Logic of cladistics

Mark Siddall mes at zoo.toronto.edu
Mon Jun 13 10:52:57 EST 1994


In article <mezwick-120694194150 at pbmac-16.ucdavis.edu> mezwick at ucdavis.edu (Mike Zwick) writes:
>
>But I think the central question may be:  Is it possible to get other
>information about the processes that resulted in the characters you are
>observing?  To push the analogy some more, if you have independent bird
>watchers tell you that these birds always (or perhaps very often?) fly
>through Norfolk, Va, then should you incorporate this information into your
>reconstruction of the path?  In this case then, you would know (or be
>pretty certain) that the parsimony solution would be wrong.  I think some
>cladists (with more extreme views than yours) would suggest that there is
>on way to ever know about the processes involved, and thus you should
>always rely on parsimony.  

I do, in fact, have relatively extreme views.  Though I will (and have)
concede that the implication of proceses is that the straight line
is not neccessarily "true", I have yet to see such a consensus of
"bird-watchers", except perhaps in the one area of weight of transversion
over transition... but even there, there is some debate as to what the
weight should be, even if all agree that there should be weight.

Mark

-- 
Mark E. Siddall                "I don't mind a parasite...
mes at vims.edu                    I object to a cut-rate one" 
Virginia Inst. Marine Sci.                     - Rick
Gloucester Point, VA, 23062



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