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Re: Dromomeron and Lagerpeton query

2009/7/19 David Peters <davidrpeters@charter.net>:
>> To find out if Nesbitt et al. screwed up by assuming the pterosaurs are
>> part of their ingroup, you need to conduct a bigger analysis, say with the
>> crown of Diapsida as the ingroup and the araeoscelidians as the outgroup,
>> for example.
> This is assuming the traditional "crown group Diapsida" is monophyletic,
> which has never been tested.

That's because its monophyletic by definition.  "Crown group Diapsida"
means the most recent common ancestor of all extant diapsids together
with all its descendants.  It's not something you can test, any more
than you can test that acute angles are less than 90 degrees.