I misread that at first too, but animal agriculture. i.e. stuff grown for fodder. It's more efficient to fuel a human on food grown in the ground than on an ani

I misread that at first too, but animal agriculture. i.e. stuff grown for fodder. It's more efficient to fuel a human on food grown in the ground than on an animal fed on food grown in the ground. (I'm not vegan or otherwise promoting absolutes, it's just easier to explain/understand in the extreme I think.)