Cladograms

What is it? A way to show evolutionary history between organisms. Phylogeny: The Evolutionary History of an organism.

Key Terms Clade: Node Derived Character: A group of organisms A place where the branches split off . Represent the most recent common ancestor. Derived Character: A characteristic shared by some groups of organisms, but not by other groups.

General rules 1.) Read the cladogram from left to right. 2.) Species on the left are older species than species on the right. 3.) Any organism to the right of a derived character has that characteristic. 4.) Any organism to the left of a derived character does not have the characteristic. 5.) The first species to the right of a derived character were the first organisms (in the list provided) to develop that trait.

Example: 1.) What was the first organism listed to develop jaws? 2.) What characteristic makes salamanders different from lizards? 3.) What evolutionary development separates perch & hagfish from all of the other organisms? 4.) According to the cladogram, which species is the oldest? Youngest?