The diagram below shows the branching tree diagram for humans. The text box below it shows the set of derived shared characteristics for the branching tree. A slanting, horizontal line is shown. On the extreme left, there is a label that says, Common Ancestor. Along the slanting, horizontal line there are five dots labeled from left to right as 1, 2, 3, 4, and 5. There is one vertical line between each of the consecutive five dots. The lines are labeled from left to right as Perch, Frog, Pigeon, Rats, and Human. A text box below the branching tree diagram is labeled Derived Shared Characteristics. In the box it says from left to right, Terrestrial during all stages, Jaws, Walking on two legs, Mammary glands and hair, and Four limbs.

Look at the possible derived shared characteristics, shown in the text box. Think about where these should be placed along with the branching tree diagram. From the text box, select a shared derived characteristic that humans and rats have. Explain why you think humans and rats share this characteristic?