It takes fifteen pounds of wild fish to get you one pound of farm tuna. Not very sustainable. It doesn't taste very good either.

For the past 50 years, we've been fishing the seas like we clear-cut forests. It's hard to overstate the destruction. Ninety percent of large fish, the ones we love - the tunas, the halibuts, the salmons, swordfish - they've collapsed.

I said, 'Don, what's sustainable about feeding chicken to fish?'

In food, issues that surround purchasing and that whole realm have a very political component and they branch into stories that can be really compelling. Just being on the farm, interacting with all these people in the industry, leads to personal narratives that can be used to make a larger point.

If you look at the carrying capacity of agricultural areas throughout the world, their ecological habitats are changing. So I think we're looking at - in our lifetime - great collapses of food services.

The history of food has never had a better biographer. Required reading for anyone who eats.

It takes fifteen pounds of wild fish to get you one pound of farm tuna. Not very sustainable. It doesn't taste very good either.