Figure 1

A species tree with each leaf labeled with its corresponding genome. For simplicity, we consider all the genes to be positively signed. The last line below each leaf is the gene set and multiplicity of each gene. Single circles indicate speciation nodes, while double-circles indicate WGD nodes. Applying the procedure described in the text leads to the gene set assignment and multiplicity given as labels of internal nodes. This assignment leads to the indicated insertion and losses.