If you're like me, you enjoy eating, look forward to eating, and have assumed for pretty much your entire life that you would be able to keep eating for as long as you were alive. That is, if you live in a first-world country you have to figure that you will die of AIDS, cancer, heart disease, gunshot wound, drug overdose, nuclear terrorism, or car accident before you will die of starvation. Ha ha! Turns out you actually should worry about starving to death—at least, this British guy does. He argues that rising population, rising energy costs, climate change, and the crushing poverty that most agricultural workers worldwide live under could combine to create a “food crisis” not unlike the oil crises we've already seen. (It's a long article, but worth skimming at least.) He adds that the increased reliance on biofuels will mean that less of the crops we grow will be used for food, thus worsening the hypothetical future food shortage.
He lives in the UK, which imports way, way more food than the US does, so Americans shouldn't necessarily worry too much about this (not that Americans will worry about anything anyway), but the US now imports more food than it exports, and some of that food comes from China, which doesn't hold its food industry to the same rigorous quality-control standards that our FDA does in regards to American slaughterhouses. And while Tyler Cowen, who is smarter than me, isn't all that worried, we should remember that food is not infinite.
We might not end up actually starving, but food could get a lot more expensive if erosion, global warming, and random natural disasters/God start working together. For instance, the price of 40 ounces of beer in my neighborhood was be two bucks in 2006, and now it's three—a huge increase, percentage-wise. We should remember that most of the people who were born on this planet had to deal with food shortages, and this period of plenty is an aberration.