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Re: cladobabble--here we go again

Chuck Prime wrote:
>The statement would have been fine if it had said: "[The animals which
>we refer to as] the clade Maniraptora [existed], no matter what [process
>we use to classify them]."

>I suppose you also could have meant your paraphrase to say: "The clade
>Maniraptora [is a classification which I or others will continue using],
>no matter what [animals it might refer to]."

        Actually, this does not seem to get at the point. The following is a
brief summary of several articles by De Quiroz and Padian, who give an
effective philosophical discussion of these topics:
        There exists a real biological and historical grouping of animals
which may be uniquely defined as the group containing all animals sharing a
more recent common ancestral population (or "ancestor") with modern birds
than they share with _Ornithomimus_. We may be uncertain of the composition
of this group. However, it must exist, given the assumptions that there
exists at least one animal (the type) identified as _Ornithomimus_, and at
least one modern bird (say we'll use the type of Passer domesticus). We also
proceed from the assumption that all life stems from the same source, and is
linked by ancestry and descent (we will not debate this here, that is for a
different listserv).
        If I were The Watcher, The Beyonder, or the Maximortal, I could wade
through the currents of time and scoop up Maniraptora with my hands. To use
a thermodynamics metaphore, it is a phase in the system of life, a
mechanically seperable unit. Thus, in naming Maniraptora, we are not
classifying organisms into groups, but recognizing groups which exist in
nature, and seeking to determine their composition.

    Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
        "Chimp here does the killing." - Doug Mackenzie