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 The 365 million-year-old fossil skull, shoulders and part of the pelvis of the water-dweller, Ventastega curonica, were found in Latvia, researchers report in a study published in the journal Nature. Even though Ventastega is likely an evolutionary dead-end, the finding sheds new details on the evolutionary transition from fish to tetrapods. Tetrapods are animals with four limbs and include such descendants as amphibians, birds and mammals. While an earlier discovery found a slightly older animal that was more fish than tetrapod, Ventastega is more tetrapod than fish. The fierce-looking creature probably swam through shallow brackish waters, measured about three or four feet long and ate other fish. It likely had stubby limbs with an unknown number of digits, scientists said. "If you saw it from a distance, it would look like a small alligator, but if you look closer you would find a fin in the back," said lead author Per Ahlberg, a professor of evolutionary biology at Uppsala University in Sweden. "I imagine this is an animal that could haul itself over sand banks without any difficulty. Maybe it's poking around in semi-tidal creeks picking up fish that got stranded." This all happened more than 100 million years before the first dinosaurs roamed Earth. Scientists don't think four-legged creatures are directly evolved from Ventastega. It's more likely that in the family tree of tetrapods, Ventastega is an offshoot branch that eventually died off, not leading to the animals we now know, Ahlberg said. "At the time there were a lot of creatures around of varying degrees of advancement," Ahlberg said. They all seem to have similar characteristics, so Ventastega's find is helpful for evolutionary biologists. Ventastega is the most primitive of these transition animals, but there are older ones that are oddly more advanced, said Neil Shubin, professor of biology and anatomy at the University of Chicago, who was not part of the discovery team but helped find Tiktaalik, the fish that was one step earlier in evolution. "It's sort of out of sequence in timing," Shubin said of Ventastega. Ahlberg didn't find the legs or toes of Ventastega, but was able to deduce that it was four-limbed because key parts of its pelvis and its shoulders were found. From the shape of those structures, scientists were able to conclude that limbs, not fins were attached to Ventastega. One question that scientists are trying to figure out is why fish started to develop what would later become legs. Edward Daeschler, associate curator of vertebrate zoology at the Academy of Natural Sciences in Philadelphia, theorizes that the water was so shallow that critters like Ventastega had an evolutionary advantage by walking instead of swimming.
 Decades of chemical pollution have damaged the ozone layer of the upper atmosphere that shields Earth from the harmful effects of the sun's ultraviolet rays, each summer eating a hole over the South Pole that expands to nearly the size of Antarctica. But since 1996, when an international treaty banned the culprit chemical refrigerants and propellants (known as CFCs, or chlorofluorocarbons), the size of the seasonal tear has been shrinking—and scientists predict it may stop forming by the end of this century. That is not just good news for the ozone hole, it is also good news for the climate. Atmospheric scientists note in a new study published in Science that sewing up the rift in the ozone (a type of oxygen) layer may help heal another environmental woe: climate change. The reason: closing the gash may affect the flow of winds known as the westerlies around Antarctica, which impact everything from the extent of sea ice to the location of deserts in the Southern Hemisphere. According to scientific studies and mathematical models developed for the United Nations Intergovernmental Panel on Climate Change (IPCC)—which last year determined that the changing climate is largely a man-made danger—global warming has shifted these winds toward the poles, altering weather patterns throughout the Southern Hemisphere. The new research shows that mending the ozone may reverse warming in Antarctica and, potentially, the globe. "The winds drive everything," says study author Lorenzo Polvani, an atmospheric scientist at Columbia University, "locations of storms, dry zones and deserts, the ice and the ocean circulation as well as the carbon uptake of the oceans." For decades, these winds have been speeding up near Antarctica; repairing the ozone would weaken the winds, he says, and shift them back toward the equator, affecting weather in the entire Southern Hemisphere, including Antarctica as well as Australia, parts of Africa and South America. This also means Earth's southernmost continent might experience warming in future as the winds continue to shift and allow relatively warmer air to cover it, potentially speeding the melting of ice shelves. In addition, if there were no hole, the replenished ozone would trap even more heat as greenhouse gas concentrations also rise, according to Polvani. Atmospheric scientist Judith Perlwitz of the University of Colorado at Boulder and her colleagues reached a similar conclusion, published recently in the journal Geophysical Research Letters. But she notes that none of the models on which scientists base these predictions tell the whole story, because they have yet to include all possible variables in their calculations. For instance, she says, no one has factored in the role that the ocean—critical to the regulation of Earth's temperature—would play if the ozone hole is closed. Perlwitz says that computer simulations including ocean impacts are now being run, and could help scientists better predict the potential consequences of global warming and the changing ozone—and what must be done to limit the damage.
 Researchers say the Iron Age man may have been a soldier serving on the Roman Empire's northern frontier or a descendant of female slaves transported from the Middle East. The Roman Empire at the time stretched as far as the Middle East, while Roman legions were based as far north as the River Elbe in northern Germany. The study analyzed 18 well-preserved bodies from two burial sites dating from 0 to A.D. 400 in eastern Denmark. The sites were originally excavated some 20 years ago. Mitochondrial DNA, which provides a genetic record of an individual's maternal ancestry, was taken from teeth by a team led by Linea Melchior of the Institute of Forensic Medicine at the University of Copenhagen. One skeleton had a type of DNA signature—known as a haplogroup—closely associated with the Arabian Peninsula, according to Melchior. "It's especially found among some Bedouin tribes, but it has also been found in the southern part of Europe," the researcher said. Iron Age Grave The skeleton came from Bøgebjerggård, an Iron Age site on the southern part of the island of Sjælland (Zealand). The bodies likely belonged to poor farmers, the team said. Other unusual haplogroups were identified, including one representing a prehistoric European lineage which today is found in only about 2 percent of Danes, Melchior said. "It may have been one of the ancient Nordic types which has been diluted by later immigrations from Scandinavia and Germany," she said. In contrast, the other burial site, at nearby Skovgaarde, contained bodies with a genetic signature common to modern Scandinavians, the study found. "They were typically of a Nordic type and the diversity is lower," Melchior said. This group consisted mainly of women and was distinguished by rich grave goods, including finely made rings, necklaces, and ornate hairpins. "You can see they were dressed up very nicely with beautiful jewelry before being buried," Melchior said. The Skovgaarde burials are thought to represent the elite of society—people the researchers think arrived from elsewhere in Scandinavia. The findings, published in November in the American Journal of Physical Anthropology, are part of a wider study that suggests Denmark's ancient populations were much more diverse genetically than they are today. Reliable DNA results have been obtained for 56 individuals from the late Stone Age through medieval times, Melchior said. "At all the sites we have investigated in Demark we have found rare [genetic] types and types that are not common or present in Europe today," she said. "When we go back in time we find much higher diversity," the Melchior added. "It was quite surprising that the lowest diversity was found among Danes of the present day." One possible explanation put forward by the team is that certain groups were more vulnerable than others to medieval outbreaks of bubonic plague, most notably the Black Death, which alone wiped out around a third of the European population between 1347 and 1351. Such a theory has been proposed by another recent study, which recorded a similar loss of genetic diversity in English people. Researchers, including Rus Hoelzel of the School of Biological and Biomedical Sciences at Durham University, U.K, found that during the medieval period one particular haplogroup in England became much more widespread. This may reflect the fact that families who shared certain genes survived the plague much better than others, said Hoelzel , who was not involved in the Danish study. "Plague, given the timing, seems a strong candidate, though it isn't the only one," he said.
 "This amphibian is from near to the point where frogs and salamanders first split," said lead researcher Jason Anderson, a vertebrate paleontologist at the University of Calgary in Canada. "This is kind of an early frog-amander." The finding, detailed in journal Nature, supports the idea that frogs and salamanders evolved from one ancient amphibian group called temnospondyls. Like modern salamanders, the fossil of Gerobatrachus has two fused bones in its ankle. And like modern frogs, the frog-amander sports a large ear drum, or tympanic ear, which Anderson said the ancient amphibian likely used for hearing calls from mates. "I suspect that many of the temnospondyls have a similar sort of [tympanic ear] system," says Anderson. "But of course unless we were able to build a time machine and go back and listen to these guys call, we won't know for sure." Rather than hopping, this amphibian likely walked on land and swam in water, with the ability to lunge after prey, Anderson said. In fact, along the evolutionary history of amphibians, frogs didn't begin hopping until the Jurassic or Triassic period. (The most definitive hopping frog fossil is dated to the Triassic, which spans from 248 million to 206 million years ago.) "It was found in sediments from a quiet pond with a lot of fish fossils, but I suspect it was equally comfortable on land or in water," Anderson said. The fossil also showed several tiny teeth that had a specialized trapping feature seen in all modern amphibians at some point in development. The teeth are able to hinge inward when catching prey. "It allows food to go in, but it can't get back out," Anderson said. The new species, spanning less than 5 inches (12 cm) from nose to tip of tail, provides a marker of when frogs and salamanders went their separate ways along the evolutionary path toward modern forms. "With this new data, our best estimate indicates that frogs and salamanders separated from each other sometime between 240 [million] and 275 million years ago, much more recently than previous molecular data had suggested," said study team member Robert Reisz of the University of Toronto Mississauga. Earlier this week, a separate team announced finding a yellow tree frog in Panama that also had transitional features.
The surveyed teachers spent an average of 13.7 classroom hours per year on general evolutionary processes in their biology classes. The majority spent no more than five hours a year on human evolution, and 17 percent did not cover it all. Only two percent of teachers did not teach about evolution, human or otherwise, at all. Thirteen percent of teachers thought an excellent biology course could exist without mentioning Darwin or evolutionary theory. Twenty-five percent of teachers said that they devoted at least one or two classroom hours to creationism or intelligent design. About half of this subset—one in eight biology teachers—taught it not in critique but as a “valid, scientific alternative to Darwinian explanations for the origin of species” and one that “many reputable scientists” endorse. Sixteen percent of all teachers surveyed believe personally in the “young earth” story of origins: that human beings were created by God in their present form at one time within the last 10,000 years. This creates an problem for our education system because the students are being brainwashed. After the graduation these students are having hard time facing the reality. The survey, which was conducted by a team of Penn State political scientists last spring, assessed 939 randomly sampled U.S. biology teachers. It appears in PLoS Biology.
Belonging to the same religion also gives people a common identity, sometimes across countries and continents. Of course, that spirit of community has also been forced upon people as a way to change their identity, if they want to or not. And as anyone who has attended a bris, a First Holy Community, or a wedding knows, religion has always been instrumental in marking the passage of individuals through the life course from baptism through funerals, something that people love to do. For some, religion also binds their anxiety because it answers unanswerable questions about death, the afterlife, and why in the world we are here in the first place. Religion can also be a place of solace during the hard times, a place to find hope when times are hopeless. In other words, religion is often essential for our psychological well-being. Evolutionary biologist David Sloan Wilson of Binghamton University and others have also pointed out that religion can also be adaptive. If cooperation and group identity helps individuals stay alive and pass on genes, then religion is evolutionarily important, even if we made it up. The recent research, published in the online FASEB Journal (Federation of American Societies for Experimental Biology) on May 2, suggests that religion, or at least many religious rituals, might also have another evolutionary, or biological function. Along with the group support, the embracing identity and the place to pray when times are bad, some religions are also doling out a bit of a psychotropic drug that helps the mind find peace. Under the influence of a good snoot full of incense, mice in scary situations, such as being put in a swimming pool, remain calm, anxiety-free. At the alter, too, people feel the same sense of peace that comes from either the comforting words of the clergy, or from the intoxicating, brain altering, smell of incense.
 The next U.S. president needs to elevate the role of the White House science adviser In the wake of the near panic over the launch of Sputnik in 1957, President Dwight D. Eisenhower appointed James Killian, the president of the Massachusetts Institute of Technology, to become the first special assistant to the president for science and technology. Ever since, the relationship between the nation’s chief executive and the White House’s resident authority on nuclear fission, the workings of DNA and the greenhouse effect, among an array of topics, has had its highs and lows. To be sure, advice has flowed freely at times. Eisenhower consulted frequently with Killian and other scientists, and in the Kennedy years Jerome Wiesner, another M.I.T. president, helped to coordinate the government’s response to the publication of Rachel Carson’s Silent Spring, a book that spurred a national grassroots environmental movement by pointing out the dangers of pesticides. Just as often the adviser’s position has tilted toward irrelevance. Richard M. Nixon went so far as to abolish the job altogether, along with the President’s Science Advisory Committee, which had recommended against going ahead with a supersonic transport program, advice that the ill-fated 37th president did not want to hear. (The U.S. Congress restored the position in 1976.) The tenure of George W. Bush marks a new nadir. On the few science-related issues the administration has cared about—stem cells and climate change were on the short list—it had largely set its course before the arrival of its new science adviser John H. Marburger III some nine months after Bush first took office. The administration, moreover, stripped the job of the title “special assistant to the president,” a reminder that the adviser would never be part of the inner circle. Nevertheless, hopes rose with the appointment of the well-regarded physicist and former head of Stony Brook University and Brookhaven National Laboratory. “As both scientist and administrator, John H. Marburger III tries to bring needed perspective into a White House not thought to be particularly interested in science,” read a headline for a profile published in Scientific American in June 2002. In the ensuing years, Marburger has disappointed. Much of his public persona has been as an apologist for the Bush team, trying to rebut charges from scientists, Congress and the media that the administration has engaged in a “war on science” by systematically distorting or suppressing science-related reports and politicizing federal advisory committees. We can only hope that the next president, whether Democrat or Republican, will not relegate the science adviser—and the entire scientific endeavor—to the status of afterthought. Once elected, the new chief executive should hire a leading scientist, perhaps one with Marburger’s credentials though not with his compliant, technocratic demeanor. In collaboration with the rest of the community, the official should be allowed to assume a prominent, unimpeded role in helping to influence the crafting of policies that address climate change, missile defense and stem cells.
 NASA plans to launch millions of names into space as part of the Kepler Mission to find planets in a habitable zone beyond our solar system. "This mission will provide our first knowledge of Earth-like planets beyond our solar system," Kepler Mission principal investigator William Borucki said in a news announcement. NASA will launch millions of names into space through a program aimed at encouraging public participation in space exploration. Anyone can submit their name and their home state or country and be included on a DVD that will launch beyond our solar system as part of NASA's Kepler Mission next year. Participants can include an explanation, of up to 500 words, explaining why they think the mission is important. NASA has launched names into space before, but the Kepler spacecraft will search for planets in a habitable zone beyond our solar system. According to NASA scientists, habitable worlds are most likely found on large, rocky planets that are up to ten times the size of Earth and contain plate tectonics. Plate tectonics play a critical role in determining the rate of cooling of a potentially habitable planet by creating the optimum temperature ranges for the development of intelligent animal life -as continents grow, planets cool. The researchers found that super-Earths, or planets up to ten times the size of the Earth are the best places to find extraterrestrial life. These planets contain a solid inner core that is surrounded by a liquid mantle, and on top a crust. What is seen as critical to life on one of these large extra-solar planets (exoplanets)—or planets circling a star other then the Sun—is the presence of plate tectonics. "This mission will provide our first knowledge of Earth-like planets beyond our solar system," Kepler Mission principal investigator William Borucki said in a news announcement. The names included in the exploration will be recorded on a DVD, mounted outside the spacecraft, posted on the Kepler Mission Web site, and sent to the Smithsonian Institution's National Air and Space Museum. Participants will be able to print certificates stating that their name has been included on the list of names launched into orbit around the sun. Participation and the certificates, from the Kepler Mission Web site, are free. To submit names and learn more about the Kepler Mission, visit: http://kepler.nasa.gov/
 Crystal skulls are not uncommon or terribly mysterious. Thousands are produced every year in Brazil, China, and Germany. But there are a handful of these rather macabre objects that have fueled intense interest and controversy among archaeologists, scientists, spiritualists, and museum officials for more than a century. There are perhaps a dozen of these rare crystal skulls in private and public collections. Some are crystal clear, others of smoky or colored quartz. Some are actual human size and of very fine detail, while others are smaller and less refined. All are believed to originate from Mexico and Central America. Many believe these skulls were carved thousands or even tens of thousands of years ago by an ancient Mesoamerican civilization. Others think they may be relics from the legendary island of Atlantis or proof that extraterrestrials visited the Aztec sometime before the Spanish conquest. Recent electron microscope analyses of skulls by the British Museum and the Smithsonian Institution revealed markings that could only have been made with modern carving implements. Both museums estimate that their skulls date to sometime in the mid- to late 1800s, a time when public interest in ancient cultures was high and museums were eager for pieces to display. Its examinations and the fact that no such skull has ever been uncovered at an official archaeological excavation led the British Museum to extrapolate that all of the famed crystal skulls are likely fakes. There is passion on both sides of the issue, and the fact remains that no one knows for sure who made these skulls and when. And since there is currently no way to accurately determine the age of such inorganic objects, the mystery will likely continue. In fact, it's sure to get a boost in 2008 with the release of the action-adventure sequel Indiana Jones and the Kingdom of the Crystal Skull.
Now for the first time, scientists reveal a primate other than humans can also express a variety of messages by combining sounds into different sequences. The finding suggests this level of language might have occurred far earlier in evolution than before thought. By three years of hard work trailing male putty-nosed monkeys, the researchers found the primates produced series of alarm calls that differed depending on the threat involved. For instance, a series of calls made up of "pyows" are a common response to leopards, while series of "hacks" followed by "pyows" are given to crowned eagles. By playing back recordings of calls at monkeys, Klaus Zuberbühler, Arnold and their colleagues at the University of St. Andrews in Scotland unexpectedly found that males could arrange hacks and pyows to convey at least three different kinds of information to other monkeys — the event they witnessed, the identity of callers, and even whether they intended to travel. Scientists had suggested that stringing different sounds together into complex ideas occurred relatively late in human evolution, speculating that such combinations only happened when doing so became easier than adding new signals to a large, unwieldy repertoire."Our research shows that these assumptions may not be correct," Zuberbühler said. "Putty-nosed monkeys have very small vocal repertoires, but nevertheless we observe meaningful combinatorial signaling." Why They do It Most primates are actually limited in the number of signals they can physically produce because of their lack of tongue control. "The only way to escape this constraint may be to combine the few calls they have into more complex sequences," Zuberbühler said. "In other words, it may be 'harder' for non-human primates to evolve large repertoires than to evolve the ability to combine signals. Hence, the evolution of combinatorial signaling may not be driven by too many signals but rather by too few." Since the ancestors of humanity genetically diverged from ancestors of these monkeys some 25 million years ago, these findings suggest that some of the core abilities required for human language may be much older than had been thought. Still, "it is not clear at this point whether the communication system we describe is an isolated case — a freak of nature, so to speak — or whether it represents a more general pattern underlying primate vocal behavior," Zuberbühler said. "There are over 200 species of primates, but only a very small number of species has been studied with regards to their communication skills."
This machine could not only serve as the foundation of a powerful computer, but also serve as the controlling element of complex gadgets such as microscopic doctors or factories, scientists added. The device is made of a compound known as duroquinone. This molecule resembles a hexagonal plate with four cones linked to it, "like a small car," explained researcher Anirban Bandyopadhyay, an artificial intelligence and molecular electronics scientist at the National Institute for Materials Science at Tsukuba in Japan. Duroquinone is less than a nanometer, or a billionth of a meter large. This makes it hundreds of times smaller than a wavelength of visible light. The machine is made of 17 duroquinone molecules. One molecule sits at the center of a ring formed by the remaining 16. The entire invention sits on a surface of gold. How it Works Scientists operate the device by tweaking the center duroquinone with electrical pulses from an extremely sharp electrically conductive needle. The molecule and its four cones can shift around in a variety of ways depending on different properties of the pulse — say, the pulse's strength. Since weak chemical bonds link the center duroquinone with the surrounding 16 duroquinones, each of those shifts too. Imagine, for instance, a spider in the middle of a web made of 16 strands. If the spider moves in one direction, each thread linked to it experiences a slightly different tug from all the others. In this way, a pulse to the central duroquinone can simultaneously transmit different instructions to each of the surrounding 16 duroquinones. The researchers say this design was inspired by that of brain cells, which can radiate branches out like a tree, with each branch used to communicate with another brain cell. "All those connections are why the brain is so powerful," Bandyopadhyay said. Since duroquinone possesses four cones, each molecule essentially has four different settings. Since the central molecule can simultaneously control 16 other duroquinones, mathematically this means a single pulse at the machine can have 4^16 — or nearly 4.3 billion — different outcomes. In comparison, a normal computer transistor can only carry out just one instruction at once, and only has two settings — 0 and 1. This means a single pulse at it can only have two different outcomes. The idea is to hook this new gadget up with other molecules — either copies of itself or different compounds other scientists have invented. For instance, researchers have created a host of machines just a molecule or so large over the last decade or two — motors, propellers, switches, elevators, sensors and so on. The new invention might offer a way to control all those other compounds to work as a whole. Indeed, Bandyopadhyay and his colleagues revealed they could hook up eight other such "molecular machines" to their invention, working together as if they were part of a miniature factory. This invention could serve as the controlling element of complex assemblies of molecular machines, Bandyopadhyay suggested. One future application for such assemblies "could be in medical science," he told LiveScience. "Imagine taking assemblies of molecular machines and inserting them into the blood, perhaps if you wanted to destroy a tumor inside the body."
Guedes' model showed planets forming around the star Alpha Centauri B (its sister star, Proxima Centauri, is actually our nearest neighbor) in what is called the "habitable zone," or the region around a star where liquid water can exist on a planet's surface. The model also showed that if such planets do in fact exist, we should be able to see them with a dedicated telescope. "If they exist, we can observe them," Guedes said. Guedes' study has been accepted for publication in the Astrophysical Journal. A likely Candidate Astronomers have for some time pinned the Alpha Centauri system as one that was likely to form planets, said study co-author Gregory Laughlin, a UCSC professor. "I think that there's been a good line of evidence over the past decade or so," Laughlin told SPACE.com. Several factors mark the system, particularly Alpha Centauri B as friendly to planet formation, Laughlin said. The metallicity of Alpha Centauri B (or how much of its matter is made up of elements heavier than hydrogen and helium) is higher than our Sun's, so there would be plenty of heavier-mass material for planets to form from, he said. Also, because the planet would form in a triple star system, the processes that form large Jupiter-mass gas giants, which account for most of the extrasolar planets found so far, would be suppressed. So it would be more likely for the system to produce terrestrial planets. Laughlin also noted that a number of factors make Alpha Centauri B a good candidate for astronomers to actually detect an Earth-sized terrestrial planet. Planet Earth 2007: Top 10 Science Stories 
From the damning climate report by the IPCC to projections of an impending peak in global oil production, 2007 was full of startling findings and prognostications about the blue marble we call home. Here are the stories we think could reverberate most significantly for years to come.
Now the discovery of tiny diamonds in a Western Australian site provides a new timeline for when this process began. Researchers led by Martina Menneken of Westfälische Wilhelms-Universität in Germany found that the diamonds are surrounded by zircon crystals, which were dated between 3.1 billion and 4.3 billion years old. Because many diamonds are formed in the mantle by intense pressure from the heavy crust above, the researchers suspect that some thick crust may have formed extremely early in the planet’s 4.5-billion-year history. Another recent study looked into just how that crust formed. Geochemists Graham Pearson and Stephen Parman of Durham University in England examined bits of metal from the mantle that had been thrust up onto Earth’s surface by plate tectonics for signs that would indicate when the metal had been molten. The duo found that Earth’s interior had melted in large quantities at a few points in time. Parman says these measurements correlate to the ages of previously dated parts of the crust, thus supporting one popular theory that the continental crust came into being in a few distinct bursts.
In a new study, the team finds that a fossilized specimen of the extinct, 48-million-year-old mammal Indohyus bears several telling similarities to whales, including dense limb bones for ballast and a middle ear structure found only in the cetaceans, or sea-dwelling mammals, which is thought to help them hear underwater. "What we think happened is that the ancestors of both Indohyus and whales were animals that looked like a tiny deer," says Hans Thewissen, professor of anatomy at Northeastern Ohio Universities Colleges of Medicine and Pharmacy, who led the study, published in Nature. The modern creature that most resembles Indohyus, however, is the African mousedeer (or chevrotain), which lives on the forest floor but scurries into the water to take cover from predators.
Other experts, however, caution that although the scenario is possible, the ancestry analysis is based on incomplete data. Researchers "really thought the book was closed on this," says Annalisa Berta, an evolutionary biologist at San Diego State University. "To suggest that this fossil somehow is closer than hippos, that's a big deal—I'm just not convinced." Whatever its relationship with whales, Indohyus was probably not a direct predecessor of them, Thewissen says, because the specimen, unearthed 30 years ago in Kashmir, dates to roughly two million years after the earliest known cetacean fossils. The new analysis does not yet unseat the hippo as cetaceans' kissing cousin, because it only takes into account anatomical features, not molecular ones, says Maureen O'Leary, a professor in the department of anatomical sciences at Stony Brook University on Long Island, N.Y. She says that her own categorization of artiodactyls supports the hippo as the closest relative to cetaceans, but notes that it did not include the features uncovered by the Ohio team. Extinctions Linked to Hotter Temperatures
Whenever the world's tropical seas warm several degrees, Earth has experienced mass extinctions over millions of years, according to a first-of-its-kind statistical study of fossil records.
"We found that over the fossil record as a whole, the higher the temperatures have been, the higher the extinctions have been," said University of York ecologist Peter Mayhew, the co-author of the peer-reviewed research published in the Proceedings of the Royal Society B, a British journal. Earth is on track to hit that same level of extinction-connected warming in about 100 years, unless greenhouse gas emissions are curbed, according to top scientists. A second study, to be presented at a scientific convention Sunday, links high carbon dioxide levels, the chief man-made gas responsible for global warming, to past extinctions. In the British study, Mayhew and his colleagues looked at temperatures in 10 million-year chunks because fossil records aren't that precise in time measurements. They then compared those to the number of species, the number of species families, and overall biodiversity. They found more biodiversity with lower temperatures and more species dying with higher temperatures. The researchers examined tropical sea temperatures—the only ones that can be determined from fossil records and go back hundreds of millions of years. They indicate a natural 60 million-year climate cycle that moves from a warmer "greenhouse" to a cooler "icehouse." The Earth is warming from its current colder period. Every time the tropical sea temperatures were about 7 degrees warmer than they are now and stayed that way for millions of enough years, there was a die-off. How fast extinctions happen varies in length. The study linked mass extinctions with higher temperatures, but did not try to establish a cause-and-effect. For example, the most recent mass extinction, the one 65 million years ago that included the die-off of dinosaurs, probably was caused by an asteroid collision as scientists theorize and Mayhew agrees. But extinctions were likely happening anyway as temperatures were increasing, Mayhew said. Massive volcanic activity, which releases large amounts of carbon dioxide, have also been blamed for the dinosaur extinction.
The metamorphosis of a student into a full-fledged scientist takes years, but the Exotic Beam Summer School helps accelerate—so to speak—the process.
There, the students delved into the world of nuclei, the cores of atoms. The journey of nuclei begins at the cyclotron, an accelerator that speeds isotopes to up to half the speed of light. The nuclei flying out of the cyclotron smash into a target made of beryllium, resulting in millions of flying particles per second containing dozens of different isotopes. Many nuclear physicists are interested in rare nuclei because they yield unique information from their perch on the edge of nuclear existence, clues about the structure of these minute particles and hints that reveal secrets about the origins of the elements. Downstream from the cyclotron, a complex system of magnets filters out the few desired nuclei from billions of flying particles. Normally, a team of specialists would perform the intricate tweakings of the knobs and buttons that would sift out the few precious particles. NSCL beam physicist Marc Hausmann estimates that getting the perfect filtering for an experiment takes from 6 to 24 hours. But for this 24-hour period, the summer school students were in full command. "Identifying a particle is like identifying one person in the whole world population," said Giuseppe Lorusso, a third-year NSCL graduate student and summer school participant. In the culmination of all they learned during the week, six groups took turns performing four-hour runs of the beam. This year, simulating the process to a new discovery, students set out to produce phosphorous-35—heavier than the common version of the element—and measure the isotope’s half-life. "What the students would have learned in one semester in a good nuclear physics course is probably what they learned in this one week," said Raman Anantaraman, assistant director of user relation at NSCL and head coordinator of the summer school." "Learning to do research means doing research," says Stolz, an NSCL beam physicist and lecturer at the summer school.. "It’s like learning to swim. You start in shallow water, and then it gets deeper and colder, and by that time you can swim. At the very end you let the sharks in."
You are reading these words right now because 600 million years ago, an aquatic animal called a Hydra developed light-receptive genes—the origin of animal vision.
Scientists at the University of California, Santa Barbara studied the genes associated with vision (called opsins) in these tiny creatures and found opsin proteins all over their bodies. Though they don't have eyes or any specific light-receptive organs, researchers think that the light-sensing proteins concentrated in the mouth area of the Hydras help them to use light sensitivity to search out prey. Because studies of animals that evolved earlier, such as sponges, don't show the same light sensitivity, scientists were able to pinpoint the Precambrian date that animal vision first started to evolve. "We now have a time frame for the evolution of animal light sensitivity," said study leader David Plachetzki, a UC Santa Barbara graduate student. "We know its precursors existed roughly 600 million years ago. These findings, detailed in a recent issue of the online journal PLoS ONE, counter arguments by anti-evolutionists that evolution can only eliminate traits and cannot produce new features, the authors say. “Our paper shows that such claims are simply wrong," said co-author Todd Oakley, also a UC Santa Barbara biologist. "We show very clearly that specific mutational changes in a particular duplicated gene (opsin) allowed the new genes to interact with different proteins in new ways. Today, these different interactions underlie the genetic machinery of vision, which is different in various animal groups.” More Species on Brink of Extinction
More than 16,300 species of animals and plants are on the verge of disappearing from the planet, with nearly 200 more species approaching extinction within the last year, according to the World Conservation Union's 2007 Red List of Threatened Species.
However, scientists say they have no clue how many species truly exist on the planet, as most have yet to be catalogued. Nonetheless, the Red List highlights risks to many visible species, including mammals and other large creatures. “This year’s IUCN Red List shows that the invaluable efforts made so far to protect species are not enough," said Julia Marton-Lefèvre, director general of the World Conservation Union (IUCN). "The rate of biodiversity loss is increasing, and we need to act now to significantly reduce it and stave off this global extinction crisis.” The IUCN says that the total number of recently extinct species has reached 785 this year, with another 65 species found only in captivity or in cultivation. According to the 2007 Red List, one quarter of all mammals, one eighth of all birds and one third of all amphibians are jeopardy. Animals aren't the only species in danger, as 70 percent of the world's plants that have been assessed are at risk of disappearing. Of our closest relatives, gorillas and orangutans are both classified as Critically Endangered (the last step on the list before Extinction status). Gorillas have been decimated by local human conflicts, the commercial bushmeat trade and the Ebola virus, with a 60 percent decline in their populations in the last 25 years. Orangutans are threatened by burning and logging of their forest homes. The Yangtze River Dolphin, reported to be extinct several weeks ago and thought later to have been recently spotted, is listed as Critically Endangered and Possibly Extinct due to habitat destruction from pollution and river traffic. Corals were added to list the list for the first time this year. People are the main reason for most species' decline, whether through direct means such as over-hunting or indirect means such as the introduction of invasive species.
A drastic shift in the tropical African climate many thousands of years ago may have given a significant push to early human evolution, a new study says.
But after that time, the climate stabilized and became wetter, allowing lake levels to rise dramatically. It was around this same time that early human populations in Africa grew rapidly and began to migrate. "The population expansion and subsequent spreading of 'Out of Africa' human colonizers may have been aided by the newly stabilized climate," said study team leader Christopher Scholz of Syracuse University in New York. The team used cores of sediments taken from Africa's Lake Malawi (as part of the National Science Foundation's Lake Malawi Drilling Project) to shed light on past climate changes in the area. Lake Malawi is located on the southern end of East Africa's Rift Valley, between Mozambique, Malawi and Tanzania. The lake cores showed that megadroughts plagued parts of tropical Africa over the last million years, with lake levels sometimes dipping below 15 percent of the current level. But around 70,000 years ago, lake levels rose dramatically. "The sediment cores from Lake Malawi are the longest continuous record of climate change available from the continental tropics," said NSF program director Paul Filmer, who wasn't directly involved with the research. "The link between the signals of East African moisture levels in core samples from the lake and a critical stage in human evolution is an important discovery."
Electrically charged specks of interstellar dust organize into DNA-like double helixes and display properties normally attributed to living systems, such as evolving and reproducing, new computer simulations show. But scientists are hesitant to call the dancing dust particles "alive," and instead say they are just another example of how difficult it is to define life.
The computer model, detailed in the Aug. 14 issue of the New Journal of Physics, shows what happens to microscopic dust particles when they are injected into plasma. Plasma is the fourth state of matter along with solids, liquids and gases. While unfamiliar to most people, plasma is the most common phase of matter in the universe. It's everywhere: Stars are luminous balls of plasma, and diffuse plasma pervades the space between stars. Plasma forms when gas becomes so hot that electrons are stripped from atomic nuclei, leaving behind a soup of charged particles. Past studies on Earth have shown that if enough particles are injected into a low-temperature plasma, they will spontaneously organize into crystal-like structures. The new computer simulations suggest that in the gravity-free environment of space, the plasma particles will bead together to form string-like filaments that then twist into corkscrew shapes. The helical strands resemble DNA and are themselves electrically charged and attracted to one another. The computer-modeled plasma particles can also divide to form two copies of the original structure and even "evolve" into more stable structures that are better able to survive in the plasma. "These complex, self-organized plasma structures exhibit all the necessary properties to qualify them as candidates for inorganic living matter," said study team member V.N. Tsytovich of the Russian Academy of Science. Is It Alive? Nevertheless, Tsytovich's colleague and study team member, Gregor Morfill of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, is hesitant to call the plasma particles alive. "Maybe it's a question of upbringing," Morfill said in a telephone interview. "I would hesitate to call it life. The reason why we published this paper is not because we wanted to suggest this could evolve into life, but because we wanted to start the discussion ... once more of what exactly do we mean by life." Seth Shostak, a senior astronomer at the SETI Institute in Mountain View, California, also was cautious in calling the particles alive. "The facts are, we still don't have a good definition of what 'life' is," Shostak told SPACE.com. Shostak points out that while most high-school biology textbooks include as requirements for life the ability to metabolize and reproduce, it's easy to think of things that break these rules. Fire, for example, reproduces and metabolizes, but most people would not say it is alive; and mules, which are clearly alive, can't reproduce. "We still stumble on what it means to be alive, and that means that these complex molecules are in a never-never land between the living and the merely reacting," Shostak added. If the particles were considered alive though, Shostak said, it would completely overturn another common assumption about life. "We've always assumed that life was a planetary phenomenon. Only on planets would you have the liquids thought necessary for the chemistry of life," he said. "So if you could have life in the hot gases of a star, or in the hot, interstellar gas that suffuses the space between the stars, well, not only would that be 'life as we don't know it' but it might be the most common type of life." Major Planet Formation Mystery Solved
Planet formation is a story with a well-known beginning and end, but how its middle plays out has been an enigma to scientists--until now.
Truckin' Boulders The stuff of rocky planets originates in an accretion disk, or collection of gas and dust that circles around a newborn star. Over time the dust particles bunch together and form large boulders, but eventually they meet "wind" resistance from the disk's mist of gas. "They see a headwind. It's deadly and drags them into the star," Mac Low told SPACE.com. Modeling the turbulence within the gas, however, showed that boulders can team up and form planets. "Turbulence in the disk concentrates boulders in regions of higher pressure," Mac Low said, noting that such a disturbance is enough to enable the boulders to fight the dooming headwind. "If the gas is sped up, the boulders don't see a headwind. By getting the gas going with them they conserve energy and stay in orbit." Mac Low compared the effect to a chain of semi-trucks driving down a highway. Each boulder is like a semi-truck "pushing" the gas in front of it, creating a friendly pocket of air behind it that other semis can travel in without using up as much fuel. "The end of the story is that enough boulders gather together, gravity takes over and they collapse into planet-like bodies," Mac Low said. Mac Low and his colleagues' findings will be detailed in an upcoming issue of the journal Nature. Pulverizing Problem Although Mac Low and his colleagues kept planet-forming boulders safe from the gravitational clutches of stars in their simulation, he noted that many questions remain. "There are enough uncertainties that [planet formation] is not going to be an open and shut case any time soon," he said. "We don't know how that collapse into a planet actually occurs. You've got thousands, millions of boulders swarming together like a bees. In my nightmares I imagine that they grind each other down to dust and it all goes away." Despite the problem, Mac Low is confident the theory will hold up to future scrutiny. "All that material is gravitationally bound together, so we think it's likely that it will form large objects," he said. Running the computer simulation, in fact, formed tight boulder clusters as large as the dwarf planet Ceres (formerly known as the asteroid Ceres). Alan Boss, an astrophysicist with the Carnegie Institution in Washington, D.C., said that the theory is attractive despite the caveat. "Overall, the calculations present an encouraging approach to understanding how something happened that we know must have happened, at least for the terrestrial planets," Boss said in an e-mail. How giant planets form yet another question. One idea is that gas coalesces around a rocky, or terrestrial planet. Boss, however, thinks the gas giants collapse from a knot, much in the manner of star formation. Mac Low and his team plan to address the mystery of how boulders collapse into planetesimals, or protoplanetary chunks of rock, in the future. See Evolution's Biggest Bones of Contention
Human fossils look like a bunch of dusty old bones to most people, but to paleoanthropologists, scholars who piece together our ancient past, they are more beautiful than diamonds.
The crown jewel of these ancient full skeletons is Lucy, a woman found in the barren Afar region of Ethiopia in 1974 by Donald Johanson and his team. Officially called an Australopithecus afarensis, Lucy lived 3.2 million years ago, was three and a half feet tall (rather short for her kind) and walked like we do. But she had a brain the size of a chimpanzee and probably spent time swinging through the trees as her curved hand bones indicate. Lucy is the quintessential combination of human and ape, and she changed the way we draw the path of human evolution. And now Lucy is coming to a museum near you. The Ethiopian government is sending a major show of fossils on tour around the United States, with Lucy as the star. She will land in Houston, Texas, and then hit 10 other cities over several years. The announcement of this tour has sparked controversy in the museum and academic communities. Some feel Lucy is too fragile to travel. Others feel she is too sacred to be on display. But the nay-sayers tend to be scientists who've had a good look at her anyway. For the rest of us, this is a chance of a lifetime, more significant than viewing King Tut's mask, and more amazing than the Hope Diamond. In fact, a viewing of Lucy will spark public interest in human evolution, and that's good for everybody, scientists and the general public alike. Truth is, this is not the first time important human fossils have come to the United States. In 1984, the American Museum of Natural History gathered original human fossils from all over the world for their "Ancestors" exhibition. For those with an interest or obsession with the human past, getting a look at the real stuff was a profound experience. But Lucy was not in attendance. Her current tour is our chance to see the little woman who changed human history. I, for one, will be happy to stand in line.
Geologists have discovered 1.43 billion-year-old fossils of deep-sea microbes, providing more evidence that life may have originated on the bottom of the ocean.
Kusky said that the fossils offer "tantalizing suggestions" that life developed near deep-sea hydrothermal vents and not in shallow seas, as other evidence hints. Black smoker chimneys develop at submerged openings in the Earth's crust that spew out mineral-rich water as hot as 752 degrees Fahrenheit (400 degrees Celsius). Bacteria that don't depend on sunlight or oxygen move into the fragile chimneys that grow around the vents and feed on the dissolved minerals. "Some people like to call it life in extreme environments. These bacteria pretty much live on a different planet compared to conditions we live in," Kusky told LiveScience. The stony chimneys can grow more 50 feet (15 meters) tall, but retrieving even a modern chimney sample is extremely difficult, as they're fragile and can crumble when touched. "This discovery offers scientists valuable on-land samples for geological and geo-biological research," Kusky said, noting that some of the fossils he unearthed measure a whopping 3 feet in length. The age and size of the chimneys, Kusky said, will help scientists understand how ancient hydrothermal vent growth and the development of life on the sea floor might be interconnected. Although the fossils may be old, they aren't the oldest evidence of life on Earth. The most ancient specimens are 3.5 billion-year-old, dome-shaped clumps of bacteria called stromatolites, which were found in western Australia and suggest that shallow seas were the birthplace of life. Ed Mathez, a geologist and curator at the American Museum of Natural History in New York who is not connected to the discovery, said even with stromatolites the verdict on life's origin is out. "They tell us life existed that long ago, but as to where it originated remains an open question," Mathez said. Mathez pointed out that black smoker fossils are just as inconclusive about the origin of life , but added that the new finding significantly pushes back the known reign of deep-sea microbes. "Personally, a deep-sea origin of life strikes me as a very good possibility," he said. In the end, Kusky said, there may yet be even older black smoker chimney fossils waiting to be discovered. "So far, these fossils provide oldest evidence for deep-sea life," he said. His team's findings are detailed in the current issue of the journal Gondwana Research.
A 400 million-year-old fossilized fin from a strange-looking, primitive fish is shedding light on how fins evolved into limbs that enabled animals to walk on land.
Surprisingly, however, the patterns don't match the lobe-finned fish's living relative. Until now, scientists had assumed the living coelacanths and their relatives, the lungfish, served as accurate models of their ancestors dating back hundreds of millions of years ago. "Two living fossils, coelacanths and lungfishes, are in fact not primitive," said lead author Matt Friedman of the University of Chicago. "They are specialized, and they are not particularly good models for understanding the origin of limbs." In fact, living coelacanths are adapted for deep-water habitats off the coasts of Africa and Indonesia where they use a specialized organ in their noses to detect weak electrical signals from prey hidden in the mud along the seafloor. Unlike fins on living coelacanths and lungfishes, the fossil fin has an asymmetrical pattern in which there are more bones on the front of the central shaft than the back. It has more in common with the anatomy of four-limbed vertebrates, called tetrapods, and even humans than it does with the anatomy of living coelacanths. The discovery of the new fossil means scientists can no longer make inferences about the evolution of limbs based on living coelacanths and lungfishes. “To understand the developmental evolution of the limbs of tetrapods, we shouldn’t be looking at the fins of our nearest living fish relatives—lungfishes and coelacanths—because they’re far too specialized,” said co-author Michael Coates, a University of Chicago biologist.
Like a secret ingredient to a signature recipe, "survival of the fittest" is a crucial part of the theory of evolution. The fittest individuals survive to mate and pass on their genetic lineage, and the weaker creatures fail to pass on their wimpy genes.
Running about 100,000 times faster than a high-end desktop PC, IBM has unveiled the world’s fastest computer. Already, it's not fast enough.
 The varying sizes of S Orionis compared to the inner Solar System. The red giant pulsates from the yellow disk out to the inner red disk. In 5 billion years the Sun will evolve to this stage before cooling down as a white dwarf. All the distances are to scale, while the diameters of the Sun, planets and maser spots (in red and green) are not. Using the largest telescopes available, astronomers have dissected the dusty, gassy layers of the red giant S Orionis--a star that pulsates in size from a diameter roughly equal to the orbit of Mars to halfway between Mars and Jupiter every 410 days. The information provides a glimpse at the future of our own sun, which will puff into a red giant like S Orionis in about 5 billion years, said astronomer David Boboltz of the U.S. Naval Observatory. "No study of a red giant has been done to this level, looking at infrared and radio-wave views simultaneously," Boboltz said. "This really show us where the layers are." Red giants are older versions of the sun that, once they have burned off most of their hydrogen fuel, begin to burn helium. This creates intense "flashes" of radiation that puff the star up to more than 100 times its original size as it pushes stellar gas and dust out into space. S Orionis sheds about the mass of Earth each year. "A lot of material escapes from the star's gravity, and begins to form beautiful planetary nebulas," Boboltz said. "But gravity overcomes a lot of gas and dust that gets pulled back into the star, starting the cycle all over again and forming a kind of pulse." Where those layers are located and exactly what they're made of, however, was a mystery until Boboltz and his colleagues' investigation, which is detailed in a July issue of the journal Astronomy & Astrophysics. The team measured the shells of gas and dust surrounding the star to most detailed level to date, discovering that the star's dusty shell of corundum--a compound used in sandpaper--was twice as large as previously thought. They also showed dusty corundum mixing heavily with gaseous silicon monoxide, a compound astrophysicists thought existed as a dust outside of red giants. "We've essentially mapped the envelopes of material around these stars, which has never really been done before," Boboltz said. Big investigation The researchers aimed two of Earth's biggest interferometer telescopes at the star to peer at its layers: the Very Long Baseline Array (VLBA), a series of 10 telescopes spread over 5,350 miles that can see radio waves, and the infrared-seeing Very Large Telescope Interferometer (VLTI) in Chile.If the telescopes were in New York, Boboltz noted, they would allow someone to read a newspaper in California. But regular sources of radio and infrared waves would make S Orionis look more like "a blob of emissions," so his team recorded its "masers," or naturally occurring lasers. Astrophysicists aren't entirely sure how they form, but the basic principles of a laser apply: Some process evenly energizes one kind of molecule to produce a "synchronized" wave of light. "Stuff like corundum and silicon monoxide, which we detected in S Orionis, emit their own unique masers," Boboltz said. By watching the masers move over the period of a few months, they recorded an extremely detailed picture of the red giant's pulsating behavior. A video exists of another pulsating red giant star, call TX Cam, but Boboltz expects to surpass it's a visualization of only radio images."Soon we'll be able to create even better views of the pulsating cocoon around S Orionis by looking at water masers," Boboltz said, which exist at the farthest reaches of the cocoon. "We also hope to explain how a planetary nebula forms from a red giant near the end of its life as a white dwarf star."
Bone-crushing wolves that specialized in hunting giant prey once roamed the icy expanses of Alaska, an international team of researchers now finds.
HATOYAMA, Japan (AP) -- Forget the clicker: A new technology in Japan could let you control electronic devices without lifting a finger simply by reading brain activity.
Tracks Reveal Dinosaurs Swam
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With the price of oil climbing and the world's heavy dependency on this fossil fuel, estimates of just how much oil we have left are critical knowledge for governments and policy makers. A new study this year predicted that global oil production could peak as soon as 2008, and would likely do so before 2018.
Earth's southernmost continent yielded a host of surprises this year. Satellite lasers detected a series of previously unknown subglacial lakes under the Antarctic ice, which drain and fill very rapidly and could shed light on how water below the surface moves ice streams above.
While a severe drought brought parts of the Southeast to its knees for several months this fall, those living in the Southwest (which has been in drought for years, if you buy the new definition of drought) may have a more extended drought to contend with... for the next 90 years.
Despite some good news for endangered animals, such as the discovery of a massive wildlife migration across previously war-torn southern Sudan, animals are becoming increasingly under threat by deforestation and other forms of habitat destruction, pollution and poaching.
Between warming seas, pollution and overfishing, coral reefs have had it rough in recent years, and this year was no exception. Scientists at San Diego State University found that when humans and reefs are neighbors, reefs just can't compete and become susceptible to diseases, particularly herpes viruses. Corals don't just get cold sores, however. They die.
Despite the dire predictions of scientists of the effects of continuing to emit carbon dioxide and other greenhouse gases, one study this year found that emission rates are actually accelerating because of the rising amount of the gas needed to produce one unit of wealth and the declining efficient of Earth's natural carbon sinks. Other studies showed how much carbon dioxide these sinks were taking up, with drought reducing the amount of carbon dioxide that plants take up, but forest growth increasing the amount that trees siphon out of the atmosphere.
Natural gas came a step closer to being used in everyday cars with the development of a new storage tank that makes the fuel source a better option for more compact vehicles. Ethanol had a roller coaster year with some research improving its possible use–one team developed earless corn that could be a better source of the biofuel and other researchers used cow stomach fluid to better break down the raw material for use in a fuel cell. But other scientists called into question the advisability of using ethanol as a fuel source because it may take more energy to produce than it provides and may be more harmful than gasoline.
Several studies this year pointed out that our addition of increasing amounts of carbon dioxide into the atmosphere are prodding Earth's climates to varying extremes. One study found that more hurricanes are forming now than a century ago, threatening the millions of people that live along the world's coastlines, though some argue that this may not be the case because old storm records could be incomplete–Victorians didn't have satellites after all.
This was a bad year for polar bears too, as summer ice melt reached a record extent in the Arctic. (Greenland too saw a record level of melt, enough to cover twice the area of the United States.) While the melt was a boon to marine vessels, opening up the fabled Northwest Passage, it could spell trouble for the polar environment, and the globe, if it keeps up each year.
The Intergovernmental Panel on Climate Change issued its fourth report this year and its strongest statement yet that human activities are a prime cause of global warming. The scientists who wrote the report warned of the potentially catastrophic and unstoppable changes that could occur if emissions of greenhouse gases such as carbon dioxide are not curbed, including droughts, sea level rise, more severe weather, melting of glaciers and polar ice and floods.
But if that's how it works, where do all the runts in nature come from? A new study of red deer populations, detailed in a recent issue of the journal Nature, suggests that a genetic tug-of-war related to sex may be responsible. When red deer search for mates , each sex instinctively looks for different qualities. Males seek out females that will produce the biggest, toughest sons, and females seek males that carry a genetic blueprint for the best offspring-creating daughters.
The new king of the supercomputers is the IBM Blue Gene/P running at a speed of at least one petaflop per second, meaning it can solve one quadrillion floating point math problems per second.
(A quadrillion is a million billions, or 1 followed by 15 zeroes.A “floating point operation” means an arithmetic problem involving two numbers with decimal points, such a 2.5 X 3.14159.)
The scientists unexpectedly discovered what apparently was a novel subspecies of gray wolf (Canis lupus) as they analyzed genes from skeletal remains that had sat in museum collections for up to a few decades after excavation from Alaskan permafrost deposits. The ancient DNA, which dated back 12,500 to 40,000 years, did not match any modern wolves, and closer investigation of the bones uncovered remarkable differences.
These extinct predators had strong jaws and massive teeth, ideal for killing and devouring mammoths and other megafauna.
The “brain-machine interface'' developed by Hitachi Inc. analyzes slight changes in the brain's blood flow and translates brain motion into electric signals.
A cap connects by optical fibers to a mapping device, which links, in turn, to a toy train set via a control computer and motor during one recent demonstration at Hitachi's Advanced Research Laboratory in Hatoyama, just outside Tokyo.
Since 1991, planetary scientists have floated the idea that Mars once harbored vast oceans that covered roughly one-third of the planet. Two long shore-like lips of rock in the planet's northern hemisphere were thought to be the best evidence, but experts argued that they were too "hilly" to describe the smooth edges of ancient oceans.
HOUSTON - The Nobel Prize-winning scientist who helped discover the molecular structure of DNA has become the first person to receive his own personal genome map.
OSLO - Human activities are wiping out three animal or plant species every hour and the world must do more to slow the worst spate of extinctions since the dinosaurs by 2010, the United Nations said on Tuesday.
Newly discovered fossilized claw marks are painting a picture of a carnivorous dinosaur pedaling its hind legs as it swam against a strong current and struggled to maintain a straight path.
Engineers are tinkering with a new-age engine that could reduce fuel consumption and in turn help to squelch greenhouse gas emissions associated with automobiles.