Re: Big Dinosaur Prints Found

[Mike Taylor <mike@tecc.co.uk>]

> Date: Tue, 20 Mar 2001 11:30:12 -0500
> From: "Ray Stanford" <dinotracker@earthlink.net>
> 
> Anyhow, one trackway of rather large three-toed theropodan tracks
> (possible of the ichnogenus Kayentapus, which some writers have said
> may have been produced by Dilophosaurus) had a clearly defined tail
> drag all along the trackway, between the good-sized, beautifully
> preserved footprints.  This was definitely the trackway of a
> dinosaur and not that of some other reptile.  Furthermore, there was
> nothing ambiguous about the tail drag trace.  It was not a crack in
> the substrate, and as the trackway veered, it did likewise.

Wow.  This pretty much blows away everything I thought I understood
about dinosaurs (again :-) I can imagine how a lazy sauropod could
leave a tail-drag -- the older sauropod mounts looks believable in the
posture they give the dragging tails.  But a theropod?  When I think
of the shape of a _Dilophosaurus_, the only way I can see it making
any kind of drag mark is if the body is held in a best 1959s-style
upright posture.  Is that what was going on here?  Or are theropod
tails more dorso-ventrally flexible than I'd thought?  And if so,
didn't it entail a lot of (wasted) muscular effort to keep them off
the ground for the 99% of the time that they seem to have been held
there?

 _/|_    _______________________________________________________________
/o ) \/  Mike Taylor -- <mirk@mail.org> -- http://www.miketaylor.org.uk/
)_v__/\  "I think the idea behind PhyloCode is to get all the bickering
         done now so the future generations don't have to worry about
         it" -- T. Michael Keesey.