New Scientist: Predictions that climate change alone could lead to the extinction of more than one-fifth of plant and animal species before the end of the century have often come under fire, and not just from climate-change deniers. Some biologists are sceptical because the predictions are largely based on theoretical models. Now, the most detailed study yet of one group of species "" lizards "" suggests extinction levels could indeed be as bad as predicted. Crucially, the new forecast is based on …