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Another form of life based on Arsenic?

December 2, 2010
The Arecibo message as sent 1974 from the Arec...

The Arecibo message as sent 1974: image via Wikipedia

The Telegraph  has an eye-catching headline (naturally):

‘Life as we don’t know it’ discovery could prove existence of aliens

But even without the exaggerations and the splash headlines, the possible existence of a form of life intimately connected with Arsenic would have enormous consequences on the definition and abundance of life in the universe and on how to go about searching for extra-terrestrial life.

NASA has sent the internet into a frenzy after it announced an “astrobiology finding” that could suggest alien life exists – even on earth.

The discovery could prove the theory of “shadow” creatures which exist in tandem with our own and in hostile environments previously thought uninhabitable. The “life as we don’t know it” could even survive on hostile planets and develop into intelligent creatures such as humans if and when conditions improve. In a press conference scheduled for tomorrow evening, researchers will unveil the discovery of a microbe that can live in an environment previously thought too poisonous for any life-form to survive.

The bacteria has been found at the bottom of Mono Lake in California’s Yosemite National Park which is rich in arsenic – usually poisonous to life.

Somehow the creature uses the arsenic as a way of surviving and this ability raises the prospect that similar life could exist on other planets, which do not have our benevolent atmosphere. Dr Lewis Dartnell, an astrobiologist at the Centre for Planetary Sciences in London, said: “If these organisms use arsenic in their metabolism, it demonstrates that there are other forms of life to those we knew of. “They’re aliens, but aliens that share the same home as us.”

The Brisbane Times reports:

The US space agency has created a buzz with its announcement of a press conference early tomorrow morning (Australian time) to discuss a scientific finding that relates to the hunt for life beyond the planet Earth.

“NASA will hold a news conference at 2pm EST (6am AEDT) to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life,” it said on its website.

But Nasa has declined to elaborate further on the topic, other than to say astrobiology is the ”study of life in the universe, including its origin and evolution, where it is located and how it might survive in the future”. The vague announcement has sent the blogosphere in a flurry of speculation about its potential meaning.

Blogger Jason Kottke tipped NASA would announce the discovery of arsenic on Titan, or possibly chemical evidence of bacteria utilising it for photosynthesis.

That speculation was quickly picked up and repeated by a number of other bloggers and internet sites. However Kottke theory has been rebuffed by Alexis Madrigal, senior science writer for The Atlantic, who tweeted that he had read the Science article relating to the Nasa announcement. ”I’m sad to quell some of the @kottke-induced excitement about possible extraterrestrial life. I’ve seen the Science paper. It’s not that,” he tweeted.

The American Association for the Advancement of Science, which publishes the journal in which the research will appear, told ABC News in the US that it had received numerous inquiries about the “mostly erroneous online and/or tabloid speculation about the forthcoming research”.

For NASA TV streaming video and downlink information, visit: http://www.nasa.gov/ntv at 2pm EST today (2nd December).

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Posted in Astronomy, Biodiversity, Biology, Space | Comments Off on Another form of life based on Arsenic?

Paraguay suspends Natural History Museum’s “genocide” expedition

November 16, 2010
Very approximate location of the Gran Chaco (U...

Gran Chaco area: Image via Wikipedia

I posted a few days ago about the dangers of the Natural History Museum’s planned 60 – 100 strong “expedition” to the forests of Paraguay.

Today comes news that on Monday Paraguay suspended a British scientific expedition into the remote Chaco woodlands after indigenous rights groups raised concerns over the welfare of protected tribes in the region.

Sponsored by Britain’s Natural History Museum, the 45-member British-Paraguayan expedition planned to conduct a month-long survey of animal and plant life in the sprawling savanna 800 kilometers (500 miles) north of Asuncion, the ministry said in a statement.

The decision to suspend it followed “last minute” concerns raised by indigenous rights groups including Iniciativa Amotocodie, and recommendations by the Washington-based Inter-American Human Rights Commission, the environment ministry said.

“The massive presence of about 60 researchers in the land inhabited by the Ayoreo tribal groups in the remote, northern reaches of Chaco… poses significant risks to their lives and territory,” Amotocodie said in a statement.

The rights groups argued that since the tribes have had very little contact with the outside world they are at risk of contracting diseases that in some cases could prove fatal.

It would have been far better if the Natural History Museum had itself suspended the expedition and had taken the initiative to carry out the consultations which it is now forced to conduct.

Seattle pi:

Paraguay denied authorization Monday for a British-led scientific expedition to catalog plants and animals in the country’s remote northern corner, saying there isn’t enough time to consult with relatives of nomadic Indians who try to remain isolated as they pass through the area.

The non-governmental Amotocoide Initiative, an advocacy group for native Ayoreo Indians who live in the dry forests of northern Paraguay, had warned that scientists might carry European diseases to the Indians, leave trash or otherwise suffer violent encounters.

Isabel Basualdo, director of the biodiversity office of Paraguay’s environmental ministry, said in a statement that the decision follows the recommendation of the Interamerican Human Rights Commission that public hearings and all other legal requirements are complied with before such a visit.

Richard Lane, the British Natural History museum’s director of science, said the expedition had been suspended while consultations take place. “We believe that this expedition to scientifically record the richness and diversity of the animals and plants in this remote region is extremely important for the future management of this fragile habitat,” Lane said in a statement.

But some anthropologists who advocate for the Ayoreos say no outsiders should enter these dry forests, where small bands of people are still trying to live in isolation from the modern world. Irene Gauto, who represents the private environmental group Guyra Paraguay, told The Associated Press that the environment ministry “sent a letter to the British museum arguing that, for now, it’s better to delay the visit of the scientists because there hasn’t been time enough to hold public hearings with the relatives of the forest-dwelling Ayoreos,” one of 20 surviving indigenous groups living in Paraguay.

The trip was to begin Saturday to the Chovoreca and Cabrera-Timane hills near Paraguay’s border with Bolivia and Brazil, about 500 miles (800 kilometers) northeast of the capital. The scientists planned to catalog species on a private cattle ranch within a Paraguayan nature reserve. The ranch’s owners approved the trip and said indigenous people didn’t live there, Gauto said.

The government appeared ready to approve the trip. But the situation changed after a leader of the Totobiegosode subgroup of Ayoreos, Chiri Etacori, said about two dozen nomadic Ayoreos wander through the area.

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Sterile, male, GM mosquitoes released to fight Dengue

November 12, 2010
Ochlerotatus notoscriptus, Tasmania, Australia

Image via Wikipedia

PhysOrg.com:

Scientists have released genetically modified mosquitoes in an experiment to fight dengue fever in the Cayman Islands, British experts said Thursday.

It is the first time genetically altered mosquitoes have been set loose in the wild, after years of laboratory experiments and hypothetical calculations. But while scientists believe the trial could lead to a breakthrough in stopping the disease, critics argue the mutant mosquitoes might wreak havoc on the environment.

“This test in the Cayman Islands could be a big step forward,” said Andrew Read, a professor of biology and entomology at Pennsylvania State University, who was not involved in the project. “Anything that could selectively remove insects transmitting really nasty diseases would be very helpful,” he said.

Dengue is a potentially fatal mosquito-borne disease that can cause fever, muscle and joint pain, and hemorrhagic bleeding. More than 2.5 billion people are at risk and the World Health Organization estimates there are at least 50 million cases every year. There is no treatment or vaccine.

Unlike malaria, which is also spread by mosquitoes, dengue outbreaks are unpredictable and bed nets are of limited use because dengue-spreading mosquitoes also bite during the day.

Researchers at Oxitec Limited, an Oxford-based company, created sterile male mosquitoes by manipulating the insects’ DNA. Scientists in the Cayman Islands released 3 million mutant male mosquitoes to mate with wild female mosquitoes of the same species. That meant they wouldn’t be able to produce any offspring, which would lower the population. Only female mosquitoes bite humans and spread diseases.

From May to October, scientists released batches of genetically mutated male mosquitoes in cages three times a week in a 40-acre (16-hectare) area. By August, mosquito numbers in that region dropped by 80 percent compared with a neighboring area where no sterile male mosquitoes were released.

Luke Alphey, Oxitec’s chief scientific officer, said with such a small area, it would have been very difficult to detect a drop in dengue cases. But their modeling estimates suggested an 80 percent reduction in mosquitoes should result in fewer dengue infections.

Yeya Toure, who leads the World Health Organization’s team on Innovative Vector Control Interventions, called the Cayman Islands trial promising and said it’s worth continuing the genetic modification experiments. He said genetically altered mosquitoes aren’t meant to replace existing tools like insecticides, but to compensate for their limitations, like when mosquitoes develop resistance.

Read said creating mutated mosquitoes might actually be the least invasive way to control dengue. By keeping a lid on the mosquito population via genetic modification, Read said entire ecosystems would be spared the toxic effects of indiscriminately spraying pesticides.

Of course opponents of GM (Gene Modification) think this may be a “bad thing” even though the GM modified males cannot last more than a generation.

“If we remove an insect like the mosquito from the ecosystem, we don’t know what the impact will be,” said Pete Riley, campaign director of GM Freeze, a British non-profit group that opposes genetic modification.

He said mosquito larvae might be food for other species, which could starve if the larvae disappear. Or taking out adult mosquito predators might open up a slot for other insect species to slide in, potentially introducing new diseases.

Experts in the safety of genetically modified (GM) organisms have expressed concern over the release of GM mosquitoes into the wild on the Cayman Islands, which was publicised internationally only last month — a year after their initial release.

Ricarda Steinbrecher, a geneticist and co-director of EcoNexus — a UK-based non-profit research organisation — expressed surprise that the trials had occurred, saying that they had not been mentioned at the fifth meeting of the Parties to the Cartagena Protocol on Biosafety — which addresses international safety issues relating to GM organisms — in Nagoya, Japan, last month. She described the lack of publicity surrounding the trials as ‘worrying, both from the scientific perspective as well as public participation perspective’. Steinbrecher said that until a full, long-term environmental assessment of the Cayman trials has been carried out, the recently announced Malaysian trials of the same strain should not go ahead.

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Posted in Biology, Development, Ethics, Medicine | Comments Off on Sterile, male, GM mosquitoes released to fight Dengue

Natural History Museum expedition could mean “genocide” for indigenous people

November 8, 2010

From The Telegraph:

The Natural History Museum has been warned that a forthcoming trip to find hundreds of new species in the remote forests of Paraguay could risk the lives of indigenous people and the scientists.

The 100-strong expedition, one of the largest undertaken by the museum in the last 50 years, is due to set off in the next few days to explore one of the most unknown regions of the world for one month.

However the museum has been warned by campaigners that the trip could cause “genocide” for isolated tribes.

The group Iniciativa Amotocodie, that protects local indigenous people, said groups of Ayoreo Indians in the area have never come into contact with westerners before. If they come across the expedition without preparation they could catch common western viruses that could wipe out the small groups in a matter of weeks.

A statement from the group, that has been circulated online, read: “If this expedition goes ahead we will not be able to understand why you prefer to lose human lives just because the English scientists want to study plants and animals. There is too much risk: the people die in the forest frequently from catching white people’s diseases – they get infected by being close. Because the white people leave their rubbish, their clothes, or other contaminated things. It’s very serious. It’s like genocide.”

The vast area of dry forest across parts of Bolivia, Argentina as well as Paraguay, known as the Gran Chaco, is the only place in South America outside the Amazon where there are uncontacted tribes. Until about 1950 it was thought there were around 5,000 people in the area but now there are thought to be less than 150 as people leave or die out.

Richard Lane, Director of Science at the NHM, confirmed that he had received a letter from a group representing indigenous groups. “Clearly the needs of indigenous people to remain uncontacted needs to be respected and we as an institution have always respected that,” he said.

With a hundred people involved in this expedition and tramping through the jungle it is hardly a case of  being very discreet or showing very much respect for the indigenous tribes. (Does it really take one hundred people? Explorers used to go in twos.)

The naming of new species of plants in the name of protecting biodiversity seems to be rather more important than the lives and the way of life of these unfortunate tribes. That a body such as the Natural History Museum is prepared to risk genocide for the sake of finding and naming species that have not been recorded is astonishing. The species will carry on very well even if they receive no names and will probably be better off for not having any contact with the expedition (or perhaps circus would be more accurate).

The Natural History Museum would be well advised to cancel this vacation in the jungle or at least to reduce the numbers in the expedition to about two.

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Posted in Behaviour, Biodiversity, Biology, Environment, Evolution, Social Science | 2 Comments »

A special gene for camouflage

November 1, 2010

C. Zhang, Y. Song, D. A. Thompson, M. A. Madonna, G. L. Millhauser, S. Toro, Z. Varga, M. Westerfield, J. Gamse, W. Chen, R. D. Cone. Inaugural Article: Pineal-specific agouti protein regulates teleost background adaptation. Proceedings of the National Academy of Sciences, 2010; DOI: 10.1073/pnas.1014941107

Science Daily

 

Like other bony fish, the peacock flounder can change the color and pattern of its skin to blend into the sea floor. (Credit: Photo by Jimmie Mack)

 

Researchers led by Vanderbilt’s Dr. Roger Cone have discovered a new member of a gene family that has powerful influences on pigmentation and the regulation of body weight.

The gene is the third member of theagouti family. Two agouti genes have been identified previously in humans. One helps determine skin and hair color, and the other may play an important role in obesity and diabetes. The new gene, called agrp2, has been found exclusively in bony fish, including zebrafish, trout and salmon. The protein it encodes enables fish to change color dramatically to match their surroundings, the researchers report this week in the early edition of theProceedings of the National Academy of Sciences (PNAS).

“When my graduate student, Youngsup Song, discovered a third agouti protein in the fish pineal gland, an organ that regulates daily rhythms in response to light, we initially thought we had found the pathway that regulates hunger diurnally,” said Cone, chair of the Department of Molecular Physiology & Biophysics and director of the Vanderbilt Institute for Obesity and Metabolism.

“That is the mechanism that makes you hungry during the day, but not at night,” he continued. “However, Chao Zhang, a graduate student who followed up the study, ultimately discovered that this agouti protein … is involved in the rapid pigment changes that allow fish to adapt to their environment.”

This phenomenon, called background adaptation, also has been observed in mammals. The coat of the arctic hare, for example, turns from brown in summer to white camouflage against the winter snow.

In contrast to mammals that have to grow a new coat to adapt to a changing environment, fish, amphibians and reptiles can change their skin color in a matter of minutes. The first agouti gene, which produces the striped “agouti” pattern in many mammals, was discovered in 1993. The same year, Cone and his colleagues at Oregon Health Sciences University in Portland reported the discovery of the gene that encoded the melanocortin-1 receptor, a key player in the pigmentation story.

In the current paper, Cone’s group reports that the newly discovered protein, AgRP2, regulates expression of the prohormone genes pmch and pmchl, precursors to melanin-concentrating hormone, which has a pigment-lightening effect. “Together, the versatile agouti proteins and melanocortin receptors are responsible for regulation of body weight, the banded patterns of mammalian coats, and even red hair in most people,” Cone said. The current work shows that agouti proteins are also involved in the camouflage mechanisms used in thousands of fish species.

Read the article.

If only the gene could be activated in humans as well!!!

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Posted in Biology, Evolution, Medicine, Science, Wildlife | 1 Comment »

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