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RE: Tyrannosaurus Tail Torque‏

   Thanks for finding me the full version. It took me forever just to find that 
crappy sped up clip. The gazelle/dear at 7:44 is the same animal and it's 
limping complete with infected leg as it gets up and runs off. You can see the 
same swollen, putrid looking black spot on its leg in frame 7:50. I think a 
false trichotomy is being set up around these lizards. Do some varanids have 
have what look like venom glands yes, do wild dragons have enough bacteria in 
their mouths to kill (slowly) yes, can they kill simply by biting their prey to 
death yup. Why is it that one method is being focused on to the exclusion of 
the others? There is no reason why all three can not be used in a situational 
manner. Not saying you are doing this, just something I noticed while reading 
about them on the web. Also I think the way I worded my last post gave the 
wrong impression: I wasn't trying to suggest that these lizards are like cobras 
and vipers. The videos I've seen show them walking up to !
much larger animals and almost casually biting their lower legs. What I have 
noticed is that they will continue to attack an animal (large or not) for as 
long as they can. Obviously something the size of a bull or some other large 
ungulate is going to get away most of the time, but the wound seems to (like in 
the video) get badly infected. This is something that can happen with *any* 
bite wound in the wild, so I think too much is made of it. However, I do think 
dragon victims are probably far more likely to get a severe infection or blood 
poisoning when compared to the victims of other predators due the 57 or so 
strains of virulent bacteria in their mouth. 
Oprah narrates this...where is David Attenborough when you need him?
> Muscles can store strain energy, though it is often small compared to the 
> storage capacity of tendons (Alexander & Clark 1977). I don't know if any 
> >elastic storage tests have been performed on the caudofemoralis, though it 
> would appear to be plenty powerful enough to handle long walks, or bursts >of 
> acceleration all on its own.
  That's interesting, I didn't know that. What about the shanks? The ankle 
seems to have been the "weakest link" in their legs, so Is it possible that as 
theropods grew larger certain muscle systems shifted towards a more "spring" 
like system to store energy and compensate for their weight? If so, would there 
be any evidence of it on the bone? I guess you would have to look at the 
scarring on macropod (kangaroo) limbs and compare them to other animals, but 
even then... The reason I find this so interesting is because such a system 
seems to remain efficient as weight and/or speed increases. 
Simeon Koning

> Date: Sun, 21 Nov 2010 19:57:33 -0800
> From: pristichampsus@yahoo.com
> To: dinosaur@usc.edu
> Subject: Re: Tyrannosaurus Tail Torque‏
> --- On Sun, 11/21/10, Sim Koning wrote:
> > -----
> >
> > Regarding Komodo dragon's and their bite. Watch the video
> > and you'll notice that the dear's leg is *rotting* due to a
> > bite. They walk up to ungulates and bite them on the leg,
> > they get an infection and then they track them down and eat
> > them while they are still alive. There are plenty of other
> > videos showing them biting animals on the leg for the same
> > reason. These animals eat rotten *putrid* meat on the
> > shoreline... you WOULD NOT want to get bit by one.
> >
> > http://www.youtube.com/watch?v=KfTgkJHpdsM
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> Not to get too off on a tangent here, but this is the non-sped up version of 
> the video you linked to, with the relevant section highlighted.
> http://www.youtube.com/watch?v=ViisuDKqKuI&t=6m53s
> Documentaries are tough to judge for examples of animal behaviour as one must 
> take into account how the footage was chopped up to "tell the story." In this 
> case, it looks like the entire attack took place in one day. The actual 
> attack takes place at 7m44s, assuming it is the same deer (if slowed down 
> enough one can see the deer that was attacked had a healthy left rear leg).
> The point remains that there has never been a credible observation of Komodo 
> dragons using bite and release as a means of killing their prey (the dragon 
> in the video backs away at one point for what looks like "fear" of 
> retaliation from the deer before it collapses).
> Walter Auffenberg (1981) took extensive notes on his observations of wild 
> dragons hunting. His notes include observations on natural attacks, as well 
> as staged attacks (where his team tethered a goat to a post and waited for a 
> dragon to come by). In the case of the latter, he also took pictures and 
> drawings of the killing process. At no point in these attacks did the dragon 
> ever just walk off and wait for the animal to die. In fact it was quite the 
> contrary, with Auffenberg describing the attacks as extremely violent affairs.
> Fry et al (
> nd that it causes hypotension (as demonstrated at 8m28s in the video) which 
> seems to aid dragons in taking down large prey, but in no means is this their 
> primary mode of hunting.
> Honestly the only reptiles that have ever been shown to reliably use a "bite 
> and release" strategy are vipers.
> _____________________________________________________________
> >
> >
> > Also, more on topic. Do you guys think it's possible that
> > giant theropods could have had an elastic strain energy
> > storage tendon/s in their lower legs (like macropods) that
> > may have given them more "free" energy while running? I was
> > just reading about how such a system remains efficient even
> > when weight is increased. I also suspect that the
> > caudofemoralis was very elastic and may have stored energy
> > as the tail "wagged" side to side. What do you guys think?
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> Muscles can store strain energy, though it is often small compared to the 
> storage capacity of tendons (Alexander & Clark 1977). I don't know if any 
> >elastic storage tests have been performed on the caudofemoralis, though it 
> would appear to be plenty powerful enough to handle long walks, or bursts >of 
> acceleration all on its own.
> More on this very subject in the very near future. :)
> Jason
> References
> Auffenberg, Walter, 1981, The Behavioral Ecology of the Komodo Monitor, 
> Florida University press, pgs: 406.
> Alexander, R.MCN., Bennet-Clark, H.C. 1977. Storage of Elastic Strain Energy 
> in Muscle and Other Tissues. Nature. Vol.265:114-117
> Fry, B., Wroe, S., Teeuwissed, W., van Osch, M.J.P., Moreno, K., Ingle, J., 
> McHenry, C., Ferrara, T., Clausen, P., Scheib, H., Winter, K.L., Greisman, 
> L., Roelants, K., van der Weerd, L., Clemente, C.J., Giannakis, E., Hodgson, 
> W.C., Luz, S., Martelli, P., Krishnasamy, K., Kochva, E., Kwok, H.F., 
> Scanlon, D., Karas, J., Citron, D.M., Goldstein, E.J.C., Mcnaughtan, J.E., 
> and Norman, J. 2009. A Central role for Venom in Predation by Varanus 
> komodoensis (Komodo Dragon) and the Extinct Giant Varanus
> 06