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Re: HELP DESPERATELY NEEDED



R. Oreinstein wrote...
> This kind of classification, you will notice, depends entirely on who an
> animal's ancestors were - it says nothing about what it looks like or how
> much it has changed.  And, of course, by this system birds are also fishes,
> and so are we, since we are descended from the common ancestor of (say)
> herrings and crossopterygian fishes.

    Cladistics makes the assumption that evolution is a process of
imply adding to the list of prexisting characters, without taking into
account features that are lost or very radically modified.  For example,
the fact that reptiles are a group of animals with traits inherited from
a common ancestor, but ignores the fact that some features, such as
scales and ectothermy, were lost in mammals and birds.  Yes, I know
that endothermy and hairs are modifications of these, but who can tell
me that recgnizing that they are HIGHLY modified in mammals and birds,
but shared by all reptiles, is not evolutionarily important?  Cladists
on this list frequently say that thier system is the only taxonomy that
takes evolutionary relationships into account, but in this regard
I feel that cladistics is strongly lacking.
     A truly comprehensive phylogenetically based taxonomy NEEDS
paraphyletic groups.
    Into the abyss...

LN Jeff
O-