2009-05-18

Scientists closer to finding origins of life  

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Scientists closer to finding origins of life

By Steve Connor


Popular theories on the origins of life have focused on the ancient ocean environment.

Scientists have developed an experiment which demonstrates how the very first life may have formed about four billion years ago.

John Sutherland and colleagues at Manchester University have broken new ground by being able to synthesise almost from scratch two of the four building blocks of RNA, the self-replicating molecule that many scientists believe to be the most likely contender for the original molecule of life.

Dr Sutherland believes that he has shown how it was possible to make all the building blocks of RNA from the simple chemicals that would have existed on Earth four billion years ago.

"We've made the building blocks of RNA from what was around on the early Earth and is still around in interstellar space and in the atmosphere of Saturn's moon Titan," Dr Sutherland said. "We haven't yet made the RNA molecule itself but we've made two of the four sub-units or building blocks. It suggests that making the molecule is possible," he said.

RNA is the less familiar cousin of DNA, the genetic blueprint of life. Like DNA, the RNA molecule can carry and transmit information from one generation to the next. But unlike DNA, RNA is a relatively simple molecule that many scientists believed could have been quite easy to synthesise in the harsh environment of the early Earth.

The trouble with this idea - which is more than 40 years old - is that no one has been able to join up the three components, the sugars, bases and phosphates that make up the four building blocks of RNA, under the sort of conditions that existed four billion years ago. Dr Sutherland, however, has shown in a study in the journal Nature that this is indeed possible.

"The trouble is, the human eye sees the three components of RNA and so the human brain assumes that to make the molecule you should combine those three components. People have found that they can make the sugars and the bases but the key thing they can't do is to join them together," Dr Sutherland said.

"We've just changed the order of assembly of the pieces, but it's overcome the dogma that it cannot be done."

In trying to explain how life began on Earth, scientists have attempted to formulate theories to account for how the first self-replicating molecule came into existence. One of the earliest theories was the "primordial soup", where simple molecules mixed together in a broth that was regularly energised by ultraviolet light and electric storms.

Over time, these molecules would have combined to form more complex substances containing the all-important ingredients of life - oxygen, carbon, hydrogen and nitrogen. Although scientists were able to make the building blocks of proteins in this way, they failed to do the same with DNA or RNA.

Thomas Cech at the University of Colorado and Sidney Altman at Yale found that RNA could act as a catalyst by speeding up a chemical reaction and yet being unchanged in the process.

This was the first hard evidence that RNA, a molecule that can replicate and store genetic information, could also have triggered the first synthesis of life's proteins.

- INDEPENDENT

Pen Hadow climate change trek finds thin ice  

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Arctic explorer Pen Hadow has warned that the polar ice cap he has been examining to gauge the extent of climate change appears far thinner than expected after trekking more than 250 miles to the North Pole.


Pen Hadow: Arctic explorer Pen Hadow warns polar ice cap 'thinner than expected'
British explorer Pen Hadow drills to measure ice thickness in the North Pole Photo: GETTY

The veteran explorer and his team trekked more than 269 miles for 73 days but were unable to make it to the North Pole because of extreme weather, with temperatures dropping below minus 40 degrees F/C.

The Catlin Arctic Survey, the first Polar expedition to monitor the affects of climate change on sea ice, was also unable to measure the ice using state-of-the art equipment because of the freezing conditions.

The average measurement was 1.77m, which is thinner than expected and suggests most of the ice formed in the last year rather than over a longer period of time.

Speaking by satellite phone before being picked up by plane, Mr Hadow said he "hardly ever" came across layers of ice more than a year old despite scientists expecting multi-year ice of 3m or more.

"Our science advisers had told us to expect thicker, older ice on at least part of the route, so it is something of a mystery where that older ice has gone," he said.

"It'll be interesting to see what scientists think about this," he said as he prepared to be flown off the Arctic Ocean ice.

But the first man to trek solo to the North Pole six years ago stressed that he was drawing no conclusion from the initial findings, saying he and his two colleagues were simply there to observe and measure.

“We have succeeded in doing our core programme of scientific work through observation and drilling,” he added.

The expedition, which is backed by the Prince of Wales, will now pass on the raw data to scientific organisations to analyse including Nasa, the University of Cambridge and the US Navy.

Mr Hadow said he was surprised to find the average ice is thinner, suggesting the ice cover will be even further reduced this summer.

The findings come as Nasa warned that sea ice cover over the Arctic reached its lowest volume since records began this year.

“The average measurement of 1.77m raises far more questions than it answers,” he said.

Mr Hadow, polar explorer Ann Daniels and photographer Martin Hartley survived in temperatures as low as minus 40F/C, but where the wind chill made it minus 94F (-70C). As well as making distance, it was necessary to spend up to four hours a day taking measurements with the manual drill in often challenging conditions.

The team was expecting to swim up to two hours a day through freezing water in full immersion suits but in fact only had to swim across open water once.

"It was too much on some occasions but we persevered," Mr Hadow said. "Those were the dark points."


French Pyrenees: bad news bears  

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Popular with conservationists, Parisians and France's first lady, brown bears have been reintroduced to the Pyrenees and infuriated sheep farmers - and their claws are out.

By Malcolm Smith
French Pyrenees: bad news bears
200-300 sheep are killed by bears and the farmers are compensated Photo: Getty Images

Softly spoken and charming, François Arcangeli is an unlikely recipient of death threats. Nor does Arbas – the tranquil and somewhat forlorn village tucked away in the foothills of the French Pyrenees 50 miles east of Lourdes where Arcangeli has been the mayor for 13 years – seem a likely location for violent demonstrations.

The cause of this unrest are brown bears.

"In spring 2006 the French government arranged for three bears from Slovenia to be released into the forests near Arbas," Arcangeli tells me. "Two others were released near other villages. Gendarmerie intelligence warned us that there might be a few protesters, mostly farmers worried about their sheep being attacked. But 250 turned up, smashing anything they could find outside the town hall, trying to break in, spraying paint and throwing bottles of blood. Eighty gendarmes tried to keep order."

The plan, agreed between Spain, France and Andorra, had been to introduce 15 bears over three years but since the Arbas riots no more have been released.

Of the five introduced in 2006, one gave birth to two cubs. But two others, both females, died. One fell from a cliff in a freak accident. The other was killed by a car on a road outside Lourdes, much to the delight of many local farmers and the sorrow of conservationists.

"We are immensely satisfied that this bear was killed. This is a great relief for farmers," Marie-Lise Broueilh, the president of the Association Inter­professionnelle du Mouton Barèges Gavarnie, an organisation promoting mountain sheep meat, commented at the time.

Bears are shy creatures, easily frightened by people. And while claims of aggressive bears are often promoted by anti-bear interests, there are virtually no records of anyone being attacked anywhere in Western Europe. So forest walking in bear country is perfectly safe. And there is little conflict with tourist developments such as ski centres because the bears hibernate in winter. And skiing takes place on higher mountain slopes above the forests and pasturelands where bears live.

More importantly, brown bears are largely vegetarian. In spring they feed on flowering plants and grasses, adding in fruits and berries during summer. In autumn, preparing for hibernation, they need to eat fat-rich foods, so acorns, beechnuts and hazelnuts figure highly. And bears really do love honey, hence their liking for wild bee nests and beehives. Honey-making is an artisan industry in the Pyrenees. But beehives are easy to protect with electric fences or by elevating hives on tripods.

Brown bears will kill other mammals for food. Powerfully built, with males weighing up to 700lb and females 440lb, and a body length of up to 8ft, they are quite capable of killing large deer. Sheep, though, are easier prey. Therein lies the source of most of the conflict.

"Of the half million sheep in the French Pyrenees, about 15,000 die naturally each year because of disease, bad weather and falls," Frédéric Decaluwe of the Office of Hunting and Wildlife, a government agency, says. "Two hundred to 300 a year are killed by bears, and the farmers are compensated."

And that compensation seems pretty generous. For a sheep worth between €20 and €100 at market, depending on its age and quality, a farmer gets €140 for each one killed by a bear plus another €140 'disturbance premium' per incident. Similar compensation schemes operate on the Spanish side of the Pyrenees.

"We usually get the compensation to the farmer within three weeks," Decaluwe says. "If there's doubt about what killed the sheep [wolves, stray dogs and even the farmers' own dogs] a commission on which farmers are represented meets at the end of each season to assess the evidence. If there is still any doubt, the compensation is paid."

Arcangeli, who is also the president of Pays de l'Ours-ADET, an organisation promoting bear conservation, thinks the farmers do well from the system.

"Before the compensation for bear kills, farmers used to complain that stray dogs killed their sheep. But they never claim that now, only bears. It's always bears," he says, laughing.

Brown bears are still reasonably common across North America, Russia and northern and central Asia. Their range once covered the whole of Europe, too. But that was before forest clearance steadily reduced their habitat. By the Middle Ages, Europe's brown bears were confined to the less accessible mountain areas. Hunting finished most of them off and they were extinct in Britain before the Norman conquest.

Today, their European stronghold is in western Russia and northern Scandinavia, where thousands still live. They fare reasonably well in some Eastern European countries such as Romania, Slovenia and Croatia.

In Western Europe, where they are strictly protected, their populations are fragmented, very small and vulnerable to extinction. Most are confined to inaccessible forested mountain ranges. In the 1930s there were perhaps 200 bears in the Pyrenees. By the mid-1990s as few as six remained, even though hunting had been banned in Spain and France. Three bears from Slovenia were introduced in 1996.

One of the few remaining native Pyrenean bears, a female, was shot trying to defend its cubs against a hunter's dog in 2004, an incident that the then French president, Jacques Chirac, called "a great loss for France and Europe" and that galvanised public opinion in favour of better protection.

In August last year Carla Bruni-Sarkozy joined the debate by writing to several environment groups, supporting the reintroduction of brown bears to the Pyrenees. "There should be no question, in our country, of choosing between bear and man," she said. 'We must find a balanced means of coexistence. On the one hand, the presence of bears in the Pyrenees reflects a willingness to protect biodiversity; on the other, the support of the local population is essential."

Pyrenean farmers will have to change the way they farm if they are to coexist with bears, and payments are available to encourage them to adapt. Most of it is channelled through local voluntary organisations and comes from the Spanish and French governments and through an EU project run by the World Wildlife Fund set up to promote the conservation of large carnivores across five European countries.

I meet Catherine Lacroix, a farmer in the tiny village of Barjac, 10 miles east of Arbas, and a founder member of the Association pour la Cohabitation Pastorale (ACP), the Association for Pastoral Cohabitation. Walking with her on her farm's lush fields framed by beech woods on the hill slopes around, it is not easy to spot the white Pyrenean mountain dog – known here as a patou – among the sheep flock.

"The patou lives out with the sheep whatever the weather, day and night," Lacroix says. 'It's here to protect the flock and if the flock is in danger, from a bear perhaps or wolves or a feral dog, the patou will become aggressive, barking loudly. They have to be brought up with the sheep as puppies and they are never treated like pets. Otherwise they couldn't do their job."

Using government grants paid by the ACP as enticement, about 200 farmers now use a patou. They receive a one-off payment of €700 once the dog has been trained to the correct standard (to offset its purchase cost plus the time to train it) and a further €250 annually.

A survey by the ACP of 37 farmers using these dogs found a reduction in the number of killed sheep by bears of more than 90 per cent. But many farmers, Lacroix acknowledges, are unwilling to accept the extra work required to train and keep a patou and are resentful that they have to change the way they manage their sheep.

Money from the EU project is also available to employ shepherds and to accommodate them in mountain huts when sheep flocks are taken up to the high summer pastures. Watching over their charges by day, with or without a patou, shepherds then round up the flock at night using a collie, often bringing them within a temporary enclosure protected by an electric fence.

Robert Wojciechowski runs a small company designing electric fences and other bear deterrents including lights, pyrotechnics and harmless lasers that can be triggered if a bear approaches. In the mountains they can be run using solar panels. Farmers buying such devices receive government grants to defray their cost.

"There are about 200 farmers in the three valleys I work in," Wojciechowski says. "Forty have bought my fences but even they are not happy knowing that they have to protect their sheep against bears. Not that it's always bears – feral dogs are just as much of a problem.

"Paris imposes bears in the Pyrenees," he continues. "They don't ask the farmers; they have no understanding of the issue from the point of view of the farmers. It's a war between farmers and bears; city people who like to think there are bears here and country people who don't want them."

Olivier Maurin, who farms 200 sheep to produce cheese at Agnos about 12 miles south-west of Pau, is typical of many. "I love bears but I don't want to have to live with them. For us farmers it's not about compensation, it's changing our way of life, our way of farming. I know we get EU subsidies to farm but we would have to get much more money before we accept bears here."

Slovenia, whose extensive forests have supplied the bears introduced to the Pyrenees, has one of the larger, more stable bear populations in Western Europe – at least a few hundred.

"People are used to living alongside bears in Slovenia," says Aleksandra Majic Skrbinšek at the University of Ljubljana, who is studying public attitudes to large carnivores (bears, lynx and wolves) in several European countries.

"Each year our government licenses a number of bears to be hunted. Most of the hunting is done by local people and they take a responsible attitude. Bears are shot for trophies and the meat is sold, so the local economy benefits. Although some people believe there should be no bear hunting, it means that country people value their bears and have a personal investment in maintaining the population.

"There is much less conflict here with farmers than in the Pyrenees. In Slovenia, sheep have always been gathered into enclosures at night to protect them. In other places where bears have been introduced, in Trentino in Italy for instance,
the state authorities talk directly to the local people about the options. In France they just talk to the local politicians and other representatives. So local people, the farmers, feel that things are imposed on them."

It isn't an argument that Frédéric Decaluwe accepts. "We try hard to talk to farmers," he says. "Every summer we have nine people outdoors doing just that. The main problem is that farmers don't want to talk about bears because they don't want bears. They say they want bears removed, not more brought here."

Nathalie Kosciusko-Morizet, the state secretary for ecology in the Sarkozy government, has made clear her determination 'to restore the population of bears in the Pyrenees in accordance with France's international obligations for biodiversity'.

"The French government has all the facts,"' Decaluwe says. "We have perhaps 20 bears in the Pyrenees.It's not a sustainable population. Our farmers are compensated well for any problems and they get EU subsidies to farm. We have a detailed action plan that includes introducing more bears. But it's all so slow. It's local politics."


2009-05-16

Gorillas are no dummies, Zoo Study Shows  

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Because gorillas (above, a young gorilla in the Democratic Republic of the Congo) rarely use tools, scientists had believed the great apes were less intelligent than their chimpanzee cousins.

But zoo gorillas demonstrate an aptitude for learning number sequences, suggesting the apes are sharper than previously thought, scientists said in May 2009s.

Gorillas Are No Dummies, Zoo Study Shows

May 12, 2009

While researchers have rigorously tested chimpanzee intelligence for years, they have paid far less attention to gorillas.

That's because gorillas rarely use tools, and scientists had assumed the great apes are not as mentally astute.

But ongoing research at the Lincoln Park Zoo in Chicago suggests otherwise.

Four years ago, scientists there attached a touch-screen computer terminal to the side of the enclosure of a female gorilla named Rollie.

As the gorilla approached, it saw the numeral one displayed on the screen. When Rollie touched the symbol, a chime sounded and the machine dispensed a frozen blueberry.

It did not take long for the gorilla to work out that pressing the number had benefits.

After a while, the computer screen presented Rollie with two symbols, the numerals one and two. Through trial and error, Rollie learned to press them in the right order to receive a blueberry.

(Related: "Monkeys Can Subtract, Study Finds.")

Chimps Lagged

Last year zoo primatologist Steve Ross reported that Rollie could sequence up to seven numbers at a time, and that chimpanzees at the facility were taking twice as long to learn the sequence.

"Gorillas rarely use tools and have rarely been cognitively studied as a result. So we did not expect them to perform very well at this," Ross said.

Despite Rollie's success, Ross and his colleagues wondered whether the gorilla was just one very sharp ape, or if such intellect could be found in other gorillas.

The scientists started testing other gorillas at their facility. The youngest of the group, a five-year-old named Azizi, is also proving to be a quick study. So far the male gorilla has only learned to sequence five numbers at a time, but has progressed as rapidly as Rollie.

In Japan similar studies are being conducted with chimpanzees, mandrills, and gibbons. None have made it past the number five.

"This is the first study demonstrating gorilla intelligence like this," said Tetsuro Matsuzawa, director of the Primate Research Institute at Kyoto University.

"I am eager to see how further research with these gorillas progresses."

Social Intolerance

The discovery raises questions about why gorillas do not use tools more often.

"We are starting to think that gorilla social intolerance blocks innovative behaviors like tool use from spreading widely through a group," said primatologist Elizabeth Lonsdorf, also at Lincoln Park Zoo.

If gorillas gathered together and studied one another—as chimpanzees do—tool use might be a lot more common, Lonsdorf noted.

(Read about chimps that hunt mammals with "spears.")

Another factor could be feeding behavior. Gorillas depend heavily on easily obtained grass and herbs that require no tools for collection, while chimpanzees commonly feed on fruits and nuts which are often hard to access without tools.

"The challenge of obtaining food may be a second reason why chimpanzees invent tools and gorillas do not," Kyoto University's Matsuzawa said.

Rare birds given own beach to ensure survival  

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A rare species of bird able to fly immediately after hatching has been given its own private beach in eastern Indonesia to help guarantee its survival.


Maleo: Rare birds given their own beach to ensure survival
Maleo, that can only be found on Sulawesi island in eastern Indonesia Photo: AP

There are fewer than 10,000 maleos, chicken-sized birds with black helmet-like foreheads, in the wild and they can only be found on Sulawesi island. They rely on sun-baked sands or volcanically heated soil to incubate their eggs.

The US-based Wildlife Conservation Society has teamed up with a local environmental group to buy a 36 acre stretch of beach in northern Sulawesi that contains about 40 nests.

John Tasirin, WCS program coordinator on the island, said it would prevent villagers digging up the eggs for food.

The maleo, which has a blackish back, a pink stomach, yellow facial skin, a red-orange beak, lays gigantic eggs that are then buried in the sand or soil.

The chicks hatch and climb from the ground able to fly and fend for themselves.

Bird species on extinction 'red list' increases to almost 200  

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The number of bird species around the world threatened with extinction has risen this year to almost 200 species despite conservation efforts, according to the latest international report.

By Louise Gray, Environment Correspondent

The International Union for Conservation of Nature's (IUCN) Red List of Threatened Species found more than 10 per cent of all bird species - a total of 1,227 - are in danger of being wiped out including birds in Britain like the red kite and curlew.

Of this, 192 bird species are listed as "critically endangered", which means they face an extremely high risk of extinction in the wild.

The number of birds in the "critically endangered" category increased by nine this year while the number downgraded to just "endangered" was seven meaning there are two more species in the more serious category.

Among those added to the list is a colourful species of hummingbird only recently discovered in Colombia, the gorgeted puffleg. Its tiny fragment of habitat, just 1,200 hectares in the cloud forests of the Pinche mountain range, is being destroyed for coca farming.

The Sidamo lark of Ethiopia has been moved from endangered up to critically endangered, as it faces the danger of becoming mainland Africa's first bird extinction due to changes in land use.

And on the 150th anniversary of the publication of Charles Darwin's The Origin of Species, which drew on evidence collected on the Galapagos, one of the islands' bird species, the medium tree-finch, has been listed as critically endangered for the first time.

The species is threatened by an introduced parasitic fly and because it has such a small, restricted range, any threat makes the bird very vulnerable, according to BirdLife International.

Simon Stuart, chairman of the IUCN's species survival commission, was disappointed more birds are "critically endangered" despite efforts around the world to protect bird habitats.

"It is extremely worrying that the number of critically endangered birds on the IUCN Red List continues to increase despite successful conservation initiatives around the world," he said.

Sourced Daily Telegraph

New species of sting ray discovered  

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Scientists have discovered a new species of sting ray, prompting concern the endangered creatures are at risk from extinction

By Cheryl-Samantha Owen
Spotted Eagle Ray swimming: New species of sting ray discovered
The spotted eagle ray is named after the numerous white ringed spots on its body and a distinctive head that resembles a bill Photo: GETTY

The spotted eagle ray was thought to be one species of fish found all over the world in tropical shallow waters including the Indian Ocean, the Pacific west coast and Gulf of Mexico.

The ray has a venomous tail but is not aggressive and feeds on molluscs. It is named after the numerous white ringed spots on its body and a distinctive head that resembles a bill. It can weigh up to 500 pounds and measure 10ft across the wingspan.

This discovery was made by a team of marine scientists from the Save Our Seas Foundation Shark Center and National Coral Reef Institute at Nova Southeastern University in Florida, USA. In the past the spotted eagle ray was categorised on its physical appearance. But using new DNA techniques, it was found the ray is actually made up of at least two and possibly more subspecies. The different species look similar but have a different genetic make up which has evolved as the ray spread to different parts of the world.

Work will now begin to officially identify and name the new species.

The findings published in the Journal of Heredity has significant conservation implications for the survival of all the new species.

At the moment the spotted eagle ray is already listed as a vulnerable and near threatened species because of its low reproductive rates.

However Mahmood Shivji from the Save Our Seas Foundation Shark Center said the different species will be even more vulnerable.

He said: "These listings are based on the designation of the ray as a single global species; in light of what we have discovered each of the more regionally distributed species may be far more threatened than previously thought. Clarifying uncertainties surrounding the number of species, and their exact distributions and population size is imperative for guiding conservation and management efforts.

For more information on the marine environment and new species' discoveries please visit www.saveourseas.com