An adventure ride down a section of China's Yangtze River could be the last before planned hydroelectric dams flood the rapids and alter the landscape. Video.

Braving long walks across frigid Arctic terrain, a group of British explorers is gathering vital ground-based data about the extent of sea ice shrinkage. Video.

Iraq's southern marshes were largely restored after Saddam Hussein drained them following the 1991 Gulf War. But now a drought threatens the ancient wetlands' recovery. Video.

Cleopatra and Marc Anthony are likely buried together in one of three sites at an ancient temple, archaeologists announced in Egypt Sunday. Digging starts next week. Video.

Deliberately introduced to hunt beetles, invasive cane toad populations have exploded in Australia. Now scientists propose attacking the alien species with ants that feast on cane toad flesh.Video.

In the same Chilean town where 1,500 penguins had washed up a week and a half ago, thousands of dead sardines mysteriously tuned up on beaches. Video.

Doctors found a nearly two-inch (five-centimeter) fir tree growing inside a man's lung when they operated for a suspected tumor, Russian media are reporting. Video.

On weekends a Colombian schoolteacher straps book bags to a donkey he calls a biblioburro and travels into the countryside to lend books to eager young readers. Video.

A Brazilian mountain animal rehabilitation center nurses everything from monkeys to wolves, birds to boas. Video.

Three Sherpa brothers seek to break a time record by staying 24 hours on top. Another Sherpa may shatter his own record for most trips—19. Video.

Despite being banned in India, cockfighting continues at an annual Hindu festival. "According to tradition, once the festival is over, there should be blood stains on the festival ground," one participant said. Video.

An acoustics engineer in the U.K. claims he's got a key tool in decoding the language of dolphins. He's invented a device that visualizes dolphin sounds, but skeptics have their doubts. Video.

New reports show ice in Antarctica continues melting at an advanced rate in summer months, and ice in the Arctic region is re-forming at a slower rate in winter months.

A major earthquake struck mountainous central Italy, killing more than 90 people and leaving tens of thousands homeless. Buildings more than 500 years old in the medieval town of L'Aquila were among those damaged. Video.

As tornado season touches down in the U.S., see a high-tech tornado chaser's stunning footage of twisters—and of lightning as you've never seen it, in superslow motion.