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Archive for the ‘Environment’ Category

Genetically engineered mosquitoes pass lethal gene to offspring

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  • Scientists carry out ‘positive’ trial on Cayman Islands
  • New breed of insect could be used to tackle malaria and dengue fever
  • But critics say it could lead to public health problems

Breakthrough or danger? A UK-based research team has found a way of genetically modifying the Aedes aegypti mosquito so they pass on a deadly gene to their offspring

Breakthrough or danger? A UK-based research team has found a way of genetically modifying the Aedes aegypti mosquito so they pass on a deadly gene to their offspring

Serious concerns have been raised over the release of a new breed of disease-fighting mosquito which has been genetically engineered to kill their own offspring.

There are hopes the project could be used to control agricultural pests and tackle deadly insect-borne illnesses such as dengue fever and malaria.

But the research has raised concerns about the possible side-effects on public health and the environment because, once released, the mosquitos cannot be recalled.

A UK-based scientific team revealed there had been positive signs from the first release into the environment of the mosquitoes, which are engineered to pass a lethal gene onto their offspring, killing them before adulthood.

The study team – which includes experts from Imperial College London and the Liverpool School of Tropical Medicine – released batches of modified mosquitoes in an area of the Cayman Islands where the dengue virus-carrying Aedes aegypti mosquito is common.

The study, published in Nature Biotechnology journal, looked at how successfully the lab-reared, genetically modified insects could mate.

About 19,000 mosquitoes engineered in a lab were released over four weeks in 2009 in a 25-acre area on Grand Cayman island.

Based on data from traps, the genetically engineered males accounted for 16per cent of the overall male population in the test zone, and the lethal gene was found in almost 10 percent of larvae.

Those figures suggest the genetically engineered males were about half as successful in mating as wild ones, a rate sufficient to suppress the population.

Disease fighter? The new breed of mosquitoes could be used to tackle killer illnesses like dengue fever and malaria which affect the world's poorest populations

Disease fighter?  The new breed of mosquitoes could be used to tackle killer illnesses like dengue fever and malaria which affect the world’s poorest populations

Luke Alphey, chief scientific officer at Oxitec, the firm which devised the technique, told the BBC: ‘We were really surprised how well they did.

‘For this method, you just need to get a reasonable proportion of the females to mate with GM males – you’ll never get the males as competitive as the wild ones, but they don’t have to be, they just have to be reasonably good.’

HOW MOSQUITOES KILL THEIR OWN CHILDREN

  • The genetic approach used to create the mosquitoes is a system known as tetracycline-controlled transcriptional activation (tTA).
  • The technique is an extension of one successfully used for decades to control or eradicate pests which involves sterilising millions of insects with radiation.
  • But the process has not worked with mosquitoes, partly because the radiation also injures them, making it difficult for them to compete with healthy counterparts for mates.
  • So Oxitec has now created the Aedes aegypti mosquitoes with a gene that will kill them unless they are given the common antibiotic tetracycline.
  • With tetracycline provided in the lab, the mosquitoes can be bred for generations and multiplied.
  • Males are then released into the wild, where tetracycline is not available.
  • They live long enough to mate but their progeny will die before adulthood.

 

Authorities in the Florida Keys hope to carry out an open-air test on the modified insects as early as December after experiencing the region’s first cases of dengue fever in decades.

Dr Alphey said the technique was safe because only males were released as it was only the females that bite people and spread the disease.

But critics say the process is by no means foolproof.

Alfred Handler, a geneticist at the Agriculture Department in Gainesville, Florida, said the mosquitoes can evolve resistance to the lethal gene while being bred for generations in a lab.

Todd Shelly, an entomologist for the Agriculture Department in Hawaii, also said in a commentary published on Sunday by Nature Biotechnology that 3.5per cent of the insects in a lab test survived to adulthood despite presumably carrying the lethal gene.

Also, the sorting of male and female mosquitoes, which is done by hand, can result in up to 0.5per cent of the released insects being female, the commentary said.

If millions of mosquitoes were released, even that small percentage of females could lead to a temporary increase in disease spread, it was reported by the New York Times.

Oxitec and a molecular biologist, Anthony A. James of the University of California, Irvine, say they have developed a solution — a genetic modification that makes female mosquitoes, but not males, unable to fly.

The grounded females cannot mate or bite people, and separating males from females before release would be easier.

The World Health Organisation expects to release guidance on how GM insects should be deployed in developing countries by the end of the year.

 

Via DailyMail

12 new species of frogs discovered in India

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Scientists have found 12 new species of night frogs living in the lush mountains of southwest India, and rediscovered three that had been thought extinct.

Evolution biologist Sathyabhama Das Biju from the University of Delhi says he hopes the discoveries draw attention to amphibians as important indicators of environmental health.

He said Saturday that there are now 336 known frog species in India, and that many are threatened by habitat loss.

Night frogs are hard to find as they come out only after dark and during the monsoon season. Biju and student researchers had to sit in dark tropical forests listening for frog sounds and shining flashlights under rocks and across riverbeds.

The research is published in the latest issue of international taxonomy journal Zootaxa.

 

Via DiscoveryOn

Written by Nokgiir

September 26, 2011 at 2:19 am

The mystery creature that nobody can identify

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If this cute little chap looks a wee bit confused, it’s no wonder.

His big wide eyes stare out at the world around him – which in turn is staring back at him.

Because nobody has seen a creature quite like this one before.

Who am I? The unidentifed animal sitting in his cage after being handed in to Wenling Zoo, in China

Who am I? The unidentifed animal sitting in his cage after being handed in to Wenling Zoo, in China.

With a nose that looks more like a rodent’s but long, pointy paws and white fur dappled with brown and orange, he is quite unique.

And zookeepers at Wenling, in eastern China, who were handed the animal by an anonymous man, have been unable to work out exactly what species he belongs to.

They think they are looking at some strange type of monkey – but other students of nature might recognise the characteristics of a bush baby.

As he sits in his cage, the creature therefore awaits an uncertain fate.

And the zookeepers sit and monitor his development and hopes he grows up into something slightly more recognisable.

Where did I come from? The rodent-like creature was handed in anonymously

Where did I come from? The rodent-like creature was handed in anonymously.

Via DailyMail

Written by Nokgiir

September 26, 2011 at 1:47 am

Southern lights are sweeter in space

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NASA

The greenish glow of an auroral display sweeps around Earth’s south polar region in this photo, captured from a vantage point on the International Space Station. The shuttle Atlantis and its robotic arm, as well as one of the station’s solar arrays, loom up in the foreground.

The pilot for NASA’s last space shuttle flight, Doug Hurley, says one of the highlights of Atlantis’ trip to the International Space Station was seeing an “incredible” display of southern lights — and after seeing these pictures, I’d have to agree with him.

This photo from the space station shows the greenish auroral glow sweeping around the south pole, following the edge of the atmosphere. Atlantis is in the foreground with its robotic arm extended into the center of the frame, and one of the station’s gold-colored solar arrays juts in the right edge. You can even see the stars hanging in the night sky.

Another picture provides a more detailed view of the shimmering lights, with Atlantis’ inspection boom poking through the frame.

NASA

Thursday night’s southern lights shimmer in a picture taken from the International Space Station, with Atlantis’ inspection boom angling through the picture.

The southern lights, like the northern lights, are sparked when electrically charged particles from the sun interact with Earth’s magnetic field. For more amazing views of Atlantis’ auroras, check out NASA’s photo gallery for the shuttle mission, as well as Space.com’s report about the pictures.

 

– Alan Boyle.

‘Lost’ rainbow toad rediscovered

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Conservationists report that the Sambas Stream toad, one of their top 10 “lost” amphibian species, has been rediscovered in Malaysian Borneo 87 years after it was last sighted.

The find was made by scientists from Universiti Malaysia Sarawak who spent months looking for the toad in the remote Gunung Penrissen mountains of Western Sarawak, a natural boundary between Malaysia’s Sarawak State and Indonesia’s Kalimantan Barat Province on the island of Borneo. (Just writing those names makes me feel like Indiana Jones.)

Conservation International reports that the initial search was fruitless — so the expedition team, led by Indraneil Das, moved up to higher elevations and resumed the hunt. Eventually there came a night when one of Das’ graduate students, Pui Yong Min, spotted a small toad sitting 6 feet (2 meters) up a tree.

Das could hardly believe what he was seeing.

Indraneil Das

This picture of an adult female explains why it’s called a Bornean Rainbow Toad. The amphibian measures about 2 inches (51 millimeters) in size.

“Thrilling discoveries like this beautiful toad, and the critical importance of amphibians to healthy ecosystems, are what fuel us to keep searching for lost species,” Das said in a news release from Conservation International.  “They remind us that nature still holds precious secrets that we are still uncovering, which is why targeted protection and conservation is so important. Amphibians are indicators of environmental health, with direct implications for human health. Their benefits to people should not be underestimated.”

That’s the whole idea behind the “Search for Lost Frogs” campaign, which was launched a year ago by Conservation International and the International Union for Conservation of Nature’s SSC Amphibian Specialist Group. The groups drew up a “Ten Most Wanted” list in hopes of inspiring researchers to intensify the search for amphibians that have not been seen for decades.

The Sambas Stream toad is also known as the Bornean rainbow toad, with the scientific name Ansonia latidisca. The long-legged, multicolored toad was described by European explorers in the 1920s, and was last seen in 1924. Das’ team identified three individuals — an adult female, an adult male and a juvenile, ranging in size from roughly an inch to 2 inches (30 to 51 millimeters).

Each of the toads was found in a different mature tree, in a region of the Penrissen range that’s outside Sarawak’s system of protected areas. The precise location is being kept secret in hopes of keeping pet collectors from going after the rainbow toads.

The toads are listed as endangered on the IUCN Red List, and Conservation International said they may be eligible for protection under Sarawak’s wildlife ordinances.

Conservation International’s Robin Moore, an expert on amphibians, said he was amazed to hear of the discovery.

“When I saw an email with the subject ‘Ansonia latidisca found’ pop into my in-box, I could barely believe my eyes,” he said in the CI announcement. “Attached was an image — proof in the form of the first-ever photograph of the colorful and gangly tree-dwelling toad. The species was transformed in my mind from a black-and-white illustration to a living, colorful creature.”

Moore said he considered it a privilege to be among the first to see the pictures of the toad.

“It is good to know that nature can surprise us when we are close to giving up hope, especially amidst our planet’s escalating extinction crisis,” he said. “Amphibians are at the forefront of this tragedy, so I hope that these unique species serve as flagships for conservation, inspiring pride and hope by Malaysians and people everywhere.”

The rainbow frog is the second of the “Ten Most Wanted” amphibians to be rediscovered. The first was the Rio Pescado stubfoot toad (Atelopus balios), a species native to Ecuador that is critically endangered.

Two down, eight to go … the search continues.

 

Via MSNBC

Japan’s citizen scientists map radiation, DIY-style

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With the Japanese government only providing spotty information about the radiation leaking from the damaged Fukushima nuclear plant in the early days after the devastating March 11 earthquake and tsunami, a group of tech-minded citizen scientists set out to fill in the “black holes” in the knowledge base.

They did so by crafting their own Geiger counters and handing them out to volunteers in the disaster area to measure the fallout. Months later, they have assembled thousands of radiation readings plotted on maps that they hope will one day be an invaluable resource for researchers studying the impact of the meltdown at the crippled nuclear complex.

Volunteer Toshikatsu Watanabe, left, and Safecast’s Kalin Kozhuharov take radiation measurements in Koriyama, Japan.

The volunteer network of scientists, tech enthusiasts and residents of Japan collectively known as Safecast (an amalgam of “safety” and “broadcast”) sprang to life in the weeks after the devastating 9.0-magnitude earthquake and tsunami struck Japan, cutting off power to the Fukushima Daiichi Nuclear Power Station and knocking out its backup generators. That shut down the plant’s cooling system, triggering meltdowns or partial meltdowns in three of the plant’s four reactors, followed by explosions that released radioactive substances into the air and allowed contaminated water to leak into the ocean.

“For the scientific community, this is a huge chance to further understand what this all means,” said Pieter Franken, co-founder of Safecast and a senior researcher at Keio University in Tokyo, which is collaborating on the project. “Chernobyl was 25 years ago and delivered lots of information. But we’re now in the Internet age, and we have a huge opportunity to do a much better job in measuring it and tracking it.”

Residents in the surrounding areas were understandably alarmed, but in the early days after the disaster, information from the government came in bits and pieces, and was difficult to find.

Franken and Sean Bonner, a Los Angeles-based technology buff involved in numerous online citizen-involved projects, saw an opportunity to use technology to augment the government’s reports and to make the information widely available.

The pair found Uncorked Studios, a Portland, Ore., website development firm, which wanted to map the radiation numbers from all sources “to try to get a better picture of things on a larger scale,” Bonner said.

‘Unknowns’
The initial effort resulted in a map that revealed the dearth of information available: “We realized that there were some massive holes and that the data that was being published was not that specific,” said Bonner. “There would be one reading for an entire city. But we wouldn’t know exactly where in the city that reading was taken.”

With so many “unknowns,” the group decided to buy as many Geiger counters as possible and distribute them to people in the map’s “black holes,” Bonner said. But that wasn’t feasible because the supply of the radiation-measuring devices was limited, he  said.

So Safecast turned to a source they knew well: Hackerspaces, a loose confederation of high-tech tinkerers around the globe.

The TokyoHackerSpace had already drafted a to-do list in the disaster’s aftermath that included radiation monitoring. But with Safecast’s encouragement, the group stepped up its efforts. Members soon figured out how to build basic Geiger counters with Geiger tubes (which measure radiation) purchased through an initial fundraising campaign and modified so they could be attached to vehicles and upload data to the Internet, Christopher Wang, a specialist in sensor networks also known by his hacker nickname of “Akiba,” wrote in an email to msnbc.com.

After meeting Safecast, the hackers decided the best use of the jury-rigged devices would be to drive around taking measurements, allowing one “Geiger counter to cover a huge amount of range,” Wang wrote.

“We put together a custom circuit board that would mount on the outside of a car and had GPS (for timestamp and location data), an input for the Geiger counter, an SD card slot (for data logging), and wireless communication (to send the data inside the car and let the driver know if they are in an area with high radiation),” he said.

Other hackerspaces around the world — such as CRASH space in Los Angeles — soon enlisted in the effort and before long Safecast had the resources to launch an ambitious measuring and mapping effort.

Components of the jury-rigged Geiger counters.

While signing up volunteers, Safecast also developed a training regimen so the recruits would be able to take reliable readings with the instruments and send the data to the group.

Having average citizens involved was crucial, Franken said.

“We want to bring the radiation levels to people’s doorstep, so people can see around their house what is happening,” he said.

Safecast took its first reading on April 16. Today, it has about 50 regular volunteers who collect data from their homes or while driving, build devices or assist in other ways. Those using vehicles equipped with Geiger counters cover an area that Franken estimates to be about 620 miles long by 185 miles wide. To date, they’ve collected 251,000 data points from their drives and fixed reporting stations, and have received about 60,000 more from other sources, including people with their own Geiger counters.

Safecast publishes the data on its website and publishes it to a number of other places so the information can be used by the greatest number of people, Bonner said. It also aggregates radiation data from a number of sources, including the Japanese government.

A Safecast map shows radiation readings from northeastern Japan.

The color-coded maps that Safecast has published don’t always agree with the government’s readings. But Franken said the effort isn’t intended to suggest that the government’s information is bad. The government currently has available a website with the readings of environmental radioactivity level by prefecture.

“We really don’t want to say that the government is wrong,” he said. “And, in fact, in many cases we find that the measurements are fairly much in sync where they are comparable — we have just much more data points and locations measured.”

For example, Safecast’s mapping has revealed some radiation hotspots far from the plant, while other areas closer to it show lower levels. This is due to local weather conditions and air flow, meaning distribution of radioactive materials is not just a matter of proximity, Franken said.

“It’s not so predictable and it really pays to go and map the whole area, and literally find areas that are higher or lower as we go,” he said, noting that in some cases radiation levels can vary by street and even within a home.

“It’s kind of a heavy task because it requires a certain amount of guts to go and do it,” he said of the volunteers, noting he had recently trained a woman and her 12-year-old son in Fukushima City how to measure radiation.

Anxiety
But knowing what the levels are has helped ease some of the anxiety over the radiation exposure, Franken said.

“The measurements may or may not affect people’s decisions but in many cases we see that it more or less gives a sense of confidence that this is what it is and, ‘yeah, I’m going to stay and this is probably going to be manageable,’ or ‘no, I really don’t want to take the risk for my family, I’m going to avoid this.’”

One of the volunteers helping in the effort is Brett Waterman, a 46-year-old Australian who runs an English-language after-school program for children nearly 30 miles from the Fukushima plant, in the city of Iwaki. He has been surveying the radiation levels using a Geiger counter mounted on his car.

“There are many people who have decided that the lack of information implied that there was too much risk so they just decided to leave,” he said.

But through his work, he has learned that the radiation levels were low in the area.

“We can’t see it, but if we map it out, like we are doing street by street, we can sort of start to see it in a sense. We can get a picture of what this radiation stuff is,” he said.

His 13-year-old son is a “significant motivator” for him to take the readings. He noted that though residents don’t yet know what the long-term effects of the radiation will be, the information will be key in the future.

“In 10 years or 20 years’ time, you can’t go back to three months after the event and then find out what the data was like. But if we record it now, and then we continue to record it over the months and years to come, then from a scientific and a community point of view there is a database that can be referenced.”

Some researchers and government agencies welcome Safecast’s endeavor. Andrew Maidment, associate professor of radiology at the Hospital of the University of Pennsylvania, said the efforts were “necessary and helpful,” though he added two “cautionary notes.”

“The first is that the data are only useful, if it is clear (1) how the measurements were performed and (2) exactly where the measurements are performed,” he wrote in an email to msnbc.com. “In general, it is very easy to get erroneous measurements; consistency in following a specific protocol and lots of practice are necessary to do this right. … However, I will say that the data looks consistent since there are repeated measurements and they are spatially correlated. The second problem is that interpretation of the data is hard. Thus, the use of a color code is questionable.”

Japan’s Ministry of Education, Culture, Sports, Science and Technology did not respond to emails and a call seeking comment on the project.

The U.S. Nuclear Regulatory Commission said it was not in a position to comment on the initiative, but public affairs officer Scott Burnell noted in an email: “Speaking very generally, significant training and specialized equipment is required to provide the most accurate surveying and analysis of radioactive materials in the environment.”

Franken said Safecast encouraged dialogue with critics and supporters: “We feel that it is good to have an independent measurement available to people … I think just having more is probably better,” he said.

And Bonner said the initiative has the potential to eventually extend far beyond Japan.

“What all of this did sort of brought to light the fact that this data doesn’t exist in the quantities that it should and is not as readily available as would be helpful,” he said. “So while Japan is the focus at the moment, you know, longer term we sort of are shifting to a global outlook. There is a lot more ground to cover once everything in Japan is wrapped up.”

 

Via MSNBC/Miranda Leitsinger

Amazing photos capture split-second movements of animals leaping and flying… in a single frame

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Observing cats landing on their feet and squirrels scurrying around a garden might seem like just an ordinary event, but one talented photographer has transformed these moments into artwork.

The animal loving photographer has gone to extraordinary lengths to capture birds, rodents and insects in motion.

Using a special photographic technique that catches everything from the beat of a bird’s wing to the flick of a squirrel’s tail as it leaps through the air, Kim Taylor’s stunning photos of an animal’s ability to move from one place to another, also known as locomotion, is shown in awesome detail.

Incredible insects: A cockchafer beetle, otherwise called a may bug or spang beetle, is shot flying around the garden

Incredible insects: A cockchafer beetle, otherwise called a may bug or spang beetle, is captured flying around the garden.

Playful cats: Photographer Kim Taylor captures a white cat, named Pyramus, leaping from a chair onto a table, taken at 50 millisecond intervals

Poetry in motion: Photographer Kim Taylor captures a white cat, named Pyramus, leaping from a chair onto a table, taken at 50 millisecond intervals.

 With special homemade equipment, the 78-year-old from Surrey was able to capture his subjects in fractions of a second, giving a stunning ‘strobe’ effect on camera.

A rapidly-flashing light or strobe produces multiple images of a moving subject on a single photographic frame is a technique that has been around since the very early days of photography.

Legendary English photographer Eadweard Muybridge used this system to show the action of a galloping horse in the 1870s.

Mr Taylor was inspired to capture animals in motion by fellow Brit photographer Stephen Dalton who experimented with the technique in order to capture insects in flight.

Landing owl: A beautiful white and beige owl lands is pictured landing on a wooden post in a Surrey garden

Landing owl: A beautiful white and brown owl iis pictured landing on a wooden post in a Surrey garden.

Fluttering feathers: A European robin takes off from a wooden post as the sun sets in Surrey

Fluttering feathers: A European robin takes off from a wooden post as the sun sets in Surrey.

He said ‘I didn’t have any special equipment at the time so I had to design and build a special unit for the job.

‘This required generating dangerously high voltage – 3,500 volts – and storing the energy in a bank of special and very heavy capacitors.

‘The resulting equipment has three flash heads that flash simultaneously and produce nine flashes at rates varying from 2 per second to 500 per second.’

Playful pony: A Welsh pony and her rider a photographed galloping around some stables at half second intervals

Playful pony: A Welsh pony and her rider are photographed galloping at half second intervals.

Scurrying squirrel: A grey squirrel is captured leaping around the garden using eight images taken at 40 millisecond intervals

Leaping squirrel: A grey squirrel is captured jumping from branch to branch using eight images taken at 40 millisecond intervals.

Talented photographer: Kim Taylor from Surrey poses with his equipment Before turning to photography, Mr Taylorworked as a biologist with the Ministry of Overseas Development and later with the Ministry of Agriculture.

He received no formal training in photography or electronics but was able to learn most of what he needed to perfect his works by trial and error.

Kim said: ‘You can’t afford too many errors when dealing with a lethally high voltage, however, I am still here.

‘Because it’s very heavy, the unit does not often get taken on location, so most of the shots have been done in my Surrey garden.

‘Some of my early shots were of garden birds taking off and I had to make sure the timing was precise – just 25 to 35 milliseconds between flashes was necessary to ensure that the images were sufficiently separated.

‘I used further timing unit to ensure that the bird was already beginning to take off by the time the first strobe flash fired.

‘The shot of the robin at take off is one of my favourites but I also like the shots of insects in flight since they show how the wings are used to propel the insect into the air.

‘Digital photography and computerisation now allow series of images to be put together as if they represent a single event, whereas in reality, each image represents a separate event.

‘But genuine strobe photography shows one event as it really happened.’ Kim’s pictures are so innovative that the BBC’s One Show commissioned the photos of the squirrel which will be used on the programme this summer.’

 

Via DailyMail