I was talking with a friend the other day about animal and diet-related issues (I'm vegan, he's an omnivore) and we started talking about permaculture. He suggested to me that, since human beings have screwed up natural ecosystems in this country so badly, they have ethical responsibilities to restore whatever level of homeostasis is possible in order to maintain some sort of environmental integrity. He then told me that the way to do this was for humans to mimic ecosystems by raising animals using permaculture methods. In this way, he sees raising and killing animals such as bison and chickens morally defensible because it may be the most effective way to restore what has been destroyed. What does everyone think of this argument?