In 1970, the same year as "Bell Bottom Blues" hit the charts, bell-bottomed greens thronged the first Earth Day events, where they learned, chanted, sweeped—and even littered.

An undersea cleaning party and the world's largest baked alaska join the ranks of oddball events that have been held on Earth Days past to draw attention to environmental causes.

No male of the species has ever been found, but that's OK. "They appear to have evolved a new mode of reproduction," an expert says.

From a reported 270,000 sharks fished daily to 106,000 cans of soda consumed every 30 seconds, brain-boggling measures of human consumption have been made visual--just in time for Earth Day.

See the last days of a California tent city, Japanese courtesans on parade, an artist with a third "ear" on his arm, and more in our editor's picks of the week's best news pictures.

Antarctica's gushing, rust-stained Blood Falls contains evidence that microbes have survived deep under ice for perhaps millions of years, a new study says.

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.

Tropical seas sometimes blaze with the luminous green love rituals of the marine fireworm. Now scientists have been set atwitter by the industrial applications of the luminescence—and the quirky habits of the seafloor-dwelling animals that produce it.

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.

More than 70,000 beads of a surprising variety of materials, colors, and shapes have been dug out of an island along a 17th-century Spanish trade route, offering a new view of the reach of the Spanish Empire.

In a tomb like no other, the 1,500-year-old "Lord of Ucupe" has been found with 19 golden headdresses and other treasures that shed light on the little-known Moche Indians.

Have a look at a turtle with a prosthetic flipper, a sun blessing that only happens once every 28 years, and an alarming child-like robot in this week's selection of the best news photographs.

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.