Whenever the Aspen Ideas Festival posts full videos or transcripts of its panel events, be sure not to miss the session on global food supply that took place this morning. As measured by the ever-popular "how much more did I know at the end of the session, compared with what I knew at the start" metric, for me this was the most informative 75 minutes I've spent here so far.

The panelists were: Hugh Grant, CEO of Monsanto -- whose company was, of course, a central villain of the Food Inc movie screened here earlier this week; Henrietta Fore, former administrator of USAID; Jason Clay, of the World Wildlife Fund, with experience in market-based and supply-chain efforts at conservation; and David Tilman, a biology/ecology expert from the University of Minnesota.

The benefit of the panel was the combination of alarming facts and specific solution-possibilities. Sample alarming fact: if the world population eventually tops out at 9.5 billion, 50% more than now, total food production will probably have to grow by 200%, as people eat higher up the food chain and demand more and more meat. The challenge, as several panelists put it, was to produce three times as much food on no more than the current amount of agricultural land. (About why it won't just work to cut down all remaining forests to grow food, see here.)

Sample specific solution-possibilities, or at least interesting facts: Average yields in U.S. farms are roughly three times as high as the overall average for Mexico, India, and Brazil. If those countries got to even two-thirds of the US level, it would make a huge difference in closing the "grain gap." Also: a huge share of the world's food output is wasted -- in the developing world because it rots and spoils before it can get to market, and in the US to a significant degree because of restaurant waste. Thus easy opportunities for gain. Surprising facts about animal efficiency: if it takes 2.5 pounds of grain to produce a pound of chicken, and 5 pounds to produce a pound of pork, and up to 10 pounds to produce a pound of grain-fed beef, it can take less than a pound of grain feed to produce a pound of tilapia fish. "It's all about buoyancy," one of the panelists said.  I may be hazy on a few of the details here, but the general points are right.

There was a whole lot more -- I was taking notes the whole time, while I was supposed to be moderating. Also, Hugh Grant on Monsanto manfully answered questions about the Food. Inc. movie at the start of the session. Really, an exceptional discussion: check it out when available.

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