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Re: mammal definition (was "Fossil Discovery Threatens")



>I don't know that it's necessarily a dumb idea to recognize the living
>mammals as a group (these are the ones we have on hand to study, after all;
>perhaps Neomammalia would be a better term)--it just doesn't jube with the
>definition of Mammalia that most workers accept.


     "Archosauria" has the same problem; Archosauria in the traditional
sense really means "Archosauriformes" in the phylogenetic definition set by
Gauthier, with the phylogenetic defintion of "Archosauria" now referring to
a much more restricted group, a problem caused, as with Mammalia by defining
it as a crown clade based on extant groups.  My problem with this is that
establishing a phylogenetic definition is supposed reduce confusion and
create consistancy by making sure everybody is using the same term to
describe the same thing.  The trouble is, both "Archosauria" and "Mammalia"
already have established meanings in the literature and the minds of
plaeonologists.  The question becomes "Is the confusion caused by using the
definition that most workers accept instead of the defined phylogenetic one
really any worse then the confusion caused by defining a group
phylogenetically so that it differs so radically from an already established
meaning?"  "It just doesn't jube with the definition of Mammalia that most
workers accept" seems to be defeating the purpose of establishing a
phylogenetic definition, to reduce confusion.

LN Jeff

Remember, a closed mouth gathers no foot
-Steve Post

(probably a good quote for this reply)
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Jeffrey W. Martz
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