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does the best substitution model for a phylogeny tree differ between one method to the other ?

I am using MrBayes, PhyML and phangorn to build the trees for a certain data set. I have used ProtTest and it identified LG+I+G+F to be the best substitution model for the maximum likelihood method (PhML). My question is, can I use the same substitution model in Mr Bayes (Bayesian analysis) and phangorn (nearest neighbor) , or do I need a different test for each method?

phylogeny subsititution-model

1 answer

You may use the same model for MrBayes (if possible to specify this model in MrBayes), or use MrAIC to find the best model.

Nearest-neighbour is a method to perform tree rearrangement to search the parameter space, no relation to the evolutionary model you choose.

but in MAFFT server, you can identify one of three substitution models for neighbor joining method.

[Substitution model (valid when NJ is selected): JTT
WAG Alpha
Poisson]

Not all programs implement all models. For example, I do not know if the latest MrBayes implement all models tested with ModelTest, I know an earlier version (I think 3.1 but may be wrong) implemented only a subset of the models found in ModelTest.

Anyway, if you are doing ML and bayesian phylogenetic inference, there is no need for NJ, which in general is less accurate.

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