As Cladistics and "Eclecticism", Aves, paraphyly flow on

Thomas DiBenedetto tdib at OCEANCONSERVANCY.ORG
Mon Feb 4 13:06:21 CST 2002

-----Original Message-----
From: Dave Walter
...Cladograms represent testable hypotheses and
have provided great insight into the evolutionary history of the Acari, but
I know that even the best cladogram is not the ultimate truth.
So does everyone else
So, while I
might rib some friends over their continued use of traditional but probably
paraphyletic groups (e.g. Oribatida, Endeostigmata), I use them myself
because they are well known, hold a lot of  information (even if it isn't
the best available), and maintain stability while a more mature system is
under development.
So can we assume that you are not advancing an arguement for the superiority
of the immature system?
The rocks are pretty obvious, although no one seems to want to look at
them.  For example, we all know (although some insist the contrary) that
evolutionary events are not exclusively dichotomous.
Could you tell us who has ever insisted to the contrary?
This is a simplifying assumption that is necessary for the technique to work
Sez who? I dont think it is an assumption at all, and it certainly is not
necessary for the technique to work well.
 but our favoured model of speciation (allopatry) could easily generate
simultaneous branching events.  Sympatric speciation may be locally
dichotomous, but is also open to the generation of multiple species from a
single ancestral species (as recent work on frogs demonstrates
Who is arguing with this?
 I've learned that the inherently paraphyletic nature of
speciation events is one of the things that are best not talked about, but
it must make even the most fundamentalist of cladists uneasy.
Who taught you that this is best not talked about? We were talking about it
here a couple of weeks ago. I tried to make the point that it doesn't make
me uneasy, because I dont think that it makes any sense at all to call
speciation "inherently paraphyletic". And I tried to explain why. I
recognize that perhaps my arguments made no sense to you, but I dont think I
can be accused of avoiding the issue. Do you have any specific objections to
my points?
 More importantly, it is becoming increasingly obvious that reticulate
is important in many, if not most, sexual groups.
I don't know that this is "increasingly obvious" - I sense that it has been
known all along. "Strict cladists" have been publishing their thoughts on
reticulation for decades - once agian, what are your specific objections to
their points?

Tom DiBenedetto

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