Fig. 5From: Generating normal networks via leaf insertion and nearest neighbor interchangeIllustration the undesired condition in Theorem 2 that prevents from applying s a child rotation. Here, the reticulate node r and its child Leaf 4 are first inserted into the tree edges entering v1 and v2(i.e. 2) in a normal network (top), generating a normal network (middle). But, child rotation to left leads to a tree-child network that is no longer normal (bottom), in which y does not satisfy the normal conditionBack to article page