9a. In the above figure, explain what the pink lines are showing for the evolutionary tree.

9b. The figure to the right shows a whale’s tail flukes and how the tail moves to propel the whale forward as it swims. In the above figure, where does the first appearance of tail flukes during the evolution of cetaceans?

9c. Explain how the evolutionary changes in the back legs and tail helped cetaceans become better adapted for living in water.