DOLLOP carries out the Dollo and polymorphism
parsimony methods. The Dollo parsimony method was first
suggested in print in verbal form by Le Quesne (1974) and was first well-specified
by Farris (1977). The method is named after
Louis Dollo since he was one of the first
to assert that in evolution it is harder to gain a complex
feature than to lose it. The algorithm
explains the presence of the state 1 by allowing up to one forward
change 0-->1 and as many reversions 1-->0 as are necessary
to explain the pattern of states seen. The program attempts
to minimize the number of 1-->0 reversions necessary. Part of Phylip.
5 6 Alpha 110110 Beta 110000 Gamma 100110 Delta 001001 Epsilon 001110 |
Dollo and polymorphism parsimony algorithm, version 3.6 Dollo parsimony method 5 species, 6 characters Name Characters ---- ---------- Alpha 11011 0 Beta 11000 0 Gamma 10011 0 Delta 00100 1 Epsilon 00111 0 One most parsimonious tree found: +-----------Delta --3 ! +--------Epsilon +--4 ! +-----Gamma +--2 ! +--Beta +--1 +--Alpha requires a total of 3.000 reversions in each character: 0 1 2 3 4 5 6 7 8 9 *----------------------------------------- 0! 0 0 1 1 1 0 From To Any Steps? State at upper node ( . means same as in the node below it on tree) root 3 yes ..1.. . 3 Delta yes ..... 1 3 4 yes ...11 . 4 Epsilon no ..... . 4 2 yes 1.0.. . 2 Gamma no ..... . 2 1 yes .1... . 1 Beta yes ...00 . 1 Alpha no ..... . |