People believed there was an ever-lasting supply and killed them by the thousands, commercial hunters attracted them to small clearings with grain.

What about supply? The three environmental trends—the shortage of fresh water, the loss of topsoil and the rising temperatures—are making it increasingly hard to expand the world's grain supply fast enough to keep up with demand.

Unable to buy grain or grow their own, hungry people take to the streets.

To lower domestic food prices, some countries limited or stopped their grain exports.

The surge in world grain prices in 2007 and 2008—and the threat they pose to food security—has a different, more troubling quality than the increases of the past.

The result is falling water tables ( ' , 地下水位) in countries with half the world's people, including the three big grain producers—China, India and the U.S.

The more recent steep climb in grain prices partly results from the fact that more and more people want to consume meat products.

On the demand side, those trends include the ongoing addition of more than 70 million people a year, a growing number of people wanting to move up the food chain to consume -72- highly grain-intensive meat products, and the massive diversion ( ' , 转向) of U.S. grain to the production of bio-fuel.

Indeed, even before the steep climb in grain prices in 2008, the number of failing states was expanding.

Increasing water shortages prove to be the biggest obstacle to boosting the world's grain production.

In response to those restrictions, grain-importing countries are trying to nail down long-term trade agreements that would lock up future grain supplies.

In contrast, the recent surge in world grain prices is trend-driven, making it unlikely to reverse without a reversal in the trends themselves.

During the second half of the 20th century, grain prices rose dramatically several times.

As incomes rise among low-income consumers, the potential for further grain consumption is huge.

A quarter of this year's American grain harvest will be used to produce bio-fuel for cars.

A fourth of this year's U.S. grain harvest will go to fuel cars.

a decrease of grain production            

Nadeau notices the pre-made macaron-and-cheese boxes in Scott's shopping cart and suggests she switch to whole grain macaroni and real cheese.

On the demand side, those trends include the ongoing addition of more than 70 million people a year, a growing number of people wanting to move up the food chain to consume highly grain-intensive meat products, and the massive diversion of U.S. grain to t

The three environmental trends—the shortage of fresh water, the loss of topsoil and the rising temperatures—are making it increasingly hard to expand the world's grain supply fast enough to keep up with demand.

Most Americans don’t eat enough fruits, vegetables or whole grains.

In most cases, the human waste is used on grain crops, which are eventually cooked, minimizing the risk of transmitting water-borne diseases.

Another factor is the squeeze that conventional dairy farmers have felt as the price of grain they feed their cows has gone up, tightening their profit margins.

By replacing expensive grain feed with regenerative management practices, grass-fed farmers are insulated from jumps in the price of feed.

The rest is feed-lot confined and fed grain and corn.