There was a famous/infamous article SOMEWHERE about 10 years ago, arguing that vegetarianism causes more animals to die than carnivorism (coz we took all their food!). Sounds ludicrous to me, but this was a detailed, mathematical analysis of plant consumption levels vs. animal body weights.
As a heavy meat-eater but vegetarian wannabe, I found it a fascinating piece. Does anyone recall it, and could point me in the right direction? I want to say The New Republic, but that's almost a blind guess at this point.