PPT Slide
Tree of Life
Problem: how to build the tree of life
Tree terminology
Nestings and triplets
Supertree
Some desirable properties of a supertree method (Steel et al., 2000)
Aho et al.ís algorithm (OneTree)
Mincut supertrees
Collapsing the graph (Semple and Steel mincut algorithm)
Cut the graph to get supertree
My mincut supertree implementation darwin.zoology.gla.ac.uk/~rpage/supertree
A counter example: two input trees...
Mincut gives this (strange) result
Problem: Cuts depend on connectivity (in this example it is a function of tree size)
So, mincut doesnít work
What mincut doesÖ Öand does not do
Modifying mincut supertree
Uncontradicted information assume we have k input trees
Classifying edges
Modified mincut
If no tree contradicts an item of information, is that information always in the supertree?
No! Steel, Dress, & B–cker 2000
Future directions
Email: r.page@bio.gla.ac.uk
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