ambiguous characters.

[Atilano Contreras-Ramos]

        Dear systematists:  After running PAUP and obtaining a tree(s),
when looking at the list of character changes there are single and double
lined arrows.  An arrow with a double line is an unambiguous change and
it is found under both ACCTRAN and DELTRAN reconstructions. Most of the
time a change with a single lined arrow is different (e.g. from 0 to 1
or from 2 to 1, or absent) at the same node in an ACCTRAN vs a DELTRAN
tree.  I have characters in which the same change occurs at the same node in
both optimizations, and yet such change is indicated by a single lined
arrow.  I would appreciate some insight into the meaning of this notation
and the term ambiguous character change, as utilized to interpret output
from a phylogenetic analysis.  Thanks in advance!

PS:  I hope this is not some sort of artifact of my analysis.

....................................................................
Atilano Contreras-Ramos         |
Univ Minnesota, Dept Entomology |       Save the              ::
St. Paul, MN 55108; USA.        |       biosphere!            /
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