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Post by Infinity Blade on Apr 4, 2014 3:07:57 GMT 5
3 times its own size? They're both ~250 kilograms aren't they?
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Post by Vodmeister on Apr 4, 2014 3:56:20 GMT 5
3 times its own size? They're both ~250 kilograms aren't they? I think that pckts is talking about the really big grizzly bears from Alaska which can reach 1,400 lbs. |
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Post by Infinity Blade on Apr 4, 2014 5:09:33 GMT 5
3 times its own size? They're both ~250 kilograms aren't they? I think that pckts is talking about the really big grizzly bears from Alaska which can reach 1,400 lbs. Should that be the case, that is unfair as there are no freak individuals of Quetzalcoatlus known to pit against such a large grizzly bear. |
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Post by Deleted on Apr 4, 2014 7:09:14 GMT 5
I would take a "Van" sized grizzly any day of the week. And I'm not sure what makes you guys think bears are not aggressive, they certainly are and will fight quite readily. Even if this creature could grab a hold of the grizzly what could it do after that, it would definitely not be strong enough to hold a bear which weighs 3 times its own size. First, there was never a grizzly bear the size of a van. Secondly, we never said that grizzlies weren't aggressive, Quetzalcoatlus' dimensions is just enormous. Do you think a bear would even think of attacking a foe which visually looks to be larger than an elephant? Bears have fear too. And last but not the least, the bear is NOT 3x the size of Quetzalcoatlus. Grizzlies don't reach ~600-750 kilograms(~3x mass) and would almost never* reach anywhere near ~3x Quetzalcoatlus' volume. *Yeah, but don't start counting on spontaneous entropy decreases or such generating you a supergiant grizzly bear unless you want to wait out a time period far greater than the age of the universe to have a good chance of it. But if you want the bear to stomp this match so badly, go ahead and start the long wait.
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Post by Vodmeister on Apr 4, 2014 10:12:25 GMT 5
I would take a "Van" sized grizzly any day of the week. And I'm not sure what makes you guys think bears are not aggressive, they certainly are and will fight quite readily. Even if this creature could grab a hold of the grizzly what could it do after that, it would definitely not be strong enough to hold a bear which weighs 3 times its own size. First, there was never a grizzly bear the size of a van.
Strictly speaking, Van is a grizzly bear. Though generally, people tend to refer to mountain grizzlies as the true "grizzly bear" and coastal grizzlies as "brown bears". Mountain grizzlies max out at 850 lb, coastal brownies can get up to 1,400 lb. |
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Post by creature386 on Apr 4, 2014 18:14:44 GMT 5
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Post by Infinity Blade on Apr 5, 2014 0:00:19 GMT 5
"The size and flight mechanics of giant pterosaurs have received considerable research interest for the last century but are confused by conflicting interpretations of pterosaur biology and flight capabilities. Avian biomechanical parameters have often been applied to pterosaurs in such research but, due to considerable differences in avian and pterosaur anatomy, have lead to systematic errors interpreting pterosaur flight mechanics. Such assumptions have lead to assertions that giant pterosaurs were extremely lightweight to facilitate flight or, if more realistic masses are assumed, were flightless. Reappraisal of the proportions, scaling and morphology of giant pterosaur fossils suggests that bird and pterosaur wing structure, gross anatomy and launch kinematics are too different to be considered mechanically interchangeable. Conclusions assuming such interchangeability—including those indicating that giant pterosaurs were flightless—are found to be based on inaccurate and poorly supported assumptions of structural scaling and launch kinematics. Pterosaur bone strength and flap-gliding performance demonstrate that giant pterosaur anatomy was capable of generating sufficient lift and thrust for powered flight as well as resisting flight loading stresses. The retention of flight characteristics across giant pterosaur skeletons and their considerable robustness compared to similarly-massed terrestrial animals suggest that giant pterosaurs were not flightless. Moreover, the term ‘giant pterosaur’ includes at least two radically different forms with very distinct palaeoecological signatures and, accordingly, all but the most basic sweeping conclusions about giant pterosaur flight should be treated with caution. Reappraisal of giant pterosaur material also reveals that the size of the largest pterosaurs, previously suggested to have wingspans up to 13 m and masses up to 544 kg, have been overestimated. Scaling of fragmentary giant pterosaur remains have been misled by distorted fossils or used inappropriate scaling techniques, indicating that 10–11 m wingspans and masses of 200–250 kg are the most reliable upper estimates of known pterosaur size."Source
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Post by creature386 on Apr 5, 2014 0:59:24 GMT 5
Thanks for posting that!
I guess this is better than an over 30 year old paper.
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Post by Deleted on Apr 5, 2014 8:03:26 GMT 5
Those seem like really bad estimates given that a ~10-meter-wingspan Quetzalcoatlus has been estimated at ~500 liters(Witton, 2008), isometrically scaling that up to the theoretical ~15.5-meter-wingspan specimen of theirs would result in ~1861.938 liters. It's like saying that Moschops capensis had the same mass as a small teenage girl. |
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Post by pckts on Apr 7, 2014 23:06:06 GMT 5
Even a Kodiak Bear is considered a "alaskan Grizzly bear". The thread's title simply says "grizzly bear"
And even a mountain grizzly will still have a substantial size advantage.
That is why I was thrown off with this animal vs animal scenario
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Post by theropod on Apr 11, 2014 15:15:50 GMT 5
To be fair, the paper I posted cited this:http://www.plosone.org/article/fetchObject.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0002271&representation=PDF The cited paper: Langston W Jr. (1981) Pterosaurs. Scientific American 244: 92–102. Those seem like really bad estimates given that a ~10-meter-wingspan Quetzalcoatlus has been estimated at ~500 liters(Witton, 2008), isometrically scaling that up to the theoretical ~15.5-meter-wingspan specimen of theirs would result in ~1861.938 liters. It's like saying that Moschops capensis had the same mass as a small teenage girl. The scaling wouldn’t be isometrically in reality tough, those larger wingspan estimates simply based on animals with proportionally longer wings if I recall correctly. Turns out Azhdarchids had fairly short wings for their height and body mass… And of course, their density would be comparatively low, but there’s absolutely no way a Quetzalcoatlus could be as light as in some early figures. The 250kg figure is imo the best we have for a large, volant azhdarchid, although hypothetical flightless ones with denser bodies could be far heavier. |
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Post by Runic on Apr 12, 2014 2:01:58 GMT 5
Did pterosaur even stab stuff bigger and a small animal with their beak?
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Post by Runic on Apr 12, 2014 2:06:21 GMT 5
Just saw the pelican eating the pigeon alive.... wtf son
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Post by Infinity Blade on Apr 12, 2014 2:15:46 GMT 5
I don't see why not. I wouldn't be surprised if it pecked to defend itself, and with its full force behind that huge skull and beak, it should probably cause some severe damage.
And btw, do storks jab with their beaks? The beaks of azhdarchids kind of look like those of storks.
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Post by Infinity Blade on Apr 27, 2014 18:14:49 GMT 5
"Of course, there were likely some occasions when azhdarchids were caught out by predators: would this spell instant doom for the pterosaur? Not necessarily. Again, this is hard to say with confidence, but we note that large modern storks - which resemble azhdarchids more than any other modern species - can be far more dangerous than most folks realise. These birds can inflict severe, sometimes fatal injuries with their beaks when panicked and cornered. Children are seriously wounded or even killed by marabou storks when trying to harvest soft white contour feathers from these usually calm birds (Mackay 1950). Zoo staff routinely arm themselves against attack from captive jabiru storks because attacks are so frequent and vicious (Shannon 1987). Indeed, even relatively large animals like tapirs are no match for angry jabirus. These storks are not armed with razor-sharp, hooked beaks: they deliver this damage with their simple, long, pointed bills. Whether this means azhdarchids used their jaws as similarly formidable weapons is anyone's guess, but it demonstrates that azhdarchid-like bills can be used as fearsome predator deterrents if wielded properly. Remember, of course, that some azhdarchids probably had beaks over 2 m long, which 6-8 times longer than those of even the largest modern storks. An giant azhdarchid in a bad mood may be well worth avoiding." Source |
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