Resumen de Back from the brink
Humans have already transformed most of the biosphere beyond anything their early ancestors could have imagined, clearing, ploughing, burning, building, damming, domesticating, driving to extinction, dousing with chemicals and even changing the climate. Surely at some point, the biosphere will simply collapse in the face of such a massive and unrelenting onslaught. Some ecologists and global change scientists say that they are heading rapidly for a global tipping point--a threshold beyond which the entire biosphere will shift into a new and mostly undesired state. Others are convinced that no theoretical or empirical evidence exists for such a claim, and that a widespread belief in the existence of such a point of no return threatens to push ecological science and its application in the wrong direction. Here, Ellis examines the evidence.
