Least common ancestor
From BioPerl
Least Common Ancestor diagram
The least common ancestor (also known as the most recent common ancestor) of a set of node is the lowest node in the tree (relative to the tips) which is the parent of all of them. In the figure, the LCA of the nodes boxed in grey is indicated by the arrow.
The Bio::Tree::TreeFunctionsI provides an implementation of this in the get_lca function.
Note that the lca of a node 'A' and its decendant 'B' is 'A', not the ancestor of 'A'.
