Interest – Page 5 – ANGFA Queensland

ANDRILL team discovers ice-loving sea anemones in Antarctica

Jan 162014

The Edwardsiella andrillae sea anemone measures less than 1 inch in length. Photo Courtesy Frank Rack, ANDRILL Science Management Office, University of Nebraska-Lincoln

News release from the University of Nebraska–Lincoln

Using a camera-equipped robot to explore beneath the Ross Ice Shelf off Antarctica, scientists and engineers with the Antarctic Geological Drilling (ANDRILL) Program made an astonishing discovery. Thousands upon thousands of small sea anemones were burrowed into the underside of the ice shelf, their tentacles protruding into frigid water like flowers on a ceiling.

“The pictures blew my mind,” said Marymegan Daly of Ohio State University, who studied the specimens retrieved by ANDRILL team members in Antarctica.

The new species, discovered in late December 2010, was publicly identified for the first time in a recent article in the journal PLoS ONE.

Though other sea anemones have been found in Antarctica, the newly discovered species is the first known to live in ice. They also live upside down, hanging from the ice, compared to other sea anemones that live on or in the sea floor.

The white anemones have been named Edwardsiella andrillae, in honor of the ANDRILL program. The discovery was “total serendipity,” said Frank Rack, executive director of the ANDRILL Science Management Office at the University of Nebraska-Lincoln and associate professor of Earth and atmospheric sciences at UNL.

When we looked up at the bottom of the ice shelf, there they were – he said.

Scientists had lowered the robot, a 4 1/2-foot cylinder equipped with two cameras, a side-mounted lateral camera and a forward-looking camera with a fish-eye lens, into a hole bored through the 270-meter-thick shelf of ice that extends more than 600 miles northward into the Ross Sea from the grounding zone of the West Antarctic Ice Sheet.

Their mission, financed by the National Science Foundation in the U.S. and the New Zealand Foundation for Research, was to learn more about the ocean currents beneath the ice shelf and provide environmental data for modeling the behavior of the ANDRILL drill string, Rack said. They didn’t expect to discover any organisms living in the ice, and surely not an entirely new species.

The discovery indicates that, even after 50 years of active U.S. research, more remains to be studied about the southernmost continent, said Scott Borg, head of the Antarctic Sciences Section in the NSF’s Division of Polar Programs.

Just how the sea anemones create and maintain burrows in the bottom of the ice shelf, while that surface is actively melting, remains an intriguing mystery,” he said. “This goes to show how much more we have to learn about the Antarctic and how life there has adapted.

Rack, who is U.S. principal investigator for the environmental surveys that were conducted as part of the international ANDRILL Coulman High project, had left the site just prior to the discovery. He was listening by radio when he heard the report from the robot deployment team — engineers Bob Zook, Paul Mahecek and Dustin Carroll — who began shouting as they saw the anemones, which appeared to glow in the camera’s light.

They had found a whole new ecosystem that no one had ever seen before,” Rack said. “What started out as a engineering test of the remotely operated vehicle during its first deployment through a thick ice shelf turned into a significant and exciting biological discovery.

In addition to the anemones, the scientists saw fish that routinely swam upside down, the ice shelf serving as the floor of their undersea world. They also saw polychaete worms, amphipods and a creature they dubbed “the eggroll,” a 4-inch-long, 1-inch-diameter, neutrally buoyant cylinder that seemed to swim using appendages at both ends of its body. It was observed bumping along the field of sea anemones under the ice and hanging on to them at times.

The anemones measured less than an inch long in their contracted state — though they get three to four times longer in their relaxed state, Daly said. Each features 20 to 24 tentacles, an inner ring of eight longer tentacles and an outer ring of 12 to 16 tentacles.

After using hot water to stun the creatures, the team used an improvised suction device to retrieve them from their burrows. They were then transported to McMurdo Station for preservation and further study.

Because the team wasn’t hunting for biological specimens, they were not equipped with the proper supplies to preserve them for DNA/RNA analyses, Rack said. The anemones were placed in ethanol at the drilling site and some were later preserved in formalin at McMurdo Station.

Many mysteries remain. Though some sea anemones burrow into sand with tentacles or by expanding and deflating the base of their bodies, those strategies don’t seem feasible for ice. It is also unclear how they survive without freezing and how they reproduce. There is no evidence of what they eat, although they likely feed on plankton in the water flowing beneath the ice shelf, Daly said.

Rack said a proposal is being prepared for further study of this unusual environment using a robot to explore deeper in the ocean and further from the access hole through the ice. NASA is helping finance the development of the new underwater robot because the Antarctic discoveries have implications for the possibility of life that may exist on Europa, the ice-covered moon of Jupiter.

He said researchers hope to return to Antarctica as early as 2015 to continue studying the sea anemones and other organisms beneath the ice shelf.

Fossil fish re-defines origins of walking

Interest

Jan 142014

Original story by Jennifer Viegas, Discovery News at ABC Science

Fossils of a creature that looked part-fish and part-limbed animal, the precursor to walking land animals, were recently found in northern Canada, according to a new study.

Color illustration of Tiktaalik swimming and walking in water. Image: Kalliopi Monoyios/University of Chicago

The beastie, Tiktaalik roseae, represents the best-known transitional species between fish and land-dwelling animals, according to researchers.

The fossil, described in this week’s edition of Proceedings of the National Academy of Sciences, lived 375 million years ago.

“Tiktaalik was a combination of primitive and advanced features,” says co-author Edward Daeschler, Associate Curator of Vertebrate Zoology at the Academy of Natural Sciences of Drexel University.

While classified as a fish, Tiktaalik looked like a cross between a fish and a crocodile. It could grow to nearly 3 metres in length, and likely spent its days hunting in shallow freshwater environments. It had gills, scales and fins, but also had features associated with terrestrial animals. These included a mobile neck, a robust ribcage and primitive lungs.

Of most interest to the researchers, its large forefins had shoulders, elbows and partial wrists, which allowed it to support itself on ground.

The presence of these limb-like features challenges the theory that such mobile hind appendages developed only after species transitioned to life on land.

“Previous theories, based on the best available data, propose that a shift occurred from ‘front-wheel drive’ locomotion in fish to more of a ‘four-wheel drive’ in tetrapods (four-footed animals),” says co-author Neil Shubin, who is a professor of Anatomy at the University of Chicago. “But it looks like this shift actually began to happen in fish, not in limbed animals.”

Some modern fish can walk, such as the African lungfish. Lungfish often look like they are slithering, more than walking, but if you see them in an aquarium, their little limbs are evident, and they do walk around.

It’s likely that Tiktaalik did the same, with its later relatives walking completely out of water and onto land, where they eventually evolved into land animals.

“Regardless of the gait Tiktaalik used, it’s clear that the emphasis on hind appendages and pelvic-propelled locomotion is a trend that began in fish, and was later exaggerated during the origin of tetrapods,” Shubin says.

Mozzie Research Creates a Buzz

Interest, research

Dec 272013

The work of Dr Nigel Beebe’s laboratory seeks to improve our understanding of mosquitoes and their role in mosquito-borne disease. Utilising strong collaborative links into the field, they integrate traditional entomological procedures with molecular genetics and informatics-based technologies to deliver new insights into vector biology and ecology. The laboratory tries to answer fundamental questions including how are species identified, which mosquito species transmit disease pathogens, where they exist and why they are there, as well as how populations connect and move.

Pacific coral changed rapidly after Little Ice Age

Interest, waterways/wetlands

Dec 182013

Original story by Tim Wall, Discovery News at ABC Science

A mysterious change in the food web of the Pacific Ocean started in the mid-19th century, and the skeletons of deep-sea coral tell the tale.

Hundreds, even thousands, of metres beneath the ocean surface, deep sea corals live for centuries. As they grow, the tiny creatures collect a chemical record of what they eat.

The deep sea corals recorded a dramatic change in the source of nitrogen entering the marine food chain. Photo: Sinniger, Oca and Baco.

Marine scientists recently constructed a 1000 year-long history of North Pacific corals’ cuisine by analysing the nitrogen trapped in the coral skeletons.

The changing levels of different types of nitrogen, called isotopes, revealed information about the conditions in the ecosystem of the North Pacific subtropical gyre, a 20 million square kilometre counter-clockwise circulation of the ocean’s waters.

For most of the past millennium, the nitrogen in the Pacific Ocean food chain came from dissolved nitrate rising from deeper in the sea. However, 150 years ago, the coral recorded a dramatic change in the source of nitrogen entering the marine food chain.

Since approximately 1850, more of the chemical has been coming from microorganisms that transform nitrogen, similarly to how beans and other legumes fix nitrogen on land. The researchers found that the level of nitrogen from microorganisms during this time increased by 17 to 27 percent.

“In comparison to other transitions in the paleoceanographic record, it’s gigantic,” says lead author of the study published in the journal Nature Owen Sherwood of the University of Colorado, Boulder.

The cause of the food chain change may have to do with an expansion and warming of the North Pacific subtropical gyre itself. Marine scientists have also observed the gyre changing again over the past few decades.

“Our new records from deep-sea corals now show that the decadal-scale changes are really only small oscillations superimposed on a dramatic long-term shift at the base of the Pacific ecosystem,” says study co-author Matthew McCarthy of the University of California at Santa Cruz.

“This long-term perspective may help us better predict the effects of global warming on open ocean regions.”

Penguin Mexican waves follow traffic rules

Interest, wildlife

Dec 172013

Original Story by Katie Silver, ABC Science

The co-ordinated way Emperor penguins move in a huddle follows the same stop-and-go movements of cars navigating their way through traffic, researchers have found.

One small move by an individual penguin affects its neighbour and creates a wave of movement that ripples through the huddle, say the researchers publishing today in the New Journal of Physics.

“A travelling wave can be triggered by any penguin in a huddle,” says co-author Dr Daniel Zitterbart from the Alfred Wegener Institute in Germany.

The findings follow more than two years of observing colonies of emperor penguins in Antarctica.

The Penguins can behave like a Mexican wave to stay warm while they move. Photo: BernardBreton/iStockphoto.

Earlier research has shown that penguins move “in a co-ordinated way, like a Mexican wave in a stadium,” according to Zitterbart.

“So if they want to move, they don’t need to break up – they can just move together.”

This means penguins can keep moving while still huddled together to keep warm.

Now, Zitterbart and colleagues have analysed time-lapse videos of male Emperor penguins to develop a model to explain what triggers this Mexican wave.

Traffic jam rules

They have found that penguins move in a similar way to cars in a traffic jam, where one small move by an individual affects neighbouring individuals, creating a wave of movement.

The researchers also found penguins move so as to find other penguins to increase their numbers – and their warmth.

In this way a group of animals can increase from roughly 100 to 3,000 penguins, Zitterbart says.

The penguins also move to find fresh water and to eliminate the gaps in their huddle.

“It’s a crystal-like structure but it’s never perfect,” says Zitterbart. “By moving closer together they help to eliminate space.”

The findings quash previous ideas that the movement is triggered by a leader, or penguins on the outer trying to push to the middle.

And if two penguins make a move at the same time, and the waves meet?

“They don’t pass each other like waves in the ocean – they merge,” says Zitterbart. “And from there on they travel as one big wave.”

But while the new research explains why penguin huddles move en masse, there are still some unanswered questions:

“We don’t know yet what actually drives them to make a step,” says Zitterbart.

But with each penguin in the huddle incubating an egg, the researchers have a theory.

“We think they use these little steps to rotate the egg while they’re in the huddle,” says Zitterbart. “We are testing it now – we will see.”

Secrets of the legless, leaping land fish

Interest

Nov 292013

A male Pacific leaping blenny on the island of Guam. Photo: Courtney Morgans/UNSW

News release from UNSW

One of the world’s strangest animals – a legless, leaping fish that lives on land – uses camouflage to avoid attacks by predators such as birds, lizards and crabs, new research shows.

UNSW researchers, Dr Terry Ord and Courtney Morgans, of the Evolution and Ecology Research Centre, studied the unique fish – Pacific leaping blennies – in their natural habitat on the tropical island of Guam.

Their study will be published in the journal Animal Behaviour.

“This terrestrial fish spends all of its adult life living on the rocks in the splash zone, hopping around defending its territory, feeding and courting mates. They offer a unique opportunity to discover in a living animal how the transition from water to the land has taken place,” says Dr Ord, of the UNSW School of Biological, Earth and Environmental Sciences.

The researchers first measured the colour of five different populations of the fish around the island and compared this with the colour of the rocks they lived on. “They were virtually identical in each case. The fish’s body colour is camouflaged to match the rocks, presumably so they aren’t obvious to predators,” says Dr Ord.

To see if background matching reduced predation, the researchers created realistic-looking models of blennies out of plasticine. “We put lots of these model blennies on the rocks where the fish live, as well as on an adjacent beach where their body colour against the sand made them much more conspicuous to predators,” says Dr Ord.

“After several days we collected the models and recorded how often birds, lizards and crabs had attacked them from the marks in the plasticine. We found the models on the sand were attacked far more frequently than those on the rocks.

“This means the fish are uniquely camouflaged to their rocky environments and this helps them avoid being eaten by land predators.”

The researchers then studied the body colour of closely related species of fish, some of which lived in the water and some of which were amphibious, sharing their time between land and sea.

“These species provide an evolutionary snapshot of each stage of the land invasion by fish,” says Dr Ord.

The similarities in colour between these species and the land-dwelling fish suggest the ancestors of the land-dwelling fish already had a colouration that matched the rocky shoreline before they moved out of the water, which would have made it easier for them to survive in their new habitat.

The Pacific leaping blenny, Alticus arnoldorum, is about four to eight centimetres long and leaps using a tail-twisting behaviour. It remains on land all its adult life but has to stay moist to be able to breathe through its gills and skin.

Watch a video of the fish leaping:

Media contacts:

Dr Terry Ord: 9385 3264 t.ord@unsw.edu.au

UNSW Science media: Deborah Smith: 9385 7307, 0478 492 060, deborah.smith@unsw.edu.au

UQ scientists discover a hidden giant

Interest, waterways/wetlands

Nov 222013

Media release from The University of Queensland

University of Queensland researchers have discovered a vivid new species of giant clam on reefs in the Solomon Islands and at Ningaloo in Western Australia.

The newly discovered giant clam. Photo: E. A. Treml.

UQ School of Biological Sciences postgraduate student Jude Keyse said the find was surprising.

“DNA sequences strongly suggest that a distinct and unnamed species of giant clam has been hiding literally in plain sight, looking almost the same as the relatively common Tridacna maxima,” Ms Keyse said.

“Giant clams can grow up to 230kg and are some of the most recognisable animals on coral reefs, coming in a spectrum of vibrant colours including blues, greens, browns and yellow hues.”

Charles Darwin University postgraduate student Mr Shane Penny, who co-authored the paper, said identifying a new species within a well-known group such as giant clams was a unique opportunity for a student.

“To correctly describe the new species now becomes critical as the effects of getting it wrong can be profound for fisheries, ecology and conservation,” he said.

Giant clams are beloved by divers and snorkelers but also prized as a source of meat and shells.

Overconsumption by humans has depleted giant clams populations in many areas and most giant clam species are on the International Union for Conservation of Nature (IUCN ) Red List of Threatened Species.

Ms Keyse said the discovery of a new species had implications for management of giant clams.

“What we thought was one breeding group has turned out to be two, making each species even less abundant than previously thought,” she said.

These results have been described today in the open access journal PLoS One, http://dx.plos.org/10.1371/journal.pone.0080858.

Media: Jude Keyse, School of Biological Sciences, +61 7 3365 7235, j.keyse@uq.edu.au.

Egret photo the people’s choice in ANZANG nature photography competition

Interest, wildlife

Nov 152013

Original story at ABC News

Sydney wildlife photographer David Stowe has won the people’s choice award in the ANZANG Nature Photographer of the Year competition.

Egret feeding, by David Stowe. Most popular pic: Little Egret, little fish. Photo: SA Museum, (c) David Stowe

The South Australian Museum said his Little Egret, little fish photo impressed many of the thousands of people who visited the exhibition in Adelaide.

What do you think of David Stowe’s image? Share your thoughts below.

Stowe expressed his delight at winning the people’s choice vote and its $500 prize.

“It means more to me than if I had won the overall prize. I was rapt to be a finalist in this competition, which is important both artistically and scientifically in celebrating the best of our wildlife,” he said.

A wedding photographer in his main work, Stowe also enjoys travelling in the outback and northern Australia to capture images of landscapes, birds and lizards.

“There are very good international wildlife photography competitions, but it’s nice to see an Australian one like this promoting what we have in this country and in the region,” he said.

“The biodiversity is just so rich and we have so much to work with.”

His winning photograph was snapped at dusk at Chili Beach on Cape York.

West Australian wildlife photographer David Rennie won the overall prize this year for his photo Near Miss.

The exhibition continues in Adelaide until November 24 and then tours Western Australia and Tasmania.

The ten weirdest fish in the world

Interest

Nov 142013

Original story at news.com.au

THERE are almost 28,000 known species of fish in our rivers and oceans, and every single one has a weird face.
There are no exceptions.
With that in mind, we’ve waded through photos of the world’s strangest fish and picked out our top ten.
Think we’ve missed one? Add your suggestions in the comments section below [registered users only].

1. THE JAWFISH

This fish hatches eggs inside its mouth to protect its newborns from predators, because that yawning chasm of a gob obviously screams safety. Don’t worry, the jawfish typically eats plankton, not human swimmers.

Open wide. Photo: Gerald Allen.

2. THE WOLFFISH

You might expect the wolffish to be a bit of a beast, especially since it can grow to more than 2 metres in length, but it’s actually pretty meek. The wolffish hides out in nooks and caves along the ocean floor, feeding on hard-shelled invertebrates such as clams. Judging from this photo, it could use a good dentist.

This fish hasn’t been flossing. Photo: Magnus Lungdren

3. THE COFFINFISH

This rather unattractive creature is found off the east coast of Australia, where it likes to occupy muddy areas of the ocean floor. It’s technically a type of “sea toad”, with a flabby body and a lure that can be hidden in its snout.

A face that even a mother couldn’t bring herself to love.

4. THE SNAKEHEAD FISH

The snakehead is a superstar on the small screen. It’s featured in TV shows like CSI: NY, Frankenfish, Swarm of the Snakehead and River Monsters. As you may have noticed, none of these programs have an optimistic vibe. But it’s not all bad. The snakehead is a delicacy in Burma and Vietnam. Eat it before it eats you, your family and your dearest friends.

Don’t put your finger anywhere near that mouth.

5. THE FANGTOOTH

The fangtooth is another scary-looking specimen, but it’s actually quite harmless to humans. The fish’s name comes from its “fanglike” teeth, which are disproportionately large in comparison to its tiny body. So why does the fangtooth have such a cranky face? Our best guess is short fish syndrome.

Grrrrrrrrrrr. Photo: AAP

6. THE PARROTFISH

This fish is disgusting. Some parrotfish species protect themselves at night by secreting a “mucus cocoon” before going to sleep. The cocoon surrounds the fish and masks its scent, which is all well and good, but then you remember that said cocoon is made of MUCUS. Imagine snorting yourself a snot blanket at night.

They call this one the parrotfish because it has a “beak”. They’ve missed the point. Photo: George Stoyle

7. THE STONEFISH

Rocks can be dangerous if thrown really hard at someone’s face, but they’re nothing compared to fish that look like rocks. The stonefish is one of the most venomous fish in the world, and it’s right on our doorstep. Stonefish venom can even be fatal to humans if left untreated. So, mind your step.

Silent and deadly. So silent in fact that you could mistake it for a rock. Photo: News Limited

8. THE GOBLIN SHARK

Whoever called this creature the goblin shark was being kind. The fish has a long, flat snout sticking out of its head, which is a teensy bit strange, aesthetically speaking. Luckily, the snout grows proportionally smaller as the shark ages, in much the same way that a human male’s embarrassingly large ego tends to shrink as he gets older.

Introducing the Frankenstein of sharks. Photo: News Limited

9. THE ANGLERFISH

Beyond Australia this creature is called a frogfish, which doesn’t make any sense to us, because this particular specimen looks more like the fluorescent hallucination of a sixties hippy. Admittedly, only certain types of anglerfish are this trippy.

Woah, trippy. Photo: David Hall/Seaphotos

10. THE BLOBFISH

Blobfish may look absolutely miserable, but he’s managed to turn himself into a Twitter star. Not a bad effort, considering this fish was just voted the ugliest animal on the planet. We think he was hard done by. Come on, look at that slimy, innocent face and tell us your heart doesn’t melt, even a little.

The Blobfish lives off the coast of Australia.

Sea slug mating features a stab in the head

Interest

Nov 142013

Original story by Susan Milius, Science News

Newly discovered hermaphroditic sea slug deploys specialized needle-thin organ for injections near the eyes.

HEAD SHOT Two tiny hermaphroditic sea slugs position for mutual simultaneous sperm transfer, but add a second connection, head to head. Photo: Johanna Werminghausen

A newly discovered sea slug adds that special something to mating: simultaneous forehead piercing.

Found on Australia’s Great Barrier Reef, the new species of hermaphroditic sea slug — bright yellow, red and white and just a few millimeters long — has the double set of penile organs typical of Siphopteron slugs. Yet the new slugs deploy them in a novel way, says marine behavioral ecologist Rolanda Lange of Monash University in Clayton, Australia.

When the as-yet-unnamed slugs mate, one organ delivers the sperm to the female opening on another slug’s body. Seconds after partners position their structures for simultaneous sperm transfer, the slugs each insert a second organ, a needlelike stylet. Each slug plunges it like a syringe into the area around the other’s eyes, Lange and her colleagues report November 12 in the Proceedings of the Royal Society B.

The slugs about to be injected don’t dodge out of the way. “Maybe they’re preoccupied with inserting their own stylet,” Lange says. The stylets, throbbing in slow pulses, stay inserted for most of the 40 minutes or so of sperm transfer.

In the matings that Lange observed, all slugs stabbed their partners in the head, rather than a different body zone or a mix of targets as related slugs do. This head strike drives the stylet into the region of the slug’s central nervous system, and the slow pulses pump compounds from one slug into the other.

Just what the slug (for now called Siphopteron species 1) gains by such injections isn’t clear yet. There are many other species of animals that slip their mating partner manipulative compounds. These biochemicals make the partner invest extravagantly in egg production, for example, or make the partner slow to accept the next mate or simply reduce the chances that sperm will get digested for nutrition instead of used for babies.

Partner manipulation “seems to be part and parcel of the mating ritual in many, if not most, hermaphroditic animals,” says evolutionary biologist Menno Schilthuizen of Leiden University in the Netherlands. In July in PLOS ONE, he and his colleagues described an Everettia snail from Borneo with the first example of what’s called a love dart — a device that delivers manipulative compounds in snail mating — that has hollow inner channels. Unlike other snails that fire these love darts, chemical-coated calcium spikes, into each other during sperm transfer, the Everettia snail has evolved darts with internal fluid-carrying channels that create natural hypodermic needles.

Snail love darts don’t strike a consistent target region as the Siphopteron species 1’s stylet does. The new paper focuses on the consistent forehead targeting but what Schilthuizen finds more exciting is the paper’s observation that species 1 and four otherSiphopteron slugs differ considerably in injection sites. “Copulatory injection itself is widespread,” he says, but “its manner varies as much as all other things sexual.”

LINKED IN Two hermaphrodite Siphopteron slugs — only a few millimeters long — mate. The heads have a shieldlike structure, and two winglike flaps curl around their sides. Mating starts with intertwining when each partner sticks out a penis. Then the slugs insert the penis into an opening on the right side of the partner and then drive sharp stylets into each other’s foreheads.

Credit: Rolanda Lange, Johanna Werminghausen, Nils Anthes

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