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3<HEAD>
4<TITLE>dnapenny</TITLE>
5<META NAME="description" CONTENT="dnapenny">
6<META NAME="keywords" CONTENT="dnapenny">
7<META NAME="resource-type" CONTENT="document">
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12<DIV ALIGN=RIGHT>
13version 3.6
14</DIV>
15<P>
16<DIV ALIGN=CENTER>
17<H1>DNAPENNY - Branch and bound to find<BR>
18all most parsimonious trees<BR>
19for nucleic acid sequence parsimony criteria</H1>
20</DIV>
21<P>
22&#169; Copyright 1986-2002 by The University of
23Washington.  Written by Joseph Felsenstein.  Permission is granted to copy
24this document provided that no fee is charged for it and that this copyright
25notice is not removed.
26<P>
27DNAPENNY is a program that will find all of the most parsimonious trees
28implied by your data when the nucleic acid sequence parsimony criterion is
29employed.  It does so not by examining all possible trees,
30but by using the more sophisticated "branch and bound" algorithm, a
31standard computer science search strategy first applied to
32phylogenetic inference by Hendy and Penny (1982).  (J. S. Farris
33[personal communication, 1975] had also suggested that this strategy,
34which is well-known in computer science, might
35be applied to phylogenies, but he did not publish this suggestion).
36<P>
37There is, however, a price to be paid for the certainty that one has
38found all members of the set of most parsimonious trees.  The problem of
39finding these has been shown (Graham and Foulds, 1982; Day, 1983) to be
40NP-complete, which is equivalent to saying that there is no
41fast algorithm that is guaranteed to solve the problem in all cases
42(for a discussion of NP-completeness, see the Scientific American
43article by Lewis and Papadimitriou, 1978).  The result is that this program,
44despite its algorithmic sophistication, is VERY SLOW.
45<P>
46The program should be slower than the other tree-building programs
47in the package, but useable up to about ten species.  Above this it will
48bog down rapidly, but exactly when depends on the data and on how much
49computer time you have (it may be more effective in the hands of someone
50who can let a microcomputer grind all night than for someone who
51has the "benefit" of paying for time on the campus mainframe computer).  IT
52IS VERY IMPORTANT FOR YOU TO GET A FEEL FOR HOW LONG THE PROGRAM
53WILL TAKE ON YOUR DATA.  This can be done by running it on subsets
54of the species, increasing the number of species in the run until you
55either are able to treat the full data set or know that the program
56will take unacceptably long on it.  (Making a plot of the logarithm of
57run time against species number may help to project run times).
58<P>
59<H2>The Algorithm</H2>
60<P>
61The search strategy used by DNAPENNY starts by making a tree consisting of the
62first two species (the first three if the tree is to be unrooted).  Then
63it tries to add the next species in all possible places (there are three
64of these).  For each of the resulting trees it evaluates the number of
65base substitutions.  It adds the next species to each of these, again in all
66possible spaces.  If this process would continue it would simply
67generate all possible trees, of which there are a very large number even
68when the number of species is moderate (34,459,425 with 10 species).  Actually
69it does not do this, because the trees are generated in a
70particular order and some of them are never generated.
71<P>
72This is because the order in which trees are generated is not quite as implied
73above, but is a "depth-first search".  This means that first one adds the third
74species in the first possible place, then the fourth species in its first
75possible place, then the fifth and so on until the first possible tree has
76been produced.  For each tree the number of steps is evaluated.  Then one
77"backtracks" by trying the alternative placements of the last species.  When
78these are exhausted one tries the next placement of the next-to-last
79species.  The order of placement in a depth-first search is like this for a
80four-species case (parentheses enclose monophyletic groups):
81<P>
82&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Make tree of first two species:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A,B)<BR>
83&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add C in first place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,B),C)<BR>
84&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in first place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,D),B),C)<BR>
85&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in second place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,(B,D)),C)<BR>
86&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in third place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,B),D),C)<BR>
87&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fourth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,B),(C,D))<BR>
88&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fifth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,B),C),D)<BR>
89&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add C in second place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,C),B)<BR>
90&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in first place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,D),C),B)<BR>
91&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in second place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,(C,D)),B)<BR>
92&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in third place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,C),D),B)<BR>
93&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fourth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,C),(B,D))<BR>
94&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fifth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(((A,C),B),D)<BR>
95&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add C in third place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A,(B,C))<BR>
96&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in first place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,D),(B,C))<BR>
97&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in second place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A,((B,D),C))<BR>
98&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in third place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A,(B,(C,D)))<BR>
99&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fourth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A,((B,C),D))<BR>
100&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Add D in fifth place:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;((A,(B,C)),D)<BR>
101<P>
102Among these fifteen trees you will find all of the four-species
103rooted trees, each exactly once (the parentheses each enclose
104a monophyletic group).  As displayed above, the backtracking
105depth-first search algorithm is just another way of producing all
106possible trees one at a time.  The branch and bound algorithm
107consists of this with one change.  As each tree is constructed,
108including the partial trees such as (A,(B,C)), its number of steps
109is evaluated.  In addition a prediction is made as to how many
110steps will be added, at a minimum, as further species are added.
111<P>
112This is done by counting how many sites which are invariant in the data up the
113most recent species added will ultimately show variation when further species
114are added.  Thus if 20 sites vary among species A, B, and C and their root,
115and if tree ((A,C),B) requires 24 steps, then if there are 8 more sites which
116will be seen to vary when species D is added, we can immediately say that no
117matter how we add D, the resulting tree can have no less than 24 + 8 = 32
118steps.  The point of all this is that if a previously-found tree such as
119((A,B),(C,D)) required only 30 steps, then we know that there is no point in
120even trying to add D to ((A,C),B).  We have computed the bound that enables us
121to cut off a whole line of inquiry (in this case five trees) and avoid going
122down that particular branch any farther.
123<P>
124The branch-and-bound algorithm thus allows us to find all most parsimonious
125trees without generating all possible trees.  How much of a saving this
126is depends strongly on the data.  For very clean (nearly "Hennigian")
127data, it saves much time, but on very messy data it will still take
128a very long time. 
129<P>
130The algorithm in the program differs from the one outlined here
131in some essential details: it investigates possibilities in the
132order of their apparent promise.  This applies to the order of addition
133of species, and to the places where they are added to the tree.  After
134the first two-species tree is constructed, the program tries adding
135each of the remaining species in turn, each in the best possible place it
136can find.  Whichever of those species adds (at a minimum) the most
137additional steps is taken to be the one to be added next to the tree.  When
138it is added, it is added in turn to places which cause the fewest
139additional steps to be added.  This sounds a bit complex, but it is done
140with the intention of eliminating regions of the search of all possible
141trees as soon as possible, and lowering the bound on tree length as quickly
142as possible.  This process of evaluating which species to add in which
143order goes on the first time the search makes a tree; thereafter it uses that
144order.
145<P>
146The program keeps a list of all the most parsimonious
147trees found so far.  Whenever it finds one that has fewer losses than
148these, it clears out the list and
149restarts it with that tree.  In the process the bound tightens and
150fewer possibilities need be investigated.  At the end the list contains
151all the shortest trees.  These are then printed out.  It should be
152mentioned that the program CLIQUE for finding all largest cliques
153also works by branch-and-bound.  Both problems are NP-complete but for
154some reason CLIQUE runs far faster.  Although their worst-case behavior
155is bad for both programs, those worst cases occur far more frequently
156in parsimony problems than in compatibility problems.
157<P>
158<H2>Controlling Run Times</H2>
159<P>
160Among the quantities available to be set from the menu of
161DNAPENNY, two (howoften and howmany) are of particular
162importance.  As DNAPENNY goes along it will keep count of how many
163trees it has examined.  Suppose that howoften is 100 and howmany is 1000,
164the default settings.  Every time 100 trees have been examined, DNAPENNY
165will print out a line saying how many multiples of 100 trees have now been
166examined, how many steps the most parsimonious tree found so far has,
167how many trees of with that number of steps have been found, and a very
168rough estimate of what fraction of all trees have been looked at so far.
169<P>
170When the number of these multiples printed out reaches the number howmany
171(say 1000), the whole algorithm aborts and prints out that it has not
172found all most parsimonious trees, but prints out what is has got so far
173anyway.  These trees need not be any of the most parsimonious trees: they are
174simply the most parsimonious ones found so far.  By setting the product
175(howoften times howmany) large you can make
176the algorithm less likely to abort, but then you risk getting bogged
177down in a gigantic computation.  You should adjust these constants so that
178the program cannot go beyond examining the number of trees you are reasonably
179willing to pay for (or wait for).  In their initial setting the program will
180abort after looking at 100,000 trees.  Obviously you may want to adjust
181howoften in order to get more or fewer lines of intermediate notice of how
182many trees have been looked at so far.  Of course, in small cases you may
183never even reach the first multiple of howoften, and nothing will be printed
184out except some headings and then the final trees.
185<P>
186The indication of the approximate percentage of trees searched so far will
187be helpful in judging how much farther you would have to go to get the full
188search.  Actually, since that fraction is the fraction of the set of all
189possible trees searched or ruled out so far, and since the search becomes
190progressively more efficient, the approximate fraction printed out will
191usually be an underestimate of how far along the program is, sometimes a
192serious underestimate.
193<P>
194A constant
195at the beginning of the program that affects the result is
196"maxtrees",
197which controls the
198maximum number of trees that can be stored.  Thus if maxtrees is 25,
199and 32 most parsimonious trees are found, only the first 25 of these are
200stored and printed out.  If maxtrees is increased, the program does not
201run any slower but requires a little
202more intermediate storage space.  I recommend
203that maxtrees be kept as large as you can, provided you are willing to
204look at an output with that many trees on it!  Initially, maxtrees is set
205to 100 in the distribution copy.
206<P>
207<H2>Method and Options</H2>
208<P>
209The counting of the length of trees is done by an algorithm nearly
210identical to the corresponding algorithms in DNAPARS, and thus the remainder
211of this document will be nearly identical to the DNAPARS document.
212<P>
213This program carries out unrooted parsimony (analogous to Wagner
214trees) (Eck and Dayhoff, 1966; Kluge and Farris, 1969) on DNA
215sequences.  The method of Fitch (1971) is used to count the number of
216changes of base needed on a given tree.  The assumptions of this
217method are exactly analogous to those of DNAPARS:
218<OL>
219<LI>Each site evolves independently.
220<LI>Different lineages evolve independently.
221<LI>The probability of a base substitution at a given site is
222small over the lengths of time involved in
223a branch of the phylogeny.
224<LI>The expected amounts of change in different branches of the phylogeny
225do not vary by so much that two changes in a high-rate branch
226are more probable than one change in a low-rate branch.
227<LI>The expected amounts of change do not vary enough among sites that two
228changes in one site are more probable than one change in another.
229</OL>
230<P>
231Change from an occupied site to a deletion is counted as one
232change.  Reversion from a deletion to an occupied site is allowed and is also
233counted as one change.
234<P>
235That these are the assumptions of parsimony methods has been documented
236in a series of papers of mine: (1973a, 1978b, 1979, 1981b,
2371983b, 1988b).  For an
238opposing view arguing that the parsimony methods make no substantive
239assumptions such as these, see the papers by Farris (1983) and Sober (1983a,
2401983b), but also read the exchange between Felsenstein and Sober (1986). 
241<P>
242Change from an occupied site to a deletion is counted as one
243change.  Reversion from a deletion to an occupied site is allowed and is also
244counted as one change.  Note that this in effect assumes that a deletion
245N bases long is N separate events.
246<P>
247The input data is standard.  The first line of the input file contains the
248number of species and the number of sites.  If the Weights option is being
249used, there must also be a W in this first line to signal its presence.
250There are only two options requiring information to be present in the input
251file, W (Weights) and U (User tree).  All options other than W (including U) are
252invoked using the menu.
253<P>
254Next come the species data.  Each
255sequence starts on a new line, has a ten-character species name
256that must be blank-filled to be of that length, followed immediately
257by the species data in the one-letter code.  The sequences must either
258be in the "interleaved" or "sequential" formats
259described in the Molecular Sequence Programs document.  The I option
260selects between them.  The sequences can have internal
261blanks in the sequence but there must be no extra blanks at the end of the
262terminated line.  Note that a blank is not a valid symbol for a deletion.
263<P>
264The options are selected using an interactive menu.  The menu looks like this:
265<P>
266<TABLE><TR><TD BGCOLOR=white>
267<PRE>
268
269Penny algorithm for DNA, version 3.6a3
270 branch-and-bound to find all most parsimonious trees
271
272Settings for this run:
273  H        How many groups of  100 trees:  1000
274  F        How often to report, in trees:   100
275  S           Branch and bound is simple?  Yes
276  O                        Outgroup root?  No, use as outgroup species  1
277  T              Use Threshold parsimony?  No, use ordinary parsimony
278  W                       Sites weighted?  No
279  M           Analyze multiple data sets?  No
280  I          Input sequences interleaved?  Yes
281  0   Terminal type (IBM PC, ANSI, none)?  (none)
282  1    Print out the data at start of run  No
283  2  Print indications of progress of run  Yes
284  3                        Print out tree  Yes
285  4          Print out steps in each site  No
286  5  Print sequences at all nodes of tree  No
287  6       Write out trees onto tree file?  Yes
288
289Are these settings correct? (type Y or the letter for one to change)
290
291</PRE>
292</TD></TR></TABLE>
293<P>
294The user either types "Y" (followed, of course, by a carriage-return)
295if the settings shown are to be accepted, or the letter or digit corresponding
296to an option that is to be changed.
297<P>
298The options O, T, W, M, and 0 are the usual ones.  They are described in the
299main documentation file of this package.  Option I is the same as in
300other molecular sequence programs and is described in the documentation file
301for the sequence programs.
302<P>
303The T (threshold) option allows a continuum of methods
304between parsimony and compatibility.  Thresholds less than or equal to 1.0 do
305not have any meaning and should
306not be used: they will result in a tree dependent only on the input
307order of species and not at all on the data!
308<P>
309The W (Weights) option allows only weights of 0 or 1.
310<P>
311The M (Multiple data sets) option for this program does not allow multiple
312sets of weights.  We hope to change this soon.
313<P>
314The options H, F, and S are not found in the other molecular sequence programs.
315H (How many) allows the user to set the quantity howmany, which we have
316already seen controls number of times that the program
317will report on its progress.  F allows the user to set the quantity howoften,
318which sets how often it will report -- after scanning how many trees.
319<P>
320The S (Simple) option alters a step in DNAPENNY which reconsiders the
321order in which species are added to the tree.  Normally the decision as to
322what species to add to the tree next is made as the first tree is being
323constructed; that ordering of species is not altered subsequently.  The S
324option causes it to be continually reconsidered.  This will probably
325result in a substantial increase in run time, but on some data sets of
326intermediate messiness it may help.  It is included in case it might prove
327of use on some data sets.
328<P>
329Output is standard: if option 1 is toggled on, the data is printed out,
330with the convention that "." means "the same as in the first species".
331Then comes a list of equally parsimonious trees, and (if option 2 is
332toggled on) a table of the
333number of changes of state required in each character.  If option 5 is toggled
334on, a table is printed
335out after each tree, showing for each  branch whether there are known to be
336changes in the branch, and what the states are inferred to have been at the
337top end of the branch.  If the inferred state is a "?" or one of the IUB
338ambiguity symbols, there will be multiple
339equally-parsimonious assignments of states; the user must work these out for
340themselves by hand.  A "?" in the reconstructed states means that in
341addition to one or more bases, a deletion may or may not be present.  If
342option 6 is left in its default state the trees
343found will be written to a tree file, so that they are available to be used
344in other programs.
345<P>
346<HR><H3>TEST DATA SET</H3>
347<P>
348<TABLE><TR><TD BGCOLOR=white>
349<PRE>
350    8    6
351Alpha1    AAGAAG
352Alpha2    AAGAAG
353Beta1     AAGGGG
354Beta2     AAGGGG
355Gamma1    AGGAAG
356Gamma2    AGGAAG
357Delta     GGAGGA
358Epsilon   GGAAAG
359</PRE>
360</TD></TR></TABLE>
361<P>
362<HR>
363<H3>CONTENTS OF OUTPUT FILE (if all numerical options are on)</H3>
364<P>
365<TABLE><TR><TD BGCOLOR=white>
366<PRE>
367
368Penny algorithm for DNA, version 3.6a3
369 branch-and-bound to find all most parsimonious trees
370
371
372requires a total of              8.000
373
374     9 trees in all found
375
376
377
378
379  +--------------------Alpha1   
380  ! 
381  !                 +--Delta     
382  !              +--3 
383  !           +--7  +--Epsilon   
384  1           !  ! 
385  !     +-----6  +-----Gamma2   
386  !     !     ! 
387  !  +--4     +--------Gamma1   
388  !  !  ! 
389  !  !  !           +--Beta2     
390  +--2  +-----------5 
391     !              +--Beta1     
392     ! 
393     +-----------------Alpha2   
394
395  remember: this is an unrooted tree!
396
397
398steps in each site:
399         0   1   2   3   4   5   6   7   8   9
400     *-----------------------------------------
401    0|       1   1   1   2   2   1           
402
403From    To     Any Steps?    State at upper node
404                           
405          1                AAGAAG
406   1   Alpha1       no     AAGAAG
407   1      2         no     AAGAAG
408   2      4         no     AAGAAG
409   4      6         yes    AGGAAG
410   6      7         no     AGGAAG
411   7      3         yes    GGAAAG
412   3   Delta        yes    GGAGGA
413   3   Epsilon      no     GGAAAG
414   7   Gamma2       no     AGGAAG
415   6   Gamma1       no     AGGAAG
416   4      5         yes    AAGGGG
417   5   Beta2        no     AAGGGG
418   5   Beta1        no     AAGGGG
419   2   Alpha2       no     AAGAAG
420
421
422
423
424
425  +--------------------Alpha1   
426  ! 
427  !                 +--Delta     
428  !           +-----3 
429  !           !     +--Epsilon   
430  1     +-----6 
431  !     !     !     +--Gamma2   
432  !     !     +-----7 
433  !  +--4           +--Gamma1   
434  !  !  ! 
435  !  !  !           +--Beta2     
436  +--2  +-----------5 
437     !              +--Beta1     
438     ! 
439     +-----------------Alpha2   
440
441  remember: this is an unrooted tree!
442
443
444steps in each site:
445         0   1   2   3   4   5   6   7   8   9
446     *-----------------------------------------
447    0|       1   1   1   2   2   1           
448
449From    To     Any Steps?    State at upper node
450                           
451          1                AAGAAG
452   1   Alpha1       no     AAGAAG
453   1      2         no     AAGAAG
454   2      4         no     AAGAAG
455   4      6         yes    AGGAAG
456   6      3         yes    GGAAAG
457   3   Delta        yes    GGAGGA
458   3   Epsilon      no     GGAAAG
459   6      7         no     AGGAAG
460   7   Gamma2       no     AGGAAG
461   7   Gamma1       no     AGGAAG
462   4      5         yes    AAGGGG
463   5   Beta2        no     AAGGGG
464   5   Beta1        no     AAGGGG
465   2   Alpha2       no     AAGAAG
466
467
468
469
470
471  +--------------------Alpha1   
472  ! 
473  !                 +--Delta     
474  !              +--3 
475  !           +--6  +--Epsilon   
476  1           !  ! 
477  !     +-----7  +-----Gamma1   
478  !     !     ! 
479  !  +--4     +--------Gamma2   
480  !  !  ! 
481  !  !  !           +--Beta2     
482  +--2  +-----------5 
483     !              +--Beta1     
484     ! 
485     +-----------------Alpha2   
486
487  remember: this is an unrooted tree!
488
489
490steps in each site:
491         0   1   2   3   4   5   6   7   8   9
492     *-----------------------------------------
493    0|       1   1   1   2   2   1           
494
495From    To     Any Steps?    State at upper node
496                           
497          1                AAGAAG
498   1   Alpha1       no     AAGAAG
499   1      2         no     AAGAAG
500   2      4         no     AAGAAG
501   4      7         yes    AGGAAG
502   7      6         no     AGGAAG
503   6      3         yes    GGAAAG
504   3   Delta        yes    GGAGGA
505   3   Epsilon      no     GGAAAG
506   6   Gamma1       no     AGGAAG
507   7   Gamma2       no     AGGAAG
508   4      5         yes    AAGGGG
509   5   Beta2        no     AAGGGG
510   5   Beta1        no     AAGGGG
511   2   Alpha2       no     AAGAAG
512
513
514
515
516
517  +--------------------Alpha1   
518  ! 
519  !                 +--Delta     
520  !              +--3 
521  1           +--7  +--Epsilon   
522  !           !  ! 
523  !  +--------6  +-----Gamma2   
524  !  !        ! 
525  !  !        +--------Gamma1   
526  +--2 
527     !              +--Beta2     
528     !           +--5 
529     +-----------4  +--Beta1     
530                 ! 
531                 +-----Alpha2   
532
533  remember: this is an unrooted tree!
534
535
536steps in each site:
537         0   1   2   3   4   5   6   7   8   9
538     *-----------------------------------------
539    0|       1   1   1   2   2   1           
540
541From    To     Any Steps?    State at upper node
542                           
543          1                AAGAAG
544   1   Alpha1       no     AAGAAG
545   1      2         no     AAGAAG
546   2      6         yes    AGGAAG
547   6      7         no     AGGAAG
548   7      3         yes    GGAAAG
549   3   Delta        yes    GGAGGA
550   3   Epsilon      no     GGAAAG
551   7   Gamma2       no     AGGAAG
552   6   Gamma1       no     AGGAAG
553   2      4         no     AAGAAG
554   4      5         yes    AAGGGG
555   5   Beta2        no     AAGGGG
556   5   Beta1        no     AAGGGG
557   4   Alpha2       no     AAGAAG
558
559
560
561
562
563  +--------------------Alpha1   
564  ! 
565  !                 +--Delta     
566  !           +-----3 
567  1           !     +--Epsilon   
568  !  +--------6 
569  !  !        !     +--Gamma2   
570  !  !        +-----7 
571  +--2              +--Gamma1   
572     ! 
573     !              +--Beta2     
574     !           +--5 
575     +-----------4  +--Beta1     
576                 ! 
577                 +-----Alpha2   
578
579  remember: this is an unrooted tree!
580
581
582steps in each site:
583         0   1   2   3   4   5   6   7   8   9
584     *-----------------------------------------
585    0|       1   1   1   2   2   1           
586
587From    To     Any Steps?    State at upper node
588                           
589          1                AAGAAG
590   1   Alpha1       no     AAGAAG
591   1      2         no     AAGAAG
592   2      6         yes    AGGAAG
593   6      3         yes    GGAAAG
594   3   Delta        yes    GGAGGA
595   3   Epsilon      no     GGAAAG
596   6      7         no     AGGAAG
597   7   Gamma2       no     AGGAAG
598   7   Gamma1       no     AGGAAG
599   2      4         no     AAGAAG
600   4      5         yes    AAGGGG
601   5   Beta2        no     AAGGGG
602   5   Beta1        no     AAGGGG
603   4   Alpha2       no     AAGAAG
604
605
606
607
608
609  +--------------------Alpha1   
610  ! 
611  !                 +--Delta     
612  !              +--3 
613  1           +--6  +--Epsilon   
614  !           !  ! 
615  !  +--------7  +-----Gamma1   
616  !  !        ! 
617  !  !        +--------Gamma2   
618  +--2 
619     !              +--Beta2     
620     !           +--5 
621     +-----------4  +--Beta1     
622                 ! 
623                 +-----Alpha2   
624
625  remember: this is an unrooted tree!
626
627
628steps in each site:
629         0   1   2   3   4   5   6   7   8   9
630     *-----------------------------------------
631    0|       1   1   1   2   2   1           
632
633From    To     Any Steps?    State at upper node
634                           
635          1                AAGAAG
636   1   Alpha1       no     AAGAAG
637   1      2         no     AAGAAG
638   2      7         yes    AGGAAG
639   7      6         no     AGGAAG
640   6      3         yes    GGAAAG
641   3   Delta        yes    GGAGGA
642   3   Epsilon      no     GGAAAG
643   6   Gamma1       no     AGGAAG
644   7   Gamma2       no     AGGAAG
645   2      4         no     AAGAAG
646   4      5         yes    AAGGGG
647   5   Beta2        no     AAGGGG
648   5   Beta1        no     AAGGGG
649   4   Alpha2       no     AAGAAG
650
651
652
653
654
655  +--------------------Alpha1   
656  ! 
657  !                 +--Delta     
658  !              +--3 
659  !           +--7  +--Epsilon   
660  1           !  ! 
661  !        +--6  +-----Gamma2   
662  !        !  ! 
663  !  +-----2  +--------Gamma1   
664  !  !     ! 
665  +--4     +-----------Alpha2   
666     ! 
667     !              +--Beta2     
668     +--------------5 
669                    +--Beta1     
670
671  remember: this is an unrooted tree!
672
673
674steps in each site:
675         0   1   2   3   4   5   6   7   8   9
676     *-----------------------------------------
677    0|       1   1   1   2   2   1           
678
679From    To     Any Steps?    State at upper node
680                           
681          1                AAGAAG
682   1   Alpha1       no     AAGAAG
683   1      4         no     AAGAAG
684   4      2         no     AAGAAG
685   2      6         yes    AGGAAG
686   6      7         no     AGGAAG
687   7      3         yes    GGAAAG
688   3   Delta        yes    GGAGGA
689   3   Epsilon      no     GGAAAG
690   7   Gamma2       no     AGGAAG
691   6   Gamma1       no     AGGAAG
692   2   Alpha2       no     AAGAAG
693   4      5         yes    AAGGGG
694   5   Beta2        no     AAGGGG
695   5   Beta1        no     AAGGGG
696
697
698
699
700
701  +--------------------Alpha1   
702  ! 
703  !                 +--Delta     
704  !           +-----3 
705  !           !     +--Epsilon   
706  1        +--6 
707  !        !  !     +--Gamma2   
708  !  +-----2  +-----7 
709  !  !     !        +--Gamma1   
710  !  !     ! 
711  +--4     +-----------Alpha2   
712     ! 
713     !              +--Beta2     
714     +--------------5 
715                    +--Beta1     
716
717  remember: this is an unrooted tree!
718
719
720steps in each site:
721         0   1   2   3   4   5   6   7   8   9
722     *-----------------------------------------
723    0|       1   1   1   2   2   1           
724
725From    To     Any Steps?    State at upper node
726                           
727          1                AAGAAG
728   1   Alpha1       no     AAGAAG
729   1      4         no     AAGAAG
730   4      2         no     AAGAAG
731   2      6         yes    AGGAAG
732   6      3         yes    GGAAAG
733   3   Delta        yes    GGAGGA
734   3   Epsilon      no     GGAAAG
735   6      7         no     AGGAAG
736   7   Gamma2       no     AGGAAG
737   7   Gamma1       no     AGGAAG
738   2   Alpha2       no     AAGAAG
739   4      5         yes    AAGGGG
740   5   Beta2        no     AAGGGG
741   5   Beta1        no     AAGGGG
742
743
744
745
746
747  +--------------------Alpha1   
748  ! 
749  !                 +--Delta     
750  !              +--3 
751  !           +--6  +--Epsilon   
752  1           !  ! 
753  !        +--7  +-----Gamma1   
754  !        !  ! 
755  !  +-----2  +--------Gamma2   
756  !  !     ! 
757  +--4     +-----------Alpha2   
758     ! 
759     !              +--Beta2     
760     +--------------5 
761                    +--Beta1     
762
763  remember: this is an unrooted tree!
764
765
766steps in each site:
767         0   1   2   3   4   5   6   7   8   9
768     *-----------------------------------------
769    0|       1   1   1   2   2   1           
770
771From    To     Any Steps?    State at upper node
772                           
773          1                AAGAAG
774   1   Alpha1       no     AAGAAG
775   1      4         no     AAGAAG
776   4      2         no     AAGAAG
777   2      7         yes    AGGAAG
778   7      6         no     AGGAAG
779   6      3         yes    GGAAAG
780   3   Delta        yes    GGAGGA
781   3   Epsilon      no     GGAAAG
782   6   Gamma1       no     AGGAAG
783   7   Gamma2       no     AGGAAG
784   2   Alpha2       no     AAGAAG
785   4      5         yes    AAGGGG
786   5   Beta2        no     AAGGGG
787   5   Beta1        no     AAGGGG
788
789
790</PRE>
791</TD></TR></TABLE>
792</BODY>
793</HTML>
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