From the BBC:

Global temperatures predicted for the coming centuries could trigger a mass extinction, UK scientists have warned.

The temperatures are within the range of greenhouse phases early in the Earth's history when up to 95% of plants and animals died out, they say. ...

They found that global diversity is high during cool (icehouse) periods and low during warm (greenhouse) phases.

"Our results provide the first clear evidence that global climate may explain substantial variation in the fossil record in a simple and consistent manner," said Dr Peter Mayhew of the University of York.