Re: maniraptor taxonomy, etc.

["Ken Kinman" <kinman@hotmail.com>]

Jeffrey,
    As I have said on earlier occasions, exactly where you make the cuts on 
a continuous tree of life are unavoidably arbitrary to some extent.  The 
exact point where the three ossicles are "fully" developed, we can certainly 
quibble about, but in my opinion, it is far, far less arbitrary and less 
destabilizing than anchoring "mammals" on monotremes (whose primitive 
ancestry is virtually unknown and speculative).
    Based on the three ossicles, multituberculates have long been 
classified as mammals.  But whether multituberculates belong to a crown 
clade Mammalia (anchored on monotremes) is far less certain.
    So to answer your question, mammalogists tended to agree more on what 
constituted a mammal before the cladists started trying to reform it into a 
cladistic "crown group".
                        ------Ken Kinman
P.S.  Got to call it quits for today.  My brain is tired, and even my 
fingers are slowing down.  Definitely bedtime.
*******************************************************
> From: "Jeffrey Martz" <jeffmartz@earthlink.net>
> Reply-To: jeffmartz@earthlink.net
> To: <kinman@hotmail.com>, <dinosaur@usc.edu>
> Subject: Re: maniraptor taxonomy, etc.
> Date: Wed, 19 Jul 2000 21:56:41 -0000
>
>
>
> >Yes.  A good idea, but it only solves one small problem.  Call me
> >old-fashioned, but I just prefer "characterizing" taxa rather than
> >"defining" them.  Both approaches have drawbacks, but I think the >former
> is best for the long term.  Mammalia based on the three >auditory ossicles
> is far more useful than one anchored on fossil-poor >monotremes (in the
> past, present, and the forseeable future).
>
>
>     Why?  What happens if when we find a primitive "mammal" or group of
> mammals that seems to have three sort of but not quite ear ossicles?  Are
> they "kind of" mammals?  How fully adapted do the bones have to be for
> hearing before it becomes a mammal?  What happens when you get a fossil 
> form
> where the condition of the ear ossicles is debatable?  Did taxonomists 
> using
> morphological defintions really agree any better about the membership of
> groups before phylogenetic taxonomists came along?
>
> LN Jeff
>
> He who stops at being better stops being good.
> -Oliver Cromwell
>
> Fear not those who argue but those who dodge.
> -Marie von Ebner Eschenbach
>
> Jeffrey W. Martz
> 3002 4th St. # C26
> Lubbock, TX
> 79415
> http://www.homestead.com/illustrations/Illustration
> (806) 747-7910

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