But as the rest of your comment makes clear, you think humans are evil
And lo! A straw man did descend from upon high and claimed himself lord! The good people, knowing his form, did set fire to him and burned his fallacy unto the ground.
we mess up the one thing that matters, Mother Nature
Well now, y'see that's where I'm a bit of an agnostic on the whole thing. Is it AGW? Or is it just GW? Are we making it worse? Or better? Will it be as dreadful as for told, or just a bit uncomfortable? Either way, I'm happier to take steps that might just keep things in a zone that suits us best. Oh whoops - does that make me evil?
This worries you more than infant mortality rates or poverty - things that make human life crappy.
But behold! Upon seeing the ashes of the straw man on the ground; the great beast False Dichotomy did raise his head and roar! Only for the good people the rip out the beast's tongue and stab it to death.
You know what could cause a massive rise in infant mortality? Crop failure. Drought. Guess what AGW is being fingered for...oh my yes; that and more.
And by "[living] with natural rhythms more" I meant more eating locally (i.e. seasonally), wasting less, and generally reducing our footprint from all that (plus a bit more).
I put it to you that struggle of resources will cause more infant mortality and increase poverty more than trying to solve the potential problem. Why are you so afraid of option 2)? Is it because you would have sacrifice? Not some nameless poor bastard in Botswana? Is it because you (and if you are posting here, you are probably one of the richest people on the planet, with one the highest standards of living and life expectancy; i.e. you are a Westerner or in the developed East) might have to pay a teensy-weensy, ickle-wickle little more for that cafa-mocha-latte?
But it's me who some kind of human-hater simply because I don't want to shit where I sleep and mess up my only home.