Figure 1: Two phylogenetic trees. 'X' and 'y' mark nodes. The colored outlines are taxa (plural for taxon), and the lines leading up to the taxa are the branches of the tree. Note that even though the trees are arranged in different ways, the phylogenetic information they represent is identical. Source: Baum et al (2005) Science 310:979-980. http://digitalcommons.unl.edu/bioscifacpub/105. Is the frog more closely related to a fish or to a human Identify the node that represents the most recent common ancestor of a frog and a fish, and identify
the node that represents the most recent common ancestor between a frog and a human. Does this
makes change your answer to the question above? Note: you could have had the correct answer to start
with.
Now compare the left-hand tree to the one on the right and identify the node that represents the most
recent common ancestor between a frog and a human. Can you see how re- arranging the branches while
keeping the nodes intact does not change the relationship between the taxa?