RE: Of Tyrant Kings and "running" elephants...

[GUY LEAHY <xrciseguy@q.com>]

Mark,
 
In the T. rex book John Happ describes a Triceratops skull which has 
healed-over bite marks on the left supraorbital horn and left squamosal, 
indicating that (a) the Triceratops was attacked by a T. rex, and (b) the 
Triceratops survived the attack.  Happ also cites a reference by Tanke and 
Currie (1998) where they describe *unhealed* bite marks on hadrosaur cranial 
elements, suggesting that tyrannosaurs may have attacked hadrosaurs by applying 
a crushing bite to the head-neck region.  Cool stuff!
 
Cheers,
 
Guy

________________________________
> From: marksabercat@q.com
> To: xrciseguy@q.com; kent@cs.uoregon.edu
> CC: dinosaur@usc.edu
> Subject: RE: Of Tyrant Kings and "running" elephants...
> Date: Wed, 14 Jan 2009 05:56:46 +0000
>
>
>
>
>
>
>
>
> If you consider the possibility that tyrannosaurids were ambush predators as 
> has been proposed, perhaps it would make sense to do a study comparison of 
> the known and projected tyranno limb proportions [including assumed juveniles 
> (Jane) and mature adults (Sue, Stan)] with that of their potential prey that 
> would be likely to have an equivalent speed potential, or slower, for each 
> projected onotogenetic stage. Hadrosaurs would be a good initial category for 
> this, since at least one individual at the Tyrell definitely was a 
> (surviving) prey. If Jane is a Tyrannosaurus, its proportionately large 
> forelimbs compared to those of mature adults might imply a more significant 
> function in capturing prey than in older individuals.
>
> Mark
>
> MARK HALLETT PALEOART
> 170 W. Ellendale Ave./ Suite 103, #414
> Dallas, OR 97338 USA
> e-address: marksabercat@q.com
> website: www.hallettpaleoart.com
> phone: (503) 831-1164/ fax: (503) 831-1544
>
>
>
>
>> From: xrciseguy@q.com
>> To: marksabercat@q.com; kent@cs.uoregon.edu
>> Subject: Of Tyrant Kings and "running" elephants...
>> Date: Sun, 11 Jan 2009 19:44:21 -0700
>>
>>
>> Mark and Kent,
>>
>> I just received the following book from Amazon Friday:
>>
>> http://www.amazon.com/Tyrannosaurus-Tyrant-King-Life-Past/dp/0253350875/ref=sr_1_1?ie=UTF8&s=books&qid=1231726945&sr=1-1
>>
>> I haven't sat down to read it in detail yet, but it looks pretty cool! In 
>> particular I noticed a contribution by a certain Dr. Stevens... :-)
>>
>> Now if only the "Jane" Burpee symposium would ever see the light of day... 
>> ;-)
>>
>> Speaking of "Jane" I know the majority opinion is that "Jane" is a juvenile 
>> T-rex, but there is one osteological feature I'm wondering about. All adult 
>> tyrannosaurs have a large bladelike pubic boot. This feature is also present 
>> in juveniles of Albertosaurus, Daspletosaurus and Tarbosaurus. In "Jane", 
>> the anterior expansion appears to be absent... ???
>>
>> I was watching the amazing footage from "Planet Earth" last night of the 
>> elephant-lion encounter.
>> During parts of it the elephant's gait appears to come *very* close to a 
>> trot, though whether it was or not would probably require analysis.
>>
>> Concerning running tyrannosaurs, I don't think there's much doubt that 
>> juveniles/subadults could run... the question is whether adults 
>> (particularly T.rex) could do it. Part of the argument that big tyrannosaurs 
>> could run is that most modern vertebrates do not display significant 
>> ontogenetic shifts in gait with increasing size. There is one example of 
>> this, though, which may or may not be relevant.
>> Juvenile Australian salt-water crocodiles sometimes exhibit a galloping 
>> gait, which they primarily use to quickly escape to the water from land. 
>> This gait has been documented in crocs
>> up to 1.5 m long, but larger animals have never been seen using this gait. 
>> Perhaps the larger ones are so big that it is biomechanically impossible???
>>
>> Cheers,
>>
>> Guy
>>