https://gi.cebitec.uni-bielefeld.de/ 2026-04-22T22:32:18+0200 https://gi.cebitec.uni-bielefeld.de/ https://gi.cebitec.uni-bielefeld.de/ttps://gi.cebitec.uni-bielefeld.de/lib/tpl/aggi-theme/images/favicon.ico text/html 2022-12-22T11:45:45+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/a?rev=1671705945&do=diff 1,2,3,4,5,6,7,8,9,10,11 -> (1,(2,(3,(4,(5,6,7),8),9),10),11); text/html 2022-12-22T11:17:19+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/b?rev=1671704239&do=diff The first spoiler is supposed to convey that there is a 1-1 mapping between a list of n taxa and Christmas tree Newick notations where the trunk for an internal node is always in the middle. This might leave you with 2 questions: * How many lists are there for n taxa? text/html 2022-12-22T10:52:53+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/c?rev=1671702773&do=diff The Newick notation with the “trunk” in the middle is not unique. For example, we could write the given tree as (A(C(E,G,F)D)B); or as (B(C(E,G,F)D)A); so swapping taxa A and B. In fact, this can be done for any pair that is on the same “level” text/html 2022-12-22T11:02:42+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/d?rev=1671703362&do=diff One idea might be to just try it out for a simple example. text/html 2022-12-22T11:05:08+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/e?rev=1671703508&do=diff On Christmas Trees with 3 taxa Waterman always terminates because they are just binary trees with 3 taxa that someone rooted on the internal node. text/html 2022-12-22T11:07:37+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/f?rev=1671703657&do=diff What happens when Waterman cannot “split” the edge because it “lands” on an internal node? text/html 2022-12-22T11:09:14+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/g?rev=1671703754&do=diff What if when the previous spoiler happens that's where the node is supposed to go? text/html 2022-12-22T11:13:14+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/h?rev=1671703994&do=diff Christmas trees are trees, so their path metric is additive! text/html 2022-12-22T11:36:35+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/home?rev=1671705395&do=diff Spoilers for Christmas Sheet :) Hi, first of all, happy holidays! These spoilers introduce in very small steps how I would solve it. That doesn't mean that there is no other way to solve the corresponding exercise. Also, try to use them sparingly and one at a time, i.e. read a spoiler, think about it and then if you still have no idea proceed to the next one. text/html 2022-12-22T11:18:36+0200 Anonymous (anonymous@undisclosed.example.com) https://gi.cebitec.uni-bielefeld.de/teaching/2022winter/phylogenetik/christmasspoiler/i?rev=1671704316&do=diff If you use a reconstruction method that always reconstructs binary trees, applied to a Christmas Tree path metric, it will result in 0-edges that can be collapsed into a multifurcation.