A case in which the optimal tree under the MDC criterion contains at least one cluster that does not occur in any of the input gene trees.

Abstract

<p>Three gene trees over the taxon-set {<i>a</i>, <i>b</i>, <i>c</i>, <i>d</i>, <i>e</i>}. The tree that minimizes the total number of extra lineages and that consists of only clusters induced by those three trees is the leftmost one. It requires seven extra lineages to reconcile all three gene trees.</p