Cladogram Analysis Worksheet

Cladogram Analysis Worksheet

Carefully analyze the cladograms provided in each section and answer the questions that follow. Use your understanding of evolutionary relationships, common ancestors, and derived characteristics to interpret the diagrams.

Cladogram Interpretation

Below is a cladogram illustrating the evolutionary relationships among several organisms. Study it carefully to answer the following questions.

1. Which organisms share the most recent common ancestor?

2. Identify a derived characteristic that is shared by organisms C and D, but not by organism A.

3. Which organism is the outgroup in this cladogram?

Multiple Choice Questions

4. In a cladogram, what does a node represent?

5. Which term describes a group of organisms that includes a common ancestor and all of its descendants?

Fill-in-the-Blanks

6. A   is a diagram showing the evolutionary relationships among various biological species.

7. Shared derived characteristics are also known as  .

8. The principle of   suggests that the simplest explanation for evolutionary relationships is usually the best.

Short Answer Questions

9. Explain the difference between a homologous structure and an analogous structure, and how this relates to cladogram construction.

10. Describe how molecular data (e.g., DNA sequences) can be used to construct or refine a cladogram.

True or False

11. All organisms on a cladogram evolved from a single common ancestor.

12. The length of the branches on a cladogram always indicates the amount of evolutionary time.