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Post by theropod on Dec 15, 2019 5:55:52 GMT 5
Yes, to do bone histology you need destructive sampling of some kind. Not necessarily cutting out an entire slice, but at least core drilling or grinding down a fragment that has broken off. Non-destructive methods simply cannot manage the necessary resolution (or contrast, probably) as this is on the scale of individual bone cells (and we are talking about solid, mineralized bones).
Also, we need light miscroscopy because we want to be able to use polarized light to help discern structures, which we obviously couldn't do from micro-ct or synchrotron scans even if they had sufficient resolution.
So sadly, nope, we cannot use Ct for this.
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Post by spartan on Dec 16, 2019 15:00:21 GMT 5
A very ironic post, considering it comes from the person who considers a 15t Triceratops to be realistic based on known fossils.
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Post by dinosauria101 on Dec 16, 2019 16:06:01 GMT 5
I didn't say 15 tonnes was guaranteed. I said it was possibly on the table.
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Post by spartan on Dec 16, 2019 17:10:25 GMT 5
Can you really not see the massive bias in citing a very conservative 6.3 tonnes as the average for an adult T. rex, but at the same time being so liberal with Triceratops that you consider 15t to be possible based on an obscure reconstruction nobody even knows the methodology behind?
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Post by dinosauria101 on Dec 16, 2019 17:15:52 GMT 5
Look. All I said was that 15 tonnes was POSSIBLE based on 1 reconstruction.
It is not guaranteed whatsoever and it could just as easily be 11-13 tonnes. I fully acknowledge that.
All I am saying is 15 tonnes is on the table. Not set in stone or guaranteed, it could very well be that the 11-13 tonnes is better.
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Post by spartan on Dec 16, 2019 17:26:01 GMT 5
It could also very well be that 9-11t is the most reasonable estimate for the maximum Triceratops. Why are you not mentioning that one?
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Post by dinosauria101 on Dec 16, 2019 17:27:20 GMT 5
I don't trust GSP's skeletals for Triceratops. They're often composites with many specimens (exactly which aren't mentioned), nor is it mentioned if ANY cross scaling was done between specimens. Broly made a good point about it, I'll get the quote.
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Post by creature386 on Dec 16, 2019 17:45:46 GMT 5
I've just moved a little discussion here, but I might need to bump the thread so that people see.
Spartan, if you were planning a reply to Dinosauria, post it here.
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Post by spartan on Dec 17, 2019 20:51:12 GMT 5
I don't trust GSP's skeletals for Triceratops. They're often composites with many specimens (exactly which aren't mentioned), nor is it mentioned if ANY cross scaling was done between specimens. Broly made a good point about it, I'll get the quote. So because you deem Greg Paul's reconstructions as inaccurate you rather use one where you don't know the methodology behind and that yields 15t monsters? And even aside from Greg Paul, the largest specimen based on Scott Hartman's skeletal also does not even reach 11t. |
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Post by dinosauria101 on Dec 17, 2019 20:54:46 GMT 5
I don't trust GSP's skeletals for Triceratops. They're often composites with many specimens (exactly which aren't mentioned), nor is it mentioned if ANY cross scaling was done between specimens. Broly made a good point about it, I'll get the quote. 1: So because you deem Greg Paul's reconstructions as inaccurate you rather use one where you don't know the methodology behind and that yields 15t monsters? 2: And even aside from Greg Paul, the largest specimen based on Scott Hartman's skeletal also does not even reach 11t. 1: The methodology was a GDI. Didn't I link it earlier? 2: Nowhere did I deny that |
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Post by dinosauria101 on Dec 20, 2019 17:09:18 GMT 5
Okay, this may have some SIGNIFICANT implications on what we know about the mass of Triceratops.
Apparently, Greg Paul's top view is faaar too thin - SIW for instance scaled it to 8 meters and it was 24 cm narrower than the measured ribcage width (185 cm) of Kelsey, a 6-7 meter specimen. This probably means even GetAwayTrike's skeletal may be underestimated, and probably to a greater degree than what SpinoInWonderland predicted. Note that I am NOT saying Triceratops was guaranteed to reach sizes in excess of 13-14 tonnes on a regular basis due to this. Just that it may have some implications and effects on what we think we know about the mass of Triceratops.
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Post by dinosauria101 on Jan 3, 2020 18:43:27 GMT 5
(Last post on Trike's size here by me, I promise! This is after re-examining the measurements and GDI's a few times) As was previously stated, the earlier GDI ( link)* gives a Triceratops with a 2.5 meter skull and total length of 8.26 meters a mass of about 10.5 tonnes, and I'd in fact argue it would be closer to 11 tonnes given that the parts of the head in red are excluded and that there is very little soft tissue on the legs, tail, and chest, as I did earlier. And that's not the biggest Trike - the largest specimens would have skulls of 2.7 meters. Scaling to this increases mass by about 26%, and thus scaling that Triceratops to specimens such as AMNH 5040 and UCMP 128561 gives a mass of 13.85 tonnes when scaled from a more realistic weight of 11 tonnes from the hyperlinked GDI. HOWEVER, these mass estimates are still probably undersized at least a little bit. The width of the top view of the hyperlinked GDI is about 3/4 of the length of the skull, which would give us about ~185 cm width for the top view. The thing is, a smaller specimen of Triceratops called Kelsey, at 6-7 meters, is also 185 cm wide in top view ( link). Thus, this 8.26 meter Triceratops has the width of a 6-7 meter one and is therefore almost certainly underestimated in terms of mass. If we choose to go by direct scaling from Kelsey, this specimen would have a width of about 235 cm top view, and is probably undersized width wise at 11 tonnes by about 27 percent. As for the largest Triceratops specimens, the same would apply; they are just under 200 cm (199.8) wide directly scaling from the GDI as-is, but this also appears to be an underestimate as scaling from Kelsey would give us about 253 cm for the top view-width of these specimens. Note that this is by no means to be taken as 100% factual or set in stone whatsoever as it is, just like every other mass estimate for every extinct animal, an educated guess. However, it is entirely possible and on the table that the largest specimens of Triceratops could have exceeded 13.85 tonnes quite substantially, and even smaller ones could well have been over 11 tonnes by quite a bit. In regards to more average sized specimens, scaling down from an 11 tonne specimen with a 2.5 meter skull gives ~8.23 tonnes for a Triceratops with a 227 cm skull if we choose to trust theropod on that being average. However, the width of the 8.23 tonne specimen would have still been undersized by about 27%, as per what I went over above. I don't know how to scale up the Triceratops if one were to give it a 27 percent wider torso, but if this holds water the average Triceratops would probably have been over 9 tonnes. *Yes, I know there was an updated one done in 2017. It turned out to be severely underestimated (175 cm width when much smaller specimens were wider than that) and from what I could tell the older one was probably better
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Post by creature386 on Jan 3, 2020 19:26:00 GMT 5
Better than your previous posts. If you don't mind, I still have to nag. As was previously stated, the earlier GDI ( link)* gives a Triceratops with a 2.5 meter skull and total length of 8.26 meters a mass of about 10.5 tonnes, and I'd in fact argue it would be closer to 11 tonnes given that the parts of the head in red are excluded and that there is very little soft tissue on the legs, tail, and chest, as I did earlier. Why not 12 t? Or 11.6 t? What makes you think that the missing tissue weighs 500 kg? Did you choose 11 t because it was such a nice, round number? I don't know if you've heard that in math classes, but save rounding for the end of the calculations. HOWEVER, these mass estimates are still probably undersized at least a little bit. The width of the top view of the hyperlinked GDI is about 3/4 of the length of the skull, which would give us about ~185 cm width for the top view. Scale bars and pixels, please. For both individuals in question. |
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Post by dinosauria101 on Jan 3, 2020 19:55:06 GMT 5
Better than your previous posts. If you don't mind, I still have to nag. As was previously stated, the earlier GDI ( link)* gives a Triceratops with a 2.5 meter skull and total length of 8.26 meters a mass of about 10.5 tonnes, and I'd in fact argue it would be closer to 11 tonnes given that the parts of the head in red are excluded and that there is very little soft tissue on the legs, tail, and chest, as I did earlier. 1: Why not 12 t? Or 11.6 t? What makes you think that the missing tissue weighs 500 kg? Did you choose 11 t because it was such a nice, round number? I don't know if you've heard that in math classes, but save rounding for the end of the calculations. HOWEVER, these mass estimates are still probably undersized at least a little bit. The width of the top view of the hyperlinked GDI is about 3/4 of the length of the skull, which would give us about ~185 cm width for the top view. 2: Scale bars and pixels, please. For both individuals in question. 1: You know what, you do have a point. Closer to 11 tonnes was just a guesstimate; maybe I should say closer to 11-12 to include a wider range of mass 2: For the Triceratops in the hyperlinked GDI, I got 112.62992126 pixels for the top view, and 162.51968504 pixels for the skull. The GDI doesn't include a scalebar, but i can put together a size comp of the GDI with a scalebar. As for 'both indivoduals', what is the second individual supposed to be? |
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Post by creature386 on Jan 3, 2020 19:59:12 GMT 5
1: You know what, you do have a point. Closer to 11 tonnes was just a guesstimate; maybe I should say closer to 11-12 to include a wider range of mass You still don't use rounded or guessed numbers if you need the numbers for further calculation. Kelsey |
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