Interpreting a Phylogenetic Tree (Part 3)

Some trees have a single branch point from which all branches originate. This is called the root of the tree. The node closest to the root of the tree represents the most recent common ancestor for all organisms in the tree.

Same phylogenetic tree as the previous slide, an arrow points to the root of the tree, just below the orangutan branch.
A rooted phylogenetic tree of primates.