Do you understand evolutionary trees? (Part Two)
In the first installment of this series, we encountered the common misconception that the order of the terminal nodes ("tips") on an evolutionary tree reflects the actual relatedness among the species represented. Simply rotating some internal nodes without affecting the branching order ("topology") of the tree -- and thus, making no change to the relationships among species -- showed that that the order of tips on a tree is actually arbitrary. What matters is the way that the species are connected through their common ancestors.
This time, we will deal with misconceptions about the…