Re: Dinosaur footprint trackway found

[Dann Pigdon <dannj@alphalink.com.au>]

Quoting Richard Hing <Richard.Hing@port.ac.uk>:

> There's pictures here of some of the tail drags from the sauropod:
> 
> http://news.bbc.co.uk/1/hi/sci/tech/7680444.stm
> 
> I also remember hearing about other trackways that show the same thing as
> well. I thought that dinosaurs were meant to keep their tails up off the
> ground? It seems a simple point but I've never heard it mentioned. Is there
> an explanation? 

There may have been less impetus to keep the tail aloft in soft mud than over 
rougher, more 
abrasive terrain. Having the tail contact the ground in muddy conditions may 
even have helped - a 
sauropod in slippery mud may have needed as much contact with the substrate as 
possible to 
prevent them slipping over. Spreading some of the weight of their hind quarters 
on the tail may 
also have helped prevent their hind legs from sinking too far into the mud. 

If these tracks were layed down during a dry spell, then large animals would 
have had to risk 
becoming mired in the mud in order to drink. I suspect sauropods would have 
done everything 
possible to lessen that risk. Elephants will crawl up slippery river banks with 
their elbows in contact 
with the ground when they have no other route to cross a river, but that's 
certainly not their usual 
way of getting around.

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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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