Sponges are getting squeezed out of a distinctive role in evolution. A new study says they don't represent the oldest branch of the animal family tree after all.

The DNA research gives the spot instead to comb jellies, a group of gelatinous marine animals with names like the sea walnut and the sea gooseberry.

Below-average snow cover, melting sea ice and declines in the population of reindeers and caribou are the new normal in the modern-day Arctic, said a scientific report out Thursday.

While this year was not as extreme as 2012, the trend toward a warming planet means these changes are likely here to stay, said the Arctic Report Card 2013, issued by the National Oceanic and Atmospheric Administration.

Taking a picture to help you remember something might end up having the opposite effect, according to research published in the United States.

A study released this week showed that people who took photographs of items during a museum tour were less likely to remember details than those who merely looked at the objects.

Air flows through lizard lungs in one direction, a finding that may prompt a rethink about how some species evolved following Earth's biggest mass extinction, a study said on Wednesday.

Humans and most other animals in contrast have a so-called "tidal", or two-way, breathing system.

In response to concerns about the rise in drug-resistant superbugs worldwide, U.S. regulators Wednesday issued voluntary guidelines to help cut back on antibiotics routinely fed to farm animals.

The plan described by the Food and Drug Administration is not mandatory, and applies only to certain pharmaceuticals that are given to healthy livestock in a bid to grow bigger animals and boost food production.

NASA said Wednesday it was looking into a problem with a malfunctioning cooling pump on the International Space Station, but there was no immediate danger to the two American astronauts, three Russian cosmonauts, and Japanese astronaut on board.

A valve on a pump on one of the station's two external cooling loops shut down because it was too cool Wednesday afternoon, NASA spokesman Bob Jacobs said. He said that at no time was the crew at risk. But some non-critical equipment on the massive orbital outpost was powered down.

Japan is planning to earmark 100 billion yen ($970 million) for a storage facility for tens of thousands of tonnes of soil contaminated with radiation from the Fukushima disaster, a report said Wednesday.

The government will set aside the cash to buy some 3 to 5 square kilometers (1.2 to 2 square miles) of land somewhere near the crippled plant, the Asahi Shimbun reported.

Comet ISON, once optimistically called the comet of the century, is dead, the victim of a way-too-close brush with the sun. It was barely a year old.

The comet, which excited astronomers and the media as it zipped within 730,000 miles of the sun on Thanksgiving Day, was pronounced dead at a scientific conference Tuesday. Astronomers who had followed the ice ball mourned the loss of the sky show that once promised to light up during December.

Conservationists on Wednesday slammed Australia's approval for an Indian firm to expand a major coal port on the Great Barrier Reef coast, warning it would hasten the natural wonder's demise.

"The Great Barrier Reef is dying and (Prime Minister) Tony Abbott is hastening its death," Greens leader Christine Milne told reporters.

A nuclear war between India and Pakistan would set off a global famine that could kill two billion people and effectively end human civilization, a study said Tuesday.

Even if limited in scope, a conflict with nuclear weapons would wreak havoc in the atmosphere and devastate crop yields, with the effects multiplied as global food markets went into turmoil, the report said.