Re: Triassic dino tracks in this week's Science

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

"Emma C. Rainforth" wrote:

> Sure. But because we're dealing with ichnotaxa, a "small Eubrontes"
> (e.g. Grallator) does not equate with "a small Eubrontes trackmaker".
> It simply means "a small animal whose feet are similiar to that of
> the Eubrontes trackmaker". At current resolution, this translates to
> "small theropod" vs. "big theropod". So just because Grallator is
> present, does not mean Eubrontes is or would be expected to be...

All true. However, if the prints are considered size variants, that
means they are similar in form in some way (allometry aside). What are
the chances of pseudosuchian prints just happening to be preserved in a
way that not only makes them look theropodian, but also just happen to
resemble Eubrontes, which just happen to resemble Grallator, which just
happen to be preserved in the very same deposits? 

Besides, there are three Eubrontes prints, with a stride length of
around 2 metres. All three would have to be similarly ill-preserved. I
don't know anything about pseudosuchians, but would any of them have a
pes stride length of 2m?

-- 
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Dann Pigdon                   Australian Dinosaurs:
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
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