Random Samples

Science  08 Feb 2008:
Vol. 319, Issue 5864, pp. 705


    In 1967, psychologist Paul Ekman visited New Guinea to test the idea proposed by Charles Darwin a century earlier that human facial expressions are universal. Last month, the Exploratorium science museum in San Francisco, California, celebrated the 40th anniversary of his trip. The museum's new Mind exhibit displays some of Ekman's photos for the first time, including this montage of indigenous South Fore men. Ekman asked each to show how he would look if he (from left) learned that his child had died, met friends for the first time that day, saw a dead pig in the road, or was about to fight with someone. Anthropologists now agree, says Ekman, that such expressions are biologically determined, as Darwin had thought.


    French scientists are reacting with growing fury to plans by President Nicolas Sarkozy to overhaul basic research.

    In a 21 January speech paying homage to France's 2007 physics Nobelist Albert Fert, Sarkozy lashed out at the research system as plagued by “balkanization” and threatened by “paralysis.” He said major agencies such as CNRS should be turned into “funding bodies rather than performers of research” to “implement science policy specified by the government.” The government may also go ahead with a controversial plan to replace open-ended job commitments for scientists with 4-year contracts.

    Some scientists are livid. Sarkozy wants to “implement rapidly a new stage in demolishing our [basic research] system,” said chemist Henri-Edouard Audier, a board member in the leading researchers' union. The president's attack “thoroughly blackens the situation to show that everything is so rotten that it must be destroyed,” Audier added.

    Physicist Bertrand Monthubert, president of the Let's Save Research movement, said protest plans are being laid. The last time researchers took to the streets was in 2004, to protest budget cuts.


    The male Anna's hummingbird emits an emphatic squeak as he swoops above his intended mates, but it's his tail, not his voice, that makes the sound. A study published online 29 January in the Proceedings of the Royal Society B settles a 68-year-old debate about the source of the chirp.


    Ornithologist Christopher Clark of the University of California, Berkeley, suspected that the sound had something to do with the birds' unusually shaped outer tail feathers. So his team took high-speed videos of the birds doing dive displays in a California park. The videos revealed that a quick tail flick coincided with the squeak, and the displays of four consistent chirpers were silenced when researchers trimmed their tails.

    In the lab, the researchers found that isolated feathers produced a continuous whine when subjected to an air stream. They fluttered like little flags, generating the same frequency regardless of wind speed. “We were blown away,” Clark says, when they realized that the feathers worked like musical reeds, a mechanism previously unknown in birds.

    The study “fully solves” the question of the Anna's chirp and is likely to explain other non-vocal bird sounds as well, says biomechanist Douglas Altshuler of the University of California, Riverside. What's more, the tail sound is nearly identical to part of the birds' vocal song. It's “very wild,” Altshuler says, that the birds evolved to make the same sound in two completely different ways.


    Plan for the Square Kilometer Array—just multiply by 10,000.CREDIT: SKA PROJECT OFFICE AND XILOSTUDIOS

    Skeptics of string theory complain that the purported “theory of everything” is so complicated and flexible that it's impossible to test experimentally. But theoretical cosmologists Rishi Khatri and Benjamin Wandelt, both of the University of Illinois, Urbana-Champaign, claim they've devised such a test.

    According to string theory, every fundamental particle is really a wriggling filament stretching less than a billionth of a billionth of the width of a proton. In some models, space is riven with long cosmic strings, defects in spacetime that affect the distribution of matter. Detectable evidence for them should show up in the mottled distribution of hydrogen gas in the early universe, Khatri and Wandelt calculate in a paper to be published in Physical Review Letters. All you need to see it is an array of radio telescopes covering 10,000 square kilometers.

    A practical proposal? “Nobody would be able to build a 10,000-square-kilometer array,” chuckles Yervant Terzian, a radio astronomer at Cornell University. Terzian is a member of a team proposing to build a 1-square-kilometer array, and that alone will cost more than $2 billion, he says.

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