Questions to answer: 1. What has to be true at each step of evolution of the eye, from a more primitive structure to a more advanced one? 2. What advantage does a tuna get from being sort of warm blooded? 3. Can you think of a cost associated with being warm blooded? 4. What phenomenon in economics is a parallel to the evolution of eyes or the development of the tuna's heat- control system? 5. How does the traditional lnnuit diet differ from most other diets? 6. What environmental conditions drive that difference