Reuters

Planet Earth is a giant food machine. It's done an impressive job cranking out sustenance for the masses, often aided by human ingenuity. Innovations like factory farming or pesticides have helped it keep up with the planet's booming population, even as it leapt from 2.5 billion in 1950 to 7 billion today.

But by 2050, the population will jump to 9 billion (pdf). The question is, can the machine continue to keep up?

The answer is: not really. Already, demand for food is straining the planet's ability to produce it, as the Earth Policy Institute highlights. Meat production has increased more than 600% since 1950, and demand certain types of meat are already taxing the limits of the Earth's ability to produce them:

Consider the case of beef. Farmers around the world have overstocked grasslands to keep up with demand, as EPI points out. But there's simply not enough grass to feed as many cattle as hamburger fans demand. The supply squeeze is reflected in North American beef prices, which have spiked due to droughts that dried out grassland. As a result, US herd sizes are the smallest they've been in 60 years (paywall).