Random Samples

Science  15 May 2009:
Vol. 324, Issue 5929, pp. 863

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  1. Busting the Bumblebee Bushwa


    There's an old but persistent myth, based on calculations from 19th century aerodynamic theory, that bumblebees shouldn't be able to get their heavy bodies airborne with their teeny wings. Computer modelers have tried to explain how they do it, and now scientists at the University of Oxford have captured bumblebee flight in vivo.

    Biomechanicist Richard Bomphrey and colleagues trained bees to fly between a hive and pollen-rich flowers in a smoky wind tunnel while high-speed video cameras captured the swirls of air, or vortices, over the beating wings. It turned out that bumblebees are very inefficient fliers. Unlike most flying animals, they “use the wings on each side independently,” says Bomphrey, which means that they do not connect the airflow over their wings into a single vortex that would speed them on. Such flight requires a lot of energy, supplied by bumblebees' hefty thorax muscles and energy-rich diets.

    Bomphrey speculates that the bees have sacrificed efficiency for “increased control whilst hovering at flowers.” Or the large thorax needed to carry pollen may prevent airflow from linking over it. With this study, in the May issue of Experiments in Fluids, “we now have more information about the flows round bumblebee wings than any other animal,” says co-author Adrian Thomas.

    “The finding sounds indeed interesting,” says biologist Fritz-Olaf Lehmann of the University of Ulm in Germany. But he cautions that three-dimensional flow measurements would be more informative than the 2D smoke trails that the Oxford group studied.

  2. Into the Depths


    On 23 May, a new crewless submersible will leave Guam on a trip that will include an attempt to explore the deepest part of the world's oceans: the 11,000-meter Challenger Deep in the Pacific Ocean's Mariana Trench.

    Nereus will have to withstand the pressure of roughly 1000 atmospheres—equivalent to “three SUVs standing on your big toe,” says Andy Bowen of the Woods Hole Oceanographic Institution in Massachusetts, one of the designers.

    There have been only two prior attempts to go this deep. In 1960, two men spent 20 minutes at the bottom in the bathyscaphe Trieste. In 1995, Japan's crewless submersible Kaiko made a brief visit. Nereus will be the first equipped to roam around mapping Challenger Deep, with batteries enabling it to operate autonomously for 20 hours and cover about 70 kilometers, Bowen says. The vehicle, which carries stacks of disposable steel plates as ballast, will also be tethered to the mother ship by a 40-km-long fiber-optic cable for remote operation so that it can collect samples and send back pictures.

  3. DNA on the Block

    When J. Craig Venter became the first person to sequence his genome in 2001, it took his company, Celera Genomics, a year and cost $100 million.

    This week, a European man won an auction on eBay with a bid of $69,000 to have his whole genome sequenced and analyzed by Knome Inc. in Cambridge, Massachusetts.

    The company, which usually charges $99,500 per genome, will donate the proceeds to the X PRIZE Foundation. “The cost of generating sequence data has been in an absolute free fall” as technology advances, says Knome CEO Jorge Conde. The foundation plans to push the process further by awarding $10 million to the first team that can sequence 100 human genomes in 10 days for $10,000 each.

    One company promises a $10,000 genome by next year and predicts that the figure will plunge to $1000 in 5 years, says geneticist Yoav Gilad of the University of Chicago in Illinois. At such prices, researchers are salivating at the thought of finding out, for example, whether different populations evolved different versions of genes to adapt to various diseases or diets—research that will help usher in a bold new era of personalized medicine.

  4. Chancellor Turnover At UC


    Two University of California (UC) institutions are getting their first female chancellors this summer. At UC San Francisco, Susan Desmond-Hellmann, 51, (above) will replace J. Michael Bishop, 73, who is stepping down after 10 years. As a cancer researcher and executive at the pioneering biotech company Genentech, Desmond-Hellmann played a key role in ushering blockbuster cancer drugs—such as Herceptin, Rituxan, and Avastin—to market. Desmond-Hellmann, a hot commodity who shows up perennially on Fortune's list of powerful businesswomen, was leaving Genentech as part of the leadership shakeup following the company's acquisition by Swiss drugmaker Roche.

    And last week, UC regents approved the appointment of Linda Katehi as chancellor of UC Davis. Katehi, 55, is currently a professor of electrical and computer engineering and provost at the University of Illinois, Urbana-Champaign.