I have been reading a few papers which allude the relationship
between phylogenetic tree symmetry and long branch attraction
artifacts. My understanding (albeit rudimentary) is that long branch
attraction can lead to tree assymetry (many independent single
-species lineages diverging sequentially).
However, I have also seen the problem stated in the reverse:
the finding of an assymetric tree should lead one to suspect that
long branch attraction is the source of the assymetry.
My feeling is that the second portrayal of the problem is
erroneous since both assymetrical and symmetrical trees
must exist in the real world.
Can anyone explain the concepts I'm alluding to more
completely? Some of what I am referring to is based
on the work of Mooers et al.
Thanks in advance,
Andrew J. Roger
roger at evol5.mbl.edu