When using a cladistic approach to systematics, which of the following is considered most important for classification?
A) shared primitive characters
B) analogous primitive characters
C) shared derived characters
D) the number of homoplasies
E) overall phenotypic similarity

Question

Quizplus · Accepted Answer

Shared derived characters, also known as synapomorphies, are considered the most important for classification in a cladistic approach. These are traits that are shared by a group of organisms and their common ancestor but not found in more distantly related organisms. This allows for the creation of monophyletic groups, which have a common ancestor and all its descendants. Shared primitive characters (A) are traits found in both the organism being studied and its ancestors, but not in more closely related groups. Analogous primitive characters (B) are traits that are similar due to convergent evolution, but do not indicate a close evolutionary relationship. The number of homoplasies (D) is a consideration, but shared derived characters are still more important for classification. Overall phenotypic similarity (E) can be useful, but it does not necessarily indicate evolutionary relatedness.

When Using a Cladistic Approach to Systematics, Which of the Following