Re: Apomorphy-based definitions

["Jaime A. Headden" <qilongia@yahoo.com>]

Hoping that Mike allowed this discussion to be posted to the list ...

David Marjanovic (david.marjanovic@gmx.at) wrote to Mike Taylor 
(mike@tecc.co.uk):

<Suppose you'd be [naïve] enough do define birds as possessing feathers. 8-) 
Then the definition
would read "the first species that possessed feathers synapomorphic with those 
of *Passer*, and
all its descendants" and be abbreviated as (Feathers in *Passer*).>

  This definition would be a very bad idea. For one thing, the feathers of 
*Passer* are suddenly
the defining feature for feathers as a phylogenetic tool; ratite feathers are 
different, foir the
bulk of their morphology, and it is conceivable that Ratitae would be excluded 
from this
definition.


=====
Jaime A. Headden

  Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
  Where the Wind Comes Sweeping Down the Pampas!!!!

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