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Re: cladistics question

At 12:51 PM 7/21/98 -0500, Joseph C. Daniel wrote:
>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.

   Any particular reason why, in general, they couldn't have first evolved
tens of millions of years before they first appear in the fossil record?

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