BIO153H5 Lecture Notes - Lecture 3: Convergent Evolution, Phenetics, Distant Relatives
Document Summary
Phylogenetic trees are a method to organize and represent phylogenies. A node is the point from which the branches split. polytomy is when there is more than one branch emerging from one node. There are many approaches to creating trees. The phenetic approach uses an index of overall similarity. The distance between different character states is calculated and the tree is constructed by a computer. The cladistic approach examines characters shared between groups. It is based on recognizing different traits as: The reason for similar characteristics has to be distinguished: Homology - similarities due to shared ancestry. Homoplasy - reasons other than shared ancestry.
