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Post by elosha11 on Jun 13, 2013 2:01:09 GMT 5
Great pics, thanks!
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Post by Grey on Jun 13, 2013 3:06:24 GMT 5
I will delete the first pic with the seemingly 8 inches tooth. Ive got informations from Steve Alter. The tooth was from MegMawl and heavily reconstructed from two fragments.
Cannot be used as reliable.
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Post by elosha11 on Jun 15, 2013 6:24:21 GMT 5
That's too bad. It would have been of record length.
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Post by Life on Jun 15, 2013 11:42:09 GMT 5
Largest Megalodon tooth yet found is 7.62 inch long; it was found by Vito Bertucci and he used it in one of his jaw reconstructions.
One more thing: Restoration is not always about size. Fossil teeth are sometimes restored to bring them to their original shape from deformed shape.
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Post by Grey on Jun 15, 2013 11:46:40 GMT 5
But according to Steve Alter, this one was partly reconstructed. Which does not mean its actual size was not approximatively that big.
Even Hubbell's tooth is slightly restored according to him, even though for discussing with Ehret and Siversson they consider that one as scientifically reliable.
Brett Kent wrote me that the giant Chilean tooth he saw but did not measure would certainly approach 20 cm. It barely fit in a cigar box ad he said.
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Post by Life on Jun 15, 2013 11:57:45 GMT 5
But according to Steve Alter, this one was partly reconstructed. Which does not mean its actual size was not approximatively that big. Yes, Meg MawL's largest specimen is heavily restored. Even Hubbell's tooth is slightly restored according to him, even though for discussing with Ehret and Siversson they consider that one as scientifically reliable. It is "absolutely" reliable tooth because its size is original. Even the largest tooth in possession of Steve Alter is slightly restored but its size is original. Restoration is not about size only. Its main purpose is to bring a fossil tooth to its original form. Brett Kent wrote me that the giant Chilean tooth he saw but did not measure would certainly approach 20 cm. It barely fit in a cigar box ad he said. Very impressive. |
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Post by Grey on Jun 15, 2013 12:02:19 GMT 5
I was talking about Vito's tooth bro ! The 7.62 incher was restored, at which point I don't know. But seems like they were of great quality.
Alter praised Vito's work about the giants jaws by the way, even if they could be less stretched and reduced of one foot in size.
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Post by Life on Jun 15, 2013 12:05:06 GMT 5
I was talking about Vito's tooth bro ! The 7.62 incher was restored, at which point I don't know. But seems like they were of great quality. Alter praised Vito's work about the giants jaws by the way, even if they could be less stretched and reduced of one foot in size. Even it is restored, it is asinine to assume that its size is fake without solid reasons. Steve Alter has a habit of promoting largest Megalodon tooth in his possession as genuine and others not; I dislike this mindset. |
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Post by Grey on Jun 15, 2013 12:12:55 GMT 5
Certainly. In fact the debate of which tooth is the largest in the world is often discussed and not yet conclusive.
If the restoration is good, the 7.62 incher is the largest. Which would be its width ?
It appears large UA are almost always narrower than the Laterals.
The Chilean 18.5 cm "devilish" specimen is problematic as its root is unusually long.
Here again I wonder of its width. Contrary to fossils hunters I'm more interested into the width than the length !
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Post by Life on Jun 15, 2013 12:23:38 GMT 5
Certainly. In fact the debate of which tooth is the largest in the world is often discussed and not yet conclusive. Agreed here. If the restoration is good, the 7.62 incher is the largest. Which would be its width ? Slant height. This tooth is embedded in this jaw reconstruction: www.thehistoryblog.com/wp-content/uploads/2011/03/largest-Megalodon-jaw-fossil.jpgUpper Anterior tooth on the right seems to be the one. Supposed restoration is fine. Fossil teeth are restored by experts. It appears large UA are almost always narrower than the Laterals. Not necessarily. The Chilean 18.5 cm "devilish" specimen is problematic as its root is unusually long. This is false alarm. Megalodon teeth have very big roots and root size is variable. Just look at the root sizes of teeth in the Megalodon reconstruction above to get an idea. Here again I wonder of its width. Contrary to fossils hunters I'm more interested into the width than the length ! The largest teeth in the aforementioned jaw reconstruction are also very wide. --- I assume that you had a discussion with Steve Alter on this subject. I advice you to not put too much faith on his claims. He is more of a business man then an expert. |
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Post by Grey on Jun 15, 2013 12:32:49 GMT 5
About the lateral wider than the upper, this is a quote from Alter. I should ask directly to fossils sharks experts perhaps.
I had the read on the fossil forum than the "devilish" tooth was a pathological, but not sure there too. Pete Larson did not give responses.
Stomatopod expected a tooth like the largest by Bertucci to be 14,2-15,2 cm wide...
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Post by Grey on Jun 16, 2013 10:12:19 GMT 5
Opinion of Mike Siversson regarding the doubts by Brett Kent about megalodon reaching 20 m. 
If we did not have giraffes I am sure people would argue that it could not possibly work have such a tall neck given the very high blood pressure needed to pump blood all the way to the head. There are numerous circulatory novelties in giraffes that enable them to function in spite of exhibiting an ‘impossibly’ tall neck. Nature tends to find a way around physiological constraints. In the case of C. megalodon the dentition indicates TL’s approaching 20 metres. One could of course imagine C. megalodon equipped with a disproportionally wide head. I agree with some of Bretton’s speculations (eg that Parotodus is unlikely to have been a giant thresher sharks as it would indicate tip of the tail velocities exceeding the speed of sound) but I respectfully disagree with him regarding megalodon. The teeth are real and they are huge, there is no speculation there. Do you renember the paper that I showed you on Facebook quite a while ago? And why I did comment on it? We know nothing about the cardiovascular system, but given its evolutionary history it was probably quite derived compared to the ones seen in other sharks. Maybe someone will find a fossilized meg heart one day. You know who already did find a fossilized Kentriodon brain  Might also interest others: www.escholarship.org/uc/item/2t8325zp#page-3 . Read the paper starting at page 73. Or even better, read all if you are interested in sharks ;-) I've realized that Kent actually refers to this in his incoming chapter about meg :
While these allow for higher activity
levels in extant lamnids, such as the shortfin mako (I. oxyrinchus) and great white shark (C.
carcharias), that reach maximum sizes of about 6 m, itÂ’s unclear whether they would be
adequate for a truly gigantic, fast-swimming shark of about 20 m.I've sent him a mail about the question. Why meg wouldn't have evolved itself a specific adaptation already since it evolved at a very different scale than these two modern species which are from various viewpoints the closest in their lifestyle to meg. |
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Post by Grey on Jun 17, 2013 11:35:01 GMT 5
Megalodon tooth specimen from Morgan River. 17,2 cm in slant height, 12,7 cm in width.  Body size estimates : Extrapolation of Megatooth Total Length From Regression of White Shark Tooth Height Versus Body Size (Gottfried) : 16,29 m conservative TL. Direct Sizing of Megatooth Sharks from White Shark Teeth (Gottfried) : 18,65 m TL (based on 6,4 m CUBA white shark), 20,69 m TL ? (based on 7,1 m MALTA white shark). Root width method (Jeremiah) : 17,41 m TL. |
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Post by Grey on Jun 21, 2013 21:41:57 GMT 5
  Cannot see the exact length in cm, in excess of 7 inches. Approx. 13,5 cm wide. If Jeremiah's is valid, about 18,5 m TL.  Peruvian specimen. Unknown measurements. |
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Post by theropod on Jun 21, 2013 21:52:04 GMT 5
Based on the scale it is 17,67cm long in maximum lenght, 14,37 in medial lenght and 13,1cm in maximum width. There might be slight perspective involved, but not significantly, the centimetres are all the same lenght.
How exactly are the measurements taken (eg. slant height), and is there any publication or demonstration to look such things up?
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