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Science

Why Birds Fly In a V Formation 207

sciencehabit writes "Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study of ibises — where researchers took to microlight planes and recorded birds strapped with GPS in-flight — finds that these big-winged birds carefully position their wingtips and sync their flapping, presumably to catch the preceding bird's updraft and save energy during flight."
Biotech

DNA Detectives Count Thousands of Fish Using a Glass of Water 61

vinces99 writes "A mere glass full of water from Monterey Bay Aquarium's 1.2 million-gallon Open Sea tank is all scientists really needed to identify the Pacific Bluefin tuna, dolphinfish and most of the other 13,000 fish swimming there. Researchers also discerned which of the species were most plentiful in the tank. Being able to determine the relative abundance of fish species in a body of water is the next step in possibly using modern DNA identification techniques to census fish in the open ocean, according to Ryan Kelly, University of Washington assistant professor of marine and environmental affairs, and lead author of a paper in the Jan. 15 issue of PLOS ONE. 'It might be unpleasant to think about when going for a swim in the ocean, but the water is a soup of cells shed by what lives there,' Kelly said. Fish shed cells from their skin, damaged tissues and as body wastes. 'Every one of those cells has DNA and if you have the right tools you can tell what species the cell came from. Now we're working to find the relative abundance of each species present,' he said."
Technology

Carbon Nanotubes and Spongy Polymer Help Transistors Stretch 17

MTorrice writes "To make future displays that roll, bend, and stretch, electronics makers need the circuits that control the pixels to be elastic. In particular, they need flexible transistors. Now researchers have combined a carbon nanotube mesh with a spongy ionic polymer to build super-stretchy transistors. The scientists can pull the devices to lengths 57% greater than their resting length without disrupting performance."
Stats

Why Standard Deviation Should Be Retired From Scientific Use 312

An anonymous reader writes "Statistician and author Nassim Taleb has a suggestion for scientific researchers: stop trying to use standard deviations in your work. He says it's misunderstood more often than not, and also not the best tool for its purpose. Taleb thinks researchers should use mean deviation instead. 'It is all due to a historical accident: in 1893, the great Karl Pearson introduced the term "standard deviation" for what had been known as "root mean square error." The confusion started then: people thought it meant mean deviation. The idea stuck: every time a newspaper has attempted to clarify the concept of market "volatility", it defined it verbally as mean deviation yet produced the numerical measure of the (higher) standard deviation. But it is not just journalists who fall for the mistake: I recall seeing official documents from the department of commerce and the Federal Reserve partaking of the conflation, even regulators in statements on market volatility. What is worse, Goldstein and I found that a high number of data scientists (many with PhDs) also get confused in real life.'"
Space

Rare Exoplanet Found In Star Cluster, Orbits Sun's 'Twin' 63

astroengine writes "Three new exoplanets have been discovered inside a star cluster, which is a rare find as only a handful of such exoplanets are known to exist. However, one of the three new finds is even more remarkable — it orbits a star that appears to be 'an almost perfect solar twin.' The discovery was made by astronomers using the European Southern Observatory's HARPS exoplanet-hunting instrument (PDF) attached to the 3.6-meter telescope at the La Silla Observatory in Chile and was confirmed by other collaborating observatories. The astronomers' attention was focused on the Messier 67 open star cluster, which is located approximately 2,600 light-years away in the constellation Cancer."
Government

U.S. Science Agencies Get Some Relief In 2014 Budget 83

sciencehabit writes "The ghost of former President George W. Bush permeates the 2014 budget that Congress released this week. His presence is good news for physical scientists, but less cheery for biomedical researchers, as Congress reserved some of the biggest spending increases for NASA and the Department of Energy. The National Institutes of Health, meanwhile, got a $1 billion increase that is drawing mixed reviews from research advocates."
Science

Why Transitivity Violations Can Be Rational 169

ananyo writes "Organisms, including humans, are often assumed to be hard-wired by evolution to try to make optimal decisions, to the best of their knowledge. Ranking choices consistently — for example, in selecting food sources — would seem to be one aspect of such rationality. If A is preferred over B, and B over C, then surely A should be selected when the options are just A and C? This seemingly logical ordering of preferences is called transitivity. Furthermore, if A is preferred when both B and C are available, then A should 'rationally' remain the first choice when only A and B are at hand ... But sometimes animals do not display such logic. For example, honeybees and gray jays have been seen to violate the Independence of Irrational Alternatives, and so have hummingbirds ... Researchers have now used a theoretical model to show that, in fact, violations of transitivity can sometimes be the best choice (original paper) for the given situation, and therefore rational. The key is that the various choices might appear or disappear in the future. Then the decision becomes more complicated than a simple, fixed ranking of preferences. So while these choices look irrational, they aren't necessarily."

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