RE: ABOUT THE REVERSED HALLUX AND...

["Williams, Tim" <TiJaWi@agron.iastate.edu>]

Emma Rainforth wrote:

> Ok, back to Steropoides: about all you can say is it's a dinosaur with 3
> anteriorly-directed digits and a highly variable hallux impression
> (variability largely due to difference in preservation between
> specimens).

Firstly, thanks for the informative reply.

Secondly, I'll remember to take Lull's interpretations of tracks with a
grain of sodium chloride.

Thirdly, what do you mean by 'highly variable hallux impression' - relative
*position* or *relative depth* compared to the front digits?  I ask because
Melchor et al. (2002) noted that tridactyl and quadrupedal footprints from
Argentina were identical except for the presence of a hallucal impression.
In other words, the hallux (being higher than the amterior digits) was
captured only when the foot sunk deep enough in the sediment.



Tim


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Timothy J. Williams, Ph.D. 

USDA-ARS Researcher 
Agronomy Hall 
Iowa State University 
Ames IA 50014 

Phone: 515 294 9233 
Fax:   515 294 9359