Maximum likelihood rooted tree of 6 peach MIKCC-type MADS-box genes. Tree was constructed using nucleotide sequences and an HKY evolution model. The PtMADS27 sequence was used as outgroup. The right numbers at each interior branch indicate maximum likelihood bootstrap support, and the left numbers indicate Bayesian clade credibility values of 1000 replicates. Branch lengths are proportional to the number of nucleotide changes. Black circles in the internal nodes correspond to ancestral sequences in the reconstruction experiment described in Figure 5.