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Great Diversity Of Marine Plankton Drive Oceanic PhotosynthesisMarine biologists have demonstrated that there is considerable diversity amongst the smallest microalgae belonging to the group of so-called haptophytes. Scientists have shown that these photosynthetic microorganisms, highly diversified and extremely abundant, are some of the most important producers of oceanic organic matter.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm Chicken-hearted Tyrants: Predatory Dinosaurs As Baby KillersTyrannosaurus rex and other predatory dinosaurs might not have been fearless hunters after all. Using new fossil evidence, researchers in Germany propose that the large carnivores hunted mainly juvenile dinosaurs instead of giant herbivorous adults.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm Fat Hormone Influences Baseline Dopamine Levels And Our Motivation To EatAs we all know from experience, people eat not only because they are hungry, but also because the food just simply tastes too good to pass up. Now, a new study helps to explain how leptin, a hormone produced by fat tissue, influences that motivation to eat.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm ER Physician Tells You How To Avoid A Lightning Strike And What To Do If One OccursAn estimated 200 people die each year in the U.S. after being struck by lightning. An extremely brief but intense hit delivers more than 10 million volts and is fatal in about 30 percent of cases. Recent lightning strikes in Newark resulted in one death and three injuries.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm Why Even Treated Genital Herpes Sores Boost The Risk Of HIV InfectionNew research helps explain why infection with herpes simplex virus-2 (HSV-2), which causes genital herpes, increases the risk for HIV infection even after successful treatment heals the genital skin sores and breaks that often result from HSV-2.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm Gene Shut-down May Offer Early Warning Of Chronic LeukemiaA new study shows that certain genes are turned off early in the development of chronic lymphocytic leukemia (CLL), before clinical signs of the disease appear. The study examined cancer cells from CLL patients and from a new strain of mice that develops a very similar disease. The findings suggest that epigenetic alterations might serve as markers for detecting CLL early and for monitoring progression, and that their reversal might delay or prevent progression.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 6:00 pm Sensitizing Tumor Response To Cancer TherapyResearchers are working to find natural, biologically active compounds that will sensitize cancerous tumors to therapy without damaging normal tissue.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 3:00 pm Common Trigger In Cancer And Normal Stem Cell Reproduction FoundResearchers have discovered, for the first time, a common molecular pathway that is used by both normal stem cells and cancer stem cells when they reproduce themselves.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 3:00 pm Fuel Cell Powered Unmanned Aerial System Achieves Flight Endurance MilestoneResearchers have completed a successful flight test of the fuel cell powered XFC (eXperimental Fuel Cell) unmanned aerial system. During the June 2 flight test, the XFC UAS was airborne for more than six hours.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 3:00 pm Long Debate Ended Over Cause, Demise Of Ice Ages? Research Into Earth's WobbleResearchers have largely put to rest a long debate on the underlying mechanism that has caused periodic ice ages on Earth for the past 2.5 million years -- they are ultimately linked to slight shifts in solar radiation caused by predictable changes in Earth's rotation and axis.Source: ScienceDaily: Latest Science News | 7 Aug 2009 | 3:00 pm The Nation's weather (AP)AP - Wet weather was forecast to diminish across the Eastern U.S. on Friday, while severe weather was expected to pop up over the Central U.S.Source: Yahoo! News: Science News | 7 Aug 2009 | 3:09 am Rarest croc returned to the wildFifty of the world's most endangered crocodiles are released into the wild in a huge step toward saving the species.Source: BBC News | Science & Environment | UK Edition | 7 Aug 2009 | 3:01 am Cannibal theory over early BritonAn ancient bone found in a Devon cave shows signs of dismemberment which could be a sign of rituals and cannibalism.Source: BBC News | Science & Environment | UK Edition | 7 Aug 2009 | 2:37 am Researchers identify cells that say 'scratch me' (AP)AP - Got an itch to scratch? Scientists have pinpointed a key group of cells that sends itch-alerts to the brain. When researchers at Washington University in St. Louis knocked out those cells in mice, it alleviated their itchiness without affecting their ability to sense pain work that opens a possible new target for creating better itch relievers.Source: Yahoo! News: Science News | 6 Aug 2009 | 10:01 pm Cold, Flu or Pneumonia? Answer May Lie in Blood Test (HealthDay)HealthDay - THURSDAY, Aug. 6 (HealthDay News) -- A genomic "signature" in blood appears able to identify people who've been exposed to common upper respiratory viruses, such as the cold or flu, even before symptoms develop.Source: Yahoo! News: Science News | 6 Aug 2009 | 9:48 pm Sperm Cell Insights May Aid Stem Cell Research (HealthDay)HealthDay - THURSDAY, Aug. 6 (HealthDay News) -- Two proteins that play a major role in reverting adult sperm cells back into stem cells have been identified by U.S. researchers.Source: Yahoo! News: Science News | 6 Aug 2009 | 9:48 pm US deficit climbs to 1.3 trillion dollars (AFP)
Source: Yahoo! News: Science News | 6 Aug 2009 | 9:44 pm Nissan's 'Leaf' to challenge Toyota's Prius (AFP)
Source: Yahoo! News: Science News | 6 Aug 2009 | 7:56 pm Scientists find an itchiness cellScientists have pinpointed a specific type of nerve cell in mice which appears to generate the itch sensation.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 5:01 pm Vegetable's juice could help you beet the competition, study saysDrinking beetroot juice boosts stamina and could help people exercise for up to 16% longer, research suggests.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 5:01 pm NASA Steps Closer to Nuclear Power for Moon Base (SPACE.com)
Source: Yahoo! News: Science News | 6 Aug 2009 | 4:45 pm Scientists find nerve cells responsible for itchWASHINGTON (Reuters) - Researchers have found specific nerve cells responsible for itchiness, a discovery that could lead to better treatments for skin conditions.Source: Reuters: Science News | 6 Aug 2009 | 4:23 pm Telescope can find "oodles" of Earths: NASAWASHINGTON (Reuters) - The orbiting Kepler telescope has spotted a Jupiter-sized planet around another star -- a sighting that demonstrates it can see Earth-like planets if they are out there, scientists reported on Thursday.Source: Reuters: Science News | 6 Aug 2009 | 2:22 pm "Big Bang" collider to restart with less energyGENEVA (Reuters) - The giant particle collider built to probe the origins of the universe will restart in November at a lower energy level following its shutdown days after its inauguration last year, CERN said on Thursday.Source: Reuters: Science News | 6 Aug 2009 | 2:13 pm Discovery Really Scratches an Itch (LiveScience.com)LiveScience.com - The urge to scratch a mosquito bite or skin rash can be maddening. Now, scientists have pinpointed a group of neurons that signal it's time to relieve the itch.Source: Yahoo! News: Science News | 6 Aug 2009 | 1:52 pm Titan: A World Much Like Earth (SPACE.com)SPACE.com - Saturn's moon Titan may be worlds away from Earth, but the two bodies have some characteristics in common: Wind, rain, volcanoes, tectonics and other Earth-like processes all sculpt features on Titan, but act in an environment more frigid than Antarctica.Source: Yahoo! News: Science News | 6 Aug 2009 | 1:46 pm Kepler Shows Exoplanet Is Unlike Anything in Our Solar System
The Kepler Space Telescope, which launched earlier this year to find Earth-like planets elsewhere in our galaxy, showed it’s open for business with NASA’s announcement that an exoplanet we thought we knew is like nothing we’ve seen before. Peering at a large planet orbiting very close to its star, HAT-P-7b, the telescope delivered what one scientist called “exquisite” data, proving that it’s ready to start looking for Earth-sized planets in the habitable zones around stars. Analyzing just 10 days of data, the scientists even turned up a major surprise: HAT-P-7b isn’t like Jupiter at all. It has a “dark” side and its atmosphere could be made of relatively exotic chemicals like titanium oxide. “This planet is not like anything in Earth’s solar system,” said Sara Seager, an exoplanetary scientist at MIT. The hottest spot on Hat-P-7b could be more than 1,300 degrees Fahrenheit warmer than the coldest spot. There is no comparable planet around our star. Kepler’s first findings, some of which were published in the journal Science, augur a new level of exoplanetary research, Seager said. “This exquisite data is just the tip of the iceberg,” she said. “We’re going to see a new world of exoplanet exploration where discoveries will come much more rapidly than they’ve come in the last 10 years.” But while we’ll be learning more about planets in the universe every month, Kepler’s ultimate mission — finding Earth-like planets in the habitable zone — is still going to take years.
The habitable zone is the term astronomers use to denote the distance from a star where orbiting planets wouldn’t get fried or frozen. In those locations, liquid water could exist — and that’s something that is necessary for life as we know it. In our solar system, Venus, Earth, and Mars lie within the zone. The more planets that Kepler finds in its survey of 100,000 stars, the more likely that Earth-like planets exist in large numbers throughout the universe. And the more Earths out there, the better our chances get of finding life outside our solar system. The announcement that Kepler is working as designed is great news for the exoplanetary research community, which had been eagerly awaiting the first data from the instrument. “It appears Kepler is working at its design precision — the noise level of just 40 parts per million per data point is amazing!” Matthew Muterspaugh, an exoplanet researcher at Tennessee State University, wrote in an email to Wired.com. Kepler’s mission is primarily statistical. It will tell us how many solar systems like ours likely exist in the universe, but the stars in its field of vision are too far away to characterize in much detail. Kepler will be able to tell us that the planet is in the right place, but not whether it’s suitable for or home to life. “[Kepler] will be able to say it’s a rocky planet like Venus or Earth, but won’t be able to say whether it’s more like Venus or Earth,” Muterspaugh said. So, while Kepler will help sort out how likely life is around the universe, it won’t actually find any definitive signs of it. The stars that it’s looking at are just too far away. “The downside to the Kepler technique is that the stars tend to be very far away and faint,” said Muterspaugh. “This set of stars will not be well optimized for the follow up observations.” The ultimate quest to find other planets that support life will require a series of other missions and telescopes, which focus on planets much closer to home. First, we’ll have to find out which local stars have rocky planets. NASA’s first potential mission with that capability is the SIM Lite Astrometric Observatory. It will be able to find Earth-sized planets around 60 stars in our neighborhood. Once these planets are identified by SIM or other missions like Gaia and CoRoT, NASA will be able to peer at them with the powerful James Webb Space Telescope or a dedicated planet-hunting telescope like the agency’s proposed Terrestrial Planet Finder missions. For planets larger than Earth, the James Webb telescope will be able to characterize them effectively, but for the true Earths, we’ll need the more powerful instrumentation of the TPF. It will be a long road from finding the first Earth-like planet with Kepler to knowing how habitable any extrasolar planet is, but if all goes well, scientists think we could have answers by 2020. “The timeline is set for in 2020 having that image of our brother world out there,” Muterspaugh said. “I think that this is a fantastic thing for our generation to do, answering a question that’s thousands of years old: are we alone?” See Also:
Images: NASA. 1. Kepler is prepared for launch. It was kept covered. 2. An artist’s rendering of Kepler on orbit. WiSci 2.0: Alexis Madrigal’s Twitter, Google Reader feed, and green tech history research site; Wired Science on Twitter and Facebook.
Source: Wired: Wired Science | 6 Aug 2009 | 1:44 pm BLOG: El Nino Suppresses HurricanesEl Nino tends to cut off the tops of tropical storms before they develop into hurricanes.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 12:45 pm Rooks Prove They're as Clever as Fabled CrowA thirsty crow raises water level with stones -- in the fable and in new research.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 12:45 pm Stop the ItchMice without itch-specific neurons (left) didn't scratch themselves after being exposed to an itchy agent. But their normal littermates (right) did.Source: Livescience.com | 6 Aug 2009 | 12:39 pm Discovery Really Scratches an ItchScientists find neurons in mice exclusively linked with itching.Source: Livescience.com | 6 Aug 2009 | 12:17 pm Titan: A World Much Like EarthWeather and surface processes on Titan are Earth-like but in much colder environment.Source: Livescience.com | 6 Aug 2009 | 12:13 pm Self-Assembling DNA Makes Super 3-D Nano Machines
William Shih has a bridge to sell, but you’ll need a powerful microscope to see it: It’s built entirely from DNA strands, handrails and all. The bridge is just one of a whole range of intricate three-dimensional shapes Shih has crafted using DNA’s unique capacity for precise self-assembly. In a study Thursday in Science, his team has shown they can even control the precise curvature of these tiny structures, which is key to making wheels, hooks and gears. Unlike building nano portraits of Obama, This isn’t just an artistic exercise. Scientists in the burgeoning field of structural DNA nanotechnology are exploring DNA’s potential as raw material for next-generation circuits, sensors and biomedical devices. Advocates say it could become the new go-to material for engineers, scientists and clinicians. “DNA is the world’s greatest architectural material, in my opinion,” said NYU chemist Ned Seeman, the field’s founder and lonely apostle. In addition to its well-known sequence specificity — A only binds T, G only binds C — DNA’s structural properties have been intensely studied for over half a century, and one can predict the atomic-level structure of virtually any DNA construct with remarkable accuracy. Since the 1980s, Seeman has been quietly designing DNA strands that self-assemble into interlocking tiles, three-dimensional polyhedrons and even nanomachines that automatically ‘walk’ along other DNA strands. In 2006, the technology finally entered the scientific limelight, heralded by a Nature cover festooned with cheerful smiley faces, each composed of a long, folded strand of DNA meticulously wrangled into shape with tiny DNA “staples,” a technique that its inventor, CalTech computer scientist Paul Rothemund, termed “DNA origami.” “There are at least a dozen groups focusing on things [Seeman] invented, and a larger number working on this at the periphery,” said Shih, who is at the Dana-Farber Cancer Institute.
In May, scientists at Copenhagen’s Center for DNA Nanotechnology described a DNA-based box with a lid that stays locked until exposed to a DNA-based key, which prompts the lid to pop open and potentially release a drug. A team led by McGill University chemist Hanadi Sleiman is also building DNA cages and nanotubes for delivering treatments. “This might be the kind of thing that comes into cells and only opens up when it’s triggered by a gene that’s overexpressed in very specific cells,” Sleiman said. But perhaps the field’s greatest promise is in using DNA as a foundation for more sophisticated devices. Because complementary DNA sequences recognize each other, short DNA strands can act as “address labels” to direct cargos to exact locations on a larger DNA origami scaffold. Tagged proteins, chemical compounds and even nanoscale electronic components are able to find and claim their proper positions with atomic-scale precision to form complex molecular machines that essentially build themselves. In the latest study, Shih’s team created curves in DNA structures by adding or deleting DNA base pairs to create tension that causes the strands to bend. “DNA structures are the ’smart’ materials which we use to assemble ‘dumb’ materials, but these dumb materials can have other interesting properties,” said Duke University chemist/computer scientist Thom LaBean, who is currently working on tiny DNA-templated wires and single-electron transistors that could convert DNA scaffolds into nanoscale circuitboards. LaBean is also working on ‘biocomputers’ made from DNA, RNA and protein that respond to biological signals. For example, A DNA-based sensor that recognizes RNA messages produced because of cancer or viral infection could trigger the release of RNA or DNA strands with therapeutic properties. Such applications should benefit considerably from the new three dimensional opportunities. “Distances can be shorter, and you can get a lot more stuff into 3D than 2D,” Seeman said. “Ultimately, self-assembly in 3D will enable things that self-assembly in 2D won’t.” One possibility, being developed by Sleiman, is a DNA solar cell that incorporates metal atoms and other chemical components to mimic the efficient mechanisms bacteria use to derive energy from the sun. “Nature just positions all these different functional elements exactly right in three-dimensional space in order to create this bacterial photosynthesis machine,” she said. “And no self-assembling system can rival what DNA can do in terms of positioning.” There are of course obstacles, such as finding cheaper ways to produce bulk quantities of DNA, optimizing the design and construction process, and demonstrating safety in humans. Even more fundamental are the matters of convincing a skeptical scientific community and acquiring funding. Recruiting people who can wrap their heads around such highly interdisciplinary work, which brings together elements of biology, physics, chemistry, computer science and materials, is also a challenge. On the other hand, the inherent sexiness of DNA nanotechnology makes it an easy sell for prestigious journals like Science and Nature, and most practitioners seem optimistic that the scientific community will ultimately recognize the power of structural DNA nanotech. “I think the general idea of being able to control the fine structure of matter… could potentially affect a lot of areas of technological interest,” Shih said. “We need some more killer applications, and then we’ll punch through the threshold, and there will be more general appreciation for this field.” Image: Science/AAAS
Source: Wired: Wired Science | 6 Aug 2009 | 12:00 pm BLOG: Exploding Star Could Spell TroubleIf WR 104 explodes as a gamma-ray burst, it may do serious damage to our planet.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 12:00 pm New Image Reveals Nebula's Double Star HeartA new look at a distant nebula has revealed two stars in its heart.Source: Livescience.com | 6 Aug 2009 | 11:38 am Lightning Detected on MarsScientists make first detection of lightning on Mars during a dust storm.Source: Livescience.com | 6 Aug 2009 | 11:37 am US glaciers are melting at the fastest rate in recorded historyUS geological survey commissioned by Obama administration indicates a sharp rise in the melt rate of key American glaciers over the last 10-15 years Climate change is melting America's glaciers at the fastest rate in recorded history, exposing the country to higher risks of drought and rising sea levels, a US government study of glaciers said today. The long-running study of three "benchmark" glaciers in Alaska and Washington state by the US geological survey (USGS) indicated a sharp rise in the melt rate over the last 10 or 15 years. Scientists see the three - Wolverine and Gulkana in Alaska and South Cascade in Washington - as representative of thousands of other glaciers in North America. "The observations show that the melt rate has definitely increased over the past 10 or 15 years," said Ed Josberger, a USGS scientist. "This certainly is a very strong indicator that climate change is occurring and its effects on glaciers are virtually worldwide." The survey also found that all three glaciers had begun melting at the same higher rate - although they are in different climate regimes and some 1,500 miles apart. For South Cascade, the average surface loss rate grew to 1.75 to 2m a year from about 1m a year. USGS researchers have been measuring the three glaciers for more than 50 years, drawing on photographs and a network of stakes driven into the glaciers to gauge the accumulation of snow during winter, and the resulting melt each spring. It is the oldest such record of glacier activity. In a sign of the Obama administration's focus on climate change, this year's survey was promoted by the interior secretary, Ken Salazar, who called it an important contribution to dealing with climate change. "This information is helpful in tackling the effects of climate change and it is exactly the kind of science we need to invest in to measure and mitigate the dangers impacts of climate change," he said. Shrinking glaciers have led to a reduction in spring run-off which is intensifying the effects of drought in California and other states, especially later in the summer when other water sources dry up. Glacier loss has also contributed to rising sea levels, which has put low-lying coastal areas - such as New Orleans - at greater risk of storm surges. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 6 Aug 2009 | 11:09 am NOAA cuts hurricane forecast, cites El Nino (Reuters)Reuters - The U.S. government climate agency cut its 2009 Atlantic hurricane season forecast on Thursday, predicting between seven and 11 tropical storms, with three to six becoming hurricanes.Source: Yahoo! News: Science News | 6 Aug 2009 | 10:58 am Clever rooks repeat ancient fableFootage of clever rooks reveal that one of Aesop's fables may be based on fact, scientists report.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 10:39 am Roman Emperor Vespasian's Villa FoundThe summer home of the emperor who built the Colosseum has been discovered.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 10:30 am VIDEO: Blind Drivers Hit The RoadBlind drivers test a new vehicle that allows them to cruise without seeing.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 10:15 am Spitzer Spots Swirling Stars at the Center of the Galaxy
This striking infrared image, captured by NASA’s Spitzer Space Telescope, shows the center of our Milky Way Galaxy crowded with stars. Dust usually obscures our view into the center of the galaxy 26,000 light years away, but the Spitzer’s keen infrared eyes can see through dust. This photograph is actually a composite of many smaller snapshots taken by the infrared camera. Older, cooler stars appear blue while younger, hotter ones cluster in clouds of reddish dust. See Also:
Image: Susan Stolovy et al/NASA, JPL-Caltech.
Source: Wired: Wired Science | 6 Aug 2009 | 10:09 am Bird's Tool Use Called 'Amazing'Crows' fabled ingenuity shines in intelligence tests.Source: Livescience.com | 6 Aug 2009 | 10:06 am Clever Crows Prove Aesop’s Fable Is More Than Fiction
Aesop’s fables are full of talking frogs and mice who wear clothes, but it turns out at least one of the classic tales is scientifically accurate. Researchers presented four crows with a challenge from Aesop’s fable “The Crow and the Pitcher”: a container of water not quite full enough for the birds to reach with their beaks. Just like Aesop’s crow, all four birds figured out how to raise the water level by dropping stones into the glass. The crows also selectively chose large pebbles over small ones, and quickly realized that dropping rocks into a container of sawdust didn’t have the same effect.
The researchers took four adult rooks, a type of intelligent crow, and tempted them with a tasty worm floating on top of a glass of water, just out of reach. Then they placed a pile of small rocks next to the crows. After they assessed the height of the water from the top and sides of the glass, the crows dropped stones into the glass until the water level rose enough for them to grab their prize. Once they’d caught the worm, the birds didn’t keep putting stones in the glass, and they didn’t try to grab the worm until they’d dropped in a certain number of stones. “This number was strongly correlated to the number of stones needed to raise the water level to the correct height,” the researchers wrote, “suggesting that, having assessed the starting level of the water, rooks translated this into an estimate of the number of stones needed.”
Before this experiment, the birds had never been exposed to a glass with water in it, and they’d never used stones as tools. According to the researchers, the only other animal known to perform this kind of task is the orangutan, which has been recorded spitting into a tube to bring a peanut into reach. “Corvids are remarkably intelligent, and in many ways rival the great apes in their physical intelligence and ability to solve problems,” said biologist Christopher Bird of the University of Cambridge in a press release. “This is remarkable considering their brain is so different to the great apes’.” The antics of the four birds — Cook, Fry, Connelly and Monroe — can be seen in the videos below. Cook and Fry snagged the floating worm after just one try, while Connelly and Monroe succeeded after two attempts. Unfortunately, Fry had a bad reaction to one of the worms and gave up in the middle of the experiment. Connelly captures the worm: Monroe picks out large stones instead of small stones: Cook has realized that sawdust doesn’t work as well as water: See Also:
Image 1: Flickr/jpmckenna. Image 2: Illustration by Milo Winter from The Aesop for Children/Project Gutenberg etext 19994. Videos: Christopher Bird and Nathan Emery/Current Biology.
Source: Wired: Wired Science | 6 Aug 2009 | 10:02 am Masters of disguiseWhether to avoid predators, lure prey or attract pollinators, natural selection has crafted some remarkable lookalikes
Source: Science news, comment and analysis | guardian.co.uk | 6 Aug 2009 | 9:46 am BLOG: Late Night Polar Bear EncounterA surprise encounter with a polar bear charms the crew of a ship in the Arctic.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 9:35 am Venomous snake proves that two heads are better than oneThe yellow-lipped sea krait has evolved an ingenious way to scare off predators while its head is otherwise engaged Having a head full of venomous fangs is great for scaring off predators. Better still, two heads. Sea snakes are fearsome predators in their own right, feeding on small fish that they find lurking around coral reefs. But when they poke their heads into crevices to look for their next meal, they let their guard down and run the risk of getting eaten themselves, by larger fish such as sharks. The yellow-lipped sea krait, which is a native of the Pacific and Indian Oceans, has evolved a clever way to ward off predators while foraging. The coloration of its tail end is strikingly similar to its head, and when the snake sticks its real head into nooks and crannies to look for food, the tail moves around like a head to enhance the illusion. Zoologist Arne Redsted Rasmussen discovered the snake's cunning defence strategy while diving in Indonesia. Rasmussen was puzzled when he saw a snake probing coral with what he thought was its tail. When the snake swam away, "tail" first, he realised it was using its coloration and behaviour to fool him and other potential predators. Rasmussen and his colleague Johan Elmberg examined 98 sea krait specimens from museums in Paris, Berlin and Copenhagen, and found that all of them had the same distinctive head and tail markings. Rasmussen also noticed a similar adaptation in another species, the thick-tailed sea snake. Their research is reported in the journal Marine Ecology. "The value of such an adaptation is twofold," the researchers write. "It may increase the chances of surviving predator attack by exposing a less 'vital' body part, but more importantly it may deter attack in the first place if attackers perceive the tail as the venomous snake's head." However, there are limits to how head-like the tail can be made to look. Rasmussen and Elmberg note that the tail's adaptation involves a trade-off between looking like a head and being good for swimming. The tail has to be slightly flattened to allow it to act like a paddle – which reduces its resemblance to the head. But the head-like way the tail twists about when the snake is foraging in a crack might make up for this. Other snakes are known to exhibit "false head" behaviour, but only when they become aware of an imminent threat. This is the first time scientists have come across a snake that uses body markings and behaviour to ward off predators pre-emptively while it forages. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 6 Aug 2009 | 9:20 am China probe to launch in OctoberChina's first unmanned Mars probe is being readied for a launch later this year, state media reports.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 8:54 am BLOG: Shark Tags Go the DistanceSince the 1960s, around 200,000 sharks have been tagged, but data holes remain.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 8:53 am Shark Repellent Disk Emits Electric VoltsA disk clamped onto fishing gear protects sharks by creating a mild electric current.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 8:15 am Robot Chefs Run a RestaurantThese chefs will get your order right every time.Source: Livescience.com | 6 Aug 2009 | 8:08 am Why Americans Don't Act on Climate ChangeThe way people think and feel about climate change may dictate how green they'll go.Source: Livescience.com | 6 Aug 2009 | 8:00 am No Evidence That Therapy Can Turn Gays StraightPsychologists have taken a controversial stance on the issue of sexual orientation.Source: Livescience.com | 6 Aug 2009 | 7:41 am South Africa reaching to space to boost economyCAPE TOWN (Reuters) - South Africa aims to become a regional center for space technology, investing in satellite and telescope projects to support its ailing economy, the science and technology minister said on Thursday.Source: Reuters: Science News | 6 Aug 2009 | 7:33 am Swine flu vaccine 'by September'The first swine flu vaccines are likely to be licensed for use in the general population in September, the World Health Organization has announced.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 7:12 am Oldest Known Paralyzed Human DiscoveredThe oldest known paralyzed man survived despite his condition.Source: Discovery News Top Stories : Discovery Channel | 6 Aug 2009 | 6:30 am Hoover marvelBridge arch reaches for the skies over famous US damSource: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 6:18 am How to Get Cancer: Move to the United StatesThe risk of cancer for Hispanics living in Florida is 40 percent higher than for those who live in their native countries.Source: Livescience.com | 6 Aug 2009 | 6:12 am Trial and error?Concern that swine flu jabs could be a shot in the darkSource: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 6:05 am Indian vulture births are hailedConservationists say they are delighted that one of the world's most endangered birds have twice been successfully bred in India.Source: BBC News | Science & Environment | UK Edition | 6 Aug 2009 | 5:19 am Boost for endangered vultures after captive breeding successTwo slender-billed vultures born in RSPB breeding programme in India as wild population heads towards extinction One of the world's most threatened birds has been successfully bred in captivity for the first time, conservationists said today. The slender-billed vulture, which is even more threatened than the tiger in India, is one of several Asian species of the carrion-eating bird which has seen dramatic declines in numbers in recent years and are now critically endangered. There are just 1,000 slender-billed vultures left in the wild, according to the RSPB. Conservationists say successfully breeding one of the birds in captivity is a "huge boost" to efforts to prevent it becoming extinct in the wild. The slender-billed vulture and another species, the long-billed vulture, have together suffered declines of almost 97% since 1992. The population of a third of critically endangered species, the oriental white-backed vulture, is halving each year and is heading towards extinction even more quickly than the dodo. The vultures have been hit by the use of the veterinarian drug Diclofenac which gives them kidney failure when they eat the carcasses of livestock that have died within a few days of being treated with the medication. A captive breeding scheme in India, run by a coalition of conservation groups including the RSPB and the Zoological Society of London, has seen the successful hatching and fledging of two slender-billed vultures for the first time this year. Last year, the dedicated breeding centres managed to rear Oriental white-backed vultures for the first time, and repeated their success this year with three chicks. "It is clear we are refining our expertise, but with extinction in the wild likely in the next 10 years, we do not have a moment to waste," said Chris Bowden, who is in charge of the RSPB's Asian vulture programme. "The more vultures that we can bring into captivity means a better chance of survival for these rapidly-declining species. Birds can only be saved from extinction through banning the retail sale of Diclofenac, promotion of the safe alternative, Meloxicam, and the capture of more birds for the breeding programme." The RSPB said veterinary formulations of Diclofenac had been banned in India since 2006 and efforts to take it out of use there and in Nepal were taking effect. But more steps were needed to prevent versions of the medication which are being illegally given to livestock, and introduce the safe alternative Meloxicam. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 6 Aug 2009 | 3:58 am
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“The results of these experiments provide the first empirical evidence that a species of corvid is capable of the remarkable problem-solving ability described more than two thousand years ago by Aesop,” wrote the researchers in the paper published Thursday in Current Biology. “What was once thought to be a fictional account of the solution by a bird appears to have been based on a cognitive reality.”