This graph plots extinction rates of marine animal families ... perhaps enough to render the planet dark and sunless for some time. Other possible consequences have also been suggested, including ...

a mass extinction is very likely underway. The evidence is pieced together from details drawn from all over the world, but it adds up to a disturbing picture. This time, unlike the past ...

For the first time in over 10,000 years, the howl of a dire wolf is echoing once more—this time, from within a secretive ...