1. Phylogenetic Trees

2. An old and controversial question: What is our relationship to the modern species of apes? Consider the following species: gorilla, chimpanzee, orangatang, and gibbon Which is our closest evolutionary kin? On the other hand are these species more closely related to each other than they are to us? An examination of sequences for the HindIII Restriction Enzyme in these and 7 other primates revealed agreement of between 67% and 93% of the positions in the 898bp long sequences. Human Chimpanzee Gorilla Orangutan Gibbon Human Chimpanzee Gorilla Gibbon Orangutan

3. We can ask and answer some interesting questions based on the construction of the phylogenetic tree. If the following tree is correct, what can we say about our relationship with the apes? Human Chimpanzee Gorilla Orangutan Gibbon If we accept the other tree from the pair and use the fact that gorillas and chimpanzees are African in origin, while Orangutans and Gibbons are Asian, what can we deduce as the most likely place for the first appearance of Humans? Human Chimpanzee Gorilla Gibbon Orangutan

4. Unfortunately, knowing the Phylogenetic Distances, does not infer the shape of the tree. For example consider the following unrooted tree below A B C D E Unfortunately, we can not on this evidence alone construct a unique rooted version of the tree. For example, both of the following could be deduced. E A B D C A B D C E These trees are topologically as well as biologically different. However, both are possible without further evidence on which to base the construction.