By 2100, the world will probably be hotter than it's been in 3 million years. In an interview with Yale Environment 360, paleoecologist Anthony D. Barnosky describes the unprecedented challenges that species will face in this era of intensified warming.

Hollywood has a thing for Al Gore and his three-alarm film on global warming, "An Inconvenient Truth," which won an Academy Award for best documentary.But part of his scientific audience is uneasy.

Once again, our nation has found it fitting to award the Medal of Honor to one of our brave. This is no empty act; after all, advised Churchill, it is courage that is the foundation for all other virtue.

Geysers spewing sand and dust hundreds of feet into the air have been discovered on Mars, scientists say.