The maximum clade credibility (MCC) tree from DengueTrees
A phylo object
http://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-7-214
Drummond, A. J., and Rambaut, A. (2007) BEAST: Bayesian evolutionary analysis by sampling trees. BMC Evolutionary Biology, 7(1), 214.
Lanciotti, R. S., Gubler, D. J., and Trent, D. W. (1997) Molecular evolution and phylogeny of dengue-4 viruses. Journal of General Virology, 78(9), 2279-2286.