These days you can fly to far corners of the world and eat the pretty much the same food as you could back home. There's pizza in China and sushi in Ethiopia.
A new scientific study shows that something similar is true of the crops that farmers grow. Increasingly, there's a standard global diet, and the human race is depending more and more on a handful of major crops for much of its food.
At the same time, all over the world, people are eating a bigger variety of foods. But until now, no one had crunched the numbers to see whether global diets were overall getting less diverse, or more.
"We wanted to know, really, how many crops feed the world, and what's happening with them," says Colin Khoury, a visiting researcher at the International Center for Tropical Agriculture, or CIAT, in Cali, Colombia.
Khoury and his collaborators went through 50 years of data collected by the United Nations' Food and Agriculture Organization. And they uncovered two big trends.