Cunningham, C.W, Omland, K.E, Oakley, T.H. 1998.  Reconstructing ancestral character states: a critical reappraisal.  Trends in Ecology and Evolution
13
:361-366

 

Using parsimony to reconstruct ancestral character states on a phylogenetic tree has become a popular method for testing ecological and evolutionary hypotheses.  Despite its popularity, the assumptions and uncertainties of reconstructing the ancestral states of a single character have received less attention than the   challenging endeavor of reconstructing phylogenetic trees from many characters. Recent research suggests that parsimony reconstructions are often sensitive to violations of the almost universal assumption of equal probabilities of gains and losses. In addition, maximum likelihood has been developed as an alternative to parsimony reconstruction, and has also revealed a surprising amount of uncertainty in ancestral reconstructions.