How are cladistics and cladograms related?
A cladogram is a diagram used in cladistics to show how organisms are related to one another. Cladograms are constructed so that there are as few changes from one organism to the next as possible. An example of a cladogram is shown below.
Remember, cladistics is a method of classifying organisms that groups organisms according to derived characters.
Organisms within one group should have features that organisms in another group with different ancestors do not have. These traits or features are shared within the group and were present in the common ancestor (so the traits are derived). Another word for a shared, derived trait is synapomorphy.