If there were no bees it would severely adversely impact our food supply. What other things do we depend on to preserve our way of life? If things start dying off/disappearing inexplicably when do we get to a danger point of no return? What if there were no more birds? How would that affect us? What if all insects and bugs disappeared? What would happen next? Are we already living on the edge? How much wiggle room do we have before it's just too late?