Dr. Mike Walden, North Carolina Cooperative Extension economist in the College of Agriculture and Life Sciences at N.C. State University, responds:

"I think without a doubt it's the growing world middle class. I think this has been one of the most unheralded implications of our world economy. The middle class has been growing by leaps and bounds in the world. For example, 100 years ago, only 12 percent of the world population would be classified as middle class; 20 years ago, it was 33 percent. Today, it is 50 percent; 50 percent of the world now has what we would call a middle class standard of living. And this is expected to go higher. This has big, big implications for the world. Obviously one is that there is a general rising standard of living around the world. Another implication is there will be changing purchasing patterns. For example, food. Middle class families eat different kinds of foods - for example, more meat - than non-middle class families. So that will be a big implication for farmers and food. Energy use. Energy use goes up as your standard of living goes up, so that's a challenge. So lots of implications here, but I think we can't deny the fact that the world is getting better, simply in terms of a rising standard of living."