Human history is rife with examples of natural phenomenon radically changing his existence — the ice ages and smallpox, to name two. The AIDS virus has had a profound effect on the sexual behavior of many people the world over. Now, a mysterious protein, the prion, is about to change the eating habits of many people in the West and those aspiring to the standards of "developed" nations. The timing is perfect!
Population growth and improving standards of living are putting pressures on natural resources, including water and arable land, not only to feed a growing number of people but also to feed them in the manner of "developed" societies. The term "sustainability" arises in this context.
Some people would argue that the AIDS virus is nature's way of reining in unchecked human expansion and, likewise, that bovine spongiform encephalitis, also known as mad cow disease, is forcing beef-eating cultures to reconsider this luxury food.