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Figure 4.5: (a) A binary species tree. (b) A non-binary gene tree with genes sampled from (a). (c) Binary resolution of gene tree (b), yielding a binary tree with three duplications and three losses. (d) Gene tree (b) reconciled with species tree (a), yielding a non-binary tree with three duplications and four losses. (e) Gene tree (b) following rearrangement. The polytomy has been resolved and the weak edge has been rearranged to eliminate a duplication.

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