Descending by plane into the Maldives offers a panoramic view of azure seas and coral-fringed islands, but as the tarmac nears, billowing smoke in the middle distance reveals an environmental calamity.

Thilafushi Island, a half-hour boat trip from the capital, is surrounded by the same crystal clear waters and white sand that have made the Indian Ocean archipelago a honeymoon destination for the rich and famous.

Human yawns are contagious for chimpanzees but, like children, this only happens among apes that have grown beyond infancy, scientists said Thursday.

Playing with a researcher, orphaned young chimps aged between five and eight years began to yawn after their human chum did so, investigators at Sweden's Lund University found.

A stunningly well-preserved skull from 1.8 million years ago offers new evidence that early man was a single species with a vast array of different looks, researchers said Thursday.

With a tiny brain about a third the size of a modern human's, protruding brows and jutting jaws like an ape, the skull was found in the remains of a medieval hilltop city in Dmanisi, Georgia, said the study in the journal Science.

An incoming comet that skygazers had hoped would provide one of the greatest celestial shows of the century, could be a fizzle.

So say astronomers tracking the eagerly-awaited Comet ISON as it races to a searing encounter with the Sun.

A British geneticist said Thursday he may have solved the mystery of the yeti, after matching DNA from two animals said to be the mythical beast to an ancient polar bear.

"We have found an exact genetic match between two samples from the Himalayas and the ancient polar bear," said Bryan Sykes, emeritus professor at Oxford University.

Palaeontologists on Wednesday said they had uncovered the earliest known complete nervous system, found in an unusual fossilized creature that lived 520 million years ago.

Measuring just three centimeters (slightly over an inch) long, the animal belongs to the megacheirans, a group of clawed marine animals that lived during the Cambrian, a time of riotous biodiversity.

Australian and New Zealand scientists Thursday said they have devised the "first rigorous framework" on deciding whether to relocate endangered animals threatened with extinction by climate change.

The researchers said it was designed to quantify whether the benefit of moving a vulnerable species outweighed the ecological cost.

Russian divers Wednesday pulled from a murky lake in the Urals a half-tonne suspected meteorite said to have been part of a meteor whose ground-shaking shockwave hurt 1,200 people in February.

The dramatic recovery operation came eight months after a piercing streak of light lit up the morning sky in the central Russian region of Chelyabinsk in scenes some locals said made them think of the onset of a nuclear war.

Australia, New Zealand, the United States, France and the EU on Wednesday stepped up pressure on Russia for a swift agreement to create vast Antarctic marine sanctuaries.

The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), comprising 24 nations plus the European Union, meet in Australia next week with Russia seen as key to protecting large swathes of the wilderness area.

Britain's only female giant panda is believed to have suffered a miscarriage, Edinburgh Zoo said on Tuesday.

It was a doubly sad day for British zoos, after London Zoo also announced Tuesday that the first tiger cub born there in 17 years had drowned.