Difference between revisions of "Phylogenetics: Compositional Heterogeneity Lab"
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== Simulated data and the true tree == | == Simulated data and the true tree == | ||
− | [[ | + | [[File:Nt-comp-het-tree.pdf|thumb|right]] The tree on the right was used to simulate data using the program p4. |
== Ordinary models yield the compositional attraction tree == | == Ordinary models yield the compositional attraction tree == |
Revision as of 19:34, 30 March 2014
EEB 5349: Phylogenetics | |
The goal of this lab is to introduce you to the influence of compositional heterogeneity on phylogeny. Compositional heterogeneity means that the equilibrium nucleotide frequencies (or amino acid frequencies for protein data) change across the tree, something that is not accounted for by the standard nucleotide and amino acid models, which assume stationarity (transition probabilities do not change across the tree and one set of equilibrium frequencies applies to every point along any edge of the tree). Non-stationarity can lead to compositional attraction artifacts in which tips with similar nucleotide composition group together even though they may be completely unrelated. |
Contents
Under Constructions (should be finished later today, March 30, 2014)
Simulated data and the true tree
The tree on the right was used to simulate data using the program p4.Ordinary models yield the compositional attraction tree
Non-homogeneous models yield the true tree
- Question answer