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Re: Running, bipedal? Re: Baby dinosaur tracks from Morrison



"radially" (pear-shaped pressure lines) is only true over time, not
for an impact.

There's a very nice Milan and someone paper on that, it was cited on
the list within the last two days, IIRC.

:)
H

On Wed, Nov 3, 2010 at 4:35 PM, Saint Abyssal <saint_abyssal@yahoo.com> wrote:
> Aren't underprints physically impossible? There was a 2001 paper in the 
> Mesozoic Vertebrate Life collection which argued that the force of the 
> trackmakers weight is exerted radially through the sediment instead of 
> straight down, so although there's some compression under the track, the 
> force fades so rapidly that the idea of a traditional "underprint" or "ghost 
> print" isn't feasible.
>
> ~ Abyssal
>
> --- On Wed, 11/3/10, Thomas R. Holtz, Jr. <tholtz@umd.edu> wrote:
>
>> From: Thomas R. Holtz, Jr. <tholtz@umd.edu>
>> Subject: RE: Running, bipedal? Re: Baby dinosaur tracks from Morrison
>> To: rtravsky@uwyo.edu, dinosaur@usc.edu
>> Date: Wednesday, November 3, 2010, 3:13 PM
>> > From: owner-DINOSAUR@usc.edu
>> [mailto:owner-DINOSAUR@usc.edu]
>>
>> > On Behalf Of Richard W. Travsky
>> >
>> > On Mon, 1 Nov 2010, bh480@scn.org
>> wrote:
>> >
>> > > From: Ben Creisler
>> > > bh480@scn.org
>> > >
>> > > In case this news story has not been mentioned
>> yet:
>> > >
>> > > http://www.genengnews.com/industry-updates/morrison-
>> > > natural-history-museum-discovers-baby-sauropod-
>> > > tracks/98965127/
>> > >
>> > > Mentions tracks from baby apatosaurs with
>> possible evidence
>> > that baby
>> > > sauropods sometimes ran on hindlimbs only.
>> >
>> > Link not found. However, a similar (might even be the
>> same)
>> > article is here:
>> >
>> > http://www.geosociety.org/news/pr/10-63.htm
>> > Morrison Natural History Museum Discovers Baby
>> Sauropod
>> > Tracks Tracks of a Running Bipedal Baby Brontosaur?
>> >
>>
>> One VERY important issue (for which we will have to Wait
>> For The Paper): are the pedal prints tracks, or are they
>> undertracks? It
>> might well be that the little dino is running
>> quadrupedally, but we are sampling layers under the actual
>> muddy surface, which only
>> the pedal impression reached.
>>
>> As has been shown by Manning (among many others), knowing
>> if you are dealing with real tracks or undertracks can make
>> a LOT of
>> difference in interpretation.
>>
>> Thomas R. Holtz, Jr.
>> Email: tholtz@umd.edu
>> Phone: 301-405-4084
>> Office: Centreville 1216
>>
>> Senior Lecturer, Vertebrate Paleontology
>> Dept. of Geology, University of Maryland
>> http://www.geol.umd.edu/~tholtz/
>> Fax: 301-314-9661
>>
>> Faculty Director, Science & Global Change Program,
>> College Park Scholars
>> http://www.geol.umd.edu/sgc
>> Fax: 301-314-9843
>>
>> Mailing Address:    Thomas R. Holtz, Jr.
>>
>> Department of Geology
>>
>> Building 237, Room 1117
>>
>> University of Maryland
>>
>> College Park, MD 20742 USA
>>
>>
>
>
>
>