Comments to Cladistics/Eclecticism
tdib at OCEANCONSERVANCY.ORG
Tue Feb 12 12:32:52 CST 2002
From: SKÁLA Zdenek
: taxa (as you correctly pointed) are the *named* groups. Hence, either you
have as many taxa as clades ((2^n)-1; n=number of species) or you need rules
to distinguish where to split a cladogram.
...- the "real" system (including all clades as taxa) cannot be practically
handled and the useful one (only some clades are named) is only arbitrary.
What a science!
I realy don't get your point. Perhaps it is more understandable if I were to
focus on the defintion of taxa. You say "named" clade, with an emphasis on
_named_ (i.e to actually put a name on it). I would say taxa are
"recognized" clades. They are "named" in the loose sense of the word,
perhaps they do not have a formal name, but they are available to the
scientific community, they can be pointed to on a graph (cladogram), they
can be referred to with words (third node down from X). Actually labeling
them with a name is, at that point, a trivial matter. You seem to claim
repeatedly that this is somehow arbitrary. But what is the point of calling
it arbitrary, as if the _scientific result_ was somehow the result of
non-scientific criterea? That is not the case. There is nothing arbitrary
about cladistic recognition of clades. If our character analysis methodology
identifies a clade, it is recognized - even if it is only referenced by the
intersection of two lines on a graph, rather than a word. Putting a formal
name on it or not does not change the scientific nature of the result, and
so the process is not arbitrary in a scientific sense.
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