences provide the results of the study. Isn't this exactly how we usually do it in other dinosaur articles as well? And do you feel strongly about it – or may I add this section back-in (I would rename it to "Life History")? Jens Lallensack (talk) 00:48, 12 September 2023 (UTC)

I'd count the first two sentences as mostly describing the study setup. If we must have the section, I would rephrase it to something like: "The type specimen of Amargatitanis was determined to have been at least 19 years old at the time of death by a study that counted the number of cyclical growth marks in the femur (similar to counting the growth rings of a tree). The last six growth lines were closely packed, forming an external fundamental system, which indicates that the individual had attained its adult size. The bone had undergone remodeling, another trait indicating maturity." Ornithopsis (talk) 01:56, 12 September 2023 (UTC)

I guess where I'm coming from is that, as far as Amargatitanis is concerned, the important thing is that this study establishes a fact about the holotype specimen in particular that does not say much about the paleobiology or life history of the taxon in general, so I think that it really only needs to be mentioned as part of describing what the type specimen represents. Furthermore, I, personally, find it tedious when I want to learn something about a topic and find that article does not directly state relevant information, but instead gets to it in a roundabout way such as what's done in the paleobiology section. Of course, if the study is in itself interesting and notable enough to merit coverage in its own right, that's different, but this is not such a study; it's a bog-standard histology study very similar to studies done of countless other taxa. I really think the article only needs the fact that the type specimen was a mature individual at least nineteen years old, although the article on skeletochronology might be appropriate to link to (although it currently needs work), so that a reader interested in learning more about how the ages of fossil specimens are estimated can get a fuller understanding of the topic. Ornithopsis (talk) 04:05, 12 September 2023 (UTC)

I see your point that the paragraph is not strictly about paleobiology but about the holotype specimen. We could solve this by either adding some general information about sauropod growth (which is provided in that paper, in the context of Amargasaurus/Amargatitanis) or have it as a paragraph in the "fossil record" section. In any case, I still think we should keep this text. That the study is "boring" should be irrelevant here; it is one of the very few studies that specifically discusses Amargatitanis in greater detail, so we have to give it due weight. Given how little we can report on this topic, the mere fact that histology has been done on this genus in a separate study is already worth mentioning in my opinion (and if we do, we should also explain how it works, which is all this paragraph does). Jens Lallensack (talk) 04:23, 12 September 2023 (UTC)

Yeah, I don't think it matters much if we think something is boring or not, in this case, the GAN criteria trump personal preferences, and they require that the literature on a subject is comprehensively covered in summary style, which this clearly is. One issue is that the MOS discourages single paragraph sections, though. FunkMonk (talk) 07:45, 12 September 2023 (UTC)

Ok, I greatly expanded the section and put it back in, hope this solves all of the concerns both of you pointed out. I continue to start the section by introducing the study including author names, to be consistent with the style used elsewhere in the article. Jens Lallensack (talk) 12:10, 12 September 2023 (UTC)

It's okay it's just the article was nominated by myself prematurely. I have no frustrations, I am thankful that you have these criticisms as the goal of these reviews is to improve articles. If you believe it's okay, then we can keep on with the review. What happened to the histology section? AFH (talk) 19:35, 10 September 2023 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.