I've read articles and we're far beyond the sustainable level that's why everything is begining of to finally collapse. The experts vary from 1/2 billion up to 5 billion at the most. The last time we were at 5 billion was July 11th. , 1987. It is celebrated annually as World Population Day. We officially crossed the threshold of sustainability. Enjoy the ride it's all been downhill since then.Fuck you. You have no idea what "level is sustainable." We are all here, and the global population will begin to contract long before we reach your "dream" of so-called overpopulation. You just hate human life. All your bullshit about pretending human life isn't human life is just rhetoric to advance your agenda of eliminating humans from the world. What a fucking scumbag. If the word "evil" has any meaning...