U.S. government health regulators say a genetically modified salmon that grows twice as fast as normal is unlikely to harm the environment, clearing the way for the first approval of a scientifically engineered animal for human consumption.

The Food and Drug Administration on Friday released its environmental assessment of the AquaAdvantage salmon, a faster-growing fish which has been subject to a contentious, yearslong debate at the agency. The document concludes that the fish "will not have any significant impacts on the quality of the human environment of the United States." Regulators also said that the fish is unlikely to harm populations of natural salmon, a key concern for environmental activists.

Conservationists have expressed alarm over the low number of turtles arriving on the coast of east India and Bangladesh for the nesting season, blaming overfishing and climate change for the decline.

Between November and March, several species of sea turtle, including the Olive Ridley, travel thousands of miles to nest on the sandy shores of Sundarbans, the world's largest mangrove forest.

Outsized jaw muscles allow the black piranha to exert bite force equivalent to 30 times its bodyweight, a feat unmatched in the natural world, according to results of a finger-risking study published Thursday.

Other animals like the great white shark, the hyena and the alligator can deliver more forceful bites, but their crunching power becomes much less impressive when viewed in relation to their overall size and weight, it said.

The discovery of the Higgs Boson, an invisible particle that explains the mystery of mass, leads a list of the top 10 scientific advances of 2012 released Thursday by the U.S. journal Science.

Without the Higgs Boson, scientists believe, we and all the other joined-up atoms in the Universe would not exist.

A huge slab of sea floor near the Great Barrier Reef is in the early stages of collapse and could generate a tsunami when it finally breaks off, researchers warned Friday.

Marine geologists from Australia's James Cook University have been using advanced 3D mapping techniques on the deepest parts of the reef -- below diving depth -- since 2007 and have discovered dozens of sub-marine canyons.

The Tungurahua volcano in central Ecuador keeps spewing gas, ash and red-hot rock, forcing hundreds to evacuate from their homes.

The country's Geophysical Institute says incandescent rock shot from the crater of the 16,479-foot (5,023-meter) high mountain fell about half a mile (a kilometer) down its flanks. Explosions early Wednesday rattled windows 9 miles (14 kilometers) away, while rain-borne ash has been falling to the southwest of the crater.

Biologists say the human hand is a wonder of evolution, providing dexterity that lets our species perform activities as diverse as bricklaying, writing, ice hockey and brain surgery.

But what were the forces that, over thousands of years, sculpted our hand into the shape it is today?

A Soyuz spacecraft carrying Russian, American and Canadian astronauts blasted off on Wednesday from the Baikonur cosmodrome in Kazakhstan bound for the International Space Station (ISS).

The spacecraft took off on schedule at 1212 GMT carrying Russian Roman Romanenko, NASA astronaut Thomas Marshburn and Canadian Space Agency astronaut Chris Hadfield, an AFP correspondent said.

A U.S. appeals court ordered American anti-whaling activists to keep 500 yards (457 meters) away from Japanese whaling ships off Antarctica.

The 9th U.S. Circuit Court of Appeals issued an injunction against the Sea Shepherd Conservation Society, which sends vessels every December to disrupt whale killings by Japan's Institute of Cetacean Research.

"Twas the night before Christmas, when all through the house, not a creature was stirring, not even a mouse."

Er, not quite.