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SICKLE-CLAW FOOTPRINTS AND DIDACTYLY



Peter Von Sholly wrote:
<<I would not expect MANY of these foorprints, I would expect SOME.  It seems
dromaeosaurs are turning up everywhere these days.  I think the reason
there anen't any is that the animals didn't walk on two toes.  We are
looking for prints that don't exist.  Of course I could be wrong, but would
like proof- I just want the answer, not to be right.  I agree with most of
the other stuff you said.>>

Even if they did walk on three toes, their footprints would be very very
distinctive.  The regular thereopod foot design has digits 2 and 4 about the
same length, with digit 3 longest.  Dromaeosaurs and Saurornithoidids have
altered this foot design (independantly) so that digit 2 is extremely short
(and would have an even shorter impression because of the greatly arcing
claw) and digits 3 and 4 are nearly the same length.  Again, I will draw a
diagram in equal area font of what a 'normal' theropod foot looks like, and
what a sickle-claw's foot looks like

"Normal" Theropod Foot
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|||
\|/
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Sickle-Claw Foot
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|||
\|/
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[Again, copy and paste these into a .txt document if your server doesn't use
an equal area font.  The sickle-claw's foot is a right foot.]

Peter also wrote:
<<Is there an existing true didactyl animal that has three or more functional
toes?>>

There are none alive now that I know of, but a good example is the basal
dinosauromorph _Lagerpeton chanerensis_ which is, btw, hands-down just about
the weirdest animal I've ever seen.  _L_'s digit 2 is extremely short and
would not touch the ground, digit 3 is longer, and digit 4 is the longest.
 It looks very strange, check out Sereno and Arcucci 1993 for some
eye-opening diagrams of this animals foot.

Peter Buchholz
Tetanurae@aol.com

Damn woman, I just gave you sweet lovin' five minutes ago!  What are you
trying to do, kill me?