When it comes to global environmental challenges, we often focus on the impact of fossil fuels -- as we should.

But I think we need to focus a similar amount of attention to the world's food system, and the damages it causes.

Why?

First, consider the fact that agricultural production now covers roughly 35-40% of the land surface of the planet -- by far the single biggest use of land on Earth.

This has wiped out more ecosystems and species than anything else we have done.