Erle Ellis, Geography and Environmental Systems, was recently quoted in the Nature article written by Virginia Gewin, Science and politics: Hello, Governor. “Although there is little disagreement that abrupt shifts occur in Earth systems, including climate and the composition of ecosystems, some scientists baulk at the suggestion that there is enough evidence to predict a single tipping point for the whole planet. “I thought it was a great review of the evidence for rapid shifts in ecology, but then it switched to a series of unsupported statements — at best a hypothesis — about how a global tipping point in the …