Scientific American

[The following is an exact transcript of this podcast.]

Olive oil producers generally guess the best time to harvest their olives by [More]

If you take scientists at their word, human-induced climate change is well underway, evolution accounts for the diversity of life on Earth and vaccines do not cause autism. But the collective expertise of thousands of researchers barely registers with global warming skeptics, creationist movie producers and distrustful parents. Why is scientific authority under fire from so many corners? Sociologist Harry Collins thinks part of the answer lies in a misunderstanding of expertise itself. Like Jane Goodall living among the chimps, Collins, a professor at Cardiff University in Wales, has spent 30 years observing physicists who study gravitational wave detection--the search for faint ripples in the fabric of spacetime. He's learned the hard way about the work that goes into acquiring specialized scientific knowledge. In a recent book, Rethinking Expertise, he says that what bridges the gap--and what keeps science working--is something called "interactional expertise". Collins spoke recently with ScientificAmerican.com about his view of expertise; what follows is an edited transcript of that interview.

How did we get to the point where scientific authority is so easily challenged? [More]

Felled mangrove trees may have doomed the coast of Myanmar [More]

A company banking on drivers' weariness of skyrocketing gasoline prices unveiled a home refinery device on Thursday offering another option: ethanol. E-Fuel Corporation says its EFuel100 MicroFueler can produce up to 35 gallons (132 liters) of ethanol a week that consumers can pump directly into their cars and trucks. There is no combustion inside the device, which runs on a standard household 110- to 220-volt AC power supply (consuming about 150 watts per day) and uses a membrane system to distill the sugar, yeast and water solution required to make ethanol rather than combustion heating elements, as commercial ethanol producers do. [More]

In a finding that may help scientists better predict the pace of climate change, research published in Science shows how the Sahara Desert, a region as big as the U.S. that stretches from the Atlantic Ocean to the Red Sea across northern Africa, went from bountiful to bone-dry over a period of several thousand years.

Scientists peered into the Sahara's verdant past by analyzing sediment samples drilled out of the bottom of one of the desert's last living lakes. The samples revealed long-held secrets of how desert-friendly species replaced tropical plants and animals as monsoon rains retreated farther south into the continent.

Fluoride FindingsA report by the National Research Council (NRC) is cited as suggesting negative effects of fluoride in “Second Thoughts about Fluoride,” by Dan Fagin. But the NRC notes that its report was not initiated because of concerns about the low levels of fluoride used in community water fluoridation, nor did it examine that issue. Instead the report is part of a routine review by the Environmental Protection Agency to address whether the higher levels of naturally occurring fluoride currently allowed in drinking water pose a health risk. The EPA is evaluating the report.

Editor's Note: Stuart Kauffman has a well-earned reputation as a scientific provocateur, albeit one with the weight of data and wisdom on his side. Kauffman, a complexity researcher and biologist of the University of Calgary and the Santa Fe Institute, has argued, for example, that self-organization--the propensity for systems to become more complex without outside guidance--was just as important as natural selection in shaping evolution. (Intelligent design advocates, take note.)

In his new book Reinventing the Sacred: A New View of Science, Reason, and Religion (Basic Books, New York; May 2008), Kauffman develops a larger argument: Understanding what's happening in complex systems could help modern science break free of what some consider its too-reductionistic underpinnings. One controversial idea that Kauffman develops in his book is that by failing to take this approach to economics, traditional economists are unable to explain something that seems obvious but isn't: How does innovation drive growth?

[The following is an exact transcript of this podcast.]

Would America be a better place if more people with science training held elective office?  One organization that thinks so is Scientists and Engineers for America, or SEA.  On May 10th, they’re holding a daylong workshop in Washington, D.C., to teach researchers the nuts and bolts of running for office.  More than 70 attendees have signed up. [More]

Lawmakers yesterday introduced legislation designed to speed the development of new, safer therapies for brain and nervous system disorders and injuries, which affect an estimated 100 million Americans and costs an estimated $1.3 trillion annually to treat. [More]

Like a team of laboratory gearheads, Arizona State University (A.S.U.) researchers have found a way to soup up microscopic "nanomachines" that may someday be used to deliver lifesaving medications or test the quality of drinking water in remote regions of the world. In place of turbochargers and high-octane gas, the scientists tweaked their engine design and used an additive to speed the oxidation of hydrogen peroxide into fuel to create nanomachines 350 times more powerful than any previously built. [More]

A new more secure technology for guarding against theft from nuclear reactors has passed its first test.

Researchers from Lawrence Livermore National Laboratory and Sandia National Laboratories in Livermore, Calif., successfully monitored the power output of a relatively small nuclear power reactor by measuring the number of antineutrinos--ghostly particles generated by nuclear fission--that struck a refrigerator-size tank of liquid.

The platypus (Ornithorhynchus anatinus) is an odd-looking creature whose features combine the furry torso and wide, flat tail of a beaver with the rubbery bill and webbed feet of a duck. But its looks are not all that is strange about it. A new study indicates that the distinctive mammal's genetic code is an eclectic brew of bird, reptile and mammal. [More]

Mystery Cruise ControlThe velocities of Pioneer 10 and 11, now speeding out of the solar system, are mysteriously changing, as if an extra force from the sun were tugging at them. Explanations have ranged from gas leaks and observational error to modified theories of gravity [see “A Force to Reckon With”; SciAm, October 2005].

One of the first things U.S. Rep. Steve Kagen (D–Wisc.) did when he took office last year was to nix his congressional health care coverage. The move stunned a human resources staffer, who, the lawmaker says, looked at him as though he were insane.

"I'll respectfully decline until you can make that same offer for all of my constituents," he says he told her, explaining his decision to turn down what many say is the Cadillac of U.S. health plans.

Podcast Transcript: It sounds like something out of a bad science fiction novel. During World War II, a fungus called Tricoderma reesei ate its way through US military uniforms and tents in the South Pacific. It chewed up the cloth and used special enzymes to convert the indigestible cellulose into simple sugars. Now that infamous fungus is getting some good publicity. It looks like it might hold a key to improving the production of biofuels.  [More]

Japan was rocked by a series of earthquakes today about 100 miles (160 kilometers) from Tokyo that injured two, cut off power to some 2,100 homes, and left the country on high alert for possible aftershocks. The largest quake hit at 1:45 a.m. local time in the Pacific Ocean off the coast of the Ibaraki Prefecture and measured 6.8 on the Richter scale, but Japan's meteorological agency told the Agence France-Presse (AFP) that it does not expect the tremors to result in a tsunami. [More]

David Kohn, curator of the Darwin's Garden exhibit at the New York Botanical Garden, discusses Darwin's botanical studies. And Harvard Medical School's Jack Szostak talks about research into the origins of life. Plus we'll test your knowledge of some recent science in the news. Websites mentioned on this episode include www.nybg.org/darwin; www.hhmi.org; www.sciam.com/daily

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For $1,000 and up, several new companies will scan an individual’s entire genome for clues about ancestry, potential health limitations and the inheritance of traits such as lactose intolerance. Clients can compare their DNA with a celebrity’s or invite friends and family members to share genetic profiles. Despite the comprehensive reports and background data these Web-based services deliver, some observers believe the information is more recreational than relevant.

Direct-to-consumer genetic tests have existed for at least a decade, and in recent years the number of choices has exploded. Whereas most of these offerings probe for only a small number of gene variants, advances in genome chips now allow a quick, inexpensive search for a wide range of targets all at once. Navigenics in Redwood Shores, Calif., 23andMe in Mountain View, Calif., and deCODE Genetics in Reykjavik, Iceland, recently began scanning for markers associated with as many as two dozen conditions and traits. And for upward of $350,000, Knome in Cambridge, Mass., enables customers to join J. Craig Venter and James D. Watson in the elite cadre of humans who have had their entire genome sequenced, analyzed and interpreted.