Scientists warn entire branches of the 'Tree of Life' are going extinct

Washington (AFP) - Humans are driving the loss of entire branches of the "Tree of Life," according to a new study published on Monday which warns of the threat of a sixth mass extinction.  "The extinction crisis is as bad as the climate change crisis. It is not recognized," said Gerardo Ceballos, professor at the National Autonomous University of Mexico, and co-author of the study published in Proceedings of the National Academy of Sciences (PNAS).  "What is at stake is the future of mankind," he told AFP.  The study is unique because instead of merely examining the loss of a species, it exami...