MrAIC.pl is a Perl script for calculating AIC, AICc, BIC, and Akaike weights (for a review, see Burnham and Anderson, 2002) for nucleotide substitution models. Likelihood scores under different models are estimated using PHYML
pMrAIC is the version of MrAIC runs parallel instances of PHYML
MrModeltest is a modified version of David Posada’s Modeltest. “Modified version” means that it was rewritten to compare 24 instead of 56 models of nucleotide substitution (basically a Modeltest version 1.0). On the other hand, all of the 24 models can be implemented in MrBayes version 3. Furthermore, MrModeltest uses (by default) four different hierarchies for the likelihood ratio tests.