The Global Warming Survival Guide

The growing market for biofuel has had some unintended consequences for the world's nutritional staples. Tens of thousands of people marched on Mexico City in January to protest the skyrocketing cost of tortillas, a development linked to increased demand for corn for ethanol. A similar ripple effect is moving through Europe. German brewers warn that European Union subsidies, which support the planting of rapeseed for conversion into biodiesel, discourage farmers from planting barley, which could mean higher beer prices.

One solution: make biofuel from nonfood crops. DaimlerChrysler, for example, is promoting jatropha, a thorny plant that grows on marginal land in Latin America, Africa and India. With intensive labor, it yields high-quality biodiesel without boosting food prices. In fact, it has no value as food; it's poisonous.

This is an extended version of the article that originally appeared in TIME Magazine.