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Re: Protoavis?

At 05:37 PM 10/19/97 -0500, Jonathan R. Wagner wrote:
>        However, most terrestrial vertebrate workers whose methods are
>reproducable and consistant (i.e. cladistic) seem to prefer to leave
>stratigraphy out of their analyses. Why? Well, because the terrestrial
>record is so poor that it biases the data. Is this a rational approach? At
>least one group thinks not, and are testing their assertions using computer
>models. George Olshevsky will be pleased.

   Not to mention the fact that there is no guarantee that the *fossil
record* is chronologically correct.  Given the vagaries of fossilization I
can see how it would be possible for a descendant species to be fossilized
first before the suriving populations of the ancestral species throws off a
fossil (such as the ancestral being upland and the descendants lowland, as
hypothesized for ceratopians by, I think, Horner).  If one does not take
this into account and states categorically that descendant *lived* before
the ancestor because it's that way in the *fossil record*, it would be very
easy to get the phylogeny wrong.

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