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cladistics question



One question that I have had with cladistics for a long time was the
time factor.  As an example, the ceratosaurs at least used to be
considered "basal" or "primitive" theropods, right?  Yet they didn't
appear until tens of millions of years after the earlier more derived
theropods, a huge expanse of time in which a great deal of evolution
could and probably did occur.  So how can they be considered primitive
or basal.  It was suggested to me today that this might be an example of
paedomorphogenesis so the the ceratosaurs are actually more derived but
retain characters from more primitive times.  What do you all think of
this idea?

Also I have heard of someone attempting straticladistics, merging
cladistics data with stratigraphic data to get better answers.  Can
anyone give me more information on this work?

Thanks,

Joe Daniel