The technique could one day be used in humans to replace glands lost through age or illnesses such as autoimmune disease and head or neck cancer.

To create the glands, Tsuji’s team extracted two types of stem cells from a mouse embryo and grew them in a mix of chemical growth factors. The cells began mimicking the interactions that occur in embryos, developing into primitive glands, which were then transplanted into adult mice that lacked salivary or tear glands.

A month later, the glands had connected with the nervous system and delivery ducts. When the researchers stimulated the digestive tracts of the mice with salt, the bioengineered glands produced saliva. Similarly, cooling their eyes made the engineered glands produce tears, complete with the proteins and lipids usually found in teary secretions.

The same team has previously grown rodent teeth and using a similar technique.

Journal reference: Nature Communications,

(Image: Syracuse University Arts & Sciences)

Inside this fruit fly reproductive tract, a battle is taking place – a battle of sperm. In turquoise are the sperm of Drosophila simulans; in orangey-red are those of the closely related Drosophila mauritiana.

of Syracuse University in New York and colleagues took this incredible snap to begin unravelling the secrets of post-sex sperm competition.

Females of promiscuous species – like the fly pictured here and many others, including our own – often mate with more than one male. As a result, the ejaculate of different males mix in the reproductive tract and the sperm cells compete to fertilise the female. But she doesn’t leave it up to them alone. She can exercise what’s known as cryptic female choice, giving some sperm an advantage over others.

The idea that animals compete for mates is commonplace, but we are only now beginning to understand post-sex competition and its influence on evolution.

Understandably, it’s difficult to observe the rivalry taking place inside the female body, and even recognising the sperm from different males is tricky. By making sperm glow in the dark, the researchers gave themselves a front-row seat to watch the sperm battle and also the chance to see cryptic female choice in action – for example, the female ejecting sperm from her reproductive tract.

Journal reference:

(Image: Stringer/Reuters)

It could be mistaken for the legendary island of Atlantis, risen once again from the depths. Shortly after a magnitude 7.7 earthquake shook south-west Pakistan on Tuesday, a muddy mound appeared in the Arabian Sea, a kilometre from the coast.

The new landmass is reported to be about 80 metres long and up to 20 metres above sea level. It was formed by a mud volcano, a jet of mud, sand and water that reached the surface after the movement of tectonic plates. The earthquake would have liquefied subsea sediment, producing a slurry that eventually ruptured the seabed and spewed out, creating the mound.

Beneath its muddy exterior, the new island also conceals gas. Rashid Tabrez, the director-general of Pakistan’s in Karachi, says there are . Heat from shifting tectonic plates caused it to expand, using gaps in the mud as escape routes. People who came to explore the island heard the hiss of escaping gas, which burst into flames when lit.

The fiery island is not likely to be permanent. It could sink back into the sea as the pressure that created it subsides, or its soft surface could be eroded away by the waves.

(Image: Gwadar Local Government Office/LANDOV/PA)

jellies (Image: Cowen Lab)

Gently gliding like spectres in the midnight black depths, these zooplankton are the subject of the latest crowdsourcing science project from the team that brought us Galaxy Zoo.

These eerie images of fantastical zooplankton were captured off the coast of southern California by an underwater robot called the . Like an ocean-based scanner, the robot casts the shadows of the tiny translucent plankton onto a high-resolution digital sensor to make these beautiful, ghostly pictures.

The project calls for online volunteers to donate some time classifying the size, orientation and type of plankton in millions of images captured by ISIIS.

The ISIIS robot works quickly: in a three-day excursion, it papped so much plankton that it would take the research team from the and three years to analyse if they were working alone. It’s no good putting a computer on the case – it could tell a shrimp from a jellyfish, but the human eye is much better at detecting the differences between intricate arrays of species from the same family.

Understanding plankton will improve our a global view of the function and health of the ocean – small they may be, but they are major players in the carbon cycle.

(Image: Linda L. Kerley & Jonathan C. Slaght/ZSL)

A golden eagle swoops down like an assassin from the sky, sinking its claws into its hefty prey – a sika deer.

The scene, which is the first documented case of such an attack, was captured at the Lazovsky State Nature Reserve in southern Russia by a . Linda Kerley from the Zoological Society of London and her colleagues working on the project were surprised to find photos of the encounter during a routine equipment check. “It’s the first time I’ve seen anything like it,” says Kerley. “It’s rare for golden eagles to snatch up deer.”

The birds of prey typically hunt other birds or small mammals but they occasionally opt for larger prey, such as coyotes. In another rare event, a golden eagle was spotted , carrying it up into the clouds where it disappeared from view. No remains were found.

Journal reference:

(Image: Mark Gee)

The Milky Way seems to mark a glowing trail from the Cape Palliser lighthouse in New Zealand to the empty expanse of the Southern Ocean in the winning image from this year’s Royal Observatory Greenwich Astronomy Photographer of the Year competition. Mark Gee’s photograph captures the otherworldly beauty of the central regions of our home galaxy, more than 26,000 light years away, as a murky mist of star-riddled dust.

The smudges on the left of the picture are the Magellanic clouds, which are even further afield. These two small galaxies, where some stars are born, are our closest cosmic companions. Long-considered to be satellites orbiting the Milky Way, this might not be the case. They might be moving across the sky because our galaxy’s gravitational pull is too weak to keep hold of them.

In Gee’s photograph, the three galaxies are suspended together overhead. “This view from the shores of New Zealand makes me think of the long voyages Maori ancestors made into unchartered oceans, guided by the stars,” says judge . “We’re in a similar situation today, as we set out to explore the universe.”

Take a look at the competition’s other prize-winning starlight snaps in our gallery.

(Images: Michel Roggo/naturepl.com)

ON RUSSIA’S far eastern coastline, the wilderness of the Kamchatka peninsula sprawls across hundreds of thousands of square kilometres. Volcanoes and geysers rise out of the landscape. Untouched by humans, this is the kingdom of the grizzly bear.

Alone in this wilderness, took these photographs by the Ozernaya river, which nourishes Kamchatka’s Kronotsky nature reserve. Their startling closeness and rare perspective are thanks to Roggo’s daring – and his waterproof camera, which he attached to a 9-metre-long pole. Laying the pole on the riverbed revealed the grizzlies hunting and devouring their catch from a viewpoint normally reserved for fish.

Despite the bears’ fearsome claws and tremendous size Roggo says he felt calm in their presence. “It is probably the most powerful moment I had in my life as a wildlife photographer,” he says. Sometimes just 5 or 6 metres from the animals, he took care not to look into their eyes or show fear. Most of his photographs – and all but the one below here – are of the same, old male bear, a dominant figure who is afraid of absolutely nothing, says Roggo.

Visiting the Kronotsky reserve is regulated and tourism strictly limited. Roggo hopes his art will help keep such ecosystems pristine the world over. His global is designed to encourage humanity to treasure them.

This article appeared in print under the headline “Grizzly camera man”

The Costa Concordia has risen from the azure waters off Italy. But how does this affect the surrounding , home to bottlenose dolphins, endangered monk seals and precious seabed life?

The ship capsized in January 2012, killing 32 people. Last week the operation to salvage the wreck, which began in May 2012, entered a key stage when the capsized hull was hauled upright via a process called parbuckling. This was done gradually to protect the ecosystem – pollutant concerns have surrounded the Concordia since the crash.

of Italy’s Tethys Research Institute says the ship probably contains toxic chemicals that could leak. “They have potential to impair an environment which is already under very strong pressure from human activities,” he says.

So far the righting operation has gone smoothly, with no apparent leaks. “A perfect operation, ” says , leader of the technical team for Costa Crociere SpA, the Italian company that owns the ship.

Noise may have had an impact, though. The salvage operation involved driving piles into the seabed, a noisy activity known to disturb and repel mammals such as dolphins.

“I don’t think that the operators are going to do anything about the noise,” says Notarbartolo di Sciara. “I also understand why – it would hugely increase the complication of the operation, and the budget.” The only way to decrease the noise pollution is to surround the operation area with a curtain of bubbles, he says.

Replanted vegetation

But Notarbartolo di Sciara is most worried about organisms that line the seabed, known as the benthos community. In this region, this includes coral, molluscs and the clam Pinna Nobilis, plus precious seabed meadows.

The seafloor was damaged when the 114,000-tonne ship ran aground, and by engineering works to rescue the wreck. “It’s going to be more serious for the bottom than for the water column unless something unexpected happens,” he says. “I don’t know how long the benthos community are going to take to come back in a state which resembles the pristine one before the accident.”

The extent of any damage will be revealed soon. Right now the ship is supported by water-filled steel boxes that have been welded to its side. Soon, water will be pumped out of these “sponsons” which, like steel armbands, will provide the ship with buoyancy, allowing it to make a final journey away from the protected Tuscan coast, in order to be dismantled.

Costa Crociere SpA hopes the Costa Concordia will be removed from the marine mammal sanctuary by mid-2014. New seabed vegetation will be planted once the wreck has been removed.

(Image: Alessandro Bianchi/Reuters)

Lying on its side in the azure waters of Giglio, Italy, the hulk of the Costa Concordia makes for a lasting reminder of the disaster that stuck the cruise ship in January 2012.

Now the ship may finally be on the move again, thanks to the most expensive salvage operation in history. The ambitious plan to right, refloat and tow away the wreckage, before dismantling it, has now reached a crucial stage: the ship is ready to be rotated off its side.

But the cruise liner poses an unprecedented challenge to the salvagers – it is teetering on the brink of a steep slope at a precarious angle. The team has already drilled into the underwater slope to once righted, preventing it from tumbling into the depths. Now, the most difficult stage of the operation is about to commence.

Hooray and up she rises

The process of heaving the enormous wreckage off its side might begin as soon as Monday, depending on the weather. Righting the ship, a technique called parbuckling, will use computer-controlled jacks to haul it upright – hopefully in one piece. The team will then assess the damage and weld on caissons – a sort of steel floatation belt – to give the ship buoyancy before it departs on its final journey.

The Concordia can’t be broken up where it lies because of the threat this would pose to the ecosystems in the Tuscan Archipelago National Park, which Giglio is a part of.

The salvage team has one chance to shift the mammoth 290-metre-long ship. With the Italian summer fading fast, the salvagers say that the weather is their worst enemy.

(Image: NASA/Wallops/Mid-Atlantic Regional Spaceport)

Is it a bird? Is it a plane? No, it’s a frog. This unfortunate amphibian met a dry, crispy end when it had a front row seat to NASA’s LADEE launch last week.

The image (click on it to enlarge it) was captured by a remote camera at NASA’s Mid-Atlantic Regional Spaceport on Wallop’s Island, off the coast of Virginia. LADEE was launched into space aboard a on its maiden voyage. The frog – also on its maiden voyage – was swept up by the ferocious roar of blast off and soared into the sky silhouetted by the fiery glow of the Minotaur V.

The would-be astronaut was probably cooling off by a pool nearby. The pool provides water for the deluge system that protects the launch pad from damage during take off and suppresses noise from the roaring rockets. The damp area probably provided a (mostly) ideal hangout for this ill-fated amphibian.

LADEE will travel much further than the frog managed: it is set to . It will take the spacecraft two and a half months to reach its target before orbiting it for 100 days.