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Why Israeli rodents are more cautious than Jordanian onesRodent, reptile and ant lion species behave differently on either side of the Israel-Jordan border. Researchers found that Israeli gerbils are more cautious than their Jordanian friends, and the funnel-digging ant lion population in Israel is unmistakably larger than in Jordan.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm On your last nerve: Researchers advance understanding of stem cellsResearchers have identified a gene that tells embryonic stem cells in the brain when to stop producing nerve cells called neurons. The research is a significant advance in understanding the development of the nervous system, which is essential to addressing conditions such as Parkinson's disease, Alzheimer's disease and other neurological disorders.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm New cause of osteoporosis: Mutation in a miroRNAMany biological processes are controlled by small molecules known as microRNAs. Researchers have now identified a previously unknown microRNA (miR-2861) as crucial to bone maintenance in mice and humans; significantly, expression of functional miR-2861 was absent in two related adolescents with primary osteoporosis.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm Frog legs trade may facilitate spread of pathogensMost countries throughout the world participate in the $40-million-per-year culinary trade of frog legs in some way, with 75 percent of frog legs consumed in France, Belgium and the United States. Scientists have found that this trade is a potential carrier of pathogens deadly to amphibians.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm Bacterially produced antifungal on skin of amphibians may protect against lethal fungusA new study suggests that naturally occurring bacteria on the skin of salamanders could help protect other amphibians, including some species of endangered frogs, from a lethal skin disease.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm Ancestry attracts, but love is blindPeople preferentially marry those with similar ancestry, but their decisions are not necessarily based on hair, eye or skin color. Research shows that Mexicans mate according to proportions of Native-American to European ancestry, while Puerto Ricans are more likely to settle down with someone carrying a similar mix of African and European genes.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 6:00 pm Spinal cord injuries: Experimental drug may restore function of nervesResearchers have shown how an experimental drug might restore the function of nerves damaged in spinal cord injuries by preventing short circuits caused when tiny "potassium channels" in the fibers are exposed.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 3:00 pm Braking news: Particles from car brakes harm lung cellsReal-life particles released by car brake pads can harm lung cells in vitro. Researchers found that heavy braking, as in an emergency stop, caused the most damage, but normal breaking and even close proximity to a disengaged brake resulted in potentially dangerous cellular stress.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 3:00 pm Let them eat snail: Nutritional giant snails could address malnutritionA nutritionist in Nigeria says that malnutrition and iron deficiency in schoolchildren could be reduced in her country by baking up snail pie. She explains snail is not only cheaper and more readily available than beef but contains more protein.Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 3:00 pm Solving the 50-year-old puzzle of thalidomideResurgence of thalidomide use in Africa and South America raises the urgent need to isolate the negative side effects by identifying the drug's "common mechanism."Source: ScienceDaily: Latest Science News | 20 Nov 2009 | 3:00 pm 200 in UK tourist region rescued from floodwaters (AP)
Source: Yahoo! News: Science News | 20 Nov 2009 | 3:13 am The nation's weather (AP)AP - New England was expected to see another dreary day, while the Pacific Northwest remains under wintry conditions on Friday.Source: Yahoo! News: Science News | 20 Nov 2009 | 3:02 am Biologists save fish after landslide (AP)AP - A gigantic landslide that buried a highway, uprooted homes and rerouted a river in Washington state's Cascade Range left hundreds of smaller victims: fish.Source: Yahoo! News: Science News | 20 Nov 2009 | 2:41 am Shun beef to stop climate change, says India (AFP)
Source: Yahoo! News: Science News | 20 Nov 2009 | 2:39 am Military experiment seeks to predict PTSD (AP)
Source: Yahoo! News: Science News | 20 Nov 2009 | 1:17 am Astronauts get extra moving time at space station (AP)
Source: Yahoo! News: Science News | 20 Nov 2009 | 1:16 am Bardot urges end to animal sacrifice in Nepal (AFP)
Source: Yahoo! News: Science News | 19 Nov 2009 | 10:57 pm Teams Compete to Build a Better Astronaut Glove (SPACE.com)SPACE.com - NASA offered a total of $400,000 to inventors who can make stronger and more dexterous spacesuit gloves Thursday in the second Astronaut Glove Challenge.Source: Yahoo! News: Science News | 19 Nov 2009 | 8:16 pm The Digital Divide: Why Grandma Should Get Online (LiveScience.com)LiveScience.com - Grandma doesn't spend much time online - but she would be better off if she did, researchers agree.Source: Yahoo! News: Science News | 19 Nov 2009 | 8:01 pm When Good Rockets Go Bad<< previous image | next image >>
In the grand scheme of human space programs in Russia and the United States, catastrophic failures are relatively rare. But they are often quite spectacular and make a big impression on the public and on the funding for space exploration. The explosions in the videos we’ve assembled here were very costly, some in terms of life, some in terms of lost equipment and all in terms of progress of the space programs. Vanguard TV3 Fuel Tanks ExplodeDec. 6, 1957: The United States’ first attempt to launch a satellite into orbit was also its first failure. Two seconds after leaving the launch pad at Cape Canaveral, this rocket lost thrust and sank back down, rupturing and exploding its fuel tanks. It had reached a height of about 4 feet. Though the rocket was destroyed, the Vanguard satellite it was carrying was thrown clear, its transmitters still signaling. The satellite is now on display at the Smithsonian’s Air and Space Museum. Video: NASA
Source: Wired: Wired Science | 19 Nov 2009 | 6:08 pm Malaria Gaining Resistance to Best Available Treatment
WASHINGTON — Malaria that is resistant to the best available drug is more widespread in Southeast Asia than previously reported, new research shows. The worrisome finding poses a risk that travelers could carry this strain of the malaria parasite to other parts of the globe and unwittingly spread it, scientists reported November 19 at a meeting of the American Society of Tropical Medicine and Hygiene.
“Things are changing. There’s no doubt the signs are concerning,” said Robert Newman, director of the Global Malaria Programme at the World Health Organization in Geneva. But he added that these signals are early and need further verification. Patients in these areas take longer on average to overcome a malaria infection when given a standard combination of artemisinin and another antimalarial. This lag results from slower clearance of the malaria parasites from the blood, said WHO’s Pascal Ringwald, a medical officer who presented the update.
Patients who remain ill for longer stretches despite treatment need extra medication to recover from malaria and are also more likely to have severe or fatal cases, Ringwald said. Malaria is caused by a single-celled parasite that infects the blood. Symptoms include fever, headache, chills, anemia and a swollen spleen. Of the more than 350 million people who come down with malaria worldwide each year, up to 1 million die. Mosquitoes spread the parasite from person to person. Malaria has a history of becoming resistant to drugs, and artemisinin now risks becoming the most recent addition to that list. The new reports are disheartening to doctors because artemisinin normally packs a considerable wallop. Although artemisinin is a short-acting drug that gets cleared from the body in a few hours, it makes the most of its time — driving down parasite levels dramatically. Using artemisinin alone invites resistance. So the standard therapy teams it with one of the longer-acting drugs, which perform mop-up duty on the remaining parasites, said Christopher King, a physician and epidemiologist at Case Western Reserve University in Cleveland. The new flashes of resistance may have arisen because combination treatment isn’t always available. And since artemisinin can be bought over the counter in many parts of Asia, people seeking relief don’t always follow the WHO guidelines of pairing artemisinin with another drug, King said. Also, taking artemisinin for a fever that isn’t caused by malaria can allow resistant strains of the parasite to take hold, Newman said. In the past, malaria’s resistance to other drugs has been linked to specific genetic changes in the parasite. The precise mechanism underlying resistance to artemisinin is still unsolved, King said. Artemisinin is derived from extracts of the sweet wormwood bush. The bush’s leaves have been used as a folk remedy against fevers for roughly 2,000 years in Asia but fell out of use in the 20th century with the introduction of modern antimalarial drugs such as chloroquine. During the Vietnam War, North Vietnamese leader Ho Chi Minh appealed to China for traditional remedies for soldiers who had malaria. Tea made from sweet wormwood leaves worked and ultimately became the basis for artemisinin drugs. It’s not clear whether parasites in Southeast Asia are the first to become resistant because they have had a long history with artemisinin, or if other factors are involved, Newman said. Image: Malaria from Plasmodium falciparum. Flickr/Got_Jenna See Also:
Source: Wired: Wired Science | 19 Nov 2009 | 5:44 pm Asthma Combo Seems Less Influenced by Genes (HealthDay)HealthDay - THURSDAY, Nov. 19 (HealthDay News) -- People's genetic makeup has been shown to affect how they respond to asthma medications, but a new study finds that many people respond well to a particular combination treatment regardless of their genes.Source: Yahoo! News: Science News | 19 Nov 2009 | 5:25 pm Letters: Girls can aspire to be high-flyersAs a group representing professional women working in science, technology, engineering, mathematics, social sciences, medicine and health in a leading UK university, we found your report on the lecture by Jill Berry, president of the Girls' Schools Association (Girls 'need to be realistic' about careers, 14 November) utterly depressing. We are saddened that arguments for equal opportunities have to be made over and over again. Berry asserts that a woman's aspiration for a high-flying career can "all work fine, until their children are ill", ignoring the fact that parents, male and female, often share this responsibility. We are successful scientists, researchers and educators. Many of us daily attest to the fact that having children, ill or otherwise, does not wreck a career. Those of us who are mothers also acknowledge men and women who combine caring responsibilities with paid employment. Women scientists are not "superwomen", as Jill Berry would lead her pupils to believe, just ordinary women who get immense satisfaction from doing a job they enjoy. Some combine this with raising a family or caring for others. The reiteration of tired arguments about a woman having to balance the desire for a family against career aspirations is alarming. Are we to return to an era when careers advisers had separate lists of jobs suitable for girls? Half the UK's talent resides in individuals that carry two X chromosomes. To discourage girls and women from developing their potential and achieving financial independence not only denies them fundamental equality but damages the economy and society. We must get real about tackling inequality of opportunity. Professor Lindy Holden-Dye, Professor Catherine Pope, Professor Dame Wendy Hall, Dr Pamela Jackson, Professor Andrea Russell, Professor Jane Hart, Professor Geraldine Clough, Dr Kanchana Ruwanpura, Dr Vesna Perisic, Professor Mark Spearing, and 11 others Women in Science and Technology group, University of Southampton Professor Lindy Holden-Dye Professor Catherine Pope Professor Dame Wendy Hall DBE FREng FRS Dr Pamela Jackson Professor Andrea Russell Professor Jane K Hart Professor Geraldine Clough Dr Kanchana N Ruwanpura Dr Vesna Perisic Dr Brita Nucinkis Professor Mark Spearing Dr Su White Professor AC Tropper Professor Jeremy Kilburn Dr Malgosia Kaczmarek Diana Caicedo Clare Hooper Asa Asadollahbaik Rocio Aldeco-Perez Kamaljit Kerridge-Poonia Sunny Takhar For an on behalf of the Women in Science and Technology (WiSET) group at the University of Southampton 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 | 19 Nov 2009 | 5:05 pm Czech zoo lions kill rare tigerTwo lions at a zoo have killed a rare white tigress.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 3:54 pm Spacewalk for shuttle astronautsTwo astronauts from the space shuttle Atlantis have embarked on the first spacewalk of their mission.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 3:45 pm First test for record solar planeThe prototype of a solar-powered plane destined for a record round-the-world journey makes its first trip across a runway.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 3:45 pm Thinspiration: Do Web Sites Encourage Anorexia?New Web sites promoting anorexia have caused public health concerns.Source: Livescience.com | 19 Nov 2009 | 3:36 pm Sushi Often Not What You ThinkEndangered bluefin tuna ends up in sushi without being labeled.Source: Livescience.com | 19 Nov 2009 | 3:35 pm Google Bets Big on Internet With ChromeGoogle's new operating system promises to bring cloud computing to the masses.Source: Livescience.com | 19 Nov 2009 | 3:17 pm Paralyzing Light BeamTiny nematodes are paralyzed by ultraviolet light in a new study. They stay that way until regular light is turned on.Source: Livescience.com | 19 Nov 2009 | 2:59 pm New fossils reveal a world full of crocodilesWASHINGTON (Reuters) - New fossils unearthed in what is now the Sahara desert reveal a once-swampy worldSource: Reuters: Science News | 19 Nov 2009 | 2:21 pm Dung Fungus Provides New Evidence in Mammoth Extinction
The latest evidence in the disappearance of the mammoths, and nine other North American species weighing over a ton, comes from fossilized dung fungus. But despite their lowly origin, if the new findings hold, they point away from human causes and could rule out an asteroid impact altogether. By studying the abundance over time of a fungus that lived only in the dung of these animals, scientists have revealed that the animals began to decline in numbers earlier than previously believed. Much of the uncertainty surrounding the extinction of the North American megafauna, which includes mastodons, saber-tooth tigers and giant ground sloths, is due to a scarcity of evidence and difficulty pinning down the timing of events. Several major events occurred around the same time the animals disappeared: Major environmental upheaval associated with the end of the Ice Age; an asteroid explosion over North America; and the arrival of man. Because the youngest megafauna fossils found are around 13,300 to 12,900 years old, the asteroid which is hypothesized to have impacted Earth’s atmosphere around 12,900 years ago seemed like a good bet for the cause of the extinctions. But, the short-lived Clovis culture inhabited North America around the same time. Now the new study, led by scientists at the University of Wisconsin-Madison and published Thursday in Science, fills some holes with a different type of data. By studying the abundance over time of a particular fungus that produces spores in the dung of big herbivores, a team of scientists determined that the animals’ major decline occurred much earlier. “Megafaunal populations collapsed from 14,800 to 13,700 years ago, well before the final extinctions,” the authors wrote.
This effectively exculpates the asteroid impact, and makes the case for human causes thinner. “If people were responsible for the decline, they must have been pre-Clovis settlers,” Christopher Johnson, who studies the extinction of the Australian megafauna at James Cook University in Queensland, wrote in a commentary in Science. Though the Clovis people were long believed to be the first North American settlers, new evidence of earlier settlers that arrived around the time that the fungus shows the decline beginning has begun popping up. The idea of a pre-Clovis peopling is still hotly debated, but even if it didn’t exist or wasn’t robust enough to have a major effect on the animals, the Clovis people could have dealt the final blow or contributed to the ultimate demise of the megafauna. The scientists also studied pollen from the time period and discovered that as the large herbivores declined, a new set of broad-leaved trees began flourishing. This woodland could have arisen because the animals that fed on those plants and kept them in check weren’t around anymore. And because these major changes in the environment occurred after the animals were in decline, this is a strike against the idea that climate caused the changes which then caused the extinctions. The new research adds much needed information to a spotty fossil record and scattered clues. But the question of whether or not humans caused the demise of North America’s giant beasts has always provoked strong feelings and intense debate, and this latest evidence is likely to stir things up more than it helps settle them. Image: Mastodons, giant ground sloths and camels./Barry Roal Carlsen, University of Wisconsin-Madison Citation: “Pleistocene Megafaunal Collapse, Novel Plant Communities, and Enhanced Fire Regimes in North America,” by J.L. Gill; J.W. Williams; K.B. Lininger at University of Wisconsin-Madison, WI; S.T. Jackson at University of Wyoming, Laramie, WY; G.S. Robinson at Fordham University. Science Vol. 326, Nov. 20, 2009. See Also:
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Source: Wired: Wired Science | 19 Nov 2009 | 2:01 pm Hyperlens Sharpens Sights With SoundHigh-resolution ultrasound and sonar imaging is now possible with a new metamaterial.Source: Discovery News - Top Stories | 19 Nov 2009 | 1:30 pm The Digital Divide: Why Grandma Should Get OnlineGoing online may help seniors overcome depression.Source: Livescience.com | 19 Nov 2009 | 1:19 pm Nearly Blind Seal to Get SurgeryA monk seal scheduled to get eye surgery.Source: Livescience.com | 19 Nov 2009 | 1:15 pm Atlantis Astronauts Embark on First SpacewalkA pair of spacewalking astronauts hustled through work outside the International Space Station.Source: Discovery News - Top Stories | 19 Nov 2009 | 12:59 pm Sucking Up the StormIn New Orleans, engineers are installing a giant pump they say should keep the city dry in the event of another big hurricane. Listen to the podcast.Source: Discovery News - Top Stories | 19 Nov 2009 | 12:43 pm Carbon Dioxide: sources outpacing sinksGalloping increases in human fossil fuel emissions now appear to be outrunning the ability of the world's oceans to absorb them. The first year-by-year accounting of the oceans' role as a carbon sink shows that, even as they soak up ...Source: Discovery News - Top Stories | 19 Nov 2009 | 12:09 pm Mammoth dung clue to extinctionA study of mammoth dung is helping unravel the mystery of what caused the great mammals to die out.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 12:07 pm Extinction of Giant Mammals Changed Landscape DramaticallyNew evidence from dung rules out comet and habitat loss as culprits for mass extinction.Source: Livescience.com | 19 Nov 2009 | 12:06 pm Hobbits Are a New Human Species, Study of Fossils ConcludesIs the hobbit human debate over? I doubt it, but the below, from Wiley-Blackwell, puts a strong notch on the side of those who believe "Homo floresiensis" represents a new human species. 'Hobbits' are a new human species -- according ...Source: Discovery News - Top Stories | 19 Nov 2009 | 12:04 pm Farmer Ants Fertilize Their Gardens With Bacteria
Thanks to their vast underground fungus farms, leafcutter ants are one of Earth’s most successful species — and one secret of their agricultural success is bacteria, which the ants use like fertilizer. By farming with microbes that pull nitrogen from the air, the ants thrive in nitrogen-poor rain forest soil. Researchers say their bug-harnessing tricks might point people toward better ways of turning plants to fuel, or boosting our own crop yields. “The reason we’re able to produce such massive crops is by the massive fertilization of nitrogen in our fields,” said University of Wisconsin bacteriologist Cameron Currie, co-author of a paper published Thursday in Science. “Ants supplement their crops through symbiotic associations with bacteria.” A star of rain forest documentaries, leafcutter ants are one of about 250 ant species that subsist on farmed fungus. Most of these species live in colonies of a few thousand individuals, with tiny garden plots. Leafcutter colonies have millions of members, with leaf-fed farms yielding more than a ton of fungus every year. Some scientists estimate they account for a full four-fifths of all living, nonplant rain forest matter. Fascinated by their success, researchers have studied leafcutter gardening, but something wasn’t adding up. Though Earth’s atmosphere is nitrogen-rich, animals get their nitrogen by eating plants, or eating animals that eat plants. But rain forest foliage is nitrogen poor, as are the soils colonized by the ants. “Nitrogen is one of the elements that ultimately determines productivity,” said Currie. “The nitrogen balance in ants is way off, based on what’s predicted from their diet.”
Currie’s team investigated the mystery of where the ants were getting their extra nitrogen by raising leafcutter colonies in airtight boxes. The soil in the boxes contained normal nitrogen. But the nitrogen in the air was replaced with a nitrogen atom with a different number of neutrons, called an isotope. By measuring the levels of the isotope in fungus and ant bodies, the researchers could track whether nitrogen was coming from the soil or the air. They found that the fungus was getting nitrogen from the air. They then studied bacteria growing on the fungus, and found microbes from a genus called Klebsiella, which pulls nitrogen from the air at rates comparable to microbes that live on the roots of some plants.
“What humans do for nitrogen is mine it from other sources, and dump it on our crops,” said Schultz. But this leads to waste and pollution, “and the ants accomplish it through microbes. Who knows? Maybe humans could do something similar, and cultivate microbial communities in the soil around our crops.” And this isn’t the only trick farmers might learn from the ants. In March 2008, Schultz showed that leafcutters also use antibiotic-producing microbes to keep their gardens pest-free. Currie is studying whether nitrogen-fixing bacteria help break down the ants’ leaf cuttings into a fungally-digestible form. If so, the bacteria may suggest better ways of turning plants into biofuels. “We need to discover new enzymes, new processes, to convert plant cell walls into simple sugars that can be converted into ethanol,” he said. “Ants have been converting plant biomass into energy for millions of years.” Currie added that leafcutter ants are the subject of thousands of papers authored over the last century, “yet this critical aspect of their success was completely unknown.” “This is a well-studied natural system, and we’re still learning who the players are,” he said. “What does that say about most of the natural world, where mutalisms and associations haven’t been studied?” Images: 1) A leafcutter ant tending fungus, from Cameron Currie. 2) The nitrogen-tracking test apparatus, from Science. 3) An excavated leafcutter colony, from Science. 4) Leafcutters returning to their colony with freshly cut leaves, from Jarrod Scott. See Also:
Citation: “Symbiotic Nitrogen Fixation in the Fungus Gardens of Leaf-Cutter Ants,” by Adrián A. Pinto-Tomás, Mark A. Anderson, Garret Suen, David M. Stevenson, Fiona S. T. Chu, W. Wallace Cleland, Paul J. Weimer, Cameron R. Currie. Science, Vol. 326, No. 5956, Dec. 20, 2009. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecosystem and planetary tipping points.
Source: Wired: Wired Science | 19 Nov 2009 | 12:00 pm Clovis hunters not to blame for driving mammoths to extinctionWoolly mammoths and other giant ice-age mammals faced extinction 2,000 years before deadly speartips were invented Woolly mammoths and other large, lumbering beasts faced extinction long before early humans perfected their skills as spearmakers, scientists say. The prehistoric giants began their precipitous decline nearly 2,000 years before our ancestors turned stone fragments into sophisticated spearpoints at the end of the last ice age. The animals, which included mammoths, elephant-sized mastodons and beavers the size of black bears, were probably picked off by more inept hunters who only much later developed specialised weapons when their prize catches became scarce. "Some people thought humans arrived and decimated the populations of these animals in a few hundred years, but what we've found is not consistent with that rapid 'blitzkrieg' overkill of large animals," said Jacquelyn Gill, a PhD student at the University of Wisconsin, Madison, who led the research team. Archaeological evidence shows that humans developed advanced spearheads around 13,000 years ago. The Clovis people of North America crafted speartips with deep grooves that made wounds bleed freely. With these, hunters did not have to kill their prey on the spot, but could wait for the beasts to bleed to death. The rise of the Clovis culture was thought to coincide with the demise of the woolly mammoth and other slow-moving giants on the continent, leading many researchers to suspect the animals died at the ends of the hunters' spears. Gill's team rules this out by putting a more accurate date on the decline and fall of woolly mammoths and more than 30 other large mammals that dominated the landscape as the ice sheets retreated from North America. Among them were giant sloths the size of SUVs. To date the animals' slide to extinction, the scientists examined sediment cores from a lake in Indiana. The deepest sediments were laid down in the distant past, while more recent sediments were nearer the surface. Specifically, the scientists measured levels of a fungus that is known to thrive in the excrement of giant herbivorous mammals and nowhere else. They reasoned that more fungal spores meant more dung, which in turn reflected a larger population of roaming mammals. The sediments also held ancient pollen and charcoal dust, which gave the team clues about the predominant plant life and frequency of wildfires. Writing the US journal Science, the researchers describe how the amount of mammal dung started to fall around 14,800 years ago, long before advanced spearheads became commonplace. The animals had been almost completely wiped out a thousand years later. "We know there were people who pre-dated the Clovis culture who were butchering mammoths in the area. What we're suggesting is the declines happened before the Clovis toolkit was adopted. These earlier people had tools, but they probably weren't as sophisticated," said Gill. Chris Johnson, a population ecologist at James Cook University in Queensland, Australia, said the shortage of mammoths and other easy targets might have forced early humans to improve their weapons. "People were still hunting them but this was more challenging, so they developed somewhat better tools for the job," he said. Another theory, that the larger beasts were wiped out by an asteroid strike around 13,000 years ago, also looks unlikely in view of the latest study. By improving their hunting techniques, early humans seem to have played a major role in finishing off the woolly mammoths and nine other mammal species that weighed over a tonne. The study is among the first to reveal the environmental consequences of such a catastrophic decline in species. Pollen and charcoal recovered from the sediment cores show that wildfires became far more common and that the variety of plant life changed dramatically, as the nutritious and easily digestible trees and shrubs that were eaten by the mammals grew back. "For the first time we've got a linkage between this major ecological event, the disappearance of these large animals, and evidence of the environmental consequences," said Jack Williams, a co-author on the study. 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 | 19 Nov 2009 | 12:00 pm False positive on breast cancer | Sarah WildmanA panel's recommendation that American women need fewer mammograms would mean more deaths from breast cancer In the US we've heard the refrain for two decades: early detection saves lives. But this week a federal advisory board decided that while that slogan wasn't false, in the case of breast cancer, it just wasn't true enough. After years of pink ribbons and breast cancer marches and admonishments to examine our breasts, this week the US Preventative Services Task Force bucked conventional wisdom (and the American Cancer Society) claiming that the number of women saved by early detection through mammography was not enough to warrant the recommendations nearly every schoolchild can recite: a mammogram a year after age 40. Citing anxiety – real, as every woman who has waited for her mammogram results can attest – caused by false positives and unnecessary (and, yes, again anxiety provoking) biopsies, the federal agency announced that henceforth the guidelines would advise women to seek mammograms only after age 50, and only then every two years. In other words: the NHS model. Women in America have long had one edge over their British counterparts – a recommendation that we be screened annually, a full decade before our friends in London and elsewhere, beginning at age 40, for breast cancer. American women, more likely to pick up their cancers early, have a 97% chance of survival five years post-detection. Our sisters across the pond? Only a 78% chance. Since 1990, the number of American women dying of breast cancer has dropped by 30%. As Dr Angela Sie, director of imaging at the breast centre at Long Beach Memorial Hospital, told the Los Angeles Times, changing the rules "would be a huge step backwards for women's health in this country." Certainly, my family is pleased these recommendations didn't exist twenty years ago. My mother, not to put too selfish a spin on it, was a beneficiary of the previous regime. Her first breast cancer, caught small – terrifying but manageable – at age 43. Her second – again picked up on a mammogram – at age 49. A double mastectomy and radiation, no picnic, as we Yanks like to say, to be sure, but she's still here, still calling me four times a day, still clomping after her dog at night, still bugging my dad in the morning. For this I am grateful we were insistent on mammography. But for this I worry for all those whose mothers and sisters and selves will no longer benefit. The doctors of the task force – which, notably, contains not a single oncologist – have reassured the public that women in higher risk categories would be urged to have conversations with their doctors about whether their screening should start sooner. Said Dr Diana Petitti, deputy chair of the task force: that women should not be screened in their 40s…. We're saying there needs to be a discussion between women and their doctors." But this raises still more questions. For one, who are those women? African American women? Ashkenazi Jewish women? All lesbians? Each is a group that has a slightly higher risk than the general population. Do we know all the risk groups? Does everyone know their family history? And secondly, what will this new recommendation mean for our deeply flawed insurance system? Currently, the state-funded Medicare programme is required to cover an annual mammogram. Will insurance companies begin to see this as another exclusion they can write into their murky by-laws? How long will insurance continue to cover mammograms before the age of 50? The water is muddied. A phenomenally successful public service campaign scuttled. And for what? What is risk? Who are we shunting aside in the hopes of preserving calm over screening? Screen women in their 40s, according to the Annals of Internal Medicine, and you see a 16% mortality reduction – 6.1 deaths per 1,000 women are saved. Some 40,000 women die of breast cancer every year, and cancer is the leading cause of death of women in their 40s. (For the record, breast cancer is about 100 times less common among men.) Consider that the Food and Drug Administration is considering banning raw oysters from the Gulf of Mexico to save the lives of 15 people who die each year from bacteria in contaminated oysters. The shellfish industry is up in arms. But for the families of those 15, treating those oysters or forgoing them is worth the federal effort. Fifteen deaths from oysters. How many thousands from breast cancer? No wonder the Obama administration backed away from the panel recommendation. Beyond potentially complicating the already complicated end-game for health-care reform in the US Congress, who wants to tell a family that their mother wasn't statistically significant enough to save? 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 | 19 Nov 2009 | 12:00 pm Letter: Stanley Ellis obituaryBrian MacDonald writes: I had the privilege of using Stanley Ellis (obituary, 14 November) a number of times as an expert witness when I was an investigator for HM Customs. I first met him in 1989, when I gave him a short lift to Isleworth crown court. We spoke only briefly during the car journey, and as he got out of my car, he surprised me by asking which part of the Wirral peninsula I was brought up in (astonishing, as I had left the Wirral nearly 30 years earlier). Stanley was enthusiastic and meticulous about his specialism and fair in his opinions. He will be missed. 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 | 19 Nov 2009 | 11:55 am Three New Ancient Crocodile Species Fossils FoundA 20-foot-long crocodile with three sets of fangs -- like wild boar tusks -- roamed parts of northern Africa millions of years ago, researchers reported Thursday.Source: Discovery News - Top Stories | 19 Nov 2009 | 11:34 am Shuttle Atlantis arrives at space stationCAPE CANAVERAL, Florida (Reuters) - Space shuttle Atlantis arrived at the International Space Station on Wednesday to deliver spare parts needed to keep the outpost operational after the shuttles' retirement next year.Source: Reuters: Science News | 19 Nov 2009 | 11:32 am Fear and the Large Hadron Collider | Euclides MontesFrom as far back as discovery of fire, science has made us anxious. We must harness fear's power, not be consumed by it No sooner was it announced that the Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (Cern) was ready to be fired up again, than the buzz of apprehension about its associated dangers had started rippling through the net once more like little whispers on the wind. But why are so many so scared of what scientists expect to be one of the greatest scientific breakthroughs of the decade? After all, this is an experiment that can give us an insight into the very nature of what the universe itself is made. A question we've been asking ourselves since the beginning of time. Yet, for every mention of Hawking radiation and Higgs boson particles you'll find two people prophesying dimensional rips and world-destroying black holes. Otherwise known as apocalypse. But is the fear justified? Scientists have assured us that the chances of a world-threatening scenario radiating outward from Switzerland on Friday are not only minimal, but beyond all reasonable doubt, thanks to years of research, testing and planning. So, I ask again, why so much fear? I feel the answer actually transcends Cern and its underground experiment, and goes all the way to the heart of the relationship that humans have had with science throughout the ages. Make no mistake, it is truly a love affair of Shakespearian proportions. Fire dragged us down from the trees but it then shone a light into the unknown, and so the fear was born. Perhaps we shouldn't be surprised at the renewed calls for greater caution over the LHC. Fear has always been a travel companion of scientific progress. Daguerreotypes were met with deep suspicion when first introduced. Even now in the age of Flickr and smartphones, there are those who still fear the soul-snatching power of a photograph. This deep-rooted fear of what lies just beyond us – both physically and intellectually – has characterised humanity's thirst for knowledge as well as its reaction to the advancements the quest has brought with it. But while it is important to acknowledge "fear" as an important part of scientific progress, left unchecked it can be a dangerous thing. Let's not forget that just last week Nasa had to reassure a large proportion of a very scared American population that in spite of the clever ad campaign for Roland Emmerich's latest blockbuster, 2012 will most likely be just another year (and not the end of the world). And this is the crux of the matter: the more the world around us is explained and understood in scientific terms, the more questions we unearth. Science doesn't know all the answers and many fear that in its desire to find them, science itself might end up being a dangerous thing. "Playing god" is a common accusation levelled at scientists. But I don't believe this is a position we should take. It is our ingenuity in finding the answers to the questions that perplex us that distinguishes us from animals. Giving in to the fear and asking of science to stop going forward would be to fight against the very thing that made us human in the first place. So rather than being consumed by the fear, we should instead be using it to spur us on in our search for knowledge and I, for one, will be eagerly following the events on Friday. I hope LHC kicks off with a bang … a big bang. 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 | 19 Nov 2009 | 11:30 am Is the Tuna in Your Sushi Endangered?This just in from the American Museum of Natural History: unknowlingly consuming endangered tuna A Genetic Tool Uncovers the Species of Tuna Plated in Sushi Restaurants While most of us would never willingly consume a highly endangered species, doing so ...Source: Discovery News - Top Stories | 19 Nov 2009 | 11:22 am Snails: More Protein, Less Expensive Than BeefFrom Inderscience: A nutritionist in Nigeria says that malnutrition and iron deficiency in schoolchildren could be reduced in her country by baking up snail pie. In a research paper to be published in the International Journal of Food Safety, Nutrition ...Source: Discovery News - Top Stories | 19 Nov 2009 | 11:16 am IBM Cat Brain Computer is Me-WowIBM announced this week that it has a computer system that can simulate the thinking power of a cat's brain with 1 billion neurons and 10 trillion synapses. At just 4.5 percent of a human brain, the computer can sense, ...Source: Discovery News - Top Stories | 19 Nov 2009 | 10:57 am US, China Look to Expand Space PartnershipWhether the United States and its partners in the International Space Station program will get their money’s worth out of the $100 billion endeavor is still to be determined, but there’s one point even the skeptics concede: it’s been a ...Source: Discovery News - Top Stories | 19 Nov 2009 | 10:56 am In pictures: Galloping crocs unearthed in the SaharaFossil hunters have discovered the remains of primitive crocodiles that could not only swim but also 'galloped' on land Source: Science news, comment and analysis | guardian.co.uk | 19 Nov 2009 | 10:28 am The case for a complete DNA database | Gavin PhillipsonAt the moment, the arbitrary process of adding to the database breeds injustice. Perhaps we owe it to society to all be included The national DNA database is once again being hotly debated. The government is now proposing that the DNA profile of innocent people (those arrested but never convicted) should be kept for only six years, instead of indefinitely, as is the case now. This late and mealy-mouthed concession is unlikely to satisfy the European court of human rights, but it forces all of us to consider the important, long-term question. Given that this technology is here to stay, as a crucial means of solving crimes, who should be on the database? The problem with the government's approach is that it uses the criterion of whether you happen to have been arrested – even for a fairly trivial offence. This means that ethnic minorities, subject to disproportionately higher levels of arrest, end up over-represented: it's estimated that 40% of black men are on the database. Because being on the database is linked with having been arrested, it becomes a stigma, a taint of suspicion. It also means that when DNA evidence is recovered from a crime scene, whether there is a match depends, arbitrarily, upon whether the perpetrator happens to have been arrested before. Justice becomes a matter of chance. There are also huge problems with access to the database: at present 56 non-police bodies have access, including BT and the Association of British Insurers. This is ridiculous and wrong: since the justification for the database is fighting crime, access to it should be strictly confined to crime-fighting agencies and its use to generating matches from crime-scenes. But what of the much longer term? One eventual solution we should consider – if the above safeguards were put in place – is a system in which everyone is on. The logic of the proposal arises from two propositions: (a) DNA is an invaluable technology in solving serious crime; but (b) as soon as you confine it to certain classes of people you produce arbitrariness and injustice. If everyone is on, everyone is equally treated: it would cease to be a stigma and instead becomes an honourable means by which everyone makes a contribution towards protecting the vulnerable from violent crime. And of course it would mean that the database has comprehensive coverage, radically increasing its effectiveness. Many will argue that this would be a disproportionate intrusion into our privacy. I have great respect for that view, though I don't think it's quite as clear-cut as this: if we are talking not about retaining DNA samples, but only the digital profile, and if access and use were to be strictly confined as suggested above, then I don't think the intrusion into privacy is particularly grave, while the societal gains in solving and deterring appalling crimes are very significant. Sceptics doubt the effectiveness of DNA matching, and invoke fears of false matches and planted samples. As to effectiveness, a 2006 academic study found that the overall detection rate for crimes of 23.5% rises to 38% where DNA is successfully recovered; in domestic burglary, the detection rate rises more than threefold, from 14% to 48%. One estimate is that DNA-matching helps solve 400 murders a year, about 800 rapes and serious assaults and about 8,000 burglaries. And the uncomfortable fact is that some of these crimes have been solved using DNA from the innocent on the database: 114 murders, 55 attempted murders, 116 rapes and 119 aggravated burglaries, according to one estimate. US prosecutors have seen significant success in using DNA evidence to convict and deter rapists. As to false matches, thus far, the fears are exaggerated: a 2002 study found only two cases worldwide. Of course DNA evidence can be planted; but so can drugs or stolen goods; confessions are frequently unreliable; witnesses can be intimidated or bribed; even honest eye-witness accounts are so unreliable that juries have to be warned about them. DNA matching is generally much less prone to producing misleading evidence than other methods; real dangers arise only if it is thought that it is some kind of magical, infallible crime solver. It's not as simple as sinister Orwellian government database v virtuous civil libertarians: it's a real dilemma that we should try to think about dispassionately and with a full grasp of the facts. 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 | 19 Nov 2009 | 10:05 am 'Big Bang' machine to re-startThe Large Hadron Collider (LHC) could be re-started in the early hours of Saturday morning at the earliest, officials have said.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 9:27 am Light Shed on Mysteries of Deadly JellyfishClues to the a jellyfish's deadly sting may lead to an antidote.Source: Livescience.com | 19 Nov 2009 | 8:56 am Corps blamed for Katrina floodsA US judge rules that negligence by army engineers led to massive flooding in part of New Orleans as Hurricane Katrina struck in 2005.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 8:44 am Fossil hunters unearth galloping, dinosaur-eating crocodiles in SaharaThe primitive crocodiles, which lived 100m years ago, were good swimmers but were also capable of galloping Fossil hunters have uncovered the remains of primitive crocodiles that "galloped" on land and patrolled the broad rivers that coursed through north Africa one hundred million years ago. The skeletons of five creatures that walked with dinosaurs – and ate them – were unearthed in remote and rocky regions of what are now Morocco and Niger during a series of expeditions in the Sahara desert. Three of the crocodiles are new species and include Kaprosuchus saharicus, a 6.5m-long beast with three sets of dagger-like tusks and an armoured snout for ramming its prey. Another species, Laganosuchus thaumastos, was of similar length but had a pancake-flat head and is thought to have lurked in rivers with its jaws open, waiting for unsuspecting fish to pass. The most striking feature the beasts have in common was revealed by their bone structure, which suggests they were efficient swimmers but that when they clambered ashore they were also capable of galloping across the plains. Modern crocodiles crawl on their bellies because their legs sprawl out to the side. "My African crocs appeared to have had both upright, agile legs for bounding overland and a versatile tail for paddling in water," writes Paul Sereno, a palaeontologist at the University of Chicago, in National Geographic Magazine. "These species open a window on a croc world completely foreign to what was living on northern continents." The third new species, Araripesuchus rattoides, was only a metre long and probably used a pair of buckteeth in its lower jaw to dig for grubs. The other two crocodiles unearthed during the expedition are known species. One had a wide, overhanging snout containing sensory areas that it used to sniff out prey in shallow waters. The other had a soft, dog-like nose and is thought to have been extremely agile. Most of the fossils were found near the site where, in 2001, Sereno uncovered a 12m-long crocodile that lived 110m years ago. The beast, nicknamed SuperCroc, weighed around eight tonnes. The latest fossils are described in the journal ZooKeys. "We were surprised to find so many species from the same time in the same place," said Hans Larsson, a palaeontologist at the University of Montreal, who took part in the expedition. "Each of the crocs apparently had different diets, different behaviours. It appears they had divided up the ecosystem, each species taking advantage of it in its own way." The expedition was sponsored by National Geographic, which airs a documentary about the discoveries, When Crocs Ate Dinosaurs, at 5pm on Sunday 20 December on the Nat Geo Wild channel. 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 | 19 Nov 2009 | 8:40 am Strange Ancient Crocodiles Swam the SaharaOdd bunch of crocs lived alongside dinosaurs.Source: Livescience.com | 19 Nov 2009 | 8:31 am Sex and evolution on primary curriculumPrimary pupils in England will have to study evolution, the chronology of British history and sex education, under a new curriculum for five- to 11-year-olds announced yesterday. Ministers said they had moved to strengthen the place of British history in the primary syllabus after claims that the new system, which replaces 13 individual subject areas with six thematic "areas of learning", would water down traditional subjects. But the new curriculum, while including wide references to how pupils should develop a "chronological understanding" of British history, has no reference to the Victorians, Tudors or world wars, because ministers insisted they did not want to prescribe every lesson to primary schools. Earlier draft versions of the curriculum, seen by the Guardian, specifically included an option for pupils to study the Victorian era or a world war. It also suggested they should learn how to use Twitter, a reference that hassince been removed. The plans have triggered a furious row over whether the government is downgrading history which has stretched as far as Prince Charles. Bernice McCabe, co-director of the Prince's Teaching Institute, said that the prince was "passionate that these subjects should remain there in the curriculum". But a consultation on the proposals, published yesterday, suggested that 70% of more than 1,000 teachers, 500 pupils and 375 parents polled supported the plans and thought they would give schools more flexibility about what they teach. For the first time, every pupil will have to learn about evolution, after successful lobbying by the British Humanist Association and scientists to have it included in the curriculum. Pupils will learn the basics of adaptation of simple organisms to prepare them for more in-depth knowledge at secondary school. A new personal, social and health education element to the curriculum is made compulsory for the first time – though parents will be able to withdraw their children from the sex education classes if they choose. The new curriculum, designed after a widespread consultation process by the government's chief primary advisor Sir Jim Rose, will come into effect from September 2011. The schools minister, Vernon Coaker, said the plans would give schools more freedom and flexibility to design lessons and involved less top-heavy prescription. "What and how our children learn lies at the heart of our policies to raise standards. We've seen that an inspiring and rigorous curriculum can transform failing schools, which is why these plans are based on the very best practice from the country's top-class teachers," he said. 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 | 19 Nov 2009 | 7:12 am In picturesHelena Christensen documents climate changeSource: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 6:25 am Mad Science? Growing Meat Without AnimalsCow-less steak could mean saying goodbye to contamination worries.Source: Livescience.com | 19 Nov 2009 | 6:03 am Energy-saving bulbs 'get dimmer'Energy-efficient light bulbs lose on average more than a fifth of their brightness over their lifetime, a study finds.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 4:36 am Don't look down: Baby ibex's perilous escape caught on cameraAmazing footage of a baby ibex's perilous escape from a fox is captured on film by a BBC natural history cameraman.Source: BBC News | Science & Environment | UK Edition | 19 Nov 2009 | 3:02 am
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