Instructor Poll

1		Many variations of underground food-storage organs have evolved in plants: bulbs, corms, tubers, tuberous roots, and taproots. What environmental factors would favor the development of underground storage organs? How would you investigate your hypothesis?
2		The sweet potato is said to have a disjunct distribution, found in two widely separated regions of the world. Species with disjunct populations have been of great interest to phytogeographers, scientists who study and attempt to explain the distribution patterns of plants. For example, plant species with disjunct distributions in both Africa and South America have been used as evidence to support the theory that these continents were once part of a single land mass that later moved apart as a result of continental drift. If you were to find a plant species with widely separated populations, what hypotheses could you come up with to account for the distribution? How would you investigate your hypotheses?
3		All varieties of cassava contain cyanogenic glycosides, yet native peoples learned to process cassava to remove the toxins. Speculate on how early cultures could have learned these techniques.