Ruby-throated hummingbirds are migrating to North America weeks earlier than in decades past, and research indicates that higher temperatures in their winter habitat may be the reason.

Researchers say the early arrival could mean less food at nesting time for the tiny birds that feed on insect pests, help pollinate flowers and are popular with birdwatchers.

Mussels secrete a powerful adhesive to hold tight on rocks swept by violent waves -- and a synthetic version could prove critical for surgery and cancer treatment, researchers said Saturday.

Scientists have created materials that mimic the mussels' sticky proteins and could have medical applications such as sealants for fetal membrane repair, self-setting antibacterial hydrogels and polymers for to deliver cancer drugs and destroy cancer cells.

For decades, the strange substance called dark matter has teased physicists, challenging conventional notions of the cosmos.

Today, though, scientists believe that with the help of multi-billion-dollar tools, they are closer than ever to piercing the mystery -- and the first clues may be unveiled just weeks from now.

Scientists said Monday they had discovered fragments of the meteor that spectacularly plunged over Russia's Ural Mountains creating a shockwave that injured 1,200 people and damaged thousands of homes.

The giant piece of space rock streaked over the city of Chelyabinsk in central Russia on Friday with the force of 30 of the nuclear bombs dropped on the Japanese city of Hiroshima during World War II.

Biological researchers have created dead 'zombie' cells in the lab which outperform living cells.

A team at Sandia National Laboratories and the University of New Mexico have innovated a technique whereby mammalian cells are coated with silica to form a near-perfect replicas.

U.S. astronomers looking for life in the solar system believe that Europa, one of the moons of Jupiter, which has an ocean, is much more promising than desert-covered Mars, which is currently the focus of the U.S. government's attention.

"Europa is the most likely place in our solar system beyond Earth to possess .... life," said Robert Pappalardo, a planetary scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

A small army of workers is laboring to replace the estimated 200,000 square meters (50 acres) of windows shattered by the shock wave from a meteor that exploded over Russia's Chelyabinsk region.

The astonishing Friday morning event blew out windows in more than 4,000 buildings in the region, mostly in the capital city of the same name and injured some 1,200 people, largely with cuts from the flying glass.

The stunning burning-up of a meteor over Russia on Friday that unleashed a shockwave injuring hundreds of people appears to be the country's most dramatic cosmic experience since the historic Tunguska Event of June 1908.

The Tunguska Event was an explosion that went off in a remote region in Siberia on June 30, 1908, near the river Podkamennaya Tunguska in the north of current Krasnoyarsk region.

Divers scoured the bottom of a Russian lake on Saturday for fragments of a meteorite that plunged to Earth in a blinding fireball whose shockwave injured 1,200 people and damaged thousands of homes.

Scientists at the U.S. space agency NASA estimated that the amount of energy released in the atmosphere was about 30 times greater than the force of the nuclear bomb dropped on the Japanese city of Hiroshima during World War II.

What happens to fish that swim in waters tainted by traces of drugs that people take? When it's an anti-anxiety drug, they become hyper, anti-social and aggressive, a Swedish study found.

It may sound funny, but it could threaten the fish population and upset the delicate dynamics of the marine environment, scientists say.