destruction by thirds

Global warming presents the gravest threat to life on Earth in all of human history.

The planet is warming to a degree beyond what many species can handle, altering or eliminating habitat, reducing food sources, causing drought and other species-harming severe weather events, and even directly killing species that simply can’t stand the heat.

In fact, scientists predict that if we keep going along our current greenhouse gas emissions trajectory, climate change will cause more than a third of the Earth’s animal and plant species to face extinction by 2050 — and up to 70 percent by the end of the century.

Center for Biological Diversity, 20 Dec 2008