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biplanes, teeth and metatarsals



        On the subject of the Sopwith and Fokker triplane, the reason why
the Sopwith can turn so well is that it has an enormous amount of wing. It
uses these surfaces to pull itself into tiht turns with the lift. The
Fokker is probably more maneuverable because it has three wings, which
means even more wing area. 
        By the time WWII came around, somebody had realized that
meanueverability really wasn't the only key factor in fighter planes- many
or most of the kills had resulted from one plane making a quick, straight
run at the other, none of this twisting and turning stuff. So spitfires,
Messerschmidts and F-15s are all built with the concept of speed in
mind.

[ Before we drift back to the subject, I should note that when I
  originally wrote the lines that Steve recently resurrected (which
  lead to the above), another prominent list member contested (via
  private e-mail) my contention that the Fokker Dr-1 was more
  maneuverable than the F-16.  To the best of my knowledge, my
  statement was correct, but that determination probably depends on
  how exactly you define "maneuverability".  If anyone wants
  additional discussion of the subject, I'd appreciate it if you went
  off list (by writing directly to me or Nick or whoever else might
  see appropriate).  Thanks and sorry for the interjection; I felt
  honor bound to bring up the objection.  -- MR ]

        On the subject of teeth and overbites (and to be more on-topic) I
dn't think that the overbite had to have prevented the presence of lips.
I went through a brief period where I thought nutritive foramen might tell
us something about the presence of beaks vs. teeth, but came away sadly
disappointed. (for those of you who don't know, these are the little
blood-carrying holes along dino jaws I refer to). 
        What I DID notice is that In big-toothed T. rex, the foramen on
the lower jaware much lower down, roughly following the big maxillaries.
They are very close to the lip at the incisors, however. So just maybe
this indicates where lips attached. And T. rex lips attached lower down on
the dentary would allow the big teeth to slide in between gum and lip,
sheathing them. Allosaurus' foramen are higher up, at the lip of the
dentary. 
Finally, in Feduccia's book (which I agree is very good except for that
bit about birds not evolving from dinosaurs) there is a tarsometatarsus
IDed as enantithorne. It is quite short, with a very small digit 4,
regular digit 3, and enormous digit 2 with a joint that would apparently
have allowed the toe to hyperextend! It didn't say how big it was. Name
was "Yungavolucris brevipedalis". (I mean, metatarsal 2,3,4, actually, the
tarsometatarsus is apparently all that's known).
        Yet more trouble separating birds and dinos, I wonder?

        Nick L.