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philidor11 wrote:
<<I would argue that what you are 'testing' here is how the results with a larger aggregation (sample of all relevant animals who ever lived) of data compare to the results from subsets of the data.  You'd certainly find out something about the computer program logic's response to expanding data, but the validity of the logic is untested.>>

Ken Kinman wrote:
<<Ironically it's strict parsimony that is increasingly fogging up the landscape, and when it really starts getting thick, maybe the peanut throwing and ridicule will finally end.>>

I see now a new difference in opinion here.  It's not cladistics or phylogenetic taxonomy you guys don't like, it's the assumption of parsimony in evolutionary theory.

Perhaps you're right, and parsimony isn't the way that evolution works.  I know I wasn't around for the last 4 billion years, and I really doubt anyone else on this list was, so we can't have a direct observation of evolution in large scale events.  Perhaps instead of parsimony, evolution operates by way of munificence, lavishly generous transformations.

Where does that leave the scientist though?  Do we re-program our cladistic analysis packages to find the most munificent trees, rather than the most parsimonious ones?  How many billions of trees would we come up with then?  When we find trees with topology like:

  |  `--Avialae
        |  `--Echinodermata

Do we stop and then wonder to ourselves, "well maybe parsimony is the better assumption?"

What I am getting at is small scale evolutionary changes that have been observed by living breathing humans tend to be parsimonious.  There are not examples of fruit flies becoming sea urchin analogs within 3 generations, and then becoming fruit flies again 17 generations later, or some other munificent evolutionary event.  There's really no reason to believe that this short term parsimony wouldn't be extended onto the long-term evolutionary history of life on Earth (although I know that that statement itself invokes parsimony), so I am not sure why you berate parsimony so much.

So what if parsimony doesn't come up with the tree you constructed in your head?  What are you left with in the absense or parsimony?  Munificence makes science become impossible: there are so many infinitely more complicated schemes why bother testing any of them?

Peter Buchholz

PS see the link below for a nice discussion of William of Ockham and his "razor."