Re: Deinocheirus - size stats?

["Ray Stanford" <dinotracker@earthlink.net>]

    Rob Gay said, "When I was in Utah this summer, there were some tracks at
the College of Eastern Utah Prehistoric Museum labeled as _Deinonychus_.
They were longer than one's hand, and had two well defined toes, and one
skinny, but still obviously present, toe. Obviously, [w]e've had the debate
over trackway assignment before; but, how reliable is this assignment (not
to the genus level, obviously). Is it safe to call these dromeosaurid-made
trackways?"

    In considering even the remote possibility that you were really looking
at tracks made by an animal like Deinonychus, with a 'terrible claw', or a
dromeosaurid, one might ask: (1) Were these tracks Early Cretaceous, or of
what age?; (2) If you were looking at a sequence of footprints (trackway)
was the "skinny, but still obviously present toe" a digit II or digit IV?
(In other words, was it located on the inside of the foot or on the outer
side?); (3) If it was a digit II, and phalangeal pads were visible in the
prints, how many such pads were visible within that digit?; (4) Was there
any evidence of a claw mark immediately at the end of that digit (as in the
other two digits?), and; (5) If not, was there such a mark remarkably more
distant from the final pad impression than was the case in the other two
digits?

    That is a very minimum of observations needed to even get a vague idea
of whether or not the tracks have any remote possibility of having made by
Deinonychus or a similar animal.

    Even with the 'right' answers to these questions, one might well be
highly cautious in making too strong an affinity assignment.  If the tracks
were underprints or overprints, or otherwise of poor definition, I would say
'all bets are off'.

    I might have missed something, but I have not heard of any such tracks
at the College of Eastern Utah Prehistoric Museum being published as those
of Deinonychus. If anyone has seen such a paper, please give me the
reference. If I had to bet, though, I would put my money on the idea that
some curator or assistant took too much liberty with such an assertion.

    Does anyone have any photo(s) of the referenced tracks that could be
shared with me, privately, as a jpeg?

    It seems that reasonably diagnostic dromeosaurid footprints would
necessarily be very highly distinctive.  Finally, I suspect that
dromeosaurid feet might most clearly create prints of such character if made
in a rather soft but not too sticky substrate, such as dinosaurs were often
tracking upon in parts of Early Cretaceous Maryland.  :-}

    Ray Stanford

"You know my method.  It is founded upon the observance of trifles." --
Sherlock Holmes in The Boscombe Valley Mystery