Talk:Spinosaurus

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Archive 1 (February 2006 - September, 2006)

JP3

Just to let everyone know that I have added one of those invisible requests that can only be seen when you try to edit the section (cant remember the proper name at the moment) to the JP3 section, seeing as the old "the Rex should have won" debate seems to be rearing it's ugly head again. Hopefully that might help. Regards.SMegatron 12:31, 9 November 2006 (UTC)

Size?

According to this [[1]] and this [[2]], the size of spinosaurus is overexaggerated. The only evidence, according to this source and various others, for an 80 foot long spinosaurus is from an 8-foot long skull, which could belong to something else. Also, as mentioned in the first source, Half of Spinosaurus's length was its tail. Really, I think this should be taken into consideration. The article makes it sound like a whale. Any thoughts?--DeadGuy 17:34, 11 November 2006 (UTC)

I can't think of a way this could possibly be more false. The tail of Spinosaurus has never even been found, and the tails of baryonychines are roughly the same proportions as in other theropods. Same for Allosaurus. The extremely long tails illustrated on that site are hilarious. In fact, the (normally proportioned) skeletal diagram in the second link directly contradicts this idea and proves the tail to be conjectural.Dinoguy2 21:33, 11 November 2006 (UTC)

From the second link: "A large Spinosaurus skull, rumoured to be eight feet long, has turned up more recently. If the measurement is correct, this would suggest that the complete animal was longer than any known Giganotosaurus or T. rex, but there are no reliable sources yet." This is the skull described by dal Sasso. The site is out of date.Dinoguy2 21:33, 11 November 2006 (UTC)

I can only agree with Dinoguy; no site which illustrates theropod tails that long can be taken seriously. The Allosaurus and Spinosaurus illustrated there are extremely ridiculous, and the last four theropod illistrations look like they are about to topple over! I'll also note the incorrect hand position on nearly every one of those illustrations. This is not a reputable (or remotely believeable) source. Let's stick with published papers, if possible. Firsfron of Ronchester 23:10, 11 November 2006 (UTC)

Sorry this may come of as an angry lecture it isn’t meant to be. Also I’m not very good at getting my thoughts on to the page, so it may not make sense. Why do people keep constantly changing this article. Why do they feel the need to change the size estimates, do they just get board of the old ones. What was wrong with the dal Sasso estimates, the dorsal vertebra of the holotype ranged from 19 to 21cm in length. The 21 cm vertebra, I think belongs near the sacral region were the dorsals are at their largest. The 19 cm vertebra was probably located between the middle dorsal region and the cervical vertebra. What this shows is that the vertebra aren’t going to be much bigger than the 21 cm and on average will be smaller. Assuming that on average the vertebra were 20 cm, (the average will probably be smaller) and that there’s about 19 to 20 dorsal+sacral vertebra then that whole region will be around 4m. Then you add the head which is estimated at 1.45m and the neck which is probably a similar length, you get nearly 7 m from the snout to the back of the hip. The tail is most probably half or more the total body length which gives the holotype a length roughly around 14m in length. Then direct scaling form the 998cm snout you get an animal around 16-17 m in length. In no way can I get 17.4m for the holotype, even though the vertebra are almost twice the size of baryonyx walkeri (the largest being 11cm ). Also has any one tried to draw it, it looks ridiculous as well. Also I am not sure but isn’t the fragmentary snout from MNHN SAM 124 comparable in size to MSNM V4047, I could be wrong. thanks. steceoc_86

If you manage to publish the above in a peer-reviewd journal, or provide us with a published citation that repeats this information, then it can be included. As of right now, dal Sasso is just about the only current published source on this topic, and so it's the "official" last word.Dinoguy2 13:48, 19 November 2006 (UTC)

• thanks for the reply. I may have confused you, I was ‘agreeing’ with the dal Sasso estimate, I wasn’t agreeing with the 17.4m holotype estimates. Thanks Steveoc_86 19 November 2006

Ah, I see. My bad. I'm so used to defending the dal Sasso size, this sort of thing has become a reflex ;)Dinoguy2 21:45, 19 November 2006 (UTC)

Who changed the estimate for MSNM V4047 (the del sasso skull) to 13m, thats the one he estimated between 16-18m with a skull about 1.75m. if it was the comment about MNHN SAM 124 'Possibly' being comarible in size to the del sasso skull, i saw a skeletel drawing by scott hartman in which he used SAM 124. i got the impression he scalled the holotype material to it. Other than that i have no idea how large MNHN SAM 124 is. I prefere the other estimates though. steveoc_86 21 november 06

Im really confused... i looked at the spinosaurus page and the estimated were all different like the holotype being 15m, i write the paragraph above, i go back and the estimates are back to normal? what happend???? im so confused. :0 Steveoc_86 21 nov 06

People frequently alter this article with false or outdated information. With luck, it is quickly corrected.Dinoguy2 01:28, 23 November 2006 (UTC)

Regarding your objections to Mortimer's 17.4 m estimate for the holotype, I think I might perhaps make it more acceptable to you. Firstly your neck estimate is a bit on the low side. The problem with the holotype is precisely that the skull seems to be rather small for the rest of the body. Should they belong together however, the total neck-skull length would, when using Baryonyx as a model and bringing the dimensions of the neck in proportion to the thorax instead of the skull, be above 3.5 m, perhaps approaching 4 m. This is in a stretched position; Spinosaurus might obviously habitually have held it in a strong S-curve. So we now have a total length of about 15-16 m. Secondly the estimate includes the intervertebral discs, giving it an extra 10% or so. This would bring total length to 16.5-17.6 m.--MWAK 16:35, 1 December 2006 (UTC)

Interesting, I hadn’t thought of the discs. It would be nice to know how much cartilage is actually needed based on other animals. Scaling a Scott Hartman skeletal drawing of Baryonyx Walkeri to have ‘approximately’ a 21cm vertebra (were that vertebra is thought to have come from) gives an animal closer to the dal Sasso estimate. My neck estimate was based of doing that, its not the most scientific method. He draws the arms further down the body than in other reconstructions giving the illusion of a longer neck, I’m specifically counting cervical vertebra. Also I think other spinosaur reconstructions show their neck ‘approximately’ being similar in length to the head. I still think that 17m for the holotype seems a bit big, how long a tail is Mortimer giving it. I've read Mortimer's posts on the 'Dino mailing list' he seems to be good with measurments. Oh well, who knows I'm probably wrong. As rational scientifically minded people lets pray to the Dinosaur God that a complete spinosaurus skeleton will be found to resolve this. Amen. :) thanks Steveoc_86 02 December 2006

I’ve just quickly tried to draw it with a longer neck and it still looks wrong to me. I’ve also checked the measurements that are on Stromers’ paper. The two cervical vertebra in the paper included the first cervical (that joins the skull) (which had no measurement in length but looks shorter than the second) and the second was 18.5cm and I'm not sure were that goes. Scaling a complete baryonyx drawing the vertebra can fit nicely in place of any of the last four cervicals. How many cervicals have you given it? I think theres 8. It would be nice if someone could tell me (based of bary suchomimus, and other relatives) how many vertebra generally there should be in each region of its body (cervical, dorasl, sacral, caudal). The problem I get with the 17.4 holotype is that for me, even with 10% extra for discs, it requires extra vertebra. Also it is such a specific measurement and spinosaur tails are fragmentry. You have succeeded in lengthing it for me a bit, a 'little' closer to 15m. Thanks steveoc_86 21:34 02 December 2006

Well, there are nine cervicals, fourteen dorsals and five sacrals. Indeed the first cervical is very short. However, confusingly, the first dorsal is really part of the neck (Gregory S. Paul always used to maintain that, ergo, it really was a cervical :o), so we still have to count nine vertebrae to estimate neck length. You have probably included two caudals between the posterior ilium blades in your count of twenty for the "trunk" length. Now it is very, very tricky to estimate the length of the cervicals extrapolating from that of the dorsals. Some theropods have very short cervicals, others very long ones. It seems however that having rather long cervicals is the "primitive" state for Tetanurae, and the fact the second cervical has a length of 18.5 cm seems to confirm Spinosaurus wasn't much derived on this point: it indicates the longest cervicals would be well over 25 cm. Taking a conservative 22.5 cm as an average for the nine vertebrae determining neck length, we get, including the first cervical, about 3.6 m for the head-neck total; 7.6 m adding the twenty vertebrae up till the point of the ischium; 15.2 metres for total axial bone length; 16.7 metres adding the intervertebral discs. Keep in mind that, when looking at a drawing, the curvature would make the neck seem shorter. Using pieces of string to measure the real length is always advisable. —The preceding unsigned comment was added by MWAK (talk • contribs) 08:55, 3 December 2006 (UTC).

Are you placing the 18.5 vertebra as the second cervical? Is it acually known to have come from there? Again I'm useing direct scaling from baryonyx, which isn't perfect i know, but that vertebra can fit in so many places and not increase its neck length much. Could you give some exarmples of the primtive Tetanurae that your thinking of. i want to upload a drawing to demonstrate, its far from perfect but i hope it will give an idea of what im getting at, even if im wrong. Im trying to get permision from Scott Hartman site to use their baryonyx. thanks Steveoc_86 12:43 3 December 2006 —The preceding unsigned comment was added by Steveoc 86 (talk • contribs) 12:45, 3 December 2006 (UTC).

ive change my mind i can't be bothered to put an image up its too complicated. :) Steveoc 86 13:44, 3 December 2006 (UTC)

Consulting Stromer made it clear to me my memory failed me: what you called the first cervical is the second and the other cervical Stromer indicated as the sixth. Even though the four more posterior vertebrae would be probably a lot bigger, this brings down the head-neck estimate quite a bit, to a probable 3.2 - 3.3 m. Total length would still be 15.8 - 16 metres, but I have to admit this is a serious change :o). However Markgraf apparently didn't provide any data considering the exact position the rather damaged fragments were found in, so any identification is tenuous. --MWAK 09:24, 4 December 2006 (UTC)

I just read that CMN 50791, the holotype of S. maroccanus, consists of a 195 mm mid-cervical. Giving "primitive" Tetanurae to compare spinosaurids against is rather difficult as they might themselves well be derived from the most basal known split within Tetanurae :o). It's just that all neotheropod small forms don't have the relatively short cervicals of e.g. T. rex.--MWAK 13:19, 4 December 2006 (UTC)

I also took a closer look on the drawings of Hartmann. It seems to me the reason why his Baryonyx is so large in comparison to his Spinosaurus lies in two facts: firstly the way he draws the vertebrae gives a 25% extra for the intervertebral discs for the smaller species, but a shorter ratio for the larger; secondly the trunk section of his Spinosaurus is too short: the last vertebra he illustrates is the 16th so the tail base should only begin two or three more vertebral lengths to the right. As the tail section is kept in proportion, this mistake alone reduces total lenght by 1-1.5 m. If you limit yourself to a 10% intervertebral disc ratio, Baryonyx is merely about eight metres long. This explains why Mortimer has such a high estimation as he based himself on the common 9-9.5 m estimate for Baryonyx. His 17.4 m estimate is simply 14.5 m axial column bone length plus 20% for the intervertebral discs. I should have understood that earlier :oS.--MWAK 11:02, 5 December 2006 (UTC)

When i emailed him he said he'd get wrking on an update with the new skull material. I asked about the number of vertebra he used in a seconed email and i haven't got a reply yet. Thats why i didn't want to use it. Overall i feel the best reconstruction to date is the del Sasso one, he doesn't give a really specific measurement. Are you shure that stromer thought the vertebra i called the first was the second (c2)? Were does he say that? Interesting what you say about baryonyx. I got a similar arnswer when did my dodgy maths technique on it(like what i used above in my initial spinosaurus rant :). I had thoutht that Mortimer might have done somthing thing like that. Its quite usful that the spinosaur holotype is nearly twice the size of baryonyx as it keeps things reasonably simple. I know that baryonyx and sucho are not its 'closest' known reletives, but they are its closest 'resonably complete' reletives, so i'd rather use them as comparison.I also know that skeletal drawings arn't perfect but its the best i can do. thanks Steveoc 86 12:02, 5 December 2006 (UTC)

The Dal Sasso paper is very careful in not making any claims that can't be substantiated. It's always best to err on the side of caution. As regards the cervical number, keep in mind the first cervical is the atlas!--MWAK 14:33, 6 December 2006 (UTC)

isn't there a living reptile with a sailback?

I think that there's a living reptile with a smaller sail back, I do not know if also made of vertebral extensions, but perhaps it would be could be mentioned if someone knows which animal is it and it would really serve as an example of something. I think it is one lizard of galapagos, but could be from anywere really. I think it resembled a bit more the sail of sailfishes, however. --Extremophile 05:38, 4 December 2006 (UTC)

Perhaps you mean the Sailfin lizard; the Marine iguana would be the Galápagos one, but he hasn't got a real sail. It could of course serve as an example of a sail, but such references are a bit confusing. I personally feel it would be best to avoid suggesting any strong connection between dinosaurs and lizards :o).--MWAK 09:15, 4 December 2006 (UTC)

At least one paper has pointed out that the best modern comparison for a Spinosaurus sail are the tall, "sail"-like vertebrae of buffalo and other bovids [3].Dinoguy2 14:02, 4 December 2006 (UTC)

proof

Would someone please give me some god damn proof about spinosaurus being 16-20ft. And please give me proof before you revert it. I say if there isn't any proof for spinosaurus being 16-20ft, We might as well put it at 16-22ft in height or randomly puting it a unreasonable 30ft tall. My point is PLEASE PUT SOME PROOF IN THE ARTICLE! —The preceding unsigned comment was added by 69.23.65.113 (talk) 21:12, 5 December 2006 (UTC).

The "proof" is already in the article, and has been there for some time. At the bottom, where it says "References", is dal Sasso, C., S. Maganuco, E. Buffetaut and M. A. Mendez (2006). "New information on the skull of the enigmatic theropod Spinosaurus, with remarks on its sizes and affinities.". Journal of Vertebrate Paleontology 25(4): 888-896. Firsfron of Ronchester 03:34, 6 December 2006 (UTC)

Thats hardly proof for the height of the animal (And might I add was it realy neccesary to block me from editing? I put down information on a page that is just as likly as the previous info and I get blocked for it. Next time how about a warning insted of being selfish and block me from editing.) 69.23.65.113 21:13, 8 December 2006 (UTC)