Parables help us make sense of a mysterious world. Slow and steady, the tortoise teaches the hare a lesson in overconfidence. David has a surprise for towering Goliath.

Rather than merely adhering to national climate-change rules, industries, such as cement, can lead the way with their own global agreements
by Elaine Coles

Ethanol is taking a tumble. Once hyped as a magic brew for reducing both oil addiction and global warming, alcohol made from corn kernels is now being accused both of triggering a global food crisis and doing more ecological harm than good.

The global food crisis has brought on riots in about a dozen countries and left many panicked world leaders scrambling for answers. Alarming increases in once-affordable basic food staples such as rice, corn, and wheat have made millions more of the world's poor vulnerable to hunger and malnutrition. Past food market emergencies have been mainly regional in scope.

For most of the past century, diesel engines have been associated with smoky, smelly trucks and buses. Now there's a surprise: A new generation of diesel-powered passenger cars is delivering punchy performance and emission levels so low they pass muster in all 50 U.S. states. Boasting good fuel efficiency, the new "clean diesels" may well overtake hybrids in the market for eco-cars.

Energy is in the spotlight. Consumers and businesses are grappling with tight oil and gas supplies, while oil companies and a host of new players struggle to come up with sustainable energy sources that cut CO2 emissions. It's a bafflingly complex challenge that is unlikely to be solved anytime soon.

Set aside, for now, the really complex and costly financial implications of climate change. Ignore the tricky abstractions of carbon trading. Forget the worries over flooded cities and the ins and outs of renewable energy.

Out of more than 1,000 products examined, only one met federal standards.

Some farmers in China are taking advantage of confusing rules to falsely label food

Climate