Random Samples

Science  18 Feb 2005:
Vol. 307, Issue 5712, pp. 1040

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  1. North America's Anatomy


    Twenty-five years in the making, a new geologic map of North America was unveiled this month by the Geological Society of America. The map replaces a 1965 version that predated the widespread acceptance of plate tectonics. “It shows the grand architecture of the continent,” says John Reed of the U.S. Geological Survey in Denver, Colorado, who helped compile it.

    The map covers 15% of Earth's surface and incorporates a vast amount of information from radiometric dating, geologic mapping, ocean cores, and geophysical surveys. It includes more than 900 kinds of rock formations—seven times as many as its predecessor —and many other features such as faults, volcanoes, and impact craters. Some of the biggest scientific advances reflected in the new map concern the Canadian Shield, a vast expanse of ancient rock that underlies most of the continent. The map shows how the shield was assembled from many colliding continents. Alaska (above) has a similar history.

  2. Preserving New Zealand's Bats


    Conservationists in New Zealand are hoping to engineer what they say will be the world's first successful transfer of bats to a new home. Bats are the country's only native land mammals. In the absence of other mammals, one species in particular, the lesser short-tailed bat, has evolved the habit of crawling around on the forest floor in search of food. This has made the species extremely vulnerable to introduced predators such as stoats, cats, and rats.

    Now 20 juvenile bats from a unique population of fewer than 300 living precariously in a North Island forest are this month being taken to Kapiti Island, 5 kilometers off the west coast. Over decades, officials have used shooting, trapping, and poisoning to rid the 2000-hectare sanctuary of introduced mammals from goats to rats. The island is already home to five transplanted endangered bird species.

    The bats resisted a past attempt at transfer. They have a strong homing instinct and can fly long distances, says Brian Lloyd, a conservation biologist with the Department of Conservation in Wellington. To circumvent this problem, officials are transferring newly fledged bats born in captivity in the hope that they will be persuaded to imprint on roost boxes awaiting them on Kapiti. If the transfer is successful, Lloyd says more young bats will be brought to the island over the next 4 to 5 years.

  3. Sumatran Quake Supersized

    Seismologists tracing Earth's shivers in the hours after the great tsunami of 26 December (Science, 14 January, p. 201) have found that they had overlooked fully two-thirds of the energy released.

    By studying bell-like vibrations with periods up to almost an hour long, Seth Stein and Emile Okal of Northwestern University in Evanston, Illinois, discovered that the northern two-thirds of the 1600-kilometer-long fault that runs along the eastern side of the Indian Ocean and the Bay of Bengal must have ruptured slowly. That part of the rupture would have escaped detection when shorter-period waves were used to calculate a conventional magnitude of 9.0. Now the quake looks to have been three times as large, or magnitude 9.3.

    The northward extension of the rupture —which meant a powerful tsunami would be directed at Sri Lanka—helps explain the extreme destruction, according to the researchers. The underestimate argues even more strongly for a tsunami-detecting network, scientists say.

    Indeed, as far away as Washington state, where another offshore subduction zone spells vulnerability to underwater earthquakes, officials are plotting tsunami evacuation routes. Coastal cores show that tsunamis occur there every 500 years or so, the latest one having been 300 years ago.

  4. Signals From Rubble


    Latching onto a cell phone signal from someone trapped in the debris of a building that has just been bombed is no easy task. So engineers are wiring up buildings slated for demolition to track just how radio waves move through rubble.

    Last year electrical engineers Chris Holloway and Kate Remley, who work at the National Institute of Standards and Technology in Boulder, Colorado, set up radio transmitters in Veterans Stadium in Philadelphia, Pennsylvania, just before it was demolished. Then in December, they did the same with Washington, D.C.'s old Convention Center before it was imploded. Early findings suggest that metal debris can boost a signal buried by a pile of wreckage. And with the help of noise-filtering techniques similar to those developed for deep-space communication, it was possible to pick up a simple preprogrammed Morse code message issuing from a transmitter in the rubble of the Convention Center, says Remley.

    The work could improve urban radio networks designed for use after a terrorist attack and offer new strategies for finding faint radio or cell phone signals during an emergency, Remley adds. The next stage of the work is to study how modified hand-held radios could act as beacons after a collapse, perhaps by being designed to switch to a slow signal on a narrow wavelength.

  5. Jobs


    IRRI head. The International Rice Research Institute (IRRI) in Los Baños, the Philippines, has tapped one of its alumni to serve as its next director general. Robert Zeigler, an American plant pathologist who led research programs at the institute from 1992 to 1998, succeeds Ronald Cantrell, who retired in December.

    The 54-year-old Zeigler earned his Ph.D. from Cornell University and has spent most of his career working on the challenges of developing-country agriculture. In addition to his stint at IRRI, he has worked at the International Center for Tropical Agriculture in Colombia, the Institut des Sciences Agronomique du Burundi in Burundi, and the International Maize and Wheat Improvement Center (CIMMYT) in Mexico.

    Zeigler takes over the 45-year-old institute at a time when its donors—governments, agencies, and foundations—have been cutting support. “Maybe I'm a hopeless optimist, but I believe that if we demonstrate we can effectively apply science to real-world needs, we can reinvigorate donor interest in our activities,” he says.

  6. Awards

    Arsenic challenge. The National Academy of Engineering (NAE) is offering a $1 million award to researchers who develop practical, inexpensive technologies for safe drinking water in arsenic-contaminated areas. The Grainger Challenge Prize for Sustainability, funded by the Grainger Foundation, will honor a household or community-scale water treatment system that removes arsenic from groundwater in Bangladesh, India, Nepal, and other developing countries. The winner(s) will be announced in February 2007. Details are at http://www.graingerchallenge.org/ A list of 74 new members and 10 foreign associates, elected by the academy last week, is at http://www.nau.edu./

    Chemistry prize. Stanford University's Richard Zare has won the $100,000 Wolf Prize in Chemistry. Zare, a chemical physicist, receives the award for applying laser techniques to the study of chemical reactions at the molecular level.

  7. Data Point

    Faster entry. A year after receiving a congressional rap on the knuckles, the U.S. State Department says it has significantly reduced processing time for granting visas to students working on sensitive technologies. The extensive security check, called Visas Mantis, now takes less than 2 weeks, on average—a sharp drop from 67 days in mid-2003 (Science, 5 March 2004, p. 1453).

  8. Pioneers


    Mind's eye. Blind since the age of 7, Victor Wong faces a unique challenge as a graduate student at Cornell University: reading color-scaled maps for his research on space weather. Braille cannot address the problem, so he has developed a computer program to translate different colors on a map into distinct piano notes.

    When Wong moves a stylus across the screen, the software speaks out the coordinates and generates notes for color codes representing parameters such as electron density. The sounds help provide a sense of what the data look like “when viewed visually,” he says.

    Wong, who developed the tool in collaboration with fellow student Ankur Moitra (far left) and research associate James Ferwerda, says the next step is telling the user when the stylus has crossed over from land to sea.

  9. They Said It

    “On average, students in grade 6 in this country spend less than 16 minutes per day on science. … I'm glad that my grandsons have a scientist as a grandmother, because I can supplement that easily.”

    —Biologist and University of California Provost M. R. C. Greenwood, speaking last week in Washington, D.C., on the need to improve K-12 science education.