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Archive 1Archive 2Archive 3

Latest Research

Origin of the white shark Carcharodon (Lamniformes: Lamnidae) based on recalibration of the Upper Neogene Pisco Formation of Peru, DANA J. EHRET,*, BRUCE J. MACFADDEN, DOUGLAS S. JONES, THOMAS J. DEVRIES, DAVID A. FOSTER, RODOLFO SALAS-GISMONDI, Paleontology, Volume 55, Issue 6, pages 1139–1153, November 2012 http://onlinelibrary.wiley.com/doi/10.1111/j.1475-4983.2012.01201.x/abstract — Preceding unsigned comment added by 204.154.136.254 (talk) 17:28, 14 November 2012 (UTC)

http://www.elasmo-research.org/education/evolution/megalodon_as_sandtiger.htm Metamorphosed Fossil (talk) 14:43, 3 September 2011 (UTC)

Info-bar

In the information-bar, it lists the genus as carcharodon. Is this a reflection of Agassiz's classification, or should it be changed to carcharocles; the more accepted genus?--THobern 11:14, 24 January 2009 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)

Fixed! --Spotty11222 (talk) 00:56, 7 February 2009 (UTC)

Complete skeleton ?

complete skeleton of megalodon has never been found, only its teeth, so its impossible to estimate its size Metamorphosed Fossil (talk) 09:26, 17 October 2010 (UTC)

Some associated skeletal remains of C. megalodon have been found to date. They have revealed a great deal about C. megalodon's anatomy. Furthermore, a well-preseved specimen of C. megalodon have been found in Peru but details are expected to be revealed in future. This specimen may ultimately resolve ongoing debates concerning anatomy of C. megalodon.--LeGenD (talk) 03:05, 02 May 2010 (UTC)
can you specify which associated skeletal remains of megalodon have been found to date ?. Metamorphosed Fossil (talk) 14:04, 3 September 2011 (UTC)


i hope you know that sharks are cartilaginous and not bony fish and therfore do not fossilize at all Metamorphosed Fossil (talk) 16:22, 13 May 2011 (UTC)

On the contrary: there have been several cases where whole sharks have been fossilized, particularly in the Solnhofen, Bear Gulch and Monte Bolca lagerstatten.--Mr Fink (talk) 17:17, 13 May 2011 (UTC)
the thing you have mentioned above are not 'bones' of the shark which have been fossilized, but casts or moulds of the shark, if you have studied geology or paleontology you would have known this, its impossible for cartilage to fossilize, again if you have studied biology ? Metamorphosed Fossil (talk) 11:21, 3 September 2011 (UTC)
Yes, I've studied biology, and I have seen several intact shark fossils and whole fossils of cartilaginous fishes, pictures of which are readily available to see even in the WikiCommons. It is possible for a cartilaginous fish to be fossilized in its entirety if it is buried before it decays, like here, for example--Mr Fink (talk) 04:16, 11 September 2011 (UTC)

the only fossil remains of any shark for that matter are mostly its teeth only, and some few scattered vertebra and that is all.Metamorphosed Fossil (talk) 10:35, 3 September 2011 (UTC)

If you're not even going to make even a quarter-assed effort to bother googling the Lagerstatten I've mentioned that have fossils of whole cartilaginous fishes, please don't get surprised or upset if people don't mistake your own opinions for facts.--Mr Fink (talk) 04:16, 11 September 2011 (UTC)

Not a single complete Fossil evidence

http://www.sciencedaily.com/releases/2009/03/090312174733.htm Please read and see what you all think. Enlil Ninlil (talk) 00:29, 16 March 2009 (UTC)

yes sharks are cartilaginous and therefore do not fossilize at all, the reason why their teeth fossilize is because its covered in enamel Metamorphosed Fossil (talk) 10:38, 3 September 2011 (UTC)

Yes, that's why I've seen complete fossilized skeletons of sharks on display in museums myself. It's also why vertebrae of megalodons, not just the teeth have been discovered. — Preceding unsigned comment added by 74.214.60.223 (talk) 07:25, 2 February 2013 (UTC)
They do fossilise, just not very well. Even jellyfish are known from fossils. FunkMonk (talk) 07:36, 2 February 2013 (UTC)

Size Section

I know very little about this shark and shark research, so bare with me. I have some problems with this passage,

Shark researcher Cliff Jeremiah also has suggested a method to determine the size of the large sharks, including C. megalodon,[1] and his method is considered to be among the most reliable.[1] He suggested that the jaw perimeter of a shark is directly proportional to its total length, with the width of the roots of the largest teeth being a proxy for estimating jaw perimeter. For every centimeter of root width of the largest tooth, he asserts, there was approximately 4.5 feet of the shark. He concluded that C. megalodon could grow up to 18.2 metres (60 ft),[1] with a body mass of about 70 metric tons (77 short tons). Many scientists acknowledge this conclusion.[1][12] [13]

Based on what I have briefly read of Megalodon, Hunting the Hunter it seems like a popular book. Has any of this book been discussed or critiqued in a published journal by other researchers? I have searched google scholar for 'Jeremiah megalodon' and the only hit is this book and possibly Incremental growth and diagenesis of skeletal parts of the lamnoid shark Otodus but I don't have access to it. Is this book considered a reliable source to shark researchers?

The book Megalodon: Hunting the Hunter has been written by a paleontologist, Mark Renz in 2002. It covers most aspects of the Megalodon very nicely and also contains opinions and research works of many other paleontologist and scientists. Dr. Cliff Jeremiah is also a shark expert and his research works have never been disputed by his peers. If you want to know more about him than consult a book called Florida's Fossils by Robin C. Brown. And as far as the reliability of the book Megalodon: Hunting the Hunter is considered, it is evident from this report, that this book is a peer reviewed source. The peer reviewed sources are mentioned in pages 13 - 16).
LeGenD (talk) 09:51, 01 April 2009 (UTC)

..his method is considered to be among the most reliable. I have searched via google books for the word reliable and there are no hits in this book. I have read various passages and I have found only one comment so far as to how reliable the estimate is. There is a line in the book were a guy called David Ward apparently said This is a sound principle that works well with most sharks. Is this persons opinion the basis for this line. Based on a google search he does seem like a shark researcher, but is this one opinon anough to justifly that line which implies a consensus in the feild. That said I don't have full access to the book. And like above, google scholar says nothing about this estimate.

When a research work of an expert is not disputed and his accepted by other experts, than it is considered to be reliable. It is widely believed that Megalodon could reach or exceed 60 feet in length. You need to do more research. To name a few experts, Mark Renz, Steven A. Alter, David Ward, Stephen Wroe, George Blasing, and Dr. Bretton Kent, all agree that Megalodon could reach 60 feet. If you can contact these experts, than please do so.
LeGenD (talk) 09:51, 01 April 2009 (UTC)

Many scientists acknowledge this conclusion. Does three cites equal most? One of them is the above book that reports the estimate, the second article I only have access to the beggining part and it says 17 metres or more and the third article just says 60 feet. The last two as far as I'm aware don't acknowledge Jeremiah or were the estimate came from. I don't have access to the full article but does the New Scientist article say in it 'many scientists acknowledge this estimate by Jeremiah or is the author of the article, James Riordon, being considered as a 'scientist'? Is Steven A. Alter, the author of the third article, actually a shark researcher or a fossil collector/seller? I stress I know very little about this field. I have no problem with the size estimate being in the article but the above paragraph seems potentially misleading to me. It implies that 60ft is the most widely accepted, reliable estimate. Is it? If it is then why aren’t proper peer reviewed articles cited? Steveoc 86 (talk) 01:40, 16 March 2009 (UTC)

By the sentence "many scientists acknowledge this conclusion," it is mean't that most experts agree that Megalodon could reach 60 feet in length. I have quoted some names above. Now of-course, Dr. Cliff Jeremiah's method even confirms this, so there is some credibility in the 60 feet estimate. James Riordon is an editor of Hell's teeth article. His opinions are not his personal ones but based on what is widely believed to be true and Hell's teeth is a publication mainly based on research works of Dr. Bretton Kent on Megalodon's hunting and predation strategies. However, Steven A. Alter is a paleontologist. And of-course! The book "Megalodon: Hunting the Hunter" is a cited as a source in this case. Three of the peers of Dr. Cliff Jeremiah; David Ward, Steven A. Alter and Mark Renz from just the book already agree with the conclusion that Megalodon could reach 60 feet in length.
LeGenD (talk) 09:51, 01 April 2009 (UTC)
Thanks for the clarifications.
It's not that I have a problem the estimate or a 18m shark it's just that wiki needs reliable sources. What the article strongly implies is that this one estimate is the best and yet. Also has Mark Renz publish anything other than the Meg book? What puts me of the book is that it don't reference it sources properly and says things like Liopleurodon could reach 25m (as in, Thats what Walking with Dinosuars said, but an estimate that high has never appeared in published lit.). I don't have access to the full book. I don't have assess to pages 14-15. But what you linked to only mentioned 'Webb, S.D. 2002. 'Foreword' in M. Renz. Megalodon: Hunting the Hunter.'
The 60 ft estimate is widely accepted. It is evident from documentaries, journals, and even books written on Megalodon by various paleontologists. If all these sources are not acceptable than I don't know what is?
Mark Renz himself is a paleontologist. He has written two more books: Giants in the Storm and Fossilizing in FLorida: A Guide for diggers and divers. Here is a link which confirms this. The book Megalodon: Hunting the Hunter is a peer reviewed scientific publication. (Its name is mentioned in the list in the link shown above. For more details, you shall contact FLMNH.). Also, it was written in 2002 and at that time, it was widely believed that Liopleurodon could reach 25 m. Even if it doesn't, one species is known to have exceeded 20 m in length but this is a different debate. Things and opinions have changed a lot since 2002. Over-all the book contains accurate information and mostly experts have been consulted in it. If you don't have the book and than on what basis are you doubting its credibility? Experts seem to like it. (See Editorial Review section)
LeGenD (talk) 12:10, 02 April 2009 (UTC)
I have a problem with the internet link to Steven A. Alter’s article. It was apparently published in the Journal of Amateur Paleontology in 1997, if so, then that’s better. (is this it [1] is it peer reviewed?) The internet link in the does not show any references. Why not just cite the original article.
‘’And of-course! The book "Megalodon: Hunting the Hunter" is a cited as a source in this case’’ How can a 1997 article use the 2002 Meg book as a reference? !? Maybe I need to research time travel.
regarding the ‘’Hells Teeth’’ article: even if based on decent sources James Riordon shouldn't be used as a scientist he's a journalist.
The link will be moved from that section.
LeGenD (talk) 12:10, 02 April 2009 (UTC)
Who is George Blasing?!? You mean the Jurassic Fight Club guy. Did you throw in him as a joke? How, on this earth, is he a credible expert. Did you watch JFC! (Please for the love of all things good and pure, don't put JFC as a reference.  ;) ) Steveoc 86 (talk) 09:39, 1 April 2009 (UTC)
Who is George Blasing? He is a paleontologist. He has lot of experience in this field. Here is his website. He wasn't the only one to give advices on extinct animals in Jurassic Fight Club, though he played a major role. His works are over-all well recieved. If you doubt his credibility than keep in mind that what a paleontologist, Jack Horner, did in case of T-Rex in the Jurassic Park movies. He surely deserves the top spot in stupidity level.
LeGenD (talk) 12:10, 02 April 2009 (UTC)
Thanks for taking the time to discuss this, the current version is looking much better! Again I stress, If the majority view is that Meg could reach 60ft then that's fine with me. I'm not trying to change that. I don't have anough knowledge of this animal to do that. However if this is true and like you say It is evident from documentaries, journals, and even books written on Megalodon by various paleontologists, were are the many references? It may be evident to you but think about the poeple reading the article. It might not be that evident to them. The book is fine as one of the sources, (Although I'd prefer more peer reviewed sources) the only thing I won't accept is jurnalists and documentries.
((jurnalists usually arn't experts. If an expert is staiting an opinion in a documentry then that is more acceptable. Seriously the narrators of documenties often talk rubbish. I quote 'We now know that Megalodon was so massive it could eat a T.rex!!' The narrator in JFC says it could grow 50 ft or more, but it then says, thats the size of a jumbo jet!! That's why I don't like documentries as refernces.))

Anyway thanks for your time. Steveoc 86 (talk) 11:26, 2 April 2009 (UTC)

I can understand your concerns. More references will be added soon. In the shows like JFC, some comments are mean't for publicity purposes and entertainment, so they shouldn't be taken too seriously. That's how such shows work. The point is that not all journals and documentaries are bad. Many among them are good and accurate in most accounts. The Hell's teeth is a very reliable and informative journal. It is based on research works of Dr. Brentton Kent on Megalodon's hunting tactics. I have full access to most of these classified sources, so I know better. I will fix the entire article very soon as its status is under reassessment.
LeGenD (talk) 10:35, 03 April 2009 (UTC)

GA Reassessment

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

The reason for reassessment is inaccuracy regarding one possible cause of extinctions, linked to the extinction of basilosaurus: the later is believed to have become extinct 34 million years ago while megalodon's oldest remains are about 18 million years.

No where it is mentioned in the article that the extinction of the Basilosaurus has any linkage with that of the C. megalodon. It is just a reference example that factors such as "Climatic Upheavels" and "Shortage of Food" can cause demise of any marine species. Basilosaurus also went extinct due to similar reasons and of-course it happened much earlier. However, if some one feels that the reference is invalid and shall be removed than I have no issues with it. LeGenD (talk) 10:51, 31 March 2009 (UTC)
I have removed the controversial information from the main article. LeGenD (talk) 1:46, 31 March 2009 (UTC)

Comments from Philcha

I've done a few GA reviews and written a few GAs, both including zoology and paleontology topics. I would not pass Megalodon as a GA in its current state, but think the faults can be fixed by a determined editor within 2 weeks:

  • A lot of the writing is clumsy, sometimes bordering on ungrammatical, e.g. (only a limited sample, there are more):
    • "Due to notable similarities among the teeth of the great white shark, Carcharodon carcharias and megalodon, Agassiz proposed the genus, Carcharodon for megalodon" (section "Taxonomy").
    • "There is a major disagreement among scientists as to how C. megalodon should be classified.[1][2] The controversy is that whether C. megalodon is a close relative of the extant great white shark or whether the two species are distant relatives" could be condensed into one sentence.
    • In "According to Carcharocles proponents, Otodus obliquus evolved in to Carcharocles aksuaticus,[1][6] which evolved in to Carcharocles auriculatus,[1][6] which evolved into Carcharocles augustidens,[1][6] which evolved into Carcharocles chubutensis,[1][6] which eventually evolved into megalodon"
      • IMO should say e.g. "According supporters of classification as Carcharocles" --Philcha (talk) 13:47, 1 April 2009 (UTC)
      • The multiple use of "evolved into" suggests a chronospecies. Is that what the sources are describing? If so, the article should say it explicitly. This seems to be what Ward proposed, but I don't know how widely it's accepted in the Carcharocles faction. If not, then e.g. "megalodon evolved from Otodus obliquus via ..." would leave open the possibility that the other species produced other descendant species and that there may have been chronological overlaps in the sequence. In fact I think it's prudent to do that anyway, and treat the chronospecies question as a separate issue. --Philcha (talk) 13:47, 1 April 2009 (UTC)
    • "Carcharocles proponents also point out that the great white shark is more closely related to an ancient shark Isurus hastalis, the "broad tooth mako", than C. megalodon" is ambiguous - is I. hastalis more closely related to megalodon or the the Great White? --Philcha (talk) 13:47, 1 April 2009 (UTC)
    • "Based on the study of the 4 million years old fossilized remains, the most complete yet found, of head elements of an ancient form of great white shark (discovered in Peru in 1988, and donated to the Florida Museum of Natural History in 2008)" is a longish sentence without a verb. --Philcha (talk) 13:47, 1 April 2009 (UTC)
    • Needs to explain or work round tech terms, e.g. "centra" in "Anatomy and appearance", "dental formula" and related terms such as "mesial" in "Jaw dentition". --Philcha (talk) 13:47, 1 April 2009 (UTC)
    • Needs to avoid WP:PEACOCK terms like "super predator" (in "Anatomy and appearance") and "colossal bite force" (in "Behavior"). In the case of bite force, comparisons with e.g. the Great White, Dunkleosteus & other large predatory ifish, a large croc, T rex and possibly Liopleurodon (if not grossly exaggerated by Walking with Dinosaurs) would be more informative and perhaps more impressive, e.g. if it had even half T rex' bite force megalodon would have been death at first bite if it got a solid hit. --Philcha (talk) 13:47, 1 April 2009 (UTC)
    • The final para of "Extinction" looks like a repetition of the bullet list(s). --Philcha (talk) 13:47, 1 April 2009 (UTC)
      • I think that's enough about the prose for now.
  • A few of the sources are 2nd-rate, e.g. In Gedenken an Vito Bertucci. I'm quite flexible about this in non-academic subjects (IMO WP:RS has an academic and corporatist bias that causes difficulties in non-academic subjects), but this is a science article and there's little excuse for not using academic sources, or at least more "popular" articles by recognised experts or published by research / academic organisations like WHOI or UCMP.
  • That suggests to me that a thorough check of all the refs is needed. --Philcha (talk) 12:47, 9 April 2009 (UTC)

Hi, LeGenD, I see you're doing some serious work here. Pl leave a message here or at my Talk page when you think it's time for me to do a more detailed review. --Philcha (talk) 12:49, 11 April 2009 (UTC)

Philcha, Thank you for your patience. I have been going through some sources used in the main article to see if any errors still persist in the content of the main article or if more information could be added. Some content needs further improvement. I am up for the task and will correct such issues within this week. Once I am done, I will leave a message here for you. --LeGenD (talk) 09:51, 27 April 2009 (UTC)
Philcha, You shall conduct a more detailed review of the entire article and suggest more improvements, if necessary. It will make it easy for me to fix issues, if any still persist. Thank you! --LeGenD (talk) 11:58, 05 May 2009 (UTC)
I wish it was that simple. I got curious about how this article passed a GA review in the first place, and did some detective work:
The bottom line is that I think the original GA pass was invalid, and will ask someone more familiar with the mechanics to undo it (under the covers there are several pages, lists and categories that need to be kept consistent).
However I appreciate the work you've been putting into this, and will produce more detailed comments after I've tried to sort out the mess. My comments will not be as detailed as a full GA review, since I only got into this because Talk:Megalodon is on my watchlist following some comments I posted a while ago, and I'm busy with a complex article and a long, complex GA review.
If you disagree with my conclusion that Megalodon should never have been a GA, I suggest you raise the issue at WT:GAN - the most liekly result of this would be another reassessment. --Philcha (talk) 10:14, 5 May 2009 (UTC)
I've now raised the "invalid pass" issue at Wikipedia_talk:GAN#Megalodon_passed_as_GA_improperly.3F. I'm adding more detailed comments below.

Coverage

The article covers all the topics I'd expect an article about a fossil genus or species, and all the points that I was aware of from previous casual reading. I have not surveyed the scientifc literature to see if there are any other major issues that need to be covered, but I'm fairly confident that the article meets the GA criteria's requirement for "broad" coverage. --Philcha (talk) 10:43, 5 May 2009 (UTC)

Structure

In my opinion the structure is almost completely backwards. I think it makes much more sense to start with the evidence (the fossils) or perhaps the history of discovery, and that classification should be last, as it depends on the fossil evidence and on conclusion drawn from that evidence, e.g. reconstructions. For examples see Kimberella and Opabinia. So I'd go for the order: history of discovery; description of the fossils, including the time range ; reconstruction; lifestyle, behaviour & ecology; extinction (in this case the hypotheses depend on views of its ecological role, prey & hunting behaviour); classification. Since fixing this will very probably involve major changes, the rest of my comments are provisional and detailed review of the (new) sections will have to wait until the structure issue is resolved. --Philcha (talk) 11:13, 5 May 2009 (UTC)

Sources

  • Too many of the sources look like "some guy's web page". For scientific aspects of articles web pages are only usable if you can showe that they were created by an authority in the field (e.g. Ctenophore cites pages by Claudia E. Mills, but also at least 1 scientific journal article that she co-authored), or are published by a university or other reputable research organisation and are not the work of students (Mill's pages are hosted by a university, and if you root around that site you'll see that she's on the academic staff, not a student; in other articles I've used web pages from UCMP, the University of California Museum of Paleontology, which I notice Megalodon also uses). Scientific journal articles are the best sources, followed by books by people who've also published scientific journal articles, provided neither their articles not their books have been shown to be unreliable by other authorities in the field. --Philcha (talk) 11:13, 5 May 2009 (UTC)
  • The most widely used source is Mark Renz' book Megalodon: Hunting the Hunter. Renz is an experienced fossil finder and guide with a specific interest in sharks, but that does not prove that he's an expert on the analysis and classification of fossils. That does not mean he's not an expert, for example Gregory S. Paul started as an illustrator specialising in dinosaurs but his desire to reconstruct dinos accurately got him deeper and deeper into the science, and he's now well respected by scientists and has got articles published in scientific journals. That's the sort of thing you'd have to demostrate for Renz in order to use him as an authority. Even then it would be safer to widen the range of sources, to avoid concerns that Megalodon might be promoting one person's point of view by giving undue weight to his writings. --Philcha (talk)

Classification dispute

  • The whole section appears to be "he said ..., she said ...", like a kids' quarrel. You need to explain the reasons for the different views. That's a major reason why I suggested a different structure, because in that structure the article would already have explained the features found in the fossils. --Philcha (talk) 12:49, 5 May 2009 (UTC)
  • By showing only 1 cladogram you're supporting one point of view, which WP policy forbids. If there's a serious controversy you should give about equal prominence to at least the two most widely-cited views, which mneans that if you illustrate one with a cladogram you must do the same for the other, as at e.g. Evolutionary_history_of_life#Flowering_plants. --Philcha (talk) 12:49, 5 May 2009 (UTC)

Megalodon within Carcharocles

  • If the megalodon lineage was a chronospecies, by definition it can't be a family tree as it has no branches. --Philcha (talk) 12:49, 5 May 2009 (UTC)
  • "his stunning revelation has received recognition from several shark researchers (e.g. J. Bourdon, L. Andrez, H. Capetta, V. I. Zhelezko, and V. A. Kozlov)" has 2 problems:
  • "his suggestion is given credence by many scientists due to some convincing evidence" is redundant (it cites 2 of the 3 sources cited by the next sentence) and looks like rhetoric. --Philcha (talk) 12:49, 5 May 2009 (UTC)
  • As it stands "One reason is that the teeth of I. hastalis and C. carcharias are remarkably similar in shape, differing only in that the former lack the characteristic serrations of the latter" is unconvincing, since teeth often convergently take similar forms in widely separated lineages - for example sabre-teeth have evolved several times, from Permian theriodonts to various Cenozoic carnivores, including the marsupial Thylacosmilus as well as the placental Smilodon; skulls and teeth of marsupial and placental carnivores often show conbergent evolution, e.g. the skull, jaws and teeth of the marsupial thylacine are very simliar to those of large canids such as wolves. --Philcha (talk) 12:49, 5 May 2009 (UTC)

Anatomy and appearance

  • I was surprised to see that jaws are not included among the fossils, as vertebrate predators' jaws are usually pretty stong. Then I found what shark says about how shark jaws are strengthened without the use of bone. I think an explanation is needed of why shark jaws are less good candidates for fossilisation than one might expect. --Philcha (talk) 12:49, 5 May 2009 (UTC)

Size estimation

Jaw dentition

Recent findings from japan (almost complete natural set) shows that megalodon dental formula doesn't include intermediate tooth at the upper jaws, so the correct formula for upper jaw on this species is 3.0.7.4, that discovery directly links megalodon to the otodus lineage, putting on the Carcharocles genus. — Preceding unsigned comment added by Oxy75 (talk • contribs) 09:47, 2 September 2013 (UTC)

  • I'm not sure what this section contributes to the article. The only point at which it touches on a major aspect of the article is "However, in the case of the great white shark, the intermediate tooth does points mesially. This point has often been raised in the Carcharodon vs. Carcharocles debate regarding the megalodon and favors the case of Carcharocles proponents" --Philcha (talk) 12:49, 5 May 2009 (UTC)
  • What is an "artificial dental formula"? It could mean "pure guesswork" for all I know. I see the term is used without explanation in the web page cited, and specialists may understand the term, but WP is not written for specialists. --Philcha (talk) 12:49, 5 May 2009 (UTC)

Skeletal reconstruction

Distribution, range and habitat

  • Citation needed for "The oceans were noticeably warmer during the Miocene and early Pliocene. This would have made it possible for this species to flourish around the world". --Philcha (talk) 12:49, 5 May 2009 (UTC)

Comments from Philcha (version 2, after major revision of article)

Start of review

Since there have been major revisions, I'll approach this as a new GA nomination. The rules for GA reviews are stated at Good Article criteria. I usually do reviews in the order: coverage; structure; detailed walk-through of sections (refs, prose, other details); images (after the text content is stable); lead (ditto). Feel free to respond to my comments under each one, and please sign each response, so that it's clear who said what.

When an issue is resolved, I'll mark it with  Done. If I think an issue remains unresolved after responses / changes by the editor(s), I'll mark it  Not done. Occasionally I decide one of my comments is off-target, and strike it out

BTW I've occasionally had edit conflicts in review pages, and to reduce this risk I'd be grateful if you'd let me know when you're most active, so I can avoid these times. --Philcha (talk) 17:59, 25 September 2009 (UTC)

Coverage

Structure

(to be done when any issues in the main text have been resolved) link checker

(to be done when any issues in the main text have been resolved)

Use of images

(to be done when any issues in the main text have been resolved)

Lead

(to be done when any issues in the main text have been resolved)


- - - - - please add review comments /responses above this line - - - - -
 If you want to start a new section of the Talk page while this review is still here, edit the whole page, i.e.use the "edit" link at the top of the page.

Removal of picture

There have been attempts to insert a picture of a low quality tooth. The picture is taken at an odd angle and is completely redundant considering that there is a picture of a better quality tooth right above it. The other picture above is also better angled - pictures should be clear and not dramatically angled - and has a better scale. There seems to be no good reason to fill the article with inappropriate pictures of low-quality teeth.---THobern 02:37, 8 August 2009 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)

Please don't reinsert the picture without discussion.--THobern 02:40, 8 August 2009 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)
Agreed. The image seems to be redundant. mgiganteus1 (talk) 03:18, 8 August 2009 (UTC)

I suggest to use a picture showing a megalodon tooth in a more common color--dark gray or black. Meg tooth like the one in the current photograph(light tan in color)is just a small proportion.VicLin (talk) 10:03, 22 September 2009 (UTC)VicLin

The one in the article has the best quality of the images we have on Commons. Darker teeth can be seen in the taxobox image, I believe the AMNH jaws have real teeth in them. FunkMonk (talk) 10:15, 22 September 2009 (UTC)

Steven Alter's article as a source

Steve's article is not a reliable source; it is an article for an amateur paleontological newsletter, and is hosted on a commercial site. Furthermore, it is incorrectly used to support the claim that 59' is a widely accepted length; the source simply says that this is the maximum accepted length; it doesn't comment on the level of support given to this claim.--THobern 05:48, 10 August 2009 (UTC)

This citation has been removed as per your suggestion.
LeGenD (talk) 09:45, 25 September 2009 (UTC)
By me.--THobern 04:52, 29 September 2009 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)

Notes on Sources

I'm concerned about the sources here, as many are at best "popular science" and few are by recognised academics. Here are some I'd feel confident I'd be confident using, based on Google Scholar (some probably are already used) - there seems little academic literature on megalodon:

Learn to differ between claim and fact!

I have corrected several idiocies (the word is deserved, even considering WP politeness guidelines), e.g. repeated use of "shows" for "claims". Generally, the lack of thought displayed by (at least) one previous editor is worthy of high schooler---and not one particularly bright at that. 188.100.205.226 (talk) 23:27, 28 October 2009 (UTC)

Gosh. Thanks be to Allah that you've arrived now, and can sort us out. --Geronimo20 (talk) 00:04, 29 October 2009 (UTC)

Megalodon age

It has been pointed out in some sources that earliest remains of C. megalodon date back to late Oligocene epoch. Paleontologist David Ward has confirmed that he has an Oligocene age C. megalodon tooth in his possession (information from the book: Megalodon: Hunting the hunter). Some other scientists, M. D. Gottfried and R. Fordyce, have also confirmed the occurrance of C. megalodon fossils from Oligocene sediments (information from the research paper titled: An associated specimen of Carcharodon Angustidens (Chondrichthyes, Lamnidae) from the Late Oligocene of New Zealand, with comments on Carcharodon interrelationships). Some 2nd grade sources have also provided similar revelations. Hence, I believe that these confirmations should not be ignored and thus I have made relevant modifications in the article accordingly. Though, I am keeping the earliest date at 25 MYA for now, and Oligocene epoch ends at 23 MYA. However, I would appreciate some additional input in this regard.

LeGenD (talk) 09:30, 02 November 2009 (UTC)

I found a japanese research paper, which reveals that oldest known fossils of C. megalodon are around 28 MYA old (reliable records). Very interesting. LeGenD (talk) 24:46, 14 April 201 (UTC)

Megalodon tooth picture.

The picture of the tooth with the ruler is a little off; comparing the tooth in the picture against the ruler, it appears to be 17cm long. I have a larger tooth in much better condition (see the lead image in Shark tooth). I could take photos of the front and the back, with a ruler or scalebar that isn't misleadingly sloped and placed. I thought I'd check here first though, so as not to step on any toes.--THobern 02:32, 7 November 2009 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)

THobern! The image you uploaded is very impressive. If you can modify it along with a measurement scale (for checking its slant height and root width), than it will be appreciated. I am willing to accommodate new and better images for the main article.
LeGenD (talk) 08:39, 09 November 2009 (UTC)
If a new image has better quality than the old ones, sure, replace them. FunkMonk (talk) 15:44, 9 November 2009 (UTC)
I'll try to get around to taking a photo of the tooth with a ruler, but just modified another image for now. How do people feel about scale bars; a ruler in the picture, or a scale-bar graphic added in later?--THobern 05:19, 10 November 2009 (UTC)
A very decent image indeed and I think that the scale bar would do the job. However, do point out in the image that whether the scale bar represents size in inches or cms. This will end any confusion.
LeGenD (talk) 09:50, 10 November 2009 (UTC)
You haven't given the image a license tag, if you don't, the image will soon be deleted, so hurry up. FunkMonk (talk) 04:36, 11 November 2009 (UTC)
Removed the old image after it had been reinserted; it's superfluous now, and the image was problematic already, as the ruler was angled against the tooth (which was also damaged).--130.56.71.50 (talk) 01:48, 13 November 2009 (UTC)

Genus of Megalodon

People should keep in mind that scientists have yet to reach a consensus on the genus for the Megalodon and the dispute continues to date. So we cannot just out-rightly declare that it is Carcharodon megalodon or Carcharocles megalodon. Until the controversy is resolved, we need to adopt a cautious tone. The Oligocene age records of Megalodon contradict with the suggestions of "Carcharocles proponents." These findings indicate that Megalodon actually co-existed with the Carcharocles angustidens and expose the flaws in the theory proposed by the "Carcharocles proponents."

LeGenD (talk) 08:05, 08 November 2009 (UTC)

20 metres

Skimming the cited source, I couldn't find any mention of the claim that C. megalodon reached 20m. Could I get a direct quote from the book? Secondly, the part about the Bertucci reconstruction will have to go; his reconstruction is not reliable; it was an unpublished display piece.--THobern 08:05, 10 November 2009 (UTC)

For (20 m) hypothesis by Gottfried et al, check page 61 of the book Great white sharks: the biology of Carcharodon carcharias By A. Peter Klimley, David G. Ainley. This estimation was also confirmed by S. Wroe et al, in 2008, as you can see in this peer reviewed scientific publication (PDF File).
Furthermore, it also depends upon how large are the fossils used and what particular methods are applied. Normally, scientists work with what they have got. Vito Bertucci during his expeditions, excavated some of the largest Megalodon fossils we have ever seen. So these fossils do represent very large individuals. Have a look at one his finds here. This is a UA tooth and it has a maximum height of 7.37 inch and root width of 5.5 inch (also confirmed through personal communication with Mark Renz). Now if you use this tooth in the last two popular size yielding methods, we get a size of 17.7 m (through Gottfried et al regression) and 19.1 m (through Dr. Clifford Jeremiah's method). So this tooth represents a shark somewhere between 18 - 19 m in length. Than of-course, there are reports of even larger C. megalodon teeth, which would obviously represent larger individuals. Again (See "External Links" for details) in the main article.
Also, you are wrong in your assertion that Vito Bertucci's jaw reconstruction is inaccurate. Can you cite any source which confirms any inaccuracy in Vito's construction? And what issues do you yourself see in his jaw reconstruction? And I believe that this jaw reconstruction was published in a famous book on Great White Shark by Richard Ellis. This book cannot be previewed on the internet though. So if you can get access to a copy, than do check it out. Just because this guy is deceased, it does not means that we should ignore his contributions.
Only Bashford Dean's jaw reconstruction has been declared to be inaccurate and its errors can be easily spotted even in the picture.
LeGenD (talk) 09:36, 10 November 2009 (UTC)
I'm having trouble finding the 20m length estimate in Wroe et al. 2008, can you point out the page number? Dinoguy2 (talk) 17:06, 10 November 2009 (UTC)
Check the table in page 3 of the scientific publication. The Megalodon with a body mass of 103197 kg is 20 m long, while the Megalodon with a body mass of 47690 kg is 16 m long, as you can verify these statistics from the size comparison table provided in page 61 of the book.
LeGenD (talk) 10:15, 10 November 2009 (UTC)
Must be off it, I'm still only seeing body mass, no length listed? In the text directly above Table 2 it lists 6.4m for the white shark but does not appear to give length for C. megalodon. Is this possibly in the supplementary data somewhere? It mentions applying the methodology for white shark bite force to megalodon using the listed mass estimates, but these methods do not seem to involve length, or length is not given by the authors. Are you extrapolating from the mass estimates to presume they must then necessarily agree with the length estimates in the book? They do cite it so I suppose that's close enough... but still, why not just say that? You implied above that the length estimate was repeated by these authors, not that they merely cited (not tested) Gottfried's stats. Dinoguy2 (talk) 17:31, 10 November 2009 (UTC)
Actually Gottfried et al, provided a method to validate the body mass of the large white shark with respect to its length. The team provided a table and even a regression length-mass relationship diagram to validate this relationship. S. Wroe et al picked up two most popular Meg size estimates from the sources for their research. However, this team used the body mass figures in place of length estimates for the research. This approach is still in accordance with the length-mass validation figure and a table provided by Gottfried et al (See pages: 61 - 62) in book. Hence, their is no contradiction. The 103197 kg body mass indirectly implies 20 m Megalodon according to statistics by Gottfried et al.
LeGenD (talk) 11:25, 10 November 2009 (UTC)
I can only see an estimate of 15.9m at p. 61. We can't synthesise findings to draw conclusions. --THobern 01:23, 11 November 2009 (UTC)
That is because you are not paying attention. Check Table 1 in page 61 and have a look on the estimates of the largest mature female and check Figure 4 in page 62 and have a look at the size range of adult Megalodon: 10 m - 20 m. Also, check the body mass figures of Megalodon provided in the referred scientific publication by S. Wroe et al.
LeGenD (talk) 09:35, 11 November 2009 (UTC)

Picture

It seems that we have two similar images, it's obviously pointless to keep them both; which one do people prefer?--THobern 15:18, 13 November 2009 (UTC)

I've added an updated image; any thoughts now?--THobern 23:34, 26 November 2009 (UTC)
I don't see why we can't have both. The two teeth differ markedly in both shape and colouration and the images show opposite tooth surfaces. Maybe we could use template:multiple image to place them side-by-side in the article. mgiganteus1 (talk) 09:33, 27 November 2009 (UTC)


Bite Force section

leaving my oppinions surrounding the Meg's bite force aside, the section clearly says 5 times the power of T-Rex. It is of course talking about the bite force but Megalodon DOES NOT have a bite of AT LEAST 100t. Now 18t is pretty excessive for a shark but 100t!? It needs changed. Spinodontosaurus (talk) 17:52, 29 November 2009 (UTC)

Here is the study that got the 20t bite for T-Rex. http://news.softpedia.com/news/Why-T-rex-Had-the-Strongest-Ever-Bite-of-a-Land-Animal-55140.shtml T-Rex's article also needs up-dating with this. So i will post it on the Rex talk page too. Spinodontosaurus (talk) 18:09, 29 November 2009 (UTC)

Actually the reference you have quoted is not very reliable. For more details check the cited scientific publication in the main article. And Megalodon had a bite force of around 18 t, which is the highest for any species calculated to date. No where a bite force of 100 t is mentioned as you presume.
LeGenD (talk) 11:03, 03 December 2009 (UTC)

I say it didnt have a 100t bite force as that is the truth. But the main page indirectly says that (though probally by accident). And i have never heard of a T Rex bite force as low as 3.6t. I dont see the problem with the study (though the link i gave isnt the best refference i know). Spinodontosaurus (talk) 19:03, 6 December 2009 (UTC)

The giant shark Megalodon, which means "Big Tooth" in Greek, may have grown to more than 50 feet long and weighed up to 110 tons (100 metric tons), at least 30 times as heavy as the largest of its living relatives, the great white shark. - As you can see! The 100 t figure represents the body mass and not the bite force of the largest Megalodon. T-Rex's bite force or around 7000 pounds (3.6 t) was presented by Rayfield, 2004. His assertion is this: it is unlikely that all teeth would have contacted a prey item simultaneously and if force is scaled for tooth size.
LeGenD (talk) 03:39, 08 December 2009 (UTC)

I have a feeling this is the ref you ment [2]. If so i can already see its flaws. Computers may estimate a GWS bite at 2t, but that doesnt compare to real life in the field bite tests which have never yielded more than 400 pounds. But then it goes and says that the GWS bite is the strongest of any mosern animal, but 2t isnt more than a Salty's bite of 3t. Spinodontosaurus (talk) 19:15, 6 December 2009 (UTC)

Actually! Dr. Brady Barr conducted an experiment in this regard too as you can see here. The great white shark involved isn't very big and yet it demonstrated a bite force of around 670 pounds. In the first attempt, it even destroyed the equipment so it is possible that we have an under-estimate from the second attempt. Now! The largest great white sharks are known to have approached or exceeded 6 m in length. These freak individuals can exert far more powerful bite forces.
LeGenD (talk) 03:44, 08 December 2009 (UTC)

Okay but Saltys still have a stronger bite (the one that yeilded over 3t was only 4.5m long, they too can excced 6m). And what i meant by 100t is that the article says meg has a bite 5 times more powerful than a T rex. Yet Meg has an 18t bite (i belive) but Rex has been found with 20t (ill dig the link up soon). Spinodontosaurus (talk) 17:16, 8 December 2009 (UTC)

found it. Spinodontosaurus (talk) 18:04, 17 December 2009 (UTC)

shark teeth are NOT attached to their jaws: its not because of their jaws that they show a strong "bite force", but because of their very sharp teeth, which enables them to cut through Metamorphosed Fossil (talk) 09:21, 17 October 2010 (UTC)

The 20 ton (for T. Rex) estimate should be the one we use for this article. Meers's estimate for T. Rex bite is 183 kN to 235 kN, and he got that number by scaling up the bite force with weight, which is I think is how the Megalodon bite force estimates were found. (Big weight to small weight is 114 tons/65 tons, which is about  182201 newtons/108514 newtons) Estimates for all the animals listed vary a lot anyway, even that of the great white shark, so I think that we should just remove the section comparing the megaldon's bite force to the other animals'.Qwertzy (talk) 03:00, 2 February 2012 (UTC)

Increased signs of vandalism

I have noticed that some non-members of wikipedia have attempted to remove entire sections from the article (e.g. Hunting behavior and bite force sections were removed by an IP 206.226.143.4). These types of actions warrant attention from fellow wikipedians and some protection status shall be awarded to the main article. It requires lots of effort and time to make useful contributions to an article and acts like these can tarnish the hard work and should be discouraged. I have restored these sections now.

LeGenD (talk) 10:46, 03 December 2009 (UTC)


Competition

While the appearance of Orcas during Pliocene may be perceived as one of the factors behind Megalodon's demise. The reasons cited are not very convincing to many experts. Megalodon was still better at killing whales. What Orcas could achieve with pack behaviour, Megalodon could achieve single-handedly. Also, this hypothesis has been questioned in a recent documentary on Megalodon by National Geographic due to lack of convincing evidence and the observation that the great white shark persists to the present time, despite being targeted by Killer Whales. A fight with pack predators from Miocene age has been demonstrated in the documentary. Megalodon kills one individual from the pack and drags the remaining pod members to greater depths, where the pod members are forced to abandon their pursuit to avoid any potential breathing issues. This should be kept in mind: Modern whales cannot fight so well against pack predators because they aren't as well armed, are surface breathers, and also have sometimes calves to protect. So criticism (opposing views) to this hypothesis should not be ignored but pointed out in the main article.

LeGenD (talk) 08:32, 14 December 2009 (UTC)

I believe that a section is necessary which would explain as to how C. megalodon handled the competition. I have added a section titled "interspecific influence," which can serve this purpose. Some inspiration came from a scientific research paper titled: Paleoecology of fossil white sharks by Robert Purdy, in which it was pointed out that the great white sharks generally avoided regions inhabited by C. megalodon. More inspiration came from depicted struggles for dominance between C. megalodon and various pack predators during Miocene and Pliocene. By now, such encounters have been presented in two paleontological documentaries (i.e. Deep Sea Killers episode of show - Jurassic Fight Club from History Channel and Monster Shark episode of the show - Prehistoric Predators from National Geographic), so this information deserves attention.
LeGenD (talk) 11:40, 14 December 2009 (UTC)
My suggestion would be to cite books, journal articles, etc. in preference to TV documentaries whenever possible, for several reasons. The documentaries are not necessarily readily accessible to everyone. The content of the documentaries is also influenced by the need for drama and may not all have been vetted by scientists. A documentary focused on megalodon, which needs to stress how fearsome a predator it was to maximize ratings, might not be expected to be entirely objective. It's also worth noting that great whites do seem to avoid areas with orca. I am not in the least in favor of suppressing opposing views, if they are logical and suitably referenced. WolfmanSF (talk) 07:15, 24 December 2009 (UTC)
I am amazed by your over-hyping of pack predators and biased approach to usage of sources. Books and Journal Articles can be as reliable as Paleontological documentaries. Can you prove that orcas wiped out the Megalodon? No you cannot. It is just a speculation. The documentaries can actually project events in a much more realistic manner. And Paleontological docmentaries are mostly vetted by scientists. Documentary makers do consult appropriate experts of the concerned field, when making one. The documentary titled Prehistoric Predator: Megalodon from National Geographic features several reputed scientists; S. Wroe, Dr. Chuck Ciampaglio, Dr. Bretton Kent, Dr. M. D. Gottfried, Dr. Gordon Hubbell, Dr. L. G. Barnes (shark and cetacean expert) and several more. The entire documentary is based upon information provided by these scientists. Now having access to the paleontological documentaries or not, is not a valid excuse. Any person can buy the DVDs. Whether you like it or not! I will use paleontological documentaries as reference sources in the main article because Wikipedia clearly permits it. Also, scientists present C. megalodon as a candidate for being the most formidable carnivore to have ever existed (Here are actual lines: Its gigantic, whale eating relative, Carcharodon megalodon, was arguably the most formidable carnivore ever to have existed). Here is the confirmation from a published scientific research paper.
LeGenD (talk) 06:14, 27 December 2009 (UTC)
The idea of megalodon attacking a pack of sizable predatory cetaceans and dragging one down to the depths seems speculative, and doesn't make sense to me. Megalodon would not have needed to put itself at risk like this; it would have been defenseless while its mouth was full, and could not have prevented other pack members from nipping at its fins, etc. More likely, it would have confined itself to attacking cetaceans that couldn't bite back, or at least solo toothed whales that could be incapacitated with its initial strike. A further reason is that it likely relied on stealth for its attack, which is harder to attain when attacking a group. WolfmanSF (talk) 20:34, 25 December 2009 (UTC)
So what makes sense to you actually should be given priority while other views should not be? Also, I am amazed by how conveniently you avoid mentioning these prehistoric cetacean apex predators: Killer Physeterids and Squalodonts - which according to experts; lived in pods, hunted in packs, and had echolocation, just like modern age orcas do. These predators can be used to draw parrallels with orcas, who aren't the only known pack predators that we should talk about. I can also provide a published article on fossil records of orcas which may put a dent on the image of the journal article that you have cited to support the claim that prehistoric relatives of the orcas may have out-gunned the Megalodon. Want me to provide it?
You also have a very one-sided perception of the capabilities of cetacean pack predators. Sharks have remained apex predators of the seas for a very long time (> 400 million years). This feat alone is an eye-opener. The megatoothed sharks specially evolved to deal with the threat of cetaceans in the oceans and they were immensely successful as fossil records have confirmed. Many cetaceans during Neogene period lived in pods and evolved echolocation. Megalodon was a primary predator of cetacean of the time and certainly had the capabilities for the purpose. Attacks on prehistoric killer cetaceans by Megalodon have also been confirmed by fossil records recently and this discovery have been featured in several new paleontological documentaries to date. The Megalodon was a very big, vicious, formidable, and powerful predator (a unique shark by all accounts). The great white shark simply pales in comparison. The Megalodon had some key advantages over potential competitors. Mentioning them is also important.
And sharks can pull smaller animals underwater to feed upon them. It depends upon the size and strength of the shark involved. Even a great white shark can do so: seals, such as the 1.5-meter Harbor Seal (Phoca vitulina), are grabbed at the surface and pulled underwater until they stop struggling, then eaten at or near the bottom - as confirmed from here. A 50+ foot and 50+ ton predatory shark would easily drag a 5 ton animal to deeper depths at will. Use your common sense. Also, you misunderstood my point: "Megalodon would have dragged the attacking pack predators to deep waters." While doing so, Megalodon may not have an animal in its mouth. Of-course! It would concentrate its energies on defensive strategies and escaping rather than on pulling down a prey item, under such circumstances. In the paleontological show by National Geographic, the battle was depicted like this: "Megalodon saw a prehistoric killer whale lurking nearby and attacked it. The Pod members of the victim quickly joined the battle to help their wounded companion and forced the Megalodon to release their wounded companion. However, the wounded companion was dead. The battle persisted and Megalodon dived deeper and deeper until the Pod members of the victim released it or they would have run out of breath." Technically this many be percieved as a defeat for the Megalodon by some but it sounds like a stalemate to me. It would have been an energetic costly venture for pack predators to tackle a considerably larger animal. Even in modern times, it may take hours to kill even defenseless whales by pack predators.
Also when a predatory shark as damn big as a Bull Sperm Whale would attack a prey item - it would not need to solely rely upon stealthy attacking strategies unless the prey item is significantly faster. Have a look at the Megalodon's attacking strategy depicted in this documentary from Discovery Channel: Long Ago in the Chesapeake Bay. The attacking strategy is swift but direct, dominating, and not stealthy as Megalodon approached from the right side. The whale was trying to escape but couldn't. While I am open to your views, you should be open to mine and stop deleting referenced information that I may contribute without valid reasons or properly checking the sources. I have played a major role in up-lifting of this article. Most of the content presented in the article has been provided by me.
LeGenD (talk) 06:14, 27 December 2009 (UTC)
I just had a look at the video segment. It shows the shark and its prey swimming at right angles, with no obvious turning or evasive behavior by the prey. So, this might be interpreted as a stealth attack. I'm not convinced that a stealth attack from such an angle makes sense; coming up from below as great white sharks usually do seems more likely. WolfmanSF (talk) 09:27, 28 December 2009 (UTC)
The Megalodon was moving faster than the prey item. To date, fossils of several whale specimens have been found that indicate that Megalodon attacked and tore through their pectoral fins, upper spine, and rib cage in an attempt to kill them. The attacking strategy shown in the Discovery Channel video mimics this kind of predatory behaviour. Here is another example from BBC. This particular whale specimen (a Bowhead whale to be more precise) was attacked like this: The animal which attacked this whale, went straight for the pectoral fins; the rib cage; the middle of the body. Of-course! Megalodon would not always attack a prey in this manner. In the National Geographic Show, Megalodon was revealed to have attacked different kinds of prey in different manner, depending upon their size and speed.
LeGenD (talk) 03:42, 28 December 2009 (UTC)

I have merged content of interspecific competition section with range and habitat section and expanded information in several sections with new references. Their is better correlation between information presented in different sections now. LeGenD (talk) 19:16, 30 July 2010 (UTC)

Within the extinction section; the heading "increased competition" does not makes sense. Competition was much greater during Miocene then in Pliocene. The only difference is that C. megalodon was in decline due to oceanographic changes. The appropriate title should be "Competition and ecological succession" or simply ecological replacement. Since the information presented covers the aspect of ecological replacement of C. megalodon as well.--LeGenD (talk) 22:51, 17 April 2010 (UTC)
"Ecological succession" (please check out the linked article) normally refers to "predictable and orderly changes in the composition or structure of an ecological community", so it doesn't seem like a good fit to what we're discussing here. The species replacements we're discussing weren't obviously predictable. In my view, it is also too general and distracts from the main point of the section.
"Increased competition" refers to the appearance of a new and more advanced competitor - the orca. That is, we are not simply talking about the number of competitive species, but about how efficient they were as predators. Also, we need to take into account the size of the food supply relative to the amount of competition, and changes in environmental conditions relative to the environmental preferences of the competition. If the cetacean prey population declined, and and the population of competing predators also declined but in smaller proportion, then the level of competition might be viewed as having increased. If environmental changes were more advantageous (or less of a disadvantage) to competing predators than to C. megalodon, competition might be viewed as having increased. Competition may or may not have been a significant contributor to C. megalodon's demise, but it it was, it would have had to have increased.
The whole point of this section is to present an alternative possible cause or contributing factor for C. megalodon's extinction. We should not be re-emphasizing too much the possible role of oceanic cooling here because (as Robert Purdy points out) we simply don't know which factors were most important. WolfmanSF (talk) 19:10, 17 April 2011 (UTC)
Regarding competition hypothesis: The title "increased competition" would give impression to the 'casual leader' that competition increased during Pliocene then in previous epochs, which is inaccurate. Also, this 'alternate view' is coming from some books and not from research papers. Books can contain questionable data, fictional material, and outdated views. To be honest, we would never know that competition was a problem for C. megalodon even during its struggling phase. Just because an Orca was documented to have taken out a juvenile great white (1997 incident) - does not proves that ancient relatives of this species outcompeted C. megalodon. Even the names of paleontologists have not been provided in the relevant source, which presents this hypothesis. Possibility of attack on small pups (neonates) of C. megalodon is acceptable view. However, this is not sufficient reason to cause demise of a dominant species. Infant mortality is common phenomenon in nature. Seriously! Think about this; despite of supremacy of Orca in the oceans - great white shark thrived. This species is endangered due to activities of man. Orca never wiped this species out or any other competitive shark species. Furthermore, adult individuals of C. megalodon would have been virtually unchallenged. This is why this 'alternate view' is not given much credence in the scientific community. Only some 'mammal enthusiasts' like to boast about this hypothesis. In reality it is just a speculation. Robert Purdy has not supported 'competition hypothesis' either. In addition, his comment was focused on marine vertebrates and not on oceanic cooling.
Ecological succession: You presented one view of this concept. The other view has been explained in the article: "The ancient relatives of the orca evolved during the Pliocene,[54] and likely filled the ecological void left by the disappearance of raptorial sperm whales at the end of the Miocene.[39]" This is natural way of ecological replacement (more appropriate term) in nature in case of living organisms. Here is quote from relevant research paper (The giant bite of a new raptorial sperm whale from the Miocene epoch of Peru):
-> "Further data on the timing of this extinction and the appearance of large raptorial delphinids during the Pliocene will be crucial to investigate further this marked ecological replacement and its relationships with other late Neogene events."
Regarding oceanic cooling hypothesis: This is tested hypothesis. This hypothesis is supported by fossil evidence, and is widely accepted. Robert Purdy acknowledged in his research paper (paleoecology of fossil white sharks) that C. megalodon preferred warm waters and C. carcharias preferred cool waters. Here are some quotes from his research paper:
-> "The small-toothed species preferred cool temperate waters and avoided areas preferred by the giant-toothed species."
-> "In the western North Atlantic basin, the giant-toothed Carcharodon used warm-water areas for nurseries, while the small-toothed species line used cool waters."
-> "The abundance of C. carcharias in the Pliocene may be related to the spread of cold waters toward the equator."
-> "Judging from the available fossil evidence, in the late Eocene, the giant-toothed species, along with archaocete whales (Mitchell, 1989), inhabited the temperate waters of Antartica (Welton and Zinmeister, 1980; Long, 1992), but whether or not these sharks continued to live in these waters as they became more boreal is not preserved in the fossil record. The available data indicates that they preferred warm seas (Fig. 1)."
Several other research papers also acknowledge this case. Here is quote from one such research paper (from year 2010):
-> "It occurs in Pliocene beds from Farol das Lagostas near Luanda, Angola, definitely in association with the maybe last representatives of the huge Carcharocles megalodon (Agassiz, 1843) see Antunes (1978). The latter is a well known Miocene form that seems to have been severely hit by main oceanographic changes by the end of the Miocene and as a result became scarcer and increasingly rare until its ultimate extinction, maybe in Pleistocene times. A Pleistocene age was accepted for great depth, bottoms’ phosphatised fossil teeth, but they may be older in hard ground conditions where heterochrony may be very marked. The white shark seems to have gained from the extinction of this formidable counterpart. It acquired an increased importance and a very broad distribution."
This paragraph explains it all. Think about this; if C. megalodon could thrive in cool waters - what stopped it from venturing in to polar regions to look for prey? And we know that by the time C. megalodon became scarce; Ice Age and glaciation was on the horizon. So give emphasis to research papers rather then to some books from amateurs in the field. I propose "ecological replacement" as suitable heading.
LeGenD (talk) 23:01, 18 April 2011 (UTC)
Sorry, but I take issue with some of your comments. Your statement that "this [infant or juvenile mortality] is not sufficient reason to cause demise of a dominant species" has no basis in fact or theory. Any cause of mortality that becomes sufficiently large can take out any species, no matter how dominant it was initially. Your proposal that competition did not increase during the Pliocene can't be very secure if you also believe Robert Purdy when he says that "There is not much evidence for the history of marine vertebrates for the last three million years". Regarding your claim that "despite of supremacy of Orca in the oceans - great white shark thrived". Yes - but probably only in areas where orca are absent, as the "Showdown at Sea" article indicates. "Furthermore, adult individuals of C. megalodon would have been virtually unchallenged" - here you may be missing the point. Competition between predators isn't simply a matter of head-to-head battles for supremacy. In many cases, its just a matter of who can get the vulnerable prey individuals first. All the large prey that orca took were unavailable to C. megalodon, reducing its food supply.
As far as I'm concerned, the section heading "Ecological replacement" is unacceptable. It does not indicate or suggest a cause of extinction. It simply describes the fact that some species disappeared and others appeared. The whole point of this section is to indicate the possible causes or contributing factors behind the extinction. WolfmanSF (talk) 08:56, 1 May 2011 (UTC)
Sorry, but I take issue with some of your comments.
And I take with some of yours because you only put faith in your views and don't check the sources properly. With this type of mentality, you will only cause editing wars. Before you plan to make your next edits, can you bother to discuss your points here or notify me? Coz you are not being helpful here.--LeGenD (talk) 4:50, 01 May 2011 (UTC)
Here is elaboration:
The Pliocene closure of the Central American Seaway (complete by ca. 3.1 Ma) coincided with significant environmental and faunal changes in the Caribbean as well as the eastern Pacific (Jackson et al., 1996); in particular, there was an extinction of shallow-water molluscs in the Caribbean and West Atlantic, apparently correlated with changes in salinity and circulation patterns (Vermeij, 1978; Stanley and Campbell, 1981; Keigwin, 1982; Petuch, 1982; Jones and Hasson, 1985; Duque-Caro, 1990). Allmon et al. (1996) also point out Late Pliocene changes in assemblages of calcareous algae and plankton, as well as regional extinctions among turritellid gastropods, seabirds, cetaceans, and pinnipeds, and extinction of the giant shark Carcharodon megalodon.
In (Sirenians, seagrasses, and Cenozoic ecological change in the Caribbean)
Now from Allmon in his newer paper;
The record of whales may, furthermore, be linked to that of the extinct giant white shark Carcharocles megalodon. The Lower Pliocene Tamiami Formation represents the youngest Florida record of this animal, which reached lengths of more than 13 m (Randall, 1973). The common occurrence of C. megalodon bite marks on baleen whale bones from the Tamiami Formation at Sarasota (e.g. Spizuco et al., 1993) indicates that whales constituted at least a portion of this large shark's diet. The extinction of C. megalodon at or near the end of the Early Pliocene may thus have been due at least partially to the disappearance of great whales from the low-to-mid latitudes of the western Atlantic (Morgan, 1994b).
In (Nutrients, temperature, disturbance, and evolution: a model for the late Cenozoic marine record of the western Atlantic)
The authors clearly have presented a correlation between extinction of C. megalodon and that geological event (formation of Isthmus of Panama) which concided with environmental and faunal changes. (Faunal changes can work like a chain reaction starting from a certain point and leading to demise of many within a span of time). You can't interpret material in the scientific papers?--LeGenD (talk) 4:50, 01 May 2011 (UTC)
Your statement that "this [infant or juvenile mortality] is not sufficient reason to cause demise of a dominant species" has no basis in fact or theory. Any cause of mortality that becomes sufficiently large can take out any species, no matter how dominant it was initially.
And you pretend to know anything about infact mortality in case of C. megalodon? Show me some research in this regard, if any.--LeGenD (talk) 4:30, 01 May 2011 (UTC)
Your proposal that competition did not increase during the Pliocene can't be very secure if you also believe Robert Purdy when he says that "There is not much evidence for the history of marine vertebrates for the last three million years".
I stand by my point. Focus on paleontological findings of Miocene fauna and you will learn that considerably larger and more ferocious raptorial odontocetes existed back then. And if fossil evidence is scant during Pleistocene, you won't be able to justify a correlation between extinction of C. megalodon and large delphinids either.--LeGenD (talk) 4:50, 01 May 2011 (UTC)
Regarding your claim that "despite of supremacy of Orca in the oceans - great white shark thrived". Yes - but probably only in areas where orca are absent, as the "Showdown at Sea" article indicates.
Oceanic environments are enormous enough to accomodate a large variety of niches, and scientific literature actually suggests that these two animals may only compete with each other where dietary preferences may overlap. Still such interactions are rare.--LeGenD (talk) 4:50, 01 May 2011 (UTC)
Also, a documentary from National Geographic (The Whale That Ate Jaws) reveals another side of story as well - chunks bitten out of killer whales which may pursue sharks. Also, the shark taken out by CA2 was noticeably smaller in size.--LeGenD (talk) 02:50, 01 May 2011 (UTC)
"Furthermore, adult individuals of C. megalodon would have been virtually unchallenged" - here you may be missing the point. Competition between predators isn't simply a matter of head-to-head battles for supremacy. In many cases, its just a matter of who can get the vulnerable prey individuals first. All the large prey that orca took were unavailable to C. megalodon, reducing its food supply.
Then clarify this point in the article by citing suitable sources, if possible. A layman is getting a different impression from existing content.--LeGenD (talk) 4:50, 01 May 2011 (UTC)
Nevermind. I have appropriately fixed the content now.--LeGenD (talk) 02:52, 02 May 2011 (UTC)
As far as I'm concerned, the section heading "Ecological replacement" is unacceptable. It does not indicate or suggest a cause of extinction. It simply describes the fact that some species disappeared and others appeared. The whole point of this section is to indicate the possible causes or contributing factors behind the extinction.
Whether you like it or not, scientific studies are supporting the case of ecological replacement. C. megalodon was being replaced by new apex predators where water temperatures were declining. I already cited scientific papers which corroborate with my point (see above). Same would be true for delphinids. This ecological replacement could have been misinterpreted by some as a sign of competitive displacement. The real facilitating factor was the spread of cold waters. Below is a one of the latest sources which explores the extinction theories on C. megalodon:
Prehistoric Predatos from National Geographic on YouTube
Now point to me that which experts support a correlation between extinction of C. megalodon and large delphinids? This is certainly not a popular hypothesis.--LeGenD (talk) 4:50, 01 May 2011 (UTC)
I have refined the content in the entire extinction section. Irrelevant material has been removed. No one should have issues with the content now. However, if someone still has issues, let me know first or mention them here.--LeGenD (talk) 7:10, 01 May 2011 (UTC)

Extinction

not a productive or even useful thread
The following discussion has been closed. Please do not modify it.

There have been theories that megalodon existed until 10,000 years ago, and even that it is still extant. Should this be in the article? - Richard Cavell (talk) 12:06, 18 December 2009 (UTC)

I have covered this part in the In fiction section and it seems to fit in appropriately.
LeGenD (talk) 02:29, 10 January 2009 (UTC)

megalodon was an Evolutionary failure, probably got wiped out by Killer Whales Metamorphosed Fossil (talk) 09:12, 17 October 2010 (UTC)

Um, in case you haven't noticed, Megalodon was around for about 20 million years - that's hardly a "failure." Like all organisms, there may come a time when environmental changes happen faster than a species can react. I've also deleted your off-topic/soapbox/forum comment below that violates Talk Page rules. Please, try to act like an adult on Wiki or you can be reported/banned. HammerFilmFan (talk) 03:38, 11 September 2011 (UTC)
Your assumptions are childish and lack maturity. Stop embarrasing yourself with useless rants. If you have got something concrete to share, then please do so. Otherwise, let (the more 'well informed' members do their job). Also, you make it sound like as if killer whales had personal vendetta against C. megalodon - very illogical assumption. --:LeGenD (talk) 22:22, 13 April 2011 (UTC)
Mammals, Reptiles are far more Intelligent and far more advanced and Superior than primitive lifeforms like fishes which includes sharks. So you must be the fish cause im the mammal Metamorphosed Fossil (talk) 10:51, 3 September 2011 (UTC)

1918 Port Stephens Shark

I suppose most, if not all, scientists don't take the 'alleged' sighting of a giant white shark off the coast of Port Stephens, Australia in 1918 seriously. This giant shark was said to be about 80 feet long and swallowed crayfish (lobster) traps whole. I am only metioning it, because, if I don't write about it, someone who read about the story is going to ask about it. It is a very infamous "fish tale" about the ultimate fish which got away. A lot of books about sharks, and 'mysteries' of the ocean, do bring it up.204.80.61.110 (talk) 16:03, 12 January 2010 (UTC)Bennett Turk

this giant shark did not survive unfortunately, and was hunted down by a pack of Killer Whales Metamorphosed Fossil (talk) 09:17, 17 October 2010 (UTC)

Yet the killer whales failed to wipe out great white shark, Carcharodon carcharias (another competitor)? Try to use common sense.--LeGenD (talk) 22:27, 13 April 2011 (UTC)

An Error

"over 28 times greater than that of Dunkleosteus at 6.3 kN (6,300 lbf), over 10 times greater than that of great white shark at 18 kN (4,100 lbf), over 5 times greater than that of T. rex at 31 kN (7,000 lbf), and also greater than that of Predator X at 150 kN (33,000 lbf)."

So 6.3 kN = 6,000 ibf. But 18 kN is only 4,100 kN? Also how and why do you suppose a GWS can exert that? They hunt fleshy things (like seals) not crustaceants (like the nurse shark does). A show measured many animal bite forces, the GWS and Nurse Shark were two of them. They excerted <400 and ~1000 pounds respectivly. So the mis types need fixed, and probally so do the forces them selves. Spinodontosaurus (talk) 14:22, 26 January 2010 (UTC)

Thanks for pointing out the error. I have fixed it. And for your query on great white shark's jaw power, a reference has already been provided to ascertain the information. The 18000 Newtons jaw power is of a great white shark more than 20 feet long. So it sounds valid and justifiable as the experiment by S. Wroe confirms. Nurse sharks do not grow as large.
LeGenD (talk) 15:17, 07 Feburary 2010 (UTC)

Leedsichthys is a larger predator than megalodon Metamorphosed Fossil (talk) 09:13, 17 October 2010 (UTC)

Leedsichthys is a micro-predator. C. megalodon is a macro-predator. Also, whether Leedsichthys was larger or not is debatable.--:LeGenD (talk) 22:31, 13 April 2011 (UTC)

complete fossil remains of Leedsichthys have been found, as this fish is made up of bone and not cartilage. Metamorphosed Fossil (talk) 11:08, 3 September 2011 (UTC)

There are no complete fossil remains of Leedsichthys: if you had ever bothered to read the article, all of the remains found so far have been fragmentary.--Mr Fink (talk) 04:35, 11 September 2011 (UTC)

Basilosaurus, Kronosaurus, Liopleurodon, Mosasaurus, Tylosaurus, Megalodon, Deinosuchus etc etc were all in similar dimensions and we should give up our immature ways as to whether whos larger. Evolution does not favour which class you belong whether you a fish, reptile or mammal Metamorphosed Fossil (talk) 12:26, 3 September 2011 (UTC)

And yet, it is in Wikipedia's best interest to inform readers on the dimensions of each such creature. Plus, you contradict your other claim that Megalodon was driven to extinction by the oh-so-evolutionarily superior killer whale.--Mr Fink (talk) 04:35, 11 September 2011 (UTC)

Infobox image

Old image of AMNH jaws
New image

The new infobox image is hardly better than the previous one, which contains actual teeth and was taken by a Wikipedia user, the new one seems to be all reconstruction and had some iffy license information (no confirmed OTRS), it is noisy, distorted by perspective, and badly cropped. I'd prefer the old one back. FunkMonk (talk) 17:56, 30 March 2010 (UTC)

I think that you like the first one better. However, the second one represents a larger Megalodon (makes sense, since current estimates are very high once again). Also, when you view the image at full size, you can notice that the jaw reconstruction is very well done and also shows replacement teeth. The license is assigned to it according to the wishes of its author (Creative Commons ShareAlike 3.0). It is good enough to be used in the main article and I will use it.--LeGenD (talk) 12:32, 30 March 2010 (UTC)
I have made some adjustments to the images used in the main article and also improved their descriptions. Things should be fine now.--LeGenD (talk) 12:59, 30 March 2010 (UTC)
Oh, there is nothing wrong in using it, article wise. The problem is just that you need the permission confirmed through the OTRS process on Commons, you need to send them the mail wherein you got permission, otherwise the file is effectively a "no source" image, and could get deleted. FunkMonk (talk) 22:01, 6 April 2010 (UTC)
I have proper permission through email from the author of this image for its use in wikipedia. I am familiar with copy right issues. However, can you elaborate on the OTRS process on Commons?
--LeGenD (talk) 16:55, 07 April 2010 (UTC)
Yeah, if you already have the mail, you can just resend it to the OTRS guys I think, check this: http://commons.wikimedia.org/wiki/Commons:OTRS FunkMonk (talk) 15:52, 8 April 2010 (UTC)

Too Good

I think this article, its overall tone and such, glorify the Megalodon a little too much. it also seems to make whales and other cetaceans seem inferior or incompetent. It should be changed so it sounds like it's describing an animal, and not an action hero. Star Hound (talk) 03:22, 10 April 2010 (UTC)

Glorify in what sense? This was a giant predator that ate cetaceans. Is this difficult to understand? Just go through all of the provided sources and than make up your mind. If you have any suggestions than please provide them here. I will see what I can do.
LeGenD (talk) 10:50, 11 April 2010 (UTC)
I agree that some parts tended to sound a little sensationalized. I removed some obvious sensational language, but a big problem still remains. I think a lot of this unscientific tone comes from the fact hat the biggest single source in the article is a TV documentary. Ask any paleontologist, those things are far from scientific sources. I think anything and everything stated in TV show sources needs to be checked against peer-reviewed literature, and if they can't be corroborated, the claims need to be removed. We should follow sources written by scientists, not TV writers looking to make cool scenes. MMartyniuk (talk) 07:02, 11 April 2010 (UTC)
You can see the Monster Shark episode from National Geographic here. It is split in to 5 parts and is in a foreign language. However, it is the most reliable documentary yet produced with lots of experts consulted. I intend to use it as a source because it covers those aspects of research which are normally not provided in the written literature.
LeGenD (talk) 13:53, 11 April 2010 (UTC)
I haven't seen it in English and NatGeo shows are usually much better than Discovery, etc. But normally, if a show covers territory not covered in the literature, it may be because it's not appropriate for the literature, i.e. lots of (albeit professional) speculation. Also, just because experts are consulted doesn't make it accurate. Case in point. Anyway, my main concern is that normally, the "good" documentaries simply repeat things from the lit. The really excellent Nova special on Microraptor is not cited once in that article. It could, given the quality, but everything covered in the show is also covered in the lit. The Nova show is only mentioned under popular culture since it is, really, a popular show and not scientific research. It sets off alarm bells for me, and I'm sure anyone else trying to separate science from entertainment, when a popular TV program outweighs scientific research in this article. MMartyniuk (talk) 23:40, 11 April 2010 (UTC)
This documentary covers most aspects of research that have been done on the Megalodon to date and also provided within the written literature (e.g. bite force experiment, an associated set of dentition, fossil evidence of prey items, Megalodon skeletal reconstruction, Megalodon jaw reconstruction etc.). In short, it provides an up-to-date view of the animal and its purpose is to educate and not create a sensation. I would recommend this documentary to any person. The problem with Megalodon is the lack of sufficient sources on it or access to them. Due to this limitation, I have little choice but to make do with whatever resources are available. However, I do appreciate any suggestion.--LeGenD (talk) 10:13, 12 April 2010 (UTC)
"This documentary covers most aspects of research ...also provided within the written literature." Isn't it redundant, then? It should be easy using ref lists in books and related papers and Google Scholar to track down the actual research papers, rather than citing a secondary source that merely discusses their findings, not their detailed methods. In fact, pruning the article today, I found that the "fact" the show was one of the biggest sources was an illusion anyway. Almost half of the cites to it were redundant with primary sources. I don't think there's a need to cite a science paper, and also a show that happens to discuss the paper, right next to each other. The paper is enough, the show should be listed under "Further reading/information" or something. Unless it's the only cite, and it may be a problem if a specific claim is coming ONLY from the show. I think these insances would be ok if it's an expert making the claim on air. For example, "In the NatGeo documentary Monster Shark, scientist x claimed y." Rather than "Claim x (cite: MonsterShark)". In the latter, who is making the claim? TV writers? Producers? Or experts? There needs to be more context. Some of the stuff I removed today was along the lines of "Megalodon was the most ferocious vertebrates of all time." No scientist would make such a hyperbolic statement, and it sounds more like producer speak to me. If it's ambiguous who is even making a claim, let alone how they tested it, it's not a very reliable source. MMartyniuk (talk) 06:33, 12 April 2010 (UTC)
I think that you need to straighten up your mind. First you claim that if a documentary covers those aspects of a subject which are generally not discussed in written literature, than those aspects are questionable. And than you claim that if a documentary also covers details that have been discussed in written literature than the documentary is useless to cite. You are trying to find an excuse to restrict the use of even reliable documentaries for citation purpose. Let me make this clear to you - I give more priority to educating readers rather than ratings of articles. If I am contributing in an article, than I would try to cover all aspects of research done on the subject, be it through written literature or through documentaries. Just watch the documentary recommended by me and than make up your mind. It is idiotic to critcise a source without properly checking it. And I generally avoid sources with controversial history for references (e.g. Jurassic Fight Club). I know that which sources are good enough to cite on this subject. I am surely open to suggestions and help (since this is also consistent with official policy of wikipedia) from other editors but this liberty should not be misused. Also, you need to check sources more carefully. On Megalodon being most formidable creature - The threatened white shark Carcharodon carcharias, is the world’s largest extant predatory fish. Its gigantic, whale eating relative, Carcharodon megalodon, was arguably the most formidable carnivore ever to have existed (Gottfried, Compagno & Bowman, 1996; Purdy, 1996). These lines have been provided in a written literature: (ref no. 21) Three-dimensional computer analysis of white shark jaw mechanics: how hard can a great white bite?. Deletion of content cited through good sources do not make sense to me. And I would caution any person against starting an editing war. It will not help any one. Point is that you cannot satisfy the entire world. People will continue to nit-pick on points here and there. Please do make a contribution but in the positive sense (I would surely encourage you). You are a famous contributor in wikipedia and I expect positive contributions from you. Thank you. --LeGenD (talk) 21:40, 12 April 2010 (UTC)
Published papers are preferrable over TV documentaries, remember, Wikipedia is about reliable sources. TV documentaries aren't reliable sources in themselves. FunkMonk (talk) 18:36, 12 April 2010 (UTC)
Of-course! I use documentaries for citation where it becomes absolutely necessary and their are no other options. I am sure that fellow editors can understand this limitation. Since Wikipedia does allows citation of videos, I believe that I have not violated any rules. With passage of time, if new written literature will arrive, I will make appropriate modifications accordingly.--LeGenD (talk) 10:55, 13 April 2010 (UTC)
"I give more priority to educating readers rather than ratings of articles." You make it sound like this is "your" article. This is all of our article. This is Wikipedia, not your personal web site. :"On Megalodon being most formidable creature - The threatened white shark Carcharodon carcharias, is the world’s largest extant predatory fish. Its gigantic, whale eating relative, Carcharodon megalodon, was arguably the most formidable carnivore ever to have existed" So put it in quotes, this is clearly the opinion of those authors, not a scientifically tested fact. Anyway, the point is kinda moot now, the source is still in there on a variety of points and I tihnk between my edits and your subsequent ones we've addressed the concerns of the OP here. The sections in question have a much more neutral tone now. MMartyniuk (talk) 01:12, 13 April 2010 (UTC)
You actually misunderstood my point and you have over-reacted. I never claimed that this is my article but let us be honest - I have been the main contributor in it. Of-course! This article is for every person and every person is free to contribute and does contributes. This does not even needs to be reminded to established contributors. My track record clearly shows that I am as neutral as possible when it comes to contributing in wikipedia. See some examples above. My point is that people can have different opinions on a same subject. Critizim is bound to occur. However, we cannot accomodate every point of view unless a strong case is provided. Other than this, your support is appreciated. Also, with passage of time, new literature may occur, so this isn't the end of our contributions and neither it should be treated as such. I agree that content has more neutral tone now. With colloboration, we have a better chance to improve an article. Thank you! Once again! --LeGenD (talk) 11:02, 13 April 2010

I've changed the article a bit. I made it clear that Megalodon was not superior or better than any of the toothed whales that coexisted with it, and I removed the idea of it eating sperm whales, because I am unable to find any evidence of the animal eating sperm whales. Star Hound (talk) 16:58, 2 May 2010 (UTC)

Are we dealing with a cetacean fan here? Is it up to you, Star Hound, to decide that how influential Megalodon was? We are talking about a 50+ foot 50+ ton macropredatory shark (a superpredator) that preyed upon cetaceans and not some 500 kg weasel. And if you cannot find the evidence for predation on sperm whales, ask here before deleting any content. Here are some FACTS for you:
1. Most of the odontoceti competitors became extinct during Miocene (including the killer sperm whales and squalodontids). What forced these animals to extinction? Food sources weren't scare during Miocene.
2. Orca like dolphins arrived during Pliocene but they adapted to cold water temperatures like the great white shark and survived.
3. On Megalodon's predation on Sperm Whales: "50 foot Sperm and Baleen whales were also Florida residents, and of course, part of Meg's diet." (Page 60 of book: Megalodon Hunting the Hunter). Another indication is here The lines are: "Megalodon means "big tooth." It is obviously not a mammal, although it did eat many, including the large Sperm whale." If this is not enough than I also had personal communication with a paleontologist Steve A. Alter on Megalodon's predation on sperm whales. This is his reply: "The bones from Sperm Whale and Baleen Whale are very similar I think but there are so many that it is definitely both species. I have even seen bite marks on the roots of Sperm Whale teeth so that is 100% evidence." In addition, paleontologist Robert Purdy found evidence of Megalodon's fossils in association with fossil remains of large whales (including large sperm whales) in the LeeCreek region, indicating predation (see chapter 8 of book: Great white sharks: the biology of Carcharodon carcharias By A. Peter Klimley, David G. Ainley).
4.Even great white sharks are known to attack and kill pygmy sperm whales.
5.Unfortunately! Lots of discoveries related to Megalodon do not get sufficient publicity. Hence, we have shortage of written literature on this subject and are forced to make do with whatever we have got at hand.
Try to make positive contributions. Thank you.--LeGenD (talk) 10:57, 03 May 2010
Update; here is an example of predator-prey interaction between C. megalodon and a large Sperm whale: C. megalodon bitten large Sperm whale vertebra. --LeGenD (talk) 20:57, 13 April 2011

There is a question regarding this at the bottom but personally I believe that Megalodon was only 12 metres long and weighed 20-30 tonnes (40 tonnes max), since to me the idea of +15 metre and +30 tonne predatory shark is just, no offence, ridiculous. — Preceding unsigned comment added by 112.134.201.190 (talk) 14:58, 7 June 2014 (UTC)

New paper on Megalodon nursery areas

And it's in PLOS, so it's free, and we can use their images and text: http://www.ploscollections.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010552;jsessionid=98877ADBE526C9F39CB33DF115FE0694 FunkMonk (talk) 06:46, 11 May 2010 (UTC)

Cannibalism as a reason for extinction?

The section quite clearly explains Megalodon's cannibalistic tendencies but only its inclusion into the Extinction section hints that cannibalism may have led to the extinction of the species. Can the section clearly say that that is a possibility with (of course) references to back it up? It might seem obvious that cannibalism was partly responsible for the extinction, but the number of successful cannibalistic fish that are alive today is quite large. Surtsicna (talk) 17:08, 1 July 2010 (UTC)

Cannibalism can't have been the primary cause of extinction, otherwise C. megalodon would never have survived so long. The idea that it was a contributing factor sounds logical but is basically speculation. I don't think this hypothesis deserves much emphasis. WolfmanSF (talk) 19:45, 1 July 2010 (UTC)
So, will it be removed? Surtsicna (talk) 19:57, 1 July 2010 (UTC)
I'm not advocating that, just that it not be expanded much. WolfmanSF (talk) 21:43, 1 July 2010 (UTC)

I moved the text from that section to the one that discusses its prey. I am afraid that keeping it in the Extinction section without a source saying that cannibalism caused the extinction would be WP:SYNTHESIS. Surtsicna (talk) 09:49, 2 July 2010 (UTC)

Why is it a Cryptid?

If the Megalodon is a cryptid how come there are no undigested remains of both least concern and endangered cetacean species littering the ocean floor or attacks on ships due the classic case of mistaken identity so why is it in that catagory? in order to maintain such a monster of a shark would require a vast ammount of food meaning that the efforts of protecting marine life would have been wasted since a Megalodon female would have eaten every last species just to prepare for repoduction the notion of such a monster still living today is beyond insanity. So answer the riddle why this unstoppable killing machine a cryptid? remember this animal requires more food than any living fossil up to date —Preceding unsigned comment added by Crypto457 (talk • contribs) 18:06, 28 July 2010 (UTC)

The term "cryptid" is not applied to a scientifically verified genus; rather, it is applied to animals that have not yet been proven by science to exist, yet there's still a possibility that they do exist. Take Bigfoot as an example. Many researchers agree that Bigfoot should be classified as a real creature, but the scientific community does not yet accept this. The same principle applies to El Chupacabra and the Loch Ness Monster. As for C. megalodon being a cryptid, I think it's very possible. C. megalodon probably did not consume as much as you suggest, and although whales (most likely their primary food source) are endangered, there are still several hundred, if not several thousand, still alive and in the ocean today. A single C. megalodon wouldn't be able to consume every single whale alive today. If it could, then there's no doubt that C. megalodon wouldn't have survived for as long as it did during its time period. The Raptor Let's talk/My mistakes; I mean, er, contributions 19:48, 28 July 2010 (UTC)
If there was a megalodon alive today, wouldn't people be finding fresh teeth?--Mr Fink (talk) 20:04, 28 July 2010 (UTC)
Not necessarily. Chances are, if it lived in shallow water where we would find the teeth, we would've found one by now. If there are still C. megalodon alive today, they'd probably be living in the deep ocean. When they shed their teeth the teeth stay at the bottom of the deep ocean. In fact, there are teeth from C. megalodon that are millions of years old and haven't been found because they're in deep water. So if we haven't found teeth, it probably indicates the C. megalodon (might) live in deep water. The Raptor Let's talk/My mistakes; I mean, er, contributions 20:15, 28 July 2010 (UTC)
You forget that the argument that "Megalodon isn't dead, it's just hiding very well" has been brought up before, and it remains unconvincing. That, and all of the Megalodon teeth that have been dredged up from the bottom of the ocean (and there are numerous) are already fossilized.--Mr Fink (talk) 02:26, 29 July 2010 (UTC)

males may not eat as much meat but the females maybye the bigger problem and besides a species like that cant hide forever, think of it if they are still alive and have a population wouldn't the EPA and World Wildlife Foundation take notice that the poulations of modren marine life have disappeared but the fishing boats were not in the area where the species vanished just look at the behavior of the descendent the Great White if that species can do damage to humans just imagine a megalodon doing the same thing it would make Jaws look like Finding Nemo, where as the issue of the chupacabra is completly diffrent(Crypto457 (talk) 23:38, 28 July 2010 (UTC))

You're forgetting that we know more about the surface of the moon than we do about the deep blue. The Raptor You rang?/My mistakes; I mean, er, contributions 13:22, 30 July 2010 (UTC)

Um are you suguesting that these extinct killing and eating machines might exist if thats the case wouldnt the marine life populations dwindle faster I mean really what kind of food scource that could keep up the needs of a population of these monsters? —Preceding unsigned comment added by Crypto457 (talk • contribs) 06:53, 1 August 2010 (UTC)

IF, and that is a very big and highly unlikely if, C. megalodon is still alive, the the ocean food chains would have had sine the MIOCENE to have formed an equilibrium which included it. Your scenario of massive prey depletion would have played out millions of years ago and the debate would be moot as C. megalodon would be extinct. Common sense shows that if sperm whales can have survived with stable population numbers then C. megalodon would hypothetically have too.--Kevmin § 07:14, 1 August 2010 (UTC)

Requested move

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the move request was: Result: The consnsus is to not move the page. ~~ GB fan ~~ 16:22, 9 September 2010 (UTC)


Megalodon → C. megalodon — It appears that a bivalve with the genus name Megalodon (bivalve) exists, so this article should probably be moved to C. megalodon, and the bivalve should be moved to Megalodon, as it would have priority. FunkMonk (talk) 16:13, 31 August 2010 (UTC)

Yep, standard WP paleo practice is to give whatever topic used the name first the name. An alternate title for this one could be Megalodon (shark), since "Megalodon" seems to be the default common name for C. megalodon. MMartyniuk (talk) 23:42, 31 August 2010 (UTC)
Yeah, but even within this article, C. megalodon is most commonly used. Looks better than a title in paranthesis too, and is easier to manage... FunkMonk (talk) 18:49, 2 September 2010 (UTC)
The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Most formidable/powerful/largest marine predator

I think Megalodon could be stated as the largest and most powerful predator knwown, since current max size estimate for Dr Gottfried and Cliff Jeremiah, the most reliable today, indicate a shark heavier than a sperm whale (though not necessary longer), still bigger than the only specimen of Lyviatan melvillei, and both larger and heavier than the biggest jurassic pliosaurs (Predator X/Monster of Aramberri are estimated liberally at 45/50 tons).

Some would say that the Blue Whale is the largest predator ever since she eats krill, but currently, and even on some scientific or very serious papers, the Blue Whale isn't claimed as a predator or the largest predator, because the fact that many species of marine predators from the pasts have been stated sometimes as the largest predator that ever lived (giants piosaurs, shonisaurus sikanniensis, C.megalodon, lyviatan melvillei or modern sperm whales).

Also, in the light of the new largest teeth of the last years, Megalodon adults are widely regarded as reaching possiby currently 18 metres and 77 tons. —Preceding unsigned comment added by 78.250.45.254 (talk) 12:59, 9 April 2011 (UTC)

Carcharocles

Carcharocles currently redirects here, which is far from ideal. It should either have its own article or redirect to a higher level taxon where the Carcharocles vs. Carcharodon debate can be covered, possibly at Lamnidae or Otodontidae. As it stands, Carcharocles angustidens, Carcharocles auriculatus, and Carcharocles chubutensis are without a parent article. Thoughts? mgiganteus1 (talk) 01:55, 25 August 2011 (UTC)

I think we should give Carcharocles its own article, even if it's just to list the different species. Perhaps we could also move the "Carcharocles versus Carcharodon" debate there, too?--Mr Fink (talk) 04:55, 11 September 2011 (UTC)

In Fiction

while this is completely irrelevant to the content of the topic, i couldn't help but notice that the "in fiction" section states: "Mega Shark Versus Giant Octopus (2009) and its sequel [...] are parodies of disaster films [...]". now i am not entirely convinced that they are really intended to be parodies, also i couldn't find any relevant sources to confirm this claim. (i'm curious now, i might actually watch them...) --Phneutral (talk) 18:13, 28 October 2011 (UTC)

Am I correct in assuming that Discovery Channel's new "documentary" entitled "Megalodon - The Monster Shark Lives" is another "fakeumentary" (I made up that word) written and produced by the same people that gave us "Mermaid - The Body Found"? I remember when Discovery had real science shows on it. — Preceding unsigned comment added by Jonnyhabenero (talk • contribs) 05:26, 5 August 2013 (UTC)

To whatever extent it suggests megalodon may not be extinct, yes. WolfmanSF (talk) 05:35, 5 August 2013 (UTC)

I don't think the Discovery Channel show should be listed as "fiction". It is a competing and unorthodox hypothesis that theorizes that Megladon might not be extinct. Since scientists have, in the past, ultimately found living animals that were thought to be extinct, its a bit precocious to list the Discovery Channel Special as fiction. — Preceding unsigned comment added by 71.15.26.139 (talk) 15:42, 6 August 2013 (UTC)

The only problem is that the Discovery Channel's "documentary" is fake, all of the sightings shown are CG, all of the "scientists" are actors, and it even hid a 5 second disclaimer saying that the documentary was fake in the opening.--Mr Fink (talk) 15:55, 6 August 2013 (UTC)

linkage of Central American Seaway closure and extinction

The references cited do not support the claim that the worldwide extinction is attributable to the closure. Bruner (1997) simply mentions the closure without discussion. Domning (2001) in a discussion of regional extinctions, mentions the (regional) extinction of C. megalodon without comment, citing Allmon et al. (1996). Allmon et al. (1996), again talking about a regional extinction, simply say "The reasons for the disappearance of C. megalodon from Florida waters in the early portion of the Late Pliocene is unknown, but a contributing factor may have been a decrease in the abindance and diversity of large marine vertebrates..." WolfmanSF (talk) 08:00, 14 November 2011 (UTC)

Body mass formula or numbers are wrong !?

The proposed method is: mass in kilogram = 3.29E−06[TL in (meters)^3.174].[7] According to this model, a 15.9 metres (52 ft) long C. megalodon would have a body mass of about 47 metric tons (52 short tons). I read this as: m=3.29E-6*TL^3.174 m=3.29E-6*15.9^3.174 = 21.4g which is a tad bit off. Cannot check [7], which is also unlikely to contain the original research. — Preceding unsigned comment added by 193.170.138.132 (talk) 12:09, 15 December 2011 (UTC)

You're right. I'll just change the masses that claim to follow that model to the right numbers, and when someone has it figured out right, it can be changed later.Qwertzy (talk) 03:18, 2 February 2012 (UTC)

GA Reassessment

The following review has been postponed and is waiting for a copyedit by the GOCE. Please do not modify this review. Subsequent comments should be made in a new section on the Talk:Megalodon. No further edits should be made to this section until the copyedit is over.
This discussion is transcluded from Talk:Megalodon/GA2. The edit link for this section can be used to add comments to the reassessment.

Criteria

Good Article Status - Review Criteria
Further information: WP:WIAGA

A good article is—

  1. Well-written:
    2. (a) the prose is clear, concise, and understandable to an appropriately broad audience; spelling and grammar are correct; and
    (b) it complies with the Manual of Style guidelines for lead sections, layout, words to watch, fiction, and list incorporation.[1]
  2. Verifiable with no original research:
    3. (a) it contains a list of all references (sources of information), presented in accordance with the layout style guideline;
    (b) reliable sources are cited inline. All content that could reasonably be challenged, except for plot summaries and that which summarizes cited content elsewhere in the article, must be cited no later than the end of the paragraph (or line if the content is not in prose);[2] and
    (c) it contains no original research.
  3. Broad in its coverage:
    4. (a) it addresses the main aspects of the topic;[3] and
    (b) it stays focused on the topic without going into unnecessary detail (see summary style).
  4. Neutral: it represents viewpoints fairly and without editorial bias, giving due weight to each.
  5. Stable: it does not change significantly from day to day because of an ongoing edit war or content dispute.
    6. [4]
  6. Illustrated, if possible, by media such as images, video, or audio:
    7. [5]
    (a) media are tagged with their copyright statuses, and valid non-free use rationales are provided for non-free content; and
    (b) media are relevant to the topic, and have suitable captions.[6]

Review

  1. Well-written:
    2. Criteria Notes Result
    (a) (prose) No big issues, I have also requested a copyedit. Neutral Undetermined
    (b) (MoS) Some convert issues are not taken care of. Fail Fail
  2. Verifiable with no original research:
    3. Criteria Notes Result
    (a) (references) all fixed. Pass Pass
    (b) (citations to reliable sources) All reliable. Pass Pass
    (c) (original research) The reviewer has no notes here. Don't know Don't know
  3. Broad in its coverage:
    4. Criteria Notes Result
    (a) (major aspects) Covers em' well. Pass Pass
    (b) (focused) To the point, except for the anatomy section. Branches off to far in that section. Fail Fail
  4. Neutral: it represents viewpoints fairly and without editorial bias, giving due weight to each.
    5. Notes Result
    Pretty good. Pass Pass
  5. Stable: it does not change significantly from day to day because of an ongoing edit war or content dispute.
    6. Notes Result
    Pretty flat. Pass Pass
  6. Illustrated, if possible, by media such as images, video, or audio:
    7. Criteria Notes Result
    (a) (images are tagged and non-free images have fair use rationales) All fair. Pass Pass
    (b) (appropriate use with suitable captions) All fair. Pass Pass

Result

Result Notes
Neutral Undetermined I have noted about GAR on major contributors' talk pages. Allowing 2 days and then it will reach a decision.

Discussion

Please add any related discussion here.

References 42, 49, 59, 60 and 15 have been edited to resolve the issues raised in the GA reassessment review point 2(a). However, I don't know what the comment "There are also two external links" refers to. WolfmanSF (talk) 03:33, 19 August 2012 (UTC)
Sorry for not being descriptive enough on that. I am talking about 1. http://las.depaul.edu/env/People/KenshuShimada/ShimadaResearch/index.asp (info) [depaul.edu] and 2. A video clip depicting aggressive interspecific interactions between Megalodon and a pod of killer odontoceti (B. shigensis ) (info) [2hgs.com]. Both aren't cited right, and anyways they don't work. I have added more info above too. ObtundTalk 04:23, 19 August 2012 (UTC)
The dead external links have now been fixed. WolfmanSF (talk) 17:00, 19 August 2012 (UTC)
By the way, what is the problem with links that change their path? I have a hard time believing that http://www.google.com/books?id=2My8M5tL-KIC&printsec=frontcover#v=onepage&q&f=false would be preferred over the equivalent http://google.com/books?id=2My8M5tL-KIC&printsec=frontcover, for example. WolfmanSF (talk) 21:47, 19 August 2012 (UTC)
I have updated above. #64 changes and doesn't give any info. and #10 is still a dead link, ObtundTalk 23:00, 20 August 2012 (UTC)
The links in refs 10, 64 and 68 have been fixed. WolfmanSF (talk) 07:42, 21 August 2012 (UTC)
Regarding GA reassessment review point 1(b), I have edited a couple conversions, but I don't know which ones you object to. WolfmanSF (talk) 17:12, 19 August 2012 (UTC)
There's a few, if you just take a brief scan you'll find them all, if you want I can look again and note them for you. ObtundTalk 23:27, 19 August 2012 (UTC)
Regarding GA reassessment review point 3(b), concerning the "Anatomy" section, it would again be helpful to know where, in the reviewer's opinion, the text "branches off too far." In general, I don't understand the practice of suggesting that a problem exists and then being coy about what that problem is. WolfmanSF (talk) 15:59, 20 August 2012 (UTC)
An example would be in length estimates. Just make one subsection that has Methods and describe each you do not need to go too indepth you don't need a section for each Person, just summarize them in one. ObtundTalk 22:47, 20 August 2012 (UTC)
OK. Since this section is not my work, I'm going to let LeGenD or others decide if they see fit to follow up on your suggestion. WolfmanSF (talk) 22:57, 20 August 2012 (UTC)
However, given that the length estimation has been a problematic and controversial subject, as well as one of very great interest, I'm not convinced that your suggestion is really appropriate. WolfmanSF (talk) 15:27, 22 August 2012 (UTC)
The review above, has been postponed and is waiting for a copyedit by the GOCE. Please do not modify this review. Subsequent comments should be made in a new section on the Talk:Megalodon. No further edits should be made to this section until the copyedit is over.

Megalodon convert issues

Please specify any convert issues that remain in Megalodon. Thanks, WolfmanSF (talk) 19:59, 24 August 2012 (UTC)

Edit request on 29 August 2013

In Discovery -> Identification, pls change "On the basis of this observation, Agassiz assigned the genus Carcharodon to the megalodon" to "On the basis of this observation, Agassiz assigned megalodon to the genus Carcharodon", the new object being assigned to the existing category, rather than the other way around. Thx. 124.169.82.178 (talk) 03:32, 29 August 2013 (UTC)

Done.--Mr Fink (talk) 04:42, 29 August 2013 (UTC)
Thx! 124.169.82.178 (talk) 03:10, 30 August 2013 (UTC)

Fossil Vertebrae?

I am curious as to how vertebrae from this shark have been uncovered, when shark skeletons are made of cartilage and thus highly unlikely to fossilize. I'm not denying that such vertebrae have been found, but it must be a very unusual phenomenon indeed for cartilaginous matter to fossilize. --24.36.139.110 (talk) 00:58, 5 September 2013 (UTC)

Editing problems

The main article edit option is not working for me currently. New information for the subject is available but cannot be included in the article due to this reason. What is the issue? --LeGenD (talk) 05:32, 21 November 2013 (UTC)

It's semi-protected, due to persistent vandalism. Is that blocking you? WolfmanSF (talk) 21:37, 21 November 2013 (UTC)
Ok, I understand. Fortunately, I can now edit the main article.--LeGenD (talk) 07:05, 22 November 2013 (UTC)

Latest updates

Research on Megalodon have further progressed in recent times; more scientific papers have emerged in 2013. Scientific paper from Diedrich, in particular, is excellent, addresses some misconceptions, and offers a beautiful explanation of shark evolution since Eocene. These new scientific papers are now part of the references of the main article. Their is an upcoming scientific paper which delves deeper into the subject of extinction of Megalodon (seems to be a new theory); gigantism was an asset for Megalodon during ecological/environmental ground realities of Miocene but a drawback during ecological/environmental ground realities of Pliocene, specially after formation of Isthmus of Panama which facilitated decline in global marine productivity and natural cooling trends (I have access to some information of this paper but I have not used it as a source yet because the paper is pending publication which would happen in 2014). Also, some scientists have recently made presentations about rise and fall of prehistoric large sharks (including Megalodon); one is from Dr. Mike Siversson while another is from Dr. Bretton Kent; Dr. Mike Siversson explicitly disagrees with the speculation that raptorial delphinids have anything to do with extinction of Megalodon, and Dr. Bretton kent also mentions other reasons. Both presentations have been added in the external links section. Furthermore, here is a documentary which investigates the impact of formation of Isthmus of Panama on wildlife of Pliocene epoch: [Clash of the Americas]. I have implemented some changes in the main article on the basis of all of these updates. Input from fellow contributors is welcome.--LeGenD (talk) 07:05, 22 November 2013 (UTC)

Battlefield 4 Easter Egg Addition Proposition

I have a question: does it be relevant and not insulting to add the Battlefield 4 easter egg into the "in fiction" section? I did checked the edit history and talk page and not seen it be mentioned at all, so here is a background: There is an easter egg in Battlefield 4 where you can make the Megalodon to jump out of the water: https://www.youtube.com/watch?v=V-WladmrdNQ It is pretty cool and the video has over 3.25 million viewcount, but if you think that it should be added then go ahead. (I myself can't edit :)) Vulpecular (talk) 02:13, 6 June 2014 (UTC)

It does not appear to be very relevant. The "in fiction" should be about works of fiction that focus on Megalodon, and should avoid mentioning those works that simply have it as a "spot the monster" situation.--Mr Fink (talk) 02:27, 6 June 2014 (UTC)

Size and extinction date introduction

"Maximum size of 14-18 m ?"

14 m is not a figure provided in litterature, that's rather a guesswork from some wikiguy.

The appropriate statement, based on modern consensus and published data, should be stated as "maximum size up to 18 m".

Enough of these personnal guessworks while we have actual paper.

Update about the appearance and extinction dates are needed. An appearance 28 millions years ago is highly discutable and is only known from a New Zealand example. Presumably, the 28 M old dated tooth has been displaced in older deposits and was much more recent. See Pimiento 2014.

Pimiento 2014 has updated too the final extinction date at 2.6 millions years ago, not 1.5 millions.

Article needs updates on these points. — Preceding unsigned comment added by Over there (talk • contribs) 00:30, 11 November 2014 (UTC)

Too many subsections

This article has a section for nearly every paragraph, which is rather ridiculous. Most of the headings should simply be removed. FunkMonk (talk) 17:10, 30 November 2014 (UTC)

I noticed this as well some time ago, but I didn't saw what's wrong with it. Anyway, I started removing some headings (but only a few because I want to see what other people think about that). Jinfengopteryx (talk) 22:04, 1 December 2014 (UTC)

Split off Carcharocles

Since there are several other species of Carcharocles, wouldn't it be prudent to eventually split it off as its own article?--Mr Fink (talk) 16:53, 29 July 2015 (UTC)

Yes, obviously. FunkMonk (talk) 16:54, 29 July 2015 (UTC)
I definitely think we should. IJReid discuss 18:31, 29 July 2015 (UTC)

The Asylum 4 films

  1. Mega Shark Versus Giant Octopus
  2. Mega Shark Versus Crocosaurus
  3. Mega Shark Versus Mecha Shark
  4. Mega Shark Versus Kolossus

We should mention these as how the Megalodon has had influence on pop culture. The sharks in these films are specifically called Megalodons in the film, just not the title. These are the guys who made the 3 popular Sharknado films. 64.228.91.73 (talk) 00:28, 15 August 2015 (UTC)

And how have these particular movies influenced the way popular culture views Megalodon? Simply because the topic of the article is the star of a bunch of B-monster movies does not necessarily mean aforementioned movies are important enough to merit discussion.--Mr Fink (talk) 00:33, 15 August 2015 (UTC)

Megalodon Size

How exactly is Megalodn's mass determined? The reason I ask is because some calculations I did seem to get different figures. Using the square cube law and comparing Megalodon to the largest Great White sharks, as most people do. The largest Great Whites were almost 7 metres and alomost 4 tonnes. Taking the 14 metre Megalodon estimates and using the square cube law, a 14 metre Meg would have been about 8 times as heavy as a 7 metre Great White. So about 30-35 tonnes. Of course a 15 metre Meg, which is the average estimation, would have been heavier. It also assumes Meg having similar proportions to Great Whites, when some think it slimmer and others the opposite. But I still find it hard to believe the weight exceeding 40 tonnes despite these allowances. Again huge estimates of 18 metres would be considerably higher, but for the more reliable 15 metres is this calculation correct or accurate? If not could someone explain the errors in it and how the weight of sharks are determined? 112.134.231.137 (talk) 17:56, 26 December 2015 (UTC)

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