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Post by Grey on Jun 21, 2013 22:00:11 GMT 5
So, based on Jeremiah : 18 m TL.
Based on Gottfried's extrapolation : 16,8 m TL.
Based on direct sizing : 19,2 m TL; 21,3 (?) m TL.
I'd like to know how to use Shimada's allometry.
I've seen technic of measurements on some fossils collectors forums.
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Post by theropod on Jun 21, 2013 22:31:01 GMT 5
Grey: Measuring it is a bit tricky, the resulutions would have to be higher to do it precisely. The tooth in its maximum lenght (that seems to be slant lenght from what I saw) is 530px One inch is about 75px, and one centimetre 29-30px. Neither fits the translation perfectly, but 17,78cm seems possible too You'd better just measure it yourself.
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Post by Grey on Jun 21, 2013 23:20:41 GMT 5
If it is exactly 7 inches, what seems likely viewing the pic.
Extrapolation by Gottfried : 16,9 m TL.
Direct sizing : 19,3 m TL; 21,4 m TL.
Not a great difference...
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Post by Grey on Jun 22, 2013 20:10:38 GMT 5
 Dominican Republic partial tooth. Can someone accurately determine its width ?  Also curious to know the width of the large tooth (upper Lateral I guess ?) owned by Ehret here. |
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Post by creature386 on Jun 22, 2013 22:24:45 GMT 5
I got a width of 10,625 cm for the upper tooth and using the width method, I got ~13,3 m for the TL of the owner.
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Post by theropod on Jun 22, 2013 22:36:23 GMT 5
Seems rather 11,4 to me (648/67px) Grey: Just wondering, could you include a references-section (links) in the opening post please, since you are basing a whole thread full of size estimates on it? And I'd be interested in that supposed giant 7,2m Great white, were was it reported? The "direct sizing" seems to produce overestimates, at least based on this: books.google.at/books?id=2My8M5tL-KIC&pg=PA60&lpg=PA60&dq=great+white+tooth+length+total+length&source=bl&ots=3qkJ367cpS&sig=hRdXM1ExDKyaDKh9G0BTGAcCACk&hl=en&sa=X&ei=rODFUczRHY2Wswbl4oHIAg&redir_esc=y#v=onepage&q=great%20white%20tooth%20length%20total%20length&f=falseReporting 10 large female great whites to have an average tooth height (Upper anterior 2) of 5,92cm and an average TL of 5,5m. This has a 5 times larger sample and should be more realistic. Using the largest tooth this would yield a lenght close to 18m, and for the uften-used 16,8cm one it yields 15,6m. |
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Post by creature386 on Jun 22, 2013 22:39:17 GMT 5
I did not measure the pixels, so yours is probably more realistic.
Anyway, this would yield a length above 14 m.
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Post by Grey on Jun 22, 2013 22:41:17 GMT 5
Seems rather 11,4 to me (648/67px) Grey: Just wondering, youd you include a references-section (links) in the opening post please, since you are basing a whole thread full of size estimates on it? And I'd be interested in that supposed giant 7,2m Great white, were was it reported? References for ? That 7,1 m ? great white is the famous MALTA individual, discussed in a recent paper addition in the great white profile thread. If the tooth is 11,4 cm TW, we get theoretically a 15,6 m TL meg. Any idea about the tooth of Dana Ehret ? |
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Post by Grey on Jun 22, 2013 22:42:33 GMT 5
I did not measure the pixels, so yours is probably more realistic. Anyway, this would yield a length above 14 m. Are you sure you perform the good calculation ? Jeremiah is : 1 cm of tooth width= 4,5 feet(1,37 m). |
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Post by theropod on Jun 22, 2013 22:42:43 GMT 5
References for the metods, for the specimens etc.
btw see my edit regarding the direct sizing.
EDIT: and a more detailed description of the respective method may be a good idea too, not?
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Post by creature386 on Jun 22, 2013 22:43:57 GMT 5
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Post by Grey on Jun 22, 2013 22:45:24 GMT 5
Seems rather 11,4 to me (648/67px) Grey: Just wondering, could you include a references-section (links) in the opening post please, since you are basing a whole thread full of size estimates on it? And I'd be interested in that supposed giant 7,2m Great white, were was it reported? The "direct sizing" seems to produce overestimates, at least based on this: books.google.at/books?id=2My8M5tL-KIC&pg=PA60&lpg=PA60&dq=great+white+tooth+length+total+length&source=bl&ots=3qkJ367cpS&sig=hRdXM1ExDKyaDKh9G0BTGAcCACk&hl=en&sa=X&ei=rODFUczRHY2Wswbl4oHIAg&redir_esc=y#v=onepage&q=great%20white%20tooth%20length%20total%20length&f=falseReporting 10 large female great whites to have an average tooth height (Upper anterior 2) of 5,92cm and an average TL of 5,5m. This has a 5 times larger sample and should be more realistic. Using the largest tooth this would yield a lenght close to 18m, and for the uften-used 16,8cm one it yields 15,6m. This is nowhere stated as an overestimate but the most simple non conservative method of sizing. The references are in the name of methods in the first post of the thread. |
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Post by creature386 on Jun 22, 2013 22:45:49 GMT 5
I did not measure the pixels, so yours is probably more realistic. Anyway, this would yield a length above 14 m. Are you sure you perform the good calculation ? Jeremiah is : 1 cm of tooth width= 4,5 feet(1,37 m). I used the one here:  I took the largest (2 inch=250 inch or 1 cm =1,25 m). |
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Post by Grey on Jun 22, 2013 22:48:26 GMT 5
Are you sure you perform the good calculation ? Jeremiah is : 1 cm of tooth width= 4,5 feet(1,37 m). I used the one here: I took the largest (2 inch=250 inch or 1 cm =1,25 m). Sounds strange because this is the Jeremiah's method used for the meg exhibit. The exact calculation is 1,37 m (4,5 feet) for 1 cm of tooth width. |
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Post by creature386 on Jun 22, 2013 22:49:48 GMT 5
I now get ~15,6 m. This is a really huge specimen.
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