Re: Tapejara Military Drone

[Mark Witton <Mark.Witton@port.ac.uk>]

One thing about the 'inspiration' for this project, though: they seem to have a 
slightly iffy idea about Tapejara anatomy. As far as I'm aware, there isn't yet 
any evidence for an extensive soft-tissue cranial crest in Tapejara like that 
of Tupandactylus and 'T.' navigans: every Tapajara skull I've seen lacks the 
fibrous bone lining the base of large pterosaur soft-tissue crests, and either 
Sinopterus or Huaxiapterus (I can't quite remember which at the moment, and my 
literature is safely stored in the university where it can't trouble me in the 
evening - freedom from the PhD at last!) demonstrates that some tapejarids only 
had very low soft-tissue crests. It does seem that some people can't get past 
those crests as flight-essential implements and will glue a huge crest on any 
pterosaur without one, regardless of the evidence. Anyone remember the 
conclusions of Czerkas and Ji that headcrests were _essential_ flight 
components for all pterosaurs? Well, someone had better break that
 news to the dozens of crestless pterosaurs out there. I'd rather not myself: 
I've seen how annoyed folk can get when their flights are canceled for no good 
reason.  

Anyway, good luck to Chatterjee and his chums and all that. I'll be very 
interested to see the finished product: a mechanical flying and walking 
pterosaur sounds like a great idea. And if it doesn't work, they can sell the 
designs to B-movie makers and we can all enjoy _The Termodactyl_: part animal, 
part machine - all prehistoric terror!

Right, there must be something more sensible to do around here somewhere. Ah, 
there's something.

Mark

--

Mark Witton

Palaeobiology Research Group
School of Earth and Environmental Sciences
University of Portsmouth
Burnaby Building
Burnaby Road
Portsmouth
PO1 3QL

Tel: (44)2392 842418
E-mail: Mark.Witton@port.ac.uk
>>> Mike Habib <habib@jhmi.edu> 07/10/08 7:02 PM >>>
I'm very happy to see them doing this project, as well.  However, I am  
slightly concerned with the apparent fixation/focus on using the head  
and crest to generate the rolling and yawing moments.  It can be used  
to do so, but a) the wings should still be the primary control surface  
(especially for roll) and b) Ross Elgin et al have data suggesting  
that large turning moments about the head would be damaging to the  
upper cervicals and basicranium in most taxa (dsungeripterids, with  
their massively expanded post-occipital process might have bucked the  
trend in this regard).

Still, it's neat stuff :)

--Mike



On Oct 7, 2008, at 1:18 AM, jrc wrote:

> Doesn't matter that it has been done before, and doesn't matter  
> thant pterosaurs aren't dinosaurs -- I'm glad to see Sankar doing  
> it !!
> I don't know if the group of previous builders they're joining is  
> select, but it sure is small :-)
> JimC
> P.S.  If they are doing a true membrane wing, they are in for quite  
> a steep learning curve.  If a semi-rigid wing like MacCready, it  
> will be a lot easier.

Michael Habib, M.S.
PhD. Candidate
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205
(443) 280-0181
habib@jhmi.edu