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Re: Who says dromaeosaurs can't fly?



You observed:
<Part of your discussion suggests that the character "volancy" has to be one
of the ones evaluated in the analysis.  However, there is some merit to not
including a particular feature in an analysis in order to avoid circular
arguments (i.e., assuming what you are trying to prove).  You can run the
analysis without that particular attribute, then map the observed
distribution of that feature onto the most parsimonious tree(s).>

Flying, being a behavior, is obviously not something that can be seen in a
fossil.  So I think that you are implying a series of physical attributes
that are so substantively related to flying that possession of all or a
sufficient number implies that the animal is a flyer.
If so, that means you DO have a circularity, in the sense that observing the
possession of all these attributes has given you a pre-conclusion.
If, and I may be misreading you, you purposely leave out one of these
attributes in doing your cladistic analysis, then it seems that what you are
testing is simply the ability of the program to resupply what is 'missing',
as opposed to breaking up the attributes into separate components.  And that
would depend on the quality of the program, whether it includes the
connection you're looking for.
This is the problem of the 'complex' of functionally related characters that
I've never been quite clear about.