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Cosmic Dust Could Form Inorganic Life, Study Suggests

Posted by MAHANEESH | Posted in | Posted on 10:27 AM

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A recent study suggests that dust in interstellar space can arrange itself into structures that resemble inorganic life-forms.
According to a team of Russian scientists, lifelike behavior could occur in certain configurations of plasma—a state of matter composed of electrically charged atoms.
The claim has drawn mostly baffled, and skeptical, responses from physicists and alien-life experts.
Vast, diffuse clouds of dust and plasma are prevalent throughout the universe. (See a National Geographic magazine feature on "Dust in Space".)
Using computer simulations, a team led by Vadim Tsytovich, of Russia's General Physics Institute in Moscow, found that under certain conditions dust and plasma can organize into stable, helix-shaped structures resembling DNA.
While the structures exhibit none of the complex chemistry associated with even the simplest forms of life on Earth, they appear to at least mimic some the basic processes associated with living systems, the team said.
For example, the helical strands were sometimes capable of reproducing by splitting and reassembling into two identical copies.
The structures also exhibited a kind of evolution, according to the researchers.
Structural changes that took place in the strands were passed from one "generation" to the next, the researchers said. As conditions changed, only the most stable configurations were able to persist.
Because of these and other characteristics, Tsytovich's team argued that the dusty plasma structures should be considered a form of inorganic life.
"It appears from our numerical simulations that large assemblies of … dusty plasmas may satisfy the commonly accepted minimum conditions used to define life," said co-author Gregor Morfill of the Max Planck Institute for Extraterrestrial Physics in Germany.
Morfill said that while the results were based on computer models, lifelike plasmas may one day be discovered in space.
"[Given] a sufficient concentration of charged dust, the process of self-organization and growth can be triggered," Morfill said.
"My best guess as to where such systems could develop would be the quiet and benign environment inside interstellar dust clouds," he added.
The study appeared in the August issue of the New Journal of Physics.
Dust to … Life?
Other scientists are skeptical that space dust may form a kind of inorganic life. All life on Earth is considered organic, or carbon-based.
Several researchers declined to comment on the record but suggested the claim of lifelike behavior exhibited by the material was highly speculative.

But Mihaly Horanyi, a plasma physicist at the University of Colorado, said the behavior of the structures is "amazing," regardless of whether they are classified as truly living.
"I trust that the physics is sound," Horanyi said. "You could reproduce these results experimentally.
"At some level the statement [that the structures may be forms of life] is almost tongue in cheek," Horanyi said.
"It's more a philosophical question—how do you define life?
"This is a very original, very intelligent paper that will trigger a lot of debate," Horanyi added.
Co-author Morfill said that such a debate was exactly the researchers' goal.
"It all comes down to a definition of life, and there the experts will need to come to terms with other issues as well," Morfill said.
"Since these are only definitions, which can be changed, I hesitate to call these systems life myself. I prefer to view our results as an interdisciplinary, thought-provoking trigger for further research." Undergoing MyBlogLog Verification

Building Blocks of Life Detected in Distant Galaxy

Posted by MAHANEESH | Posted in | Posted on 10:22 AM

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The discovery of an amino acid precursor in a far-flung galaxy is fresh evidence that life has potential to form throughout the universe, scientists say.
Researchers using the world's largest radio telescope—the Arecibo Observatory in Puerto Rico—have detected methanimine in the distant galaxy Arp 220.

Researchers had previously detected evidence of formaldehyde, ammonia, hydrogen cyanide, and possibly formic acid in the star-forming region.
Methanimine can form the simplest amino acid, glycine, when it reacts with either hydrogen cyanide and then water, or formic acid.
"The fact that we can observe these substances at such a vast distance means that there are huge amounts of them in Arp 220," said Emmanuel Momjian, a former Arecibo astronomer, now at the National Radio Astronomy Observatory in Socorro, New Mexico.
"It is indeed very intriguing to find that the ingredients of life appear in large quantities where new stars and planets are born."
The scientists warn, however, that Arp 220 has undergone a recent merger and hosts a vibrant star nursery. With new stars living hot and fast, then violently exploding, conditions are probably too turbulent to allow life to evolve.
But the ingredients for life could take root later, when more stable, sun-like stars are born. (Related: "Newborn Planet Found Orbiting Young Star" [January 3, 2008].)
Hitting the Jackpot
The new discovery came during the first of two summers that scientists spent surveying Arp 220's composition using the Arecibo telescope. The details of the find were unveiled at last month's meeting of the American Astronomical Society in Austin, Texas.
Chris Salter, an Arecibo astronomer, likened the chemical survey to a "treasure hunt" that hit gold on the very first night of observing.
Methanimine has been previously detected in our own galaxy and tentatively in the nearby galaxy NGC 253, "but never beyond the neighborhood," he writes with his co-authors in a paper that has been submitted for publication in the Astronomical Journal.
While studying the survey data, co-authors Tapasi Ghosh, an Arecibo astronomer, and Mayra Lebron, a former Arecibo astronomer now at the University of Puerto Rico "said, Something looks an awful lot like a spectral line here, and we said, Pull our other leg," Salter told National Geographic News.
"Slowly, we became convinced."
The team has also looked for direct evidence of glycine but has seen none of its telltale chemistry.
To date, more than 140 molecules have been identified in space, mostly in the neighborhood of the Milky Way. (Get a Milky Way wallpaper.)
Prebiotic Soup
Esteban Araya is an astronomer at New Mexico Tech in Socorro and the National Radio Astronomy Observatory.
He said the discovery of methanimine in Arp 220, along with "abundant circumstantial evidence, such as the short time it took life to appear on the early Earth, suggest that life ... may be quite common in the universe."
Moreover, he said, the discovery shows complex organic molecules can exist in very inhospitable environments, such as starburst regions.
The shake-ups during rapid star formation probably created the molecules in the first place—but the chance that they'll yield complex life in such a wild scene is low, Araya pointed out.
"Nevertheless, it is possible that some of the methanimine ... will be trapped in dust grains and will enrich the interstellar medium of Arp220," he said.
"When the tumultuous present activity of Arp220 settles down, new generations of stars like our sun may be formed, and some of the organic molecules trapped in dust grains may enrich newly formed planets."
(Related: "Many 'Earths' Are Out There, Study Says [April 6, 2005].)
Rallying Cry for Arecibo
Astronomers predict that the new discovery will touch off new observation programs at the world's largest radio telescopes, including Arecibo, the National Radio Astronomy Observatory's Green Bank Telescope in West Virginia, and the Very Large Array in New Mexico.
Heightened interest in what such scopes can offer the search for extraterrestrial life will be a shot in the arm for Congressional funding that has been waning, the researchers hope.
Arecibo, in particular, has appeared headed for closure if proposed funding cuts materialize.
"These findings show how important Arecibo Observatory can be for the search of biologically important molecules in space," said Héctor Arce, an astrophysicist at Yale University.
"If Arecibo was able to detect molecules from a galaxy [250 million light-years] away, imagine its potential for searches of complex molecules in our own galaxy."
Salter and his colleagues do have plans to turn Arecibo's power toward the Milky Way—if they can.
Meanwhile, they're pushing ahead with the remainder of their Arp 220 survey.
With a little more analysis, they say, they can be more certain about preliminary evidence that methanol—another organic molecule of interest—can also be found in the galaxy.
And they're eager to tackle a list of 20 other starburst galaxies within reach of the telescope, which could contain similarly exciting molecules, Salter said.
"We are hoping to show that Arp 220 isn't that much of an oddball."

Amazon Expedition Discovers Dozens of New Animals

Posted by MAHANEESH | Posted in | Posted on 8:12 AM

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Sporting a flashy pattern of lavender on black, this newfound species of toad is among two-dozen animals that scientists discovered recently in the highlands of the northern Amazon.Among the new creatures are four frogs, six species of fish, a dozen kinds of dung beetles, and a type of ant never before seen by scientists.Researchers made the finds during a survey of remote plateaus in eastern Suriname from 2005 to 2006 (see map of Suriname).Two mining companies sponsored the research, which was conducted by the nonprofit group Conservation International (CI), to determine the diversity of wildlife in the area before it undergoes further development. Though secluded, the region has already felt enough pressure from human activity to drive some animals to near extinction. One of the expedition's welcome surprises was the re-discovery of an armored catfish that had not been seen in 50 years and was presumed extinct due to contamination by local gold mines. The survey's findings underscore the importance of protecting Suriname's rare and delicate mountain forest habitats as the human footprint in the region grows, the scientists said. "Suriname has some of the Amazon's most pristine and intact rainforest, which offers huge potential for scientific research and economic investment," CI's Leeanne Alonso, who led the survey, said in a statement. "Our study will be a vital component in determining how to promote economic development in Suriname while protecting the nation's most valuable natural assets."



A nickname came easily for this newly discovered species, dubbed the big-mouth catfish by scientists who found it in the highlands of eastern Suriname. In addition to its gaping kisser, the big-mouth is unusual for its small size, the researchers said. During their survey of the Surinamese Amazon in 2005, scientists found many species of dwarf catfish, some of which were no more than 2.5 inches (6.3 centimeters) long. This diminutive specimen likely thrives only in Suriname's high-altitude streams, the experts added.


Among the two-dozen new animals recently discovered in Suriname were four frogs belonging to the genus Eleutherodactylus, including this species yet to be named. Though perhaps not as dazzling as their more colorful cousins in the rain forest, frogs of this type are known for their handy adaptations—including muted colors that help camouflage them and eggs that hatch fully formed frogs instead of tadpoles.






This unusual snake is not new to science, but it's an important harbinger of environmental health, according to scientists who found it in Suriname in 2005. The Amazonian snail-eater depends on closed-canopy rain forest for its diet of snails, which the snake can extract from their shells using its slender jaw. The snail-eater, like the more than 450 other animals that the scientists documented in their expedition, is susceptible to disruptions that human activity causes in the rain forest. When reporting their findings in a statement yesterday, the researchers called for improved management of the region to deal with the threats posed by hunting and illegal mining. "Strategies [for future conservation] should focus on protecting freshwater streams and preventing fragmentation of the natural habitat from unchecked or poorly planned development," they said.











A potentially new species of shrimplike crustacean in the genus Epimeria was found near Elephant Island in Antarctica, scientists announced on Sunday. The 1-inch-long (2.5-centimeter-long) creature was among nearly a thousand species collected during the first biological survey of a 3,860-square-mile (10,000-square-kilometer) section of the sea that was once covered by thick polar ice. A 500-billion-ton ice shelf known as Larsen B disintegrated into the Weddell Sea in 2002—seven years after the nearby Larsen A ice shelf broke apart (see an interactive map of Antarctica). Experts believe global warming triggered both events. "The breakup of these ice shelves opened up huge, near pristine portions of the ocean floor, sealed off from above for at least 5,000 years—and possibly up to 12,000 years in the case of Larsen B," Julian Gutt, a marine ecologist at Germany's Alfred Wegener Institute for Polar and Marine Research and chief expedition scientist, said in a media release. "The results of our efforts," Gutt added, "will advance our ability to predict the future of our biosphere in a changing environment."






A male Antarctic sea spider bearing its eggs was found in a region of the sea once covered by a giant ice shelf. The sea spider, or pycnogonid, may prove to be a species new to science. While the breakups of the ice shelves are widely considered dire signs of global warming, the events have provided scientists with a rare opportunity to survey undersea life that had long been hidden by polar ice. "Until now, scientists have glimpsed life under Antarctica's ice shelves only through drill holes," said expedition leader Gutt. "We were in the unique position to sample wherever we wanted in a marine ecosystem considered one of the least disturbed by humankind anywhere on the planet."


Although not documenting a new species, the survey team captured this stunning new image of an Antarctic ice fish surrounded by brittle stars. As an adaptation to the extreme cold of polar waters, the fish has no red blood cells. This makes its blood more fluid, so that the animal can save energy otherwise needed to pump blood through its body.



Fast-growing gelatinous sea squirts are among the species that appear to have recently moved into the Larsen zone. Dense patches of the animals were found in the region that used to be covered by the Larsen B ice shelf. These sea squirts could only have colonized the area, experts say, after the ice shelf collapsed. Examining the region as soon as possible after the event will help establish a baseline for how global warming is affecting polar biodiversity, the survey team says. "This is virgin geography," Gauthier Chapelle, a biologist at the Brussels-based International Polar Foundation, said in the media release."If we don't find out what this area is like now following the collapse of the ice shelf, and what species are there, we won't have any basis to know in 20 years' time what has changed, and how global warming has altered the marine ecosystem."
regards: MAHANEESH CHANDRA

New Monkey Species Found in Remote Amazon

Posted by MAHANEESH | Posted in | Posted on 8:12 AM

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A previously unknown species of uakari monkey was found during recent hunting trips in the Amazon, a New Zealand primatologist has announced.
Jean-Phillipe Boubli of the University of Auckland found the animal after following native Yanomamo Indians on their hunts along the Rio Aracá, a tributary of the Rio Negro in Brazil.

"They told us about this black uakari monkey, which was slightly different to the one we knew from Pico de Neblina National Park, where I'd worked earlier," Boubli said.
"I searched for that monkey for at least five years. The reason I couldn't find it was because the place where they were was sort of unexpected."
Uakaris normally live in flooded river forests, but this one turned up in a mountainous region on the Brazil-Venezuela border, far from its nearest relatives (see map).

"There is another species of primate in that region which is very similar to the uakari," Boubli said.
The two compete ecologically, he added, "so wherever that monkey occurs, you don't expect to find uakaris. That's why I wasn't really looking in those places."
Already Vulnerable
Boubli named the new monkey Cacajao ayresii after Brazilian biologist José Márcio Ayres.
As a senior zoologist for the Wildlife Conservation Society, Ayres—who died in 2003—helped create a protected zone in the heart of the Amazon.
But the newfound Ayres uakari, Boubli said, appears confined to a very small area outside any preserve and is hunted by locals.
"The population is quite small, so they are quite vulnerable. I'm a bit concerned."
Little is known about the creature's habits, but Boubli said it lives in social groups and is likely a seed-eater, based on his observations of other uakaris.
Anthony Rylands, a primatologist at Conservation International, said work such as Boubli's is vital to wildlife protection.
"Many of these tropical forests are being destroyed now," Rylands said. (Read about threats to the world's rain forests.)
"There's a desperate need to save these animals, but we really need to know what animals we're trying to save [and] where they live. Otherwise you can't do anything about it."
Rylands added that today more new primate species are being described in the wake of advances in DNA technology.
"The sophistication of genetic analysis from just about any material—hair, feces—means we're able to get a much more precise view of primate diversity.
"Some of them, especially the nocturnal ones, are really quite cryptic—you can never recognize the differences simply by looking.
"Now … we've suddenly begun to realize that animals we previously considered to be one species are completely different creatures."
Defining the Species
A formal description of C. ayresii has been submitted to the International Journal of Primatology.
Meanwhile, some of Boubli's students will return to Pico de Neblina to study the new monkey's environment and behavior.
"It's very important to define what those monkeys are doing there, how big their range is, because we want to make a case for the Brazilian government to create a reserve," Boubli said.
"Finding a relatively large monkey as a new species these days is pretty cool," he said. "It shows how little we really know about the biodiversity of the Amazon."

In 2003 Boubli described another new species from the region, the bearded saki.
And he believes that new types of spider monkeys, squirrel monkeys, and capuchin monkeys await confirmation.
"If we are still finding monkeys, imagine how many invertebrates and things like that are still out there. It's pretty amazing."

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