How to generate all possible evol. trees

Mark Siddall mes at zoo.toronto.edu
Wed Jun 22 12:51:40 EST 1994


As was posted, PAUP will do this, BUT it becomes enormously long to do 
this for more than 11 taxa, the reason is the following:

NUMBER OF TAXA       NUMBER OF POSSIBLE CLADOGRAMS
     3                          1
     6                        105
     9                    135,135
    10                 2 x 10^6
    15                 8 x 10^12

you get the idea.

For large numbers of taxa, PAUP can generate random trees and examine the 
number of steps a matrix requires for explanation on that tree.  It uses
an all trees equiprobable model.

In addition, my software, Random Cladistics, (avail. free by ftp to 
zoo.toronto.edu as compressed util RANDOM.EXE in directory pub) will
do the same but uses a Markovian tree-growth model for random trees.
You must have your own copy of Hennig86 for my software to be of use.

Good luck.

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



More information about the Mol-evol mailing list