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Well birds are dinosaurs I guess. But saying that crocodilians are related to birds is like saying we're related to...so something really distantly related. —Preceding unsigned comment added by 128.135.113.75 (talk) 19:11, 26 October 2009 (UTC)
Dinosaurs are NOT birds. Birds however, are dinosaurs because they evolved from a subgroup of theropods called the Maniraptora. Crocodilians are the closest relatives to birds because they are both archosaurs. I know this message is late, but I had to say something about it. Mistermister93 10:13, 14 January 2011 — Preceding unsigned comment added by Mrmister93 (talk • contribs)
Source?
"Eusuchia, a modern clade which includes the crown group Crocodylia, first appeared in the Lower Cretaceous of Europe. Isisfordia duncani lived approximately 95 to 98 million years ago, during the Cenomanian epoch of the Upper Cretaceous. Isisfordia is the second oldest known eusuchian, and the earliest crocodilomorph yet found in Australia."
I cant find evidence that Eusuchia first appeared in Europe, furthermore if Isisfordia duncani is the second oldest known eusuchian, whats the oldest? Counter to this I found this article stating that crocodilians first appeared in Australia.
http://www.uq.edu.au/news/?article=9853
Hylaeochampsa vectiana is the oldest known eusuchian. It was found on the Isle of Wight in the Vectis Formation. This makes it more than 110 millions years ago, and thusly making it the oldest known eusuchian. However, the study by Salisbury et al, finds Isisfordia to be more basal than Hylaeochampsa. They thereby infer that Eusuchia evolved in Gondwana, rather than on any of the northern continents. Which may be the case, or Isisfordia could have migrated to Gondwana. More basal eusuchians need to be found until we "know" were they originated. Mark t young14:22, 24 March 2007 (UTC)
Source Format
I just added a really good general source on shunting in reptiles, as I corrected some inaccuracies in the "Internal Organs" section. I listed it as a journal source, and I haven't been able to successfully add a link to the author's webpage, where a PDF of the article is available. (When I try to do it with the template, I only get the last name, not the first.) Anyway, Jim Hick's website is here [[1]]. I admit that my first attempt at re-writing the paragraph resulted in some sub-standard prose. I strongly suggest that people read that article before editing on shuts, though, because it's really easy to read and is a good review. Enuja20:02, 16 April 2007 (UTC)
Lead mention of Crocodylomorpha
There is already a link of Crocodylomorpha in the taxo-box; isn't that enough? I'd like to reserve notes at the top of the page for things that people will find useful when they arrive at the page; almost no-one, I think, would be looking for Crocodylomorpha, and if there were, they would be able to find it in the taxo-box. Am I missing an important reason to put it up top? Enuja01:59, 17 April 2007 (UTC)
I don't really know what these two sentences are doing in this article.
Mammals, too, have adapted to this body plan at least once in history. One ancestral whale family, the Ambulocetidae, were aquatic predators living in rivers and lakes, and they filled an ecological niche similar to the crocodilians.
Anybody think that belongs? If so, could you edit it to flow more smoothly and flow more smoothly from the previous sentence? If not, I'll just delete it, but I didn't want to delete a link to another article if others think that it is relevant. Enuja04:45, 20 April 2007 (UTC)
Differentiation
The section on the differences between alligators and crocodiles needs to be much improved. To say that they are as different as humans are to gorillas is saying nothing. They are of the same family, right? So, tell me how they are different. They look alike, they walk alike, so please explain their differences. JJ23:46, 20 April 2007 (UTC)
Differences between alligators and crocodiles
Per discussion on both articles talk pages, I have merged this section in here to keep all the information in one place and not maintain two parallel sections. I have added a link from the top of both articles to this section disambiguation style so it is still easy to find from both independent articles. Mfield (talk) 15:48, 17 June 2008 (UTC)
A user has just added this section back into the article, citing as justification this 5-year-old decision. While that old discussion may have some merit, and may influence choices on the shape of the article, it cannot be allowed to override all subsequent decision-making. It might or might not be appropriate to have a differences section here, and if it is appropriate, such a section might or might not resemble the poorly-cited existing section. Updating in some form appears to be necessary. If we do remove the section, we'll need to remove the hatnote link from Crocodile (and maybe other Allig-articles also). Chiswick Chap (talk) 15:18, 26 October 2013 (UTC)
Navbox?
I was thinking about creating a navbox to quickly jump around all the species, and also include related articles. Anyone else think this is a good idea? StevePrutz (talk) 01:44, 24 June 2008 (UTC)
I noticed there is inconsistency in some croc article titles. Some capitalize the second part of a common name (e.g. Freshwater Crocodile), while others do not (e.g. Philippine crocodile). I believe the latter is better for searching. Is there a standard for herps? StevePrutz (talk) 23:26, 26 June 2008 (UTC)
the birds wikiproject uses caps for accepted common names (this seems to be the broader consensus in ornithology as well). the Reptiles & Amphibians wikiproject standard for the Tree of Life project, unless i'm mistaken: Wikipedia:WikiProject Tree of Life#Article titles. Mammal articles pretty much stick to one or the other (upper or lower case), depending on what the format was before the question arose. if there hasn't been some discussion over what's what, it may be best to just go that route till consensus has been established by the wikiproject. i know that's late, but hope it helps.... - Μετανοιδ (talk, email) 00:59, 31 July 2008 (UTC)
I've reverted it, the image switched in is already in the article in the differences section. Plus I have added clarification to the lead that Crocodilia covers the Alligator and Crocodile sub families for anyone who doesn't notice the different word or cannot be bothered to read the article. Mfield (talk) 15:17, 3 August 2008 (UTC)
I don't think so - there's only 23 species in 7 genera, so it's not exactly a massive group. If you want to make a list, go to Anolis - the page would be much better if that list of species were just on a list page. Mokele (talk) 20:54, 22 October 2009 (UTC)
Last I heard, they were different but nested groups, with the only members of crocodylia who aren't in crocodilia being some extinct forms. But crocodilian taxonomy, especially including extinct species, is nothing short of a nightmare. It's probably changed about 4 times since I heard that. Mokele (talk) 11:59, 16 April 2010 (UTC)
I'm agree, this is a nightmare. Recently i found a paper from Martin & Benton (Syst. Biol. 57, 2008) that comment: "For clarity, we suggest that the term Crocodylia should be used" (...) “Crocodilia” has been widely used in textbooks and defines exactly the same thing as Crocodylia: Protosuchia, Mesosuchia, and Eusuchia. Reasons for preferring the usage of Crocodylia over Crocodilia are expressed by Dundee (1989)." I don't have Dundee's paper to confirm the reasons for preference (Dundee H.A. 1989. Higher category name usage for amphibians and reptiles. Syst. Zool. 8:389–406). Crocodylia is widely used in recent paleontological papers, and this cause my doubts about the correct order's name. Burmeister (talk) 21:23, 16 April 2010 (UTC)
Heart Chambers
Crocodilia have five heart chambers. The four everyone thinks of, and the sinus venosus. Although the sinus venosus is reduced, it is still a chamber. Blood enters the sinus venosus before it enters the right atrium. — Preceding unsigned comment added by 97.90.159.19 (talk) 05:10, 26 May 2011 (UTC)
Intro unclear
The present introductory paragraphs are these:
Crocodilia (or Crocodylia) is an order of large reptiles that appeared about 84 million years ago in the late Cretaceous Period (Campanian stage). They are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria.[1] Members of the crocodilian total group, the clade Crurotarsi, appeared about 220 million years ago in the Triassic Period and exhibited a wide diversity of forms during the Mesozoic Era.
Although the term 'crocodiles' is sometimes used to refer to alligators, caiman, and gharials, or even to their distant prehistoric relatives the marine crocodiles, a less ambiguous vernacular term for this group is 'crocodilians'.
That is unclear. Is there a group of animals called "crocodiles"? I'm not joking. I don't know — and I can't tell from those paragraphs. I don't mean "crocodilians"; I mean "crocodiles." Do "crocodilians" include not only alligators, caiman, and gharials but a group of animals called "crocodiles"?108.36.209.26 (talk) 04:20, 28 February 2012 (UTC)
Temperature of the water and the air
Which temperature does the croc need to survive? I know they live in the tropical areas but don't know the limits that this animal can tolerate. Regards,Andres — Preceding unsigned comment added by 190.192.164.156 (talk) 20:45, 16 December 2012 (UTC)
I think that depends on the species. Chris Lavers reports in his book "Why elephants have big ears" that alligators can survive a winter in a frozen lake with only the nostrils peeking out of the ice (I think the ice should not be too thick). check it out, its really a great book. 178.190.48.14 (talk) 22:10, 18 December 2012 (UTC)
Crocodilians have double armour?
"There are small plates of bone, called osteoderms or scutes, under the scales. … The rows of scutes cover the crocodilian’s body from head to tail, forming a tough protective armor. Beneath the scales and osteoderms is another layer of armor, both strong and flexible and built of rows of bony overlapping shingles called osteoscutes, which are embedded in the animal’s back tissue"
Added in a few citation needed in the Sensory Organ section, but the entire article can benefit with citations, as they are quite sparse. I'd do it, but my time is rather limited due to familial health issues.Wzrd1 (talk) 14:49, 30 September 2013 (UTC)
Going forward
Looks like this article is taking shape quicker than I expected! Here are some things that I think need to be done before we get this to GA and eventually FA.
A "growth and mortality" subsection. I work on it this week.
Conservation should be expanded a little to include information on the plight of endangered/threatened species (e.g. gharial) and success stories (e.g. American alligator).
Had a go.
"In popular culture" should be expanded a little. I'll get to this.
Not too much then, and not all recent or western. We could probably put an Elephant's Child image on Commons - book was 1902, and Kipling died 1936 so image is PD-old-70 for UK and book is PD-1923 for USA. Chiswick Chap (talk) 16:57, 3 November 2013 (UTC)
"Popular culture" is typically recent and western. We have plenty of examples of historical and non-western depictions in the other sections. Maybe I'll find examples of crocs in anime. LittleJerry (talk) 00:26, 4 November 2013 (UTC)
No doubt it is, but it's a recentist bias all the same (WP:OTHERSTUFFEXISTS). There are good examples from popular cultures already in the article, with more in Ross etc if needed. We should not have more 20th/21st century stuff than in other centuries, really; at least we should work to keep it short. Chiswick Chap (talk) 16:30, 4 November 2013 (UTC)
Oh and I also think we could come up with enough information to make "respiration", "circulation" and "digestion" into separate subsections. LittleJerry (talk) 20:28, 29 October 2013 (UTC)
Ross and Kelly page refs: a page range should be consistently indicated with "pp. " (at the moment, it's sometimes "p. 123–125" which isn't right). Chiswick Chap (talk) 04:41, 30 October 2013 (UTC)
Do we have the subsections in the right places? Why is locomotion under Morphology and physiology (a mixed bag of a heading, surely) not under Behaviour and life history (another mixed bag)? Why is ecological role under behavior and life history - it's not really either. Perhaps we can do better. Chiswick Chap (talk) 14:52, 30 October 2013 (UTC)
Alright, I just ordered the Wylie book so I'll be able to do add information on crocs in pop culture. In the meantime, I'll also add information on visual communication. I also think we could add a little more information on biting. I've hear that in slender snouted crocs, the pressure is at the back of the mouth while in broad snout ones, the pressures is highest at the tip. However, I don't know if the Erickson paper states this as it gets to technical. LittleJerry (talk) 22:09, 3 November 2013 (UTC)
My Ross book has a number of sections on "Crocodilians and humans" which I have not even looked at as I thought you two had covered the different aspects. There are chapters entitled "Mythology, religion, art and literature", "Attacks on humans", "Crocodile skin products", "The trade in crocodiles", "Farming and ranching" and "Conservation and management". Do you want me to work on any of these topics? Cwmhiraeth (talk) 07:35, 4 November 2013 (UTC)
Maybe you can expand on attacks on humans and make it a section of its own. In addition, could you summarize farming and use of products? I also now think that "Humans relations" should be renamed "Conservation and management". LittleJerry (talk) 15:48, 4 November 2013 (UTC)
You mean promote the 'Attacks on humans' section? Yes, why not, to move it out of the new 'Conservation and management'? But Ross is already over 20 years old, so it shouldn't be the sole source on these topics as much has surely changed. Chiswick Chap (talk) 16:30, 4 November 2013 (UTC)
I also notice this statement in the article "However, early in the 1970s, more than 2 million wild crocodilian skins of a variety of species but mainly Caiman crocodilus had been traded, driving down the majority of crocodilian populations, in some cases almost to extinction." This disagrees with the page on Caiman crocodilus which states that the skins of this particular species are unwanted. Cwmhiraeth (talk) 07:35, 4 November 2013 (UTC)
It came from Adams's book as cited. But everyone can be wrong. It is possible that part of a sentence was missing in the book's text as printed, near the "but mainly" clause. Or the Caiman article is referring to a different time period. Chiswick Chap (talk) 16:30, 4 November 2013 (UTC)
I guess the main thing we can do know is make sure the citation format is consistent and there or no duplinks. I'll find someone who can review this for GA who can prepare it for FA. LittleJerry (talk) 22:53, 11 November 2013 (UTC)
Teeth and jaws
hi, i split teeth and jaws in 2 trying to keep each part about or jaw or teeth, maybe the images in this section are not on the right place, they are about types of and not about jaw or teeth. Cheers Mion (talk) 16:13, 4 November 2013 (UTC)
I have a pretty big screen and see 3 noses, no teeth in close up, that picture could go anywhere in the article. Mion (talk) 04:10, 5 November 2013 (UTC)
Strictly speaking, the green is the dentary bone. "Mandible" refers to the entire lower jaw, whether it's composed of the dentary alone (as in mammals) or the dentary and other bones such as the splenial and angular (as in all non-mammalian vertebrates). But only the dentary ever bears teeth in the lower jaw. HCA (talk) 21:29, 5 November 2013 (UTC)
We could have "Human relations" but that sounds a bit Frankenstein. Perhaps better to have "Interactions with humans" and "Conservation" as separate sections. Cwmhiraeth (talk) 10:08, 12 November 2013 (UTC)
It looks like this article was first written in British English, but was anonymously changed in 2007 into American. WP:ENGVAR prohibits this and the article should therefore change back to its original dialect, unless there is a good argument for it being in US. Is there? John (talk) 20:48, 14 November 2013 (UTC)
This is clearly a very strong candidate. I am attempting a thorough copy-edit, since most of the article's shortcomings appear to be very minor grammar and wording issues that are very easy for me to fix. I will bring more significant issues here, along with any questions I have. Due to the thoroughness and scope of this article, it may take up to a week for me to completely review. – Quadell(talk)15:17, 20 November 2013 (UTC)
Question: I notice that the article is not consistent in the use of the serial comma. (That's not a GA requirement, but I assume you'll want to nominate this at FAC eventually.) Would you prefer to use, or to omit, the serial comma? I can fix it where I see it, if I know your preference.
Question: In the first paragraph of the "Locomotion" section, I'm confused about something. Read the part that begins "Their ankle joints flex in a different way..." and continues until the end of that paragraph. Does that describe just the "high walk"? Or is that section true for both the "high walk" and the "low walk"?
Well, its the way the joint articulates. It is of particular relevance to the high walk, which is a gait not found in other modern reptiles, but accommodates other forms of locomotion as well. Cwmhiraeth (talk) 07:07, 21 November 2013 (UTC)
Okay, great. If it were only relevant to a discussion of the high walk, I would have recommended some rearrangements to the section. But as it is, I don't think any change is needed. – Quadell(talk)13:04, 21 November 2013 (UTC)
Question/Issue: When the text says "The powerful closing muscles are low-slung", what does that mean? Is there an article this could link to explain "low-slung"? Or could it be reworded to make the meaning clear?
Question/Issue: The word "knobbly" sounds unencyclopedic to me, but I'm an American. In British English, is "knobbly" a word you might use in a semi-professional work like a Wikipedia article? If so, that's fine, but if not, it should be replaced.
Issue: Consider this passage. "Various functions for these have been suggested. They may play a part in communication between crocodilians, and also seem to produce pheromones and play a part in courtship." The three possibilities are related. If they produce pheromones, or if they play a part in courtship, then they certainly play a part in communication between crocodilians, right? Unless I'm not understanding the various theories, it should be reworded to make clear that they might have a communicative function, in that they produce pheromes and/or play a role in courtship.
Issue: "During breathing, the lungs are stretched and pushed against like a piston." Pushed against what?
Fixed.
Well no, now the article says "During breathing, the lungs are stretched and like a piston", which isn't right. The source does not mention pistons at all, so perhaps it would be best to simply omit the entire sentence? – Quadell(talk)00:17, 22 November 2013 (UTC)
Issue: "Crocodilians can hold their breath for four to fifteen minutes and perhaps as long as two hours." That's unclear, and isn't a good representation of the info at the source, which is "Usually they can hold their breath from 4 - 15 minutes but can remain underwater for 2 hours if needed and if they aren't stressed." How about something like this? "Crocodilians typically remain underwater for short periods of fifteen minutes or less, but some can hold their breaths for up to two hours under ideal conditions."
Issue: "Gaping with the mouth open can provide cooling by evaporation from the mouth lining." That's redundant, since you can't gape with the mouth closed. But I think simply saying "Gaping can provide..." might be confusing, so I would prefer a wording like "Gaping (resting with the mouth open) can provide", since gaping is mentioned in the next section, so long as the word "resting" is accurate. (I assume they are resting and not swimming or walking while they gape to cool off.)
Question/Issue: In most of the article, it is clear when you are referring to all crocodilians, and when you are referring to a single species or group. But there are some parts where I'm not sure. Notably, the "Reproduction and parenting" section begins by discussing all crocodilians, but begins discussing American alligators in sentence four. Then, in the four sentences between "Copulation typically occurs in the water..." and "...during which time the pair continuously submerge and surface", I'm not sure if you're referring to American alligators specifically, or all crocodilians. It's especially confusing because the source is a book called Crocodile: Evolution's greatest survivor. So my questions are (a), does that source really cover everything in the paragraph up to the first citation, including the bits about American alligators? And (b), do the sections regarding copulation refer only to American alligators, or to all crocodilians, or to crocodiles specifically?
Question: Related to the above, when the text says "The incubation period is two to three months", is that true for all crocodilians?
Fixed, per above.
Question: Similarly, the "Communication" section begins "The social life of a crocodile begins..." Should that be "crocodilian", or does this refer only to crocodiles?
Fixed.
Issue: Citation #59 is "Ross, p. 109", but page 109 should be a section written by Lang. Should this be Lang, or is the page number wrong? Other citations have the same problem.
That's fine for GA. If you decide to submit it as a FAC, though, you may want to format the references to be more explicit about the author. – Quadell(talk)22:34, 22 November 2013 (UTC)
The Ross references are mine. I propose get the book out from the library again (on Monday) and will check page numbers and change these citations to reflect the authors' names for the different sections. Cwmhiraeth (talk) 06:27, 23 November 2013 (UTC)
Suggestion: In the first paragraph of the "Communication" section, everything down to "Nearby adults respond quickly to juvenile distress calls" seems relevant and important. But the rest of the paragraph, from "as was demonstrated at a Papua New Guinea crocodile farm" until "making deep calls and engaging in headslapping", seems like an amusing anecdote that was only observed once. It doesn't seem important enough to be in an article about crocodilians in general. In my opinion it would be better to remove that entire section, and merge paragraph one with paragraph two.
Issue: The "Growth and mortality" section states "Birds of prey take their toll, and there are usually some malformed individuals that are unlikely to survive." Usually some malformed individuals... in each brood? Each season? Or what?
Issue: CITES (Convention on International Trade in Endangered Species of Fauna and Flora) should be linked at the first mention, in the "Farming and ranching" section. I'll leave it up to you, whether to also link at the second mention; I could make a good argument either way.
Question/Issue: There seems to be a contradiction. In the Farming and ranching section, the difference between the two is explained: "Farming involves breeding and rearing captive stock on a self-contained basis, whereas ranching means the use of eggs, juveniles, or adults taken each year from the wild." But the Conservation section claims "In the late 1970s, crocodiles began to be farmed in different countries, starting with eggs taken from the wild." Is that truly a contradiction, or am I misunderstanding?
Every farmed animal came from a wild egg if you go far enough back in its ancestry, which is what 'starting from...' means, so there's no contradiction. Said "starting off" and added a note as well (belt and braces). Chiswick Chap (talk) 19:32, 25 November 2013 (UTC)
True, that makes sense. But to be honest, the footnote feels a little gimmicky to me. In my opinion, a simple "started from eggs taken from the wild" would be ideal. – Quadell(talk)19:57, 25 November 2013 (UTC)
Suggestion: The 2nd paragraph of Conservation, about gharials, begins by describing the drastic, widespread decline of gharials over many decades. But it ends with two sentences about just "several" dead gharials in a single river in a single month, without a clear cause of death. This seems trivial, compared with the rest of the paragraph (or really, the rest of the article). We don't want to include each find of dead crocodilians in history in a general article like this. I would favor omitting those two sentences, or perhaps replacing them with something briefer and more general, such as "The gharial population continues to be threatened by environmental hazards such as heavy metals and protozoan parasites".
Issue: "This long-term decline had a number of causes, including hunting, egg collection, killing for indigenous medicine, and killing by fishermen." It seems to me that "killing for indigenous medicine" and "killing by fishermen" are included in "hunting".
Question/Issue: I'm not sure it's correct to say "In Ancient Egyptian religion, the crocodile represents Sobek... and Ammit". I don't have access to the source, and if the source says the animal represents the two gods, then that's fine. But it's usually said that the god is represented in the form of the animal, not that the animal itself represents a god.
Issue: I know what you mean when you say "Similar tales exist in Native American and African American folklore, with an alligator and Br'er Rabbit." But no Native American group told tales of Br'er Rabbit.
Suggestion: It seems to me that the tale of the Leviathan in Job would fit better in the "In mythology and folklore" section, rather than the "In literature" section. (It's both, of course.)
Comment: I altered the sentence on Herodotus. Herodotus' writings about the crocodile are found at chapter 68 of book 2, and I'm not sure the best way to summarize his description. It's possible the sentence could be further improved. – Quadell(talk)14:47, 26 November 2013 (UTC)
Issue: WP:MOSQUOTE says "As much as possible, avoid linking from within quotes". I'm not sure why "that country" would link to Prester John anyway, but "Ind" should be clarified in square brackets, like "...and by all Ind [India] be..." – Quadell(talk)14:47, 26 November 2013 (UTC)
Suggestion: The first half of the "In literature" section (besides the sentence about Job) describes the quasi-fanciful accounts by ancient historians. An introductory sentence would help the reader understand what is being described, as in "Ancient historians have described crocodilians from the earliest historical records, though often their descriptions contain as much legend as fact." (This would be easier if the Job reference were moved, of course.) Similarly, the second half is all about children's literature, so an introductory sentence would be helpful there too: "Crocodilians, especially the crocodile, have been recurring characters in stories for children throughout the modern era" (or words to that effect).
I agree. Although Job is clearly literature, it doesn't fit in well with either the ancient historians or the modern children's tales. And speculation that the crocodile inspired the Leviathan fits much better near speculation that the crocodile inspired descriptions of dragons, not to mention stories of sea monsters and interactions between crocodilians and the gods. I have moved it. I hope this is acceptable to all. – Quadell(talk)16:59, 26 November 2013 (UTC)
Suggestion: I really like Roald Dahl, but I don't think his 46-page children's story deserves more space than J.M. Barrie, Lewis Carroll, Rudyard Kipling, Shakespeare, or Herodotus. (It's always hard to keep an "In literature" or "In popular culture" section from becoming a list of whatever media the most recent editor is most fond of.)
I can't find any more needed improvements. In every section, I asked myself, is anything missing? Is there more on this aspect that should be discussed? And every time, the content seems full and complete. This article clearly passes all the GA criteria, and is probably ready for FAC if that's the direction you want to take it. Congratulations to you, LittleJerry, as well as to everyone else who participated in this nomination. – Quadell(talk)21:20, 26 November 2013 (UTC)