The questions are open-ended, which means you can use your creative powers and insights from evolutionary biology to propose a hypothesis. You may use any published peer-reviewed source, which must be listed at the end of the paper.
Consider either the paper by Bramble et al. (2004) or Roach et al. (2013) on unique human locomotor or throwing abilities. The papers propose selective agents or agencies for the unique knee, leg, and shoulder adaptations; can you think of ways to test these ideas, and can you think of alternative possibilities as to which agents or agencies are responsible? Choose only one of these two papers to write this essay.