Imagine a world in which cities are abandoned and our population has dropped by 90 percent. A world in which we have wreaked havoc on our delicate ecosystems and nature has begun to reclaim Earth. Once-bustling cities have fallen silent except for the rustle of the wind through the grass and trees that have cracked through the collapsing pavement. Humans have not walked these urban streets for years.
Does it seem like the stuff of science fiction? According to the world's top scientists, it...Full Story