News this Week

Science  22 Apr 2005:
Vol. 308, Issue 5721, pp. 476
  1. INFLUENZA

    Test Kit Error Is Wake-Up Call for 50-Year-Old Foe

    1. Martin Enserink

    Once again, the threat of a flu pandemic made headlines around the world last week, after an influenza A strain called H2N2, which caused the “Asian flu” pandemic of 1957, was accidentally sent to thousands of diagnostic labs. Although experts agree that the episode posed a low risk of a public health catastrophe, it did put an underappreciated question squarely on the agenda: What should the world do with H2N2, a virus not seen in humans since 1968 that is becoming a slightly bigger threat every year?

    Jolted into action, the World Health Organization (WHO) says it will soon issue recommendations to bump up safety procedures in labs working with the virus. It will also ask so-called culture collections to remove H2N2 from their catalogs, at least temporarily while the issue is under debate. (The American Type Culture Collection in Manassas, Virginia, already did so “as a precautionary measure last week, a spokesperson said.”)

    For the long term, WHO plans to reduce the risk of the virus escaping from the thousands of labs storing samples; it might even consider a massive roundup of remaining stocks, akin to the worldwide destruction campaign undertaken after smallpox was eradicated. “It's a peculiar situation,” says WHO's principal flu scientist Klaus Stöhr. “We have to ask ourselves: What are we going to do with H2N2 for the next 100, 200 years?”

    The kits containing the H2N2 strain were provided by the College of American Pathologists in late 2004 and early 2005 to 3747 labs enrolled in programs that help demonstrate their ability to correctly identify unknown pathogens. It's still unclear why H2N2, and not a current influenza A strain, ended up in the panels, produced by Meridian Bioscience in Cincinnati, Ohio. On Monday, WHO said that the kits had been destroyed in all 18 countries outside the United States that received them; destruction in U.S. labs, which received the vast majority, was expected to be completed shortly.

    All gone.

    The emergence of H2N2, known as the Asian flu, caused empty classrooms in 1957. The virus reigned for 11 years before being replaced by H3N2.

    CREDIT (RIGHT): © BETTMANN/CORBIS

    Although widely described as a “killer strain” in the press, H2N2 was mild as pandemics go when it swept around the globe 48 years ago. The reason that it killed an estimated 1 million to 2 million people, mostly elderly, was not its inherent virulence but because no one had any immunity to it, says Stöhr. At the time, H2N2 completely replaced H1N1, the influenza strain that had burst onto the scene in a much more lethal pandemic in 1918. H2N2 in turn was replaced by H3N2 during the so-called “Hong Kong flu” pandemic of 1968. In 1977, H1N1 reappeared—the result of an escape from the lab, most flu experts think—and since then H3N2 and H1N1 have occurred side by side (see graphic, above). The annual flu vaccine is designed to protect against the most recent versions of both strains and the less fickle influenza B virus.

    Researchers don't know what would happen if H2N2 reappeared in the human population right now. No one born after 1968 would have immunity, but the elderly would still have some protection. “I certainly wouldn't expect a full pandemic,” says Alan Hampson of the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne, Australia. But H2N2 could become established along with the other circulating strains, he says, complicating vaccine production even more.

    Moreover, as each year passes, the risk of a full-blown pandemic rises a notch, says Sylvie van der Werf, a flu researcher at the Pasteur Institute in Paris. Yet in labs around the world, H2N2 is still actively studied under biosafety level (BSL) 2 conditions, a relatively low degree of protection. “People have worked with this for many, many years, not realizing the situation is getting more and more dangerous,” says van der Werf.

    WHO has drawn up tougher safety recommendations that would require BSL-3 for certain operations with the virus, Stöhr says; they are currently being circulated among experts for comments. But H2N2 is also stored in samples in hundreds or thousands of labs around the world, a problem that WHO discussed internally last year until more urgent issues put it on the back burner. “Now, we're going to reprioritize this,” says Stöhr. Countries will be asked to make sure that remaining samples are either destroyed or stored and handled properly.

    That effort might eventually evolve into a much larger, more formal exercise to expunge the virus from freezers where it doesn't belong, perhaps supported by a resolution from the World Health Assembly and a verification procedure. Such a process eventually reduced the number of labs holding the smallpox virus to just two in the 1980s; a comparable but less drastic campaign is beginning for poliovirus, the next candidate to be wiped from the planet. But it's not clear that the risk would warrant such a massive operation for H2N2, says Stöhr.

    It's also not clear how long H2N2 will remain a prisoner. Lab accidents aside, some believe that given the cycling of strains witnessed in the 20th century, nature itself is bound to relaunch H2N2 into the human population at some point. That would make much of the new debate moot.

  2. AVIAN INFLUENZA

    Outbreak in Northern Vietnam Baffles Experts

    1. Dennis Normile

    World Health Organization (WHO) officials are warily watching an apparent change in the pattern of human infections with the H5N1 avian influenza virus in northern Vietnam. In contrast to the devastatingly high mortality rate of 70% seen previously, the fatality rate in northern Vietnam has plummeted to about 20% since January, according to WHO's office in Hanoi. The cases are occurring in larger clusters—for instance, among five members of one family. In addition, the disease, which has been concentrated among children and young adults, is now afflicting patients of all ages. Such changes suggest that the virus could be evolving to become “less virulent and more infectious,” says Peter Cordingley, a spokesperson for WHO's Western Pacific Office in Manila.

    WHO officials say there is still no evidence of human-to-human transmission, which could trigger a deadly pandemic. Even the family clusters seem to have been exposed to a common poultry source. “But the pattern of clusters with people getting mildly sick and relatively low mortality is something we haven't seen before in other countries or even in other parts of Vietnam,” says Cordingley. However, his WHO colleague in Hanoi, epidemiologist Peter Horby, warns that the pattern could be the result of better surveillance. Viral samples from recent northern Vietnam patients have been sent to the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, for comparison to previously recovered samples. Results may be available during the week of 18 April.

    Family affairs.

    Nguyen Si Tuan, 21 (left) and his sister, Nguyen Thi Ngoan,14, are one of a number of family clusters of H5N1 cases in northern Vietnam that have alarmed officials.

    CREDIT: STR/AP PHOTO

    Viruses often adapt to their hosts and become less virulent over time. One evolutionary theory, Cordingley explains, is that for the virus to thrive in humans, it can't kill so many of its victims. Although lower mortality may sound reassuring, “even if there is a huge drop in the fatality rate, [a pandemic] would be devastating,” warns Scott Dowell of the International Emerging Infections Program, a collaboration of Thailand's Ministry of Health and the U.S. CDC.

    International reinforcements are finally arriving in Vietnam; they could help sort out just what is happening. A Canadian team with portable testing labs will bolster the country's own capabilities. And a trio of infectious-disease specialists from the United States, New Zealand, and Australia arrived the week of 11 April to advise the government on public health strategies.

    But offers for help on the animal health side are not as forthcoming, says Anton Rychener, the representative of the U.N. Food and Agriculture Organization in Hanoi. One puzzle is why human cases have increased even as outbreaks among poultry have decreased, he says. Another worry is that common chickens may be acquiring resistance, which could enable them to spread the disease asymptomatically. Yet he is unaware of any offers of help from the international community. Technical and financial support is particularly critical to prepare for large-scale poultry vaccination campaigns that might help minimize the chances of humans being exposed to the virus.

  3. U.K. SCIENCE

    Industry-Academic Drug Screening Plan Targets CJD

    1. Eliot Marshall

    CAMBRIDGE, U.K.—Through mergers and buyouts, GlaxoSmithKline has amassed a huge collection of potential drug compounds and now seems ready to let outsiders glimpse this precious hoard—if the cause is right. Last week the U.K.-based drug giant made what it is calling an “unprecedented” deal to let an academic lab scan its million-plus compounds in hope of finding a treatment for Creutzfeldt-Jacob disease (CJD), the brain-destroying illness caused by prions. The leader of the drug screening project, to be funded initially for 3 years by the U.K.'s Medical Research Council, is prion expert John Collinge of University College London (UCL).

    The plan has been “in the works for some time,” says Frank Cooper of Collinge's lab at UCL. But the details are not yet fully worked out. Glaxo spokesperson Gwenan Evans says the company will share data on its compounds and send robotic technicians scurrying through four major U.S. and European facilities to gather up whatever Collinge's lab requests. Evans predicts that the company will turn over a large number of samples. Its capacity is large: “We did over 100 million screens last year,” she notes. Glaxo will retain ownership of the compounds, Evans says, but would likely negotiate a no-profit deal if a therapy proved worthwhile.

    Project leader.

    UCL's John Collinge.

    CREDIT: MEDICAL RESEARCH COUNCIL

    Others have already started down this path, notably Byron Caughey, a prion researcher at a U.S. National Institutes of Health laboratory in Hamilton, Montana. Caughey says he's screened “thousands” of compounds already but hasn't yet found one that shows much benefit in animals if given after symptoms appear.

    CJD and the related “variant CJD” (vCJD), which has been linked to prion-infected beef, are frightening diseases. Death follows soon after the symptoms; deteriorating muscle control and rapid dementia. In Britain, where more than 179,000 cattle in the food chain were confirmed as carrying prion disease in the 1980s and 1990s, vCJD created shock waves. But its toll has been small compared to other diseases: About 150 people have been affected. And that is why the search for a cure is unlikely to get a push from the profit motive.

  4. COSMOLOGY

    Counterattack Heats Up Dispute Over 'Dark Energy'

    1. Charles Seife

    Is dark energy an illusion? “I'm not willing to bet my life on it yet,” says Edward Kolb, a physicist at the Fermi National Accelerator Laboratory in Batavia, Illinois. “I would bet my collaborators' lives, though.” In mid-March, Kolb and three Italian collaborators posted a provocative paper arguing that dark energy—the mysterious antigravity force that makes the universe expand ever faster—is actually a byproduct of enormous ripples in the fabric of spacetime. Kolb's paper created ripples of its own, and now two theorists from Princeton University argue that Kolb's team made an accounting error that invalidates the result.

    “They essentially didn't include all the terms of the analysis,” says Uros Seljak, lead author of the antiripple paper. “There's too many papers out there discussing the issue. We thought it was time to make it clear what could and could not be demonstrated.”

    Kolb's paper, which appeared on the arXiv preprint server (http://www.arxiv.org/), suggested that dark energy—whose effects have been observed by supernova hunters and other astronomers—is not really an energy or a substance. Instead, Kolb says, enormous “perturbations” or ripples in spacetime much larger than the observable universe cause the accelerating expansion of the universe. These ripples, which were caused by the rapid period of inflation just after the big bang, would mimic the fluidlike substance scientists now call dark energy.

    Dark-horse theory.

    Edward Kolb (right) thinks the main ingredient in physicists' recipe for the universe may not exist.

    CREDITS (LEFT TO RIGHT): ADAPTED FROM ROCKY KOLB; FERMILAB

    Kolb's proposal made headlines and generated a flurry of follow-up papers from physicists around the world. But the attention might be premature, argue Seljak and his colleague, Princeton physicist Chris Hirata. In a paper also posted on the archive, they launched a two-pronged attack on the Kolb hypothesis.

    First, using a powerful equation derived from those of general relativity, the two derive a “no-go” theorem that says that huge ripples can't make the universe expand faster and faster. “The equation shows they cannot lead to acceleration,” says Seljak. “You cannot have acceleration with only ordinary matter” in the universe; there has to be dark energy.

    Next, they attack Kolb's mathematics. Seljak and Hirata argue that in the intricate mathematical calculations leading to the result, Kolb and colleagues inadvertently left out some crucial terms that exactly cancel the effect that they are claiming. “They have been fooled into thinking that there's no cancellation,” Seljak says. “These things happen. It's not an easy calculation.”

    Some physicists, such as Edmund Bertschinger of the Massachusetts Institute of Technology, say Seljak and Hirata have put the matter to rest. “This is definitive in my mind,” he says. Kolb, however, holds firm. “I think the no-go theorems eventually will go,” he says, adding that he believes Seljak and Hirata have themselves made subtle errors that invalidate their criticisms. “But their work is sharpening our thinking, and we are writing another paper.” Whether or not dark energy is making the universe accelerate, the debate over dark energy is itself getting rapidly larger.

  5. HIGH-ENERGY PHYSICS

    Latest Data Deal 'Pentaquark' Sightings a Fresh Blow

    1. Charles Seife

    TAMPA, FLORIDA—The elusive pentaquark may be about to disappear. A new result presented at a meeting* here provides the strongest evidence yet that the much-studied θ+ (theta-plus) particle is just a statistical mirage.

    “We don't see a structure corresponding to the θ+ in this region,” says Raffaella De Vita, a physicist at Italy's National Institute for Nuclear Physics in Genova. The new data, from an experiment at the Thomas Jefferson National Laboratory (JLab) in Newport News, Virginia, don't completely rule out the pentaquark, De Vita says. But they do undermine one line of support for the particle's existence and have a much higher statistical significance than the original sightings did. “There's lots of positive results with mediocre statistics, and now one case that can put a nail in it,” says Kenneth Hicks, a physicist at Ohio University in Athens who is working on another pentaquark experiment at JLab. “But it's not closing the door just yet.”

    The pentaquark saga began 2 years ago when a Japanese experiment, SPring-8, seemed to catch a glimpse of a particle, θ+, that couldn't be made of two- or three-quark ensembles like all the quarky matter scientists have seen. Within months, other experiments had announced nearly a dozen more sightings of the particle (Science, 11 July 2003, p. 153). After data from earlier particle-physics experiments failed to show the θ+ or related exotica (Science, 19 November 2004, p. 1281), physicists awaited the results from several JLab experiments tailor-made to find the pentaquark.

    De Vita revealed the results of the first of those experiments, known as g11. In g11, physicists shined gamma rays at a target full of protons; in theory, a collision between a photon and a proton could create a θ+. In 2003, a German collaboration in Bonn using a similar setup claimed to have produced about 60 pentaquarks, a nearly 5-standard-deviation detection. But g11's much more thorough search found nothing. There were huge spikes in the data corresponding to other particles, De Vita says, but none where the θ+ should have been.

    Another round of JLab results might seal the pentaquark's fate. Hicks says he and colleagues are “very close” to finishing an analysis of data from an experiment that used targets rich in deuterons, atomic nuclei consisting of a proton bound to a neutron. There are theoretical reasons to think deuteron targets might produce θ+ particles more readily than proton ones do, says Gerald Miller, a physicist at the University of Washington, Seattle. “If you don't see it in the deuteron, then it's very bad news if you're a pentaquark fan,” Miller says.

    “I hope the issue will be settled soon,” says Curtis Meyer, a physicist at Carnegie Mellon University in Pittsburgh, Pennsylvania. “But I'm not going to buy any pentaquark stock right now.”

    • *American Physical Society April Meeting 2005, 16–19 April.

  6. HIGH-ENERGY PHYSICS

    Unspeakable State of Matter Starts to Reveal Itself--But for How Long?

    1. Charles Seife

    TAMPA, FLORIDA—Reporters from around the world gathered to hear the announcement, but it didn't come. There was no white smoke, no pronouncement: “Habemus quark-gluon plasma.” At a press conference here* on 18 April, scientists working on the Relativistic Heavy Ion Collider (RHIC) celebrated the discovery of a new state of matter not seen since the first moments after the big bang—although they stopped short of claiming to have sighted a long-sought quarry, a quark-gluon plasma. However, the excitement was tempered by a frightening budget profile for nuclear physics and an uncertain future for Brookhaven National Laboratory, the Department of Energy (DOE) facility in Upton, New York, that hosts RHIC.

    RHIC, which was conceived in 1983, smashes atoms together at speeds close to the speed of light. Scientists hoped the concentrated energy of the collisions would momentarily melt the protons and neutrons of the nuclei into their constituent quarks and gluons, creating a quark-gluon plasma.

    After years of running, RHIC scientists certainly saw something new (Science, 20 June 2003, p. 1861; 24 December 2004, p. 2180). Jets of particles flying away from the collision seemed to be moving through a sticky goop rather than through a group of hard protons and neutrons as would ordinarily be the case. Furthermore, after the collision, the system behaved like an expanding puddle of fluid rather than a swarm of particles. “It's an ideal liquid … with essentially no viscosity,” says Sam Aronson, Brookhaven's associate laboratory director for high-energy and nuclear physics. “[It is] as perfect a fluid as calculations would allow.”

    Surprise.

    Debris from colliding gold atoms reveals a nuclear puree thicker than physicists expected.

    CREDIT: BROOKHAVEN NATIONAL LABORATORY

    It was also a surprise. “We expected a hot and dense gas,” says Aronson. Instead, the unshackled quarks and gluons are interacting with each other much more strongly than anticipated. As a result, the RHIC scientists could not agree to put the label “quark-gluon plasma” on the substance.

    They still can't. “Yes, I think it's a quark-gluon plasma,” says Aronson. “The theoretical community—large parts of it—say this is it.” Experimental physicists, however, want more direct evidence that the quarks and gluons are roaming completely free. “To some degree, it's a matter of taste,” he says. “I think it'll be resolved pretty soon.”

    Meanwhile, scientists are already figuring out some of the puzzles that the new state of matter has yielded, including a baffling difference in the behavior of two-quark mesons and three-quark baryons created in the collision (Science, 25 October 2002, p. 718). “A perfect fluid expands very fast, and the various elements of the fluid have the same velocity,” says Dmitri Kharzeev, the leader of Brookhaven's nuclear theory group. “This means that the heavy particles get a bigger boost than the light ones.”

    But RHIC physicists may not get a chance to study the new state of matter for much longer. DOE's high-energy physics budget request for 2006 cuts funding by more than 8%, and the run time for the RHIC accelerator will drop from 30 weeks to 12 weeks. Aronson says tight budgets will likely force the lab to lay off about 40 people, or 10% of the staff operating RHIC. And a subcommittee of DOE's Nuclear Science Advisory Committee is currently mulling over the future of nuclear physics: With current budget prospects, the department may have to choose between closing Brookhaven and closing the Thomas Jefferson National Accelerator Facility in Newport News, Virginia.

    “It's tragic that one has to cut funding for research when such tremendous progress is being made,” laments Wit Busza, a physicist at the Massachusetts Institute of Technology who works on one of the four experiments at RHIC.

    • *American Physical Society April Meeting 2005, 16–19 April.

  7. MOLECULAR BIOLOGY

    Human RNA Slows Down a Primate Retrovirus

    1. Jennifer Couzin

    A multiyear search has led a 30-something molecular biologist and his colleagues to a new way that human cells fend off viruses. A similar defense system, called RNA silencing because short RNA molecules shut down specific genes, is known to protect plants and insects from viruses, but until now a similar immune mechanism hadn't been detected in mammalian cells.

    On page 557, Olivier Voinnet of the CNRS Institute of Plant Molecular Biology in Strasbourg, France, and his team describe a single so-called microRNA, out of the hundreds of different kinds of microRNAs in human cells, that appears to restrict the proliferation of a retrovirus, the viral family to which HIV belongs. Voinnet and others suspect that additional mammalian microRNAs could also have antiviral talents. The work may even explain why it's been tough to identify the roles of so many human microRNAs: They might target the genetic material of foreign viruses, not human genes.

    “This microRNA may be another arm of immunity,” says Shou-Wei Ding of the University of California, Riverside, who reported in 2002 that similar RNAs control viruses infecting fruit flies.

    This microRNA is apparently a nonlethal weapon. By shutting down viral genes, it reins in but does not kill a virus, notes David Baulcombe of the Sainsbury Laboratory in Norwich, U.K., who helped identify an RNA-silencing defense system in plants in the late 1990s.

    It was graduate work in Baulcombe's lab that drew Voinnet to the challenge of finding an RNA-based antiviral defense in mammals. He selected a primate retrovirus called primate foamy virus type 1 (PFV-1); relatively harmless to humans, it doesn't infect people unless they're bitten by a monkey, Voinnet says.

    Viral suds.

    A primate virus creates a foamy residue by killing cells.

    CREDIT: C. H. LECELLIER ET AL.

    Working with postdoc Charles Lecellier, Voinnet first used a viral protein called P19 to determine whether human cells even use RNA silencing against viruses. Many plant viruses produce P19 as one way to squelch a plant's RNA silencing system and give themselves the upper hand. Voinnet's team expressed P19 in some human ovarian cancer cells but not in others, then infected all the cells with PFV-1. In the P19-making cells, the virus replicated much more easily, suggesting that the protein had stymied some defense that continued to work in the normal cells.

    Here, however, the team's findings diverged from those in plants and insects. In their version of antiviral RNA silencing, plants and insects turn a virus's genetic material back on itself. Many viruses replicate by creating double-stranded RNA copies of their genomes; infected plant or insect cells contain enzymes that chop up this viral RNA into smaller strands that target the genetic material of the virus and destroy it. But to Lecellier and Voinnet's surprise, their team failed to find small RNA molecules derived from PFV-1 in the human cells.

    A Spanish friend of Voinnet, Cesar Llave, a plant molecular biologist at the Spanish Research Consul in Madrid, then told him about a recent find: Several plant microRNAs, Llave had just determined, match viral genomes. This left Voinnet wondering whether human cells could directly manufacture small RNAs that thwart PFV-1. Then there would be no need to exploit the virus's own RNA, as plants and insects can. The theory was especially appealing because a single mammalian microRNA might target multiple kinds of viruses.

    A comparison of PFV-1's RNA genome and human microRNAs revealed several microRNAs that could potentially silence PFV-1 gene expression. Indeed, when the researchers blocked one of the microRNAs, miRNA-32, the virus nearly doubled its replication rate in cells. Voinnet's group also found that PFV-1 makes a protein called Tas that seems to suppress the microRNA's ability to tackle the virus.

    Still, the antiviral potency of miRNA-32 remains unclear. Because PFV-1 infects primates, not humans, researchers need to test whether the virus provokes the same RNA-silencing response in primate cells, says Ben Berkhout, a retrovirologist at the University of Amsterdam in the Netherlands.

  8. HIGHER EDUCATION

    Bill Offers Break on Loans to Boost Study of Science

    1. Yudhijit Bhattacharjee

    An estimated 100,000 college graduates could save up to $10,000 each under proposed federal legislation to increase the number of U.S. citizens pursuing science and engineering careers.

    The bill, introduced last week in both the U.S. House and Senate, would forgive the interest on federal loans for science, technology, engineering, and mathematics (STEM) majors who work in science-related occupations for 5 years after they graduate. If passed, the legislation (H.R. 1547 and S. 765) would create the largest program of its type in the history of U.S. higher education. But some observers say that the amount is too small to steer students into science careers.

    Several federal agencies already offer a variety of scholarship and loan forgiveness programs to attract more U.S. citizens into the sciences. Some have paid off, contributing to a 10% increase in the number of domestic students earning STEM degrees from 1991 to 2001, but policymakers say more are needed. Under the Math and Science Incentive Act of 2005, each STEM major would receive a waiver of up to $10,000 in loan interest in exchange for agreeing to work as a science or math teacher or as a STEM professional for five consecutive years. The program would be funded by the Education Department, which already runs a similar program that erases up to $17,500 in student loans in return for 5 years of teaching in an impoverished school district.

    “We understand incentives in baseball, basketball, and football,” says former House Speaker Newt Gingrich, whose new book Winning the Future inspired Representative Frank Wolf (R-VA) to propose the legislation. “There's no reason why incentives won't work in education.”

    Others are not so sure. Economist Anthony Carnevale, a senior fellow at the nonprofit National Center on Education and the Economy in Washington, D.C., calls the legislation “a symbolic gesture” and doubts it will influence students who aren't already headed in that direction. “Few students make a career decision based on how much interest they might be able to save on a loan 10 years down the road,” he says. Naga Kodali, a collections manager for the federal Perkins student loan program at the University of Maryland, College Park, agrees. “If you want to entice students to major in a discipline that requires significant academic effort, you have to offer a comprehensive financial package,” he says.

    Congress followed a similar line of reasoning in last year's Taxpayer-Teacher Protection Act, which more than tripled the amount forgiven under the Education Department's program to attract qualified math and science teachers to low-income schools. “The feeling was that we needed a better incentive,” says Susan Sclafani, assistant secretary of vocational and adult education at the Education Department.

    A successful loan-forgiveness program could have the unintended negative effect of crimping the flow of students into graduate school, worries Daryl Chubin, director of the Center for Advancing Science and Engineering Capacity at AAAS, the publisher of Science. “Students would presumably enter the workforce immediately after earning the baccalaureate,” he says. Forsaking graduate school, he adds, could ultimately put these students at a disadvantage in a competitive job market.

  9. ECOLOGY

    Sucrose-Free Sips Suit Acacia Ants

    1. Elizabeth Pennisi

    The thorny acacia tree has strong allies: vicious, centimeter-long ants whose nasty bite scares off plant-eating animals and also humans. In return for defending acacias, the ants get free meals and places to live. The key to this sweet deal is the sucrose-free nectar provided by the plant, says Martin Heil, an ecologist at the Max Planck Institute for Chemical Ecology in Jena, Germany. As he and his colleagues report on page 560, a sucrose-degrading enzyme produced by the acacia customizes its nectar to appeal to the right ant partners. The defensive-minded ants that protect the tree prefer their nectar without sucrose, while other ants do not, the researchers found.

    Furthermore, the acacia ants have actually decreased their own production of the same sucrose-degrading enzyme, reinforcing this particular pairing of insect with plant. The work “gives one of the first examples of a biochemical basis for behavior difference in plant-insect mutualisms,” says Robert Thornburg, a biochemist at Iowa State University in Ames. “It shows that coevolutionary trends can be underlain by biochemistry.”

    Biologists have documented many cases of coevolution, wherein two species provide for each other and through time develop mutual dependency. Researchers have long known that acacias and Pseudomyrmex ants co-mingle: The ants fend off herbivores and in return live inside the safety of Acacia's thorns and eat the plant's nectar. Because each seedling must reestablish this relationship, the plant must have a way to attract the right ants, Heil explains.

    Feeding station.

    In return for fending off the acacia's enemies, ants feast on its nectar-filled globules.

    CREDIT: M. HEIL ET AL.

    Wilhelm Boland, a chemist at the Jena institute and Heil's collaborator, proposed that the key lies in the seedling's extra floral nectar. Working at two sites in Mexico, Heil exposed Pseudomyrmex ants and other ants to nectars from four swollen-thorn acacia species and from three other Acacia species that don't depend on the specialized ants. He also tested all the ants' preferences for solutions containing varying kinds and amounts of sugar.

    All 11 of the ant species that don't live on swollen-thorn acacias bypassed those trees' nectar, whereas the two species of acacia specialists went right to it and, for the most part, rejected the other nectars. The various ants differed in their tastes for the sugar mixtures as well, says Heil. The nonresident ants headed for solutions filled with sucrose, whereas the acacia ants lapped up solutions lacking this particular sugar. When Heil's team added sucrose to the swollen-thorn acacia's nectar, the two groups of ants switched roles.

    Heil and his colleagues attribute the sucrose-depleted nectar of the acacia to an enzyme called invertase, which is secreted into the nectar by the plant and breaks down sucrose into glucose and fructose. Invertase activity was 10 times greater in the nectar of the swollen-thorn acacias than in the nectar of plants that don't have ant partners.

    “This study reveals that specificity can be achieved relatively simply,” says Anurag Agrawal, an ecologist at Cornell University. He predicts that other organisms also home in on the sucrose-poor nectar and coexist with the ant-plant pair. “Though the relationship is specific, it is unlikely to be purely a two-species interaction,” says Agrawal.

    Diane Davidson, a tropical ecologist at the University of Utah in Salt Lake City, calls the Heil study “rigorous” but wonders if the acacia's ant partners add sucrose-degrading microbes to the nectar. Other strategies could also be used by acacias, she notes. For example, some plants secrete wax that only specialized “wax runner” ants can travel on.

    Nonetheless, says Thornburg, Heil and his colleagues “are actually starting to get to the mechanisms” of mutualism. How sweet.

  10. CLIMATE CHANGE

    Global Warming Skeptic Argues U.S. Position in Suit

    1. Eli Kintisch

    The U.S. government has enlisted an outspoken skeptic of global warming in a legal fight with environmental groups over U.S. funding for overseas energy projects. The move has angered several prominent climate researchers, however, who say the government's arguments fly in the face of scientific consensus about both the causes and possible consequences of global warming.

    On 29 April, a federal district court in San Francisco will hear a case (Friends of the Earth v. Peter Watson) about whether the National Environmental Policy Act (NEPA) should apply to projects supported by the Export-Import Bank and the Overseas Private Investment Corporation. The act requires the government to assess actions that could alter the environment. The plaintiffs in the case, which include several environmental groups and four western U.S. municipalities, argue that the federally supported projects—including oil drilling, pipelines, and commercial power plants—contribute to global warming, which in turn affects U.S. economic interests and its citizens. That connection is essential to establish their legal right, or standing, to bring suit.

    “Impacts … will include sea level rise, … disturbances of ecosystems, … [and] an accelerated reduction of water storage in winter snowpack.”

    —Michael MacCracken, in brief for plaintiffs

    CREDIT: MICHAEL MACCRACKEN

    To counter that claim, the Justice Department argues that “[t]he basic connection between human induced greenhouse gas emissions and observed climate itself has not been established.” It buttresses its case with a 41-page statement from David Legates, head of the Center for Climatic Research at the University of Delaware, Newark.

    Legates begins by attacking the evidence for the 0.6°C rise in temperature in the 20th century cited by the Intergovernmental Panel on Climate Change (IPCC) in Geneva, Switzerland, in its 2001 report and by the plaintiffs. The proximity of temperature gauges to cities, he says, has artificially elevated reported temperatures. He also points to natural variability as an important factor, citing a 2004 study that suggested solar variability may have contributed up to 0.25°C of the recent warming. As for future impacts, he says surface temperatures in Greenland are falling, coral bleaching is a beneficial response to stress, and the impact of droughts has been relatively benign in the 20th century. Legates says a Canadian climate model that plaintiffs cite to show potential changes in surface temperatures and moisture across North America is “extreme” and “overstated.”

    The plaintiffs counter with a 45-page brief from climate researcher Michael MacCracken, former head of the Office of the U.S. Global Change Research Program. In an interview, MacCracken called the Legates document “an attempt to go back and reargue the IPCC.” Core findings of the IPCC, he says, have been repeatedly confirmed, including the 0.6°C increase in the last century. The urban heat effect has been discounted and cannot explain the warming oceans, says Thomas Wigley, a climatologist at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado. Legates's arguments on solar variability are “standard skeptic crap” that has been discredited, Wigley declares.

    “Significant questions still remain as to [whether] this … rise in air temperature can be attributed to anthropogenic increases in greenhouse gas concentrations.”

    —David Legates, in brief for government

    CREDIT: PHOTO COURTESY OF KATHY ATKINSON/UNIVERSITY OF DELAWARE

    MacCracken says Legates's assertion that Greenland is cooling is “wishful thinking,” pointing to vast melting around the landmass documented in the recent Arctic Climate Impact Assessment. Severe droughts are on the increase, says IPCC lead author Kevin Trenberth of NCAR. As for Legates's criticism of the Canadian model, MacCracken notes that relevant government agencies have approved the 2000 U.S. National Assessment in which the model was put to use. “It's a selective use of studies and half-truths,” Trenberth says about Legates's arguments.

    In an interview with Science, Legates says he's standing his ground. He questions whether the IPCC represents a true consensus, claiming “a lot of dissenting views.” He defends the studies he cites and attacks the Arctic assessment, which he says ignores natural Arctic cycles. Connecting emissions overseas to stateside impacts is simply tenuous, he maintains, adding that the plaintiffs are being selective in choosing the most dire projections.

    Previous legal attempts to force the government to report carbon dioxide emissions under NEPA, by linking those emissions to climate impacts, have failed. But a 2003 ruling in a suit over natural gas turbines found the failure to disclose CO2 emissions “counter to NEPA.” Earlier this month a federal appeals court heard arguments in a suit that would require the Environmental Protection Agency to regulate CO2 emitted by motor vehicles.

  11. GERMAN SCIENCE

    Plan to Boost University Research Caught in Political Crossfire

    1. Gretchen Vogel

    BERLIN—A bitter dispute over who has responsibility for German universities is blocking a federal government plan to spend nearly €2 billion on cutting-edge research. On 14 April, the latest attempt at compromise ended in disappointment for scientists and university administrators who have been anxiously awaiting the start of a so-called Excellence Initiative designed to boost the fortunes of Germany's most competitive universities, which have suffered decades of tight budgets, aging faculty, and expanding student populations.

    The stakes are high. The proposed initiative would make €1.9 billion ($2.5 billion) available through 2011 under three programs: up to €1 million per year for 40 new graduate schools, €6.5 million yearly for each of 30 “excellence clusters” that would increase cooperation between universities and other research centers, and €21 million a year for 10 universities that develop university-wide strategies to boost themselves to world-class status. The federal government would cover 75% of the program, with state governments covering the rest. An accompanying “pact for research and innovation” would guarantee 3% increases for Germany's nonuniversity research institutes, including the Max Planck Society, through 2010.

    Still waiting.

    The University of Heidelberg is a leading candidate for funding under a stalled program that would support Germany's top universities.

    CREDIT: UNIVERSITÄT HEIDELBERG

    The targeted university funding is a dramatic change in Germany, where decades of egalitarian policies have sought to ensure equal access to universities nationwide and “elitism” has been taboo. In January 2004, however, Research and Education Minister Edelgard Bulmahn, a member of the governing Social Democrats, announced that she wanted to fund a program to create a handful of world-class universities that would attract students and researchers from around the globe (Science, 11 June 2004, p. 1579).

    The German constitution assigns responsibility for universities to the 16 German Länder, or states, and several state leaders—chiefly from the opposition Christian Democratic party—protested, saying the plan overstepped the federal government's powers. Months of negotiations produced the three-pronged funding plan, and state and federal leaders have been near agreement at least twice. Most recently, on 6 April, the science ministers from all 16 states agreed to a final proposal, and it looked as though the plan would go forward. A week later, however, on 14 April, Christian Democrat leaders balked and refused to sign off. In particular, the leader of Hessen, Roland Koch, has said the plan would create an unacceptable “two-tier system” among Germany's 99 universities.

    The continuing blockade is “completely incomprehensible,” says Ernst-Ludwig Winnacker, president of the DFG research funding organization. “A few politicians are …tarnishing the international reputation of German research.” Bulmahn said in a press conference a day after the latest breakdown that she is ready for further negotiations and “will continue the fight.” However, most observers predict that the stalemate will continue at least until after state elections in North Rhine-Westphalia on 22 May—where the Christian Democrats are hoping for a big win that would boost their bargaining power in state-federal disputes.

  12. GENDER EQUITY

    Japan Mulls Workforce Goals for Women

    1. Dennis Normile

    TOKYO—A government advisory committee has suggested that Japan's publicly supported universities and labs set targets for hiring more women and that the government monitor their progress and publicize the results. The idea is to encourage—and perhaps even embarrass—authorities into lifting Japan from last place among industrialized nations in the employment of women scientists. “We need something to encourage more progress in this area,” says Yasuharu Suematsu, former director general of the National Institute of Informatics and head of the panel, which reported this month to the Ministry of Education.

    Current figures from Japan's Statistics Bureau show that women make up just 11.6% of the country's R&D workforce. That percentage is the lowest among the 30 industrialized countries in the Organisation for Economic Co-operation and Development (OECD), in which Portugal leads the way with more than 40%. The U.S. figure is 26%.

    Little women.

    Japan ranks last in the OECD on women in its scientific workforce.

    CREDIT: OECD

    The advisory committee concludes that raising Japan's percentage will require progress on many fronts, including better support for women with families, gender-blind evaluations, and more aggressive efforts to promote women into leadership positions. But as a start, the committee suggests adding targets to the country's next Five-Year Basic Plan for Science and Technology that will govern spending and policy decisions for the half-decade starting next April.

    Mariko Kato, an astronomer at Keio University in Tokyo, worries, however, that the targets will lead administrators to boost numbers by hiring “nonassertive women” for low-ranking positions instead of tackling more fundamental problems. “There is still sexual harassment, and you still hear comments about women being unsuitable for science,” Kato says. “If you don't change the consciousness of men, the environment for women won't change.” Chikako Shingyoji, a female cell biologist at the University of Tokyo who serves on Suematsu's committee, doesn't believe targets are the entire answer. But “setting targets is better than not doing anything,” she says.

    Suematsu agrees that male attitudes are a big obstacle. “Striving to meet targets will mean addressing the question of how to change this consciousness,” he says.

  13. SPACE SCIENCE

    Balancing the Right Stuff

    1. Andrew Lawler

    NASA's new leader comes aboard with a deceptively big budget for science. But size is no substitute for a healthy portfolio. Can Michael Griffin remake the agency's human space flight program without eviscerating research?

    Solar physicist Yohei Yamauchi dreams of finding a permanent job in his field. But his boss at the New Jersey Institute of Technology in Newark recently told him that NASA was cutting the modest grant supporting his work analyzing data on the solar corona, leaving the 38-year-old Japanese-born researcher scrambling for another position. A scientist at another research institute who would like to hire Yamauchi is instead laying off a postdoc because of the same budget constraints.

    Yamauchi's straitened circumstances are a sign of a quiet crisis in NASA's science program that poses a formidable challenge to Michael Griffin, who took over last week as NASA's new administrator. Space agency managers are now chopping more than $400 million out of the 2005 science budget to cover congressional earmarks and shuttle overruns. That means cutting grants, turning off satellites, and postponing nearly a score of planned missions. And the situation is likely to grow more dire in the coming year, as shuttle costs continue to rise and NASA pushes ahead on programs designed to send humans to the moon and eventually to Mars—all on a budget slated to remain nearly flat.

    “There is the potential for serious damage to the future of science at NASA,” says Lennard Fisk, a geophysicist at the University of Michigan, Ann Arbor, who chairs the National Academies' Space Studies Board. Fisk, who led the agency's science program during the Administration of President George W. Bush's father, was one of 17 prominent scientists to sign an unusual manifesto the day before Griffin's Senate confirmation hearing urging NASA to retain its broad-based science program while it pursues the human exploration of the moon and Mars. “The balance between the two modes of exploration, human and robotic, is now threatened,” the manifesto states.

    Griffin—who spoke with some of the concerned researchers a few days before that hearing—echoed that concern at the 12 April hearing. “We as a nation can clearly afford well-executed, vigorous programs in both robotic and human space exploration as well as in aeronautics,” he said. He noted that NASA during the 1960s was not solely focused on the Apollo moon program but had vibrant planetary, earth science, and aeronautics efforts. “We can do it again,” he insisted. The next day the Senate confirmed him as the agency's 11th chief.

    But Griffin also said his top priorities are getting the shuttle back into orbit and building a new human launcher to replace it. He must contend with major aerospace companies, NASA centers, and key lawmakers committed to preserving the jobs that the space shuttle and space station provide, and a president who wants NASA to push ahead with new launchers, lunar bases, and human missions to Mars. And Griffin, unlike his predecessors in the 1960s, almost certainly will not receive budgets large enough to accommodate these competing interests. “He's going to have to choose sides; he can't make everyone happy,” predicts one former NASA administrator. Adds a longtime congressional aide: “He has got quite a challenge to figure out how to make the math work.”

    CREDITS (TOP TO BOTTOM): SPECTRUM ASTRO; NASA; NASA/JPL; NASA/JPL

    Best and worst of times

    Ironically, NASA's science program has never been better funded. One-third of the agency's budget—$5.5 billion—is devoted to science. That's the largest percentage in agency history, notwithstanding new accounting methods that include overhead. Construction of sophisticated robots to examine Mars is under way, a large new space-based observatory to replace the Hubble Space Telescope is well along in the planning, a probe to Pluto will soon be launched, and a fleet of Earth-observing spacecraft is returning unprecedented quantities of data. A new lunar robotic effort is on the books, and science's share of the NASA pie is slated to hit 38% in 5 years.

    That is little solace to researchers such as Yamauchi, however, who are bracing for more bad news. NASA will soon announce a $160 million cut to its 2005 science budget, after making a similar reduction in December. Another $86 million goes to working on a robotic mission to the Hubble Space Telescope, for a total of $407 million. Later this month, an independent group of scientists will tell NASA which earth science missions should be shut down in light of the funding crunch. And this fall, another panel will determine which half-dozen or more of 13 orbiting solar and space physics spacecraft—including the famed Voyager probes—should be turned off. That advice follows NASA's decision to postpone indefinitely work on most long-term missions that aren't heading to Mars or the moon.

    NASA science chief Al Diaz blames the squeeze on congressional decisions, called earmarks, to fund projects not requested by the Administration. “Every 2 years, these earmarks [divert enough money to] eat a mission,” Diaz told a NASA earth science and space science advisory committee science advisory panel on 31 March. “Earmark money clearly could have been used to fund Voyager and Ulysses”—two spacecraft currently on the chopping block. Less than a decade ago, such set-asides accounted for just a few million dollars in the science budget.

    But many scientists say a far bigger threat to broad-based science at NASA is the rising cost of returning the shuttle to orbit and building the space station, coupled with the president's call last year for human visits to the moon and Mars. “It is only going to get worse,” says Princeton University astronomer John Bahcall about raids on NASA's science budget to accommodate human flight. “They will have to dig even more deeply in the science budget; it has only just begun to be mined.”

    The roots of today's woes were put down soon after the Columbia accident in February 2003, when NASA began the long and expensive job of fixing the shuttle. Meanwhile, the White House developed a long-term strategy for the agency that would finish the space station, shut down the shuttle, and send humans to the moon and Mars using a new launcher that would be ready by 2014. Bush said he would pay for the initiative by phasing out the shuttle in 2010 and abandoning the station several years earlier than originally planned. Although the science focus of the exploration effort would be the moon, Mars, and life science research aboard the space station, then-NASA chief Sean O'Keefe insisted that the overall science program would be protected.

    But the Administration's “pay-as-you-go” strategy for its exploration effort, accompanied by modest budget increases for the coming years, began to unravel quickly last year. Although Congress approved the full amount requested by the White House, the costs for getting the shuttle flying again continued to climb, to more than $700 million in 2005 alone, an amount not reflected in Bush's original 2005 request. And Congress packed the NASA budget with pork, including $160 million in the science directorate alone. Meanwhile, cost estimates for robotic missions as well as new technology programs such as the Prometheus nuclear-power system were on the rise.

    CREDITS (LEFT TO RIGHT): NASA/JPL; NASA; NASA; L-3 COMMUNICATIONS INTEGRATED SYSTEMS

    Confronted with an expensive war in Iraq and a swelling budget deficit, the White House asked for less money in 2006 than Bush had pledged to request just 1 year before. And many aerospace companies and lawmakers object to the president's plan to shut down the shuttle in 2010 when a new human launcher would not be ready until 2014. They argue that the 4-year gap is too long. In his confirmation hearing, Griffin pledged to try to speed up construction of that new human launcher, which would undoubtedly cost tens of billions of dollars. Griffin has previously proposed converting the shuttle from a human launcher into a cargo vehicle, which could also entail a major investment.

    Yet neither earmarks nor the human space flight program fully accounts for NASA's science crisis. The Columbia accident occurred as the research community was selling NASA on a new generation of planetary, astrophysics, and earth science missions. To pay for those new programs, the agency planned to spend $1 billion more on science in 2006 than has been requested by the White House.

    Fisk maintains that those achievements, rather than the president's exploration vision, are largely to blame for the current mess. Diaz's predecessor, Ed Weiler, “was too successful,” says Fisk. “He sold programs that required a growth in funding for science that is not now attainable.”

    Crossing the Rubicon

    NASA officials refuse to say exactly how they will allocate the final round of 2005 cuts—a total of $160 million—but the impact is already being felt at U.S. institutes and universities. “I personally elected not to cut ongoing programs and not introduce delays or eliminate strategic programs,” Diaz told the NASA advisory panel. “It is impossible to figure out a more surgical way; the problem is our flexibility is gone. Missions have grown in size and funding has not.” The chief victims, he said, will be operations of existing spacecraft, grant programs, and longer-term plans to build earth science and astrophysics probes.

    In NASA's astrophysics division, for example, managers are struggling to cope with costly technical troubles on spacecraft slated for launch in the next few years along with cuts imposed from above. Anne Kinney, the division leader, late last year squeezed $100 million from her 2005 budget of roughly $1.5 billion to cover earmarks, general reductions, and returning the shuttle to flight. In the past month she has had to find another $58 million in reductions—a task made harder by the fact that the budget year is already more than half over. Two-thirds of the reductions will be assigned to missions and one-third to research and analysis programs. “As long as I've been here, we've never cut research,” says Kinney. “We are crossing the Rubicon.”

    The impact was immediate. The same day that Diaz spoke to his scientific advisers, NASA announced it would cancel this year's solicitation for 5-year, $100,000 grants that allow budding astrophysicists to pursue a broadly framed scientific issue. “For young researchers like me, these long-term programs are absolutely vital,” says one grantee, Bryan Gaensler, a 31-year-old assistant professor at the Harvard-Smithsonian Astrophysical Observatory in Cambridge, Massachusetts.

    Kinney says she had little choice. “Why ask 200 people to send in proposals if you can only accept five?” she adds. NASA is canceling another annual grant program that funds work on data archives from older missions. The agency also put on hold other efforts like the Explorer programs, which fund modest missions from a variety of disciplines at a faster pace than the usual NASA projects. That outrages many space scientists. “This is the lifeblood of innovation and creativity in our discipline,” says Fawwaz Ulaby, an electrical engineer at the University of Michigan, Ann Arbor, and member of NASA's new science advisory committee. “Our community has been saying that the Explorer program is absolutely critical, so that we have some agility to respond” to new research questions.

    Diaz also intended by this fall to turn off seven of 13 operating solar physics missions—including the Voyagers at the edge of the sun's influence—to save a total of $21 million. The probes represent the bottom half of a 2003 ranking of scientific usefulness. But under pressure from the advisory panel, he recently agreed to conduct an extensive outside peer review this autumn before terminating any missions. That extension, warns NASA manager Paul Hertz, puts further internal pressure on the science budget.

    Down to Earth

    Earth scientists hope that their work on a National Academies' decadal plan—an interim version was slated for release this week—will help them persuade the White House and Congress not to abandon their troubled discipline. It will be an uphill struggle. Berrien Moore, a biogeochemist at the University of New Hampshire in Durham who is a co-chair of the decadal panel, calls NASA's current approach “a going-out-of-business sale for earth sciences.”

    He notes that only one of a half-dozen missions planned for launch is clearly going forward. NASA, for example, plans to abandon the Glory mission to study aerosols, a mission championed just last year by former NASA chief Sean O'Keefe, who pledged to speed up launch to 2007 or 2008. “Now we have gone from acceleration to cancellation,” Moore adds. Some planned missions are indefinitely postponed; others were left with money to build an instrument but without funding for a spacecraft to fly on.

    Nor are existing satellites safe. Mary Cleave, who heads the earth science division, predicts that an independent review of several missions to be finished this month will lead to the termination of some of them. At the 31 March advisory meeting, Harvard University atmospheric chemist Daniel Jacob warned that the earth science program is being “decimated.” Diaz called that criticism “a little bit of an overstatement.” But he acknowledged that NASA was focused on “strategic issues,” shorthand for an emphasis on lunar and Mars exploration along with space station life sciences.

    Diaz's policies haven't gone over very well in the space and earth sciences communities. “This is probably just not good budget strategy,” says Fisk. Faced with similar constraints in the early 1990s, Fisk chose to scale back efforts to build large spacecraft to protect more fragile smaller missions, existing spacecraft, and the network of scientists who depend on NASA grants to analyze data. “You can't just fund the flight programs, which mostly funnel money to industry,” he adds. Researchers have yet to grasp the severity of the issue, and Fisk is worried about their reaction. “There is a firestorm coming, and the community does not always respond in an organized way,” says Fisk.

    The first organized response is the 1500-word manifesto timed for Griffin's confirmation hearing. It is the brainchild of Nathan Schwadron, a 36-year-old space physicist at the Southwest Research Institute in San Antonio, Texas, who says he began to worry last fall that NASA's science program—and entire disciplines—were in jeopardy.

    The document argues that Bush's exploration vision shouldn't be confined to the moon or Mars. “Should other forms of space exploration be canceled or curtailed to make this new, but limited, exploration vision possible? We think and hope not,” says the paper. “It is critical that we continue to explore broadly.”

    Schwadron and others say that they are sympathetic to a revamped human space flight program, but that they want to ensure a broader definition of exploration. “It's not the turning toward exploration, it is the turning away from science that's the problem,” says Yale University astronomer Meg Urry. “Some of the most successful science at NASA is languishing, such as the search for dark energy, arguably the biggest revolution in physics in a century.” Scientists like Schwadron and Urry applaud the new goals for the human space flight effort, but they don't want NASA's diverse research portfolio to shoulder the costs.

    NASA managers insist that the president's vision is fundamentally friendly to science. “Science activities are built into the foundation of the exploration vision,” James Garvin, NASA's chief scientist, told the American Astronautical Society at a 29 March meeting in Greenbelt, Maryland. He argues that exploration “is a scientific journey,” citing the ambitious plans for lunar and Mars exploration. And Diaz notes that a series of “road maps” being assembled will lay out the long-term direction of science and be completed in time to influence the 2007 budget submission this fall.

    As he settles into his ninth-floor offices overlooking the Potomac River in downtown Washington, D.C., Griffin must decide how to balance the fiercely competing needs of the traditional space-flight program, the president's new vision, and science involving more than the moon or Mars. The agency's present course, Schwadron predicts, could eventually force a third or more of the people in solar and space physics out of the field. Astrophysicists, biologists, astronomers, and earth scientists express similar concerns. And younger researchers eager for a stable future are getting skittish.

    Scott MacIntosh, a solar physics postdoc at the Southwest Research Institute, can't ignore rumors that the guest investigator program that funds his work may disappear. “I have a background in medical imaging, so I might try to do more cross-disciplinary work,” he says. And MacIntosh is in no position to gamble about his future: “I've got a young kid and another on the way.” NASA's ability to cultivate a new and diverse generation of space scientists like MacIntosh and Yamauchi may hinge on whether Griffin has the right stuff to execute a difficult balancing act.

  14. SPACE SCIENCE

    "We Can Do the Program That the President Has Proposed"

    1. Andrew Lawler

    Calling him “a rare combination of scientist, engineer, and manager,” Senator Barbara Mikulski (D-MD) gave voice to the thoughts of colleagues on both sides of the aisle in speeding Michael Griffin through a Senate confirmation process that took all of 1 day. “He is a rocket scientist—thank god we'll have someone who understands what it is all about!” she proclaimed about the new NASA administrator during his hearing on 12 April.

    That understanding will be put to the test as the 55-year-old aerospace engineer faces a slew of tough decisions (see main text). Sources close to Griffin predict sweeping changes by this summer in NASA's senior management, including new chiefs of science, space flight, and legislative and public affairs. Their boss has already received White House approval to send a shuttle mission to service the Hubble Space Telescope if he deems it to be safe, they add. During the hearing, Griffin laid out his views on several pressing issues facing the agency.

    CREDIT: MARTY KATZ

    Here are excerpts from his testimony:

    • On the space station: “A human space-flight program focused only upon the completion of the space station and the servicing of that station with the shuttle does not qualify as a goal which is worth the expense, the risk, and the difficulty of human space flight. … The president is pledged and I … am pledged to bring the space station to a level of completion consistent with our obligations to our international partners.”

    • On balancing human and robotic programs: “If we continue to receive the president's budget allocations, we can do the program that the president has proposed. We know that we can do it because we've done it. The Apollo years are often looked at as a period when the agency had a single mission focus. That [is] incorrect. During the Apollo years, in addition to executing that program, … we also executed a host of planetary missions in the Mariner, Ranger, Surveyor, Voyager, and Viking Series. We executed earth science missions. … We executed astronomy missions [and an] orbiting solar observatory.”

    • On the Hubble Space Telescope: “I would like to take the robotic mission off the plate. … And so I believe that the choice comes down to reinstating a shuttle servicing mission or possibly a very simple robotic deorbiting mission. The decision not to execute the planned shuttle servicing mission was made in the immediate aftermath of the loss of Columbia. When we return to flight, it will be with essentially a new vehicle, which will have a new risk analysis associated with it and so forth. At that time, I think we should reassess the earlier decision.”

    • On a new human launcher: “Two nations [China and Russia] have now put people into space since the United States has last done so. I don't like that. The program that NASA has outlined so far features a new crew exploration vehicle—we can call it what we will—and it nominally comes online in 2014. I think that's too far out. President Bush said not later than 2014. He didn't say we couldn't be smart and do it early. And that would be my goal.”

  15. ECOSYSTEM MANAGEMENT

    California Tries to Connect Its Scattered Marine Reserves

    1. Amitabh Avasthi

    Researchers hope that new funds, better management plans, and the latest science will help them establish the largest network of marine protected areas in the U.S.

    The 1800-kilometer California coastline supports a spectacular diversity of marine life. So does a sea floor that plunges just offshore to nearly 2600 meters, with sea-grass beds and kelp forests giving way to submarine canyons and deep rock reefs. Add in seasonal winds and complex ocean currents that churn up nutrients for thousands of species from sharks and tuna to squid and rockfish, and the result is an incredibly rich ecosystem—and one of the most productive fisheries in the nation. Can the two coexist? Those working on a new state effort to create a network of marine protected areas (MPAs) hope that the answer is yes. But it won't be easy.

    Once upon a time, the bounty of the sea accommodated both fishers and conservationists. But over the past 2 decades, fish catches have fallen by more than half. An MPA network would set aside part of the ocean to prevent the total degradation of this habitat, foster marine diversity—and perhaps maintain a sustainable fishing industry. The vision is grand. Not only would the network be the largest such system in the nation, but its success “would be a wonderful model” for a national system, says Jane Lubchenco, a marine ecologist at Oregon State University in Corvallis. And last week the group reached its first major agreement: choosing the location of a pilot project.

    Location, location

    California set up its first MPA in 1957, a 35-hectare area near La Jolla in San Diego county. Since then, 104 areas have been added in a piecemeal and uncoordinated fashion. Despite this effort, MPAs cover less than 0.3% of state waters—not enough to make a difference in helping fisheries recover, scientists say. And none of the reserves protects species or habitats in deeper water.

    In 1999, California tried to address the problem with the Marine Life Protection Act (MLPA). One of the law's requirements is to create a network of MPAs along the state's coastline. But a 2002 attempt by the state department of fish and game and outside scientists encountered stiff resistance from commercial and recreational fishers, who objected to the size and area of the proposed MPAs and the fact that they had been largely excluded from the process. One year later an expanded task force tried again, but it ran out of funding before finishing its work.

    Hooked?

    Fishers are worried about the economic impact of new reserves but are playing along for now.

    CREDIT: RICHARD ALLEN

    Last year state officials tapped into a group of foundations led by the Resources Legacy Fund Foundation (RLFF). RLFF is providing most of the $9 million of funding for the new effort—enough to get a first collection of MPAs set up. Its 19-member science advisory team—appointed by an MLPA task force—is chaired by Stephen Barrager of Stanford University and includes fishers and others.

    The group's first challenge was to outline the steps to pick locations for reserves, design their boundaries, and specify how they should be monitored. The guiding principle was that reserves will be more effective as a network rather than isolated, an idea espoused by a 2001 report by the National Academy of Sciences. A network takes into account the movements of adult and larval fish, allowing fish to travel from one reserve to another.

    The California plan calls for locating MPAs based on how fish species migrate and how far their larvae disperse. Scientists are learning those patterns in several ways, such as by tracking larvae and analyzing their DNA from various locations. Other experts such as Mark Carr, a marine biologist at the University of California, Santa Cruz, are conducting tagging studies and analyzing fish otoliths to track the movements of adult fish. His data suggest that the ranges of many rocky reef fishes are less than 5 km. But other fish are known to swim about 10 km a day—implying that the reserves ought to extend into federal waters.

    The plan breaks new ground with its emphasis on deeper-water habitat. It would protect five types of habitat—including submarine canyons and deep rock reefs—at four depth zones. “Many fish use kelp forests as nursery, move deeper as they grow, and return to shallow water for spawning,” says Carr.

    The ultimate shape of the MPA will be determined using bathymetric data, maps of nutrient upwellings, and information on the variety and abundance of species in a habitat. Although previous reserves were irregularly shaped, the plan calls for new ones to follow lines of latitude and longitude—making it easier for fishers to avoid them and enforcement officers to scout for violators. There's no guarantee of sufficient funding for officers and equipment, however. As for monitoring, state fish and game scientists should evaluate MPAs by regularly checking species abundance, habitat quality, and other biological indicators.

    Last week, the task force chose a 300-km stretch of the central coast region, roughly from northern Monterey Bay to Santa Barbara, as its first region of study. Existing MPAs within the boundary will be evaluated and weighed in conjunction with any proposed new sites. The first network could be operational by March 2006.

    Teeming.

    Reserves will be sited where winds dredge up nutrient-rich water (left; blue and violet) that sustains gopher rockfish (right) and other species.

    CREDITS (LEFT TO RIGHT): NOAA COASTWATCH PROGRAM; MARK CARR

    Rough seas

    Although participants say the process has been smooth sailing to this point, they expect the political seas to become more choppy when it comes time to decide the exact location and size of the MPAs. At stake is an estimated $1.4 billion sport and commercial fishing industry, an industry already besieged with dwindling fish stocks, decreasing catches, and increasing regulations. Despite being included, commercial and recreational fishers still worry that large chunks of the ocean could be marked off-limits, says Thomas Raftican, president of the United Anglers of Southern California in Huntington Beach. Indeed, Carr's analysis suggests the need for reserves significantly wider than the 1 km that is now typical.

    One of the most politically contentious and unresolved problems is striking a balance between areas where fishers have quotas and those from which they are banned. Although protecting 20% has become a commonly cited target, some experts suggest that more than 35% of the areas should be no-take zones, citing successful practices in the Great Barrier Reef. Carr hopes to defuse the issue by noting that the size and shape of each MPA will depend on the species, the habitat, and the conservation objectives of both the individual MPAs and the entire network.

    Another major worry is whether the MPAs will boost stocks outside the reserve sufficiently to benefit fishers and win their support. Lubchenco says this “spillover” is likely in California, pointing to increased fish catches outside the Great Barrier Reef and the Florida Keys National Marine Sanctuary. According to Steven Berkeley, a research biologist with the Long Marine Lab at the University of California, Santa Cruz, reserves lead to older and fatter fish, which sustain fish populations by producing more hardy larvae. Early results from a network of 12 MPAs set up in 2003 in the Channel Islands suggest that fish populations outside the reserve are indeed on the rise. But others are skeptical. “There simply are no benefits to commercial fisheries,” contends Raymond Hilborn, a fisheries management expert at the University of Washington, Seattle.

    Despite these uncertainties, almost everybody agrees that MPAs have the potential to be an important tool in marine conservation and fishery management. “They could act as a buffer or insurance against overfishing or a natural disaster,” says Peter Sale, a tropical marine ecologist at the University of Windsor, Canada. People also agree that plowing full steam ahead is the only logical next step.

  16. INFECTIOUS DISEASES

    Crisis of Confidence Hampers Marburg Control in Angola

    1. Martin Enserink

    Experts have everything they need to stop the deadly Marburg outbreak in northern Angola—except trust from the local population

    Vincent Brown has his own way of keeping track of the Marburg virus in Uige, a provincial capital in northern Angola: He counts fresh graves. A daily visit to the town's cemeteries doesn't yield precise numbers, says Brown, an epidemiologist with Epicentre, the Paris-based research arm of Médecins sans Frontières (MSF)—but it does give one a feeling for the trend.

    The reason behind the unorthodox method is simple. In the current outbreak of Marburg hemorrhagic fever, which had caused at least 227 deaths by 15 April, most patients never make it to the hospital. Widespread fear and mistrust of public health authorities and the international teams fighting the disease are leading most families to keep their patients at home. As a result, the virus keeps festering, says Brown, who returned to Paris last week from Uige.

    Four weeks after Marburg was nailed as the culprit, the fight against the virus has become a battle to win the trust of the local population. “It's clearly a bit more difficult than we anticipated,” says Pierre Rollin of the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, which has sent several teams to Angola. But medical anthropologist Barry Hewlett of Washington State University in Vancouver says the difficulties were predictable. “It's often like this,” says Hewlett, who has accompanied medical teams during several outbreaks of Marburg's cousin, Ebola.

    Marburg, which spreads through direct contact with blood and other bodily fluids, isn't like flu, measles, or other highly contagious viruses. Putting patients in strict isolation and checking their close contacts for symptoms daily for at least 21 days—and isolating them as well if they do get sick—will usually end the transmission chain.

    Today, the logistical systems are in place to do just that, says Pedro Pablo Palma of MSF's Spanish branch in Barcelona. MSF has set up a three-compartment isolation unit in the hospital in Uige, for suspected, probable, and confirmed patients. Although hygiene in the rest of the hospital was initially “catastrophic,” Pablo says, with highly infectious corpses piling up in the morgue, the situation has gradually improved.

    Scientific capacity is generally better than in most previous outbreaks of Marburg and Ebola. Researchers from Canada's National Microbiology Laboratory in Winnipeg have set up a field lab in Uige that can test patient samples within a few hours. CDC, meanwhile, has set up a diagnostic lab in Angola's capital Luanda to test any samples that might come in there and to confirm results by the Canadian team. But while the graveyard kept filling up—there were twice as many new graves daily in early April than in March, Brown says—the labs didn't have nearly as many samples as they could have handled, and the isolation unit was virtually empty early this week.

    Staying away.

    Marburg patients aren't coming to an isolation unit in Uige.

    CREDIT: FLORENCE PANOUSSIAN/AFP/GETTY IMAGES

    The lack of trust has several roots. One is that so far, nobody has made it out of the isolation unit alive, says Pablo—not surprising with a fatality rate of close to 100%, at least of those who make it to the hospital. The notion of isolation itself has been hard to accept, adds David Daigle, a CDC communications officer acting as a spokesperson for the World Health Organization (WHO) in Angola. And at the outset, deceased patients were immediately zipped into plastic bags to prevent further infections, Daigle says, even though tradition requires a ritual washing of the body, during which the deceased is embraced or kissed. “People were very upset,” he says. “They couldn't grieve.”

    The result has been not just a lack of cooperation but also outright hostility—not so much in the city but in four or five of its 14 suburbs, says Brown, who was chased away by an angry mob of 40 to 50 people after a visit to a traditional chief, or soba, in one of them. “It felt pretty threatening,” he says. “The message was: Don't come back here.”

    For now, WHO and MSF are heeding that message and shunning certain areas in the hope that a broad “social mobilization” campaign will soon change attitudes. To that end, sobas, church leaders, and traditional healers are being recruited. Two medical anthropologists—one from France, the other from Burundi—are helping with this process, says Daigle.

    Some creativity is clearly needed. To replace the traditional washing ritual, the anthropologists have introduced an alternative in which family members sprinkle the dead body with bleach, says Daigle. And a popular band whose lead singer died from Marburg has recorded a song to help raise awareness; trucks mounted with loudspeakers should be blaring it out soon.

    If past experience is any guide, such measures can usually win over a population, as long as they are culturally sensitive and build on existing beliefs, says Hewlett. In recent Ebola outbreaks in Uganda and the Republic of the Congo, certain changes in burial rituals were generally accepted, such as wearing plastic gloves or introducing bleach. Simply putting bodies in plastic bags was a big mistake, Hewlett says, however well intended.

    Still, he's not surprised. Sometimes, the teams sent out to hemorrhagic fever outbreaks are a bit like “medical cowboys,” he says. “They feel very strongly about what they have to offer, especially in a crisis”—and fail to realize it may not always be appreciated.

  17. PHYSICAL ANTHROPOLOGY/PALEOANTHROPOLOGY MEETINGS

    Once-Balmy Climate Lured Humans to England Early

    1. Ann Gibbons

    MILWAUKEE, WISCONSIN—About 1200 researchers gathered near the shores of Lake Michigan here from 5 to 9 April to discuss early Englishmen, the birth of modern humans, and Stone Age weapons.

    Scientists following a trail of stone tools and butchered animal bones have uncovered evidence that early humans lived in Britain well before 500,000 years ago, perhaps not long after the first Europeans appear much farther south in Spain and Italy, about 800,000 to 1 million years ago. The early English settlers probably followed a wave of hippos, elephants, hyenas, and other animals drawn to Britain's then-balmy climate, according to a talk and poster by paleoanthropologist Chris Stringer of the Natural History Museum in London. But when the climate cooled, as it did repeatedly over the following epochs, all traces of human occupation vanished.

    Several new sites suggest that humans were in Britain well before the appearance of the 500,000-year-old Boxgrove Man, whose shinbone and teeth were discovered in a gravel quarry in Boxgrove, England, from 1993 to 1996. The sites may help shed light on whether more than one type of human migrated to Europe more than 500,000 years ago and reveal the type of terrain they could inhabit. “This pushes the age of humans north of the Alps back further than previously documented,” says paleoanthropologist Erik Trinkaus of Washington University in St. Louis, Missouri.

    Boxgrove showed that the earliest known Briton was a member of Homo heidelbergensis, a proto-Neandertal species with deep roots in Europe. The new sites have no human remains, but researchers found tools along the coast of the ancient Bytham River in East Anglia. The tools appear in some of the most ancient river terraces and are associated with insects and animals that suggest a date far older than Boxgrove, Stringer said in his talk. One site with tools may be as old as 700,000 years.

    English summer.

    Humans trailed mammals such as hyenas into England more than 500,000 years ago.

    CREDIT: JOHN SNOWBALL

    These early Europeans carried a primitive stone tool kit for scraping and cutting. But they lacked the hand ax—a versatile stone tool nicknamed the Paleolithic Swiss Army knife—already in widespread use in Africa. The Boxgrove hominid did wield a hand ax and so may have been part of a separate wave of settlers, says Stringer, who directs the $1.88 million Ancient Human Occupation of Britain program funded by the Leverhulme Trust. Studies of animal fossils paint a portrait of a warm climate that allowed animals now found only in Africa to migrate from northern Europe to England across a land bridge.

    Although humans arrived in Britain early, they did not live there continuously, said Stringer. There are no signs of human occupation during several periods, particularly during glaciations. From 180,000 to 130,000 years ago, herds of mammoth and reindeer roamed England, but there is little evidence of humans. Hippos and elephants reappear when the ice caps melt at about 130,000 years, but humans don't show up again until about 60,000 years ago when Neandertals return. Modern humans came later, but even they disappeared during an Ice Age as recent as 25,000 to 17,000 years ago. “People assume that once people were in Britain, they were always there,” says Stringer. “We're seeing little pulses of human occupation. They disappeared when it got very cold. There is not a continuous human presence until 12,000 years ago.”

  18. PHYSICAL ANTHROPOLOGY/PALEOANTHROPOLOGY MEETINGS

    Archaic Genes in Modern People?

    1. Elizabeth Culotta

    MILWAUKEE, WISCONSIN—About 1200 researchers gathered near the shores of Lake Michigan here from 5 to 9 April to discuss early Englishmen, the birth of modern humans, and Stone Age weapons.

    In the past 15 years, a flood of genetic data has helped propel the Out of Africa theory into the leading explanation of modern human origins. DNA from mitochondria (mtDNA), the Y chromosome, and ancient humans each suggest that the ancestors of all living people arose in Africa some time after 200,000 years ago, swept out of their homeland, and replaced archaic humans around the globe without mixing with them. But at a genetics symposium, two independent groups presented data from the X chromosome hinting that modern humans interbred with other human species: The teams found possible traces of archaic hominids in our genes. “Just as the Y and mtDNA data seemed to have settled it, the new data revive the question [of interbreeding],” says Stanford University's Joanna Mountain, co-organizer of the symposium. “The controversy is not settled.”

    Geneticists Makoto Shimada and Jody Hey of Rutgers University in Piscataway, New Jersey, presented an intriguing haplotype—a set of genetic mutations inherited together—that appears to have ancient roots in Asia rather than Africa. Shimada sequenced a 10.1-kilobase noncoding region in 659 individuals from around the world. Overall, the genetic variations were most frequent in Africa, just as expected if our ancestors were a subset of ancient Africans who migrated out of that continent. But one rare variant, appropriately named haplotype X, appeared in nine individuals from Europe to Oceania but was entirely absent in Africa. Shimada estimated that the haplotype arose 1 million years ago, long before the modern human exodus from Africa. “Haplotype X is difficult to explain by the recent African origins model,” says Shimada. “It's very old, it's rare, and it is widespread outside of Africa.”

    In independent work, geneticist Michael Hammer of the University of Arizona in Tucson offered a similar example. Hammer and postdoc Dan Garrigan identified a 2-million-year-old haplotype in the RRM2P4 region of the X chromosome that is common in East Asia but vanishingly rare in Africa. Their work, published 2 months ago in Molecular Biology and Evolution, raises the possibility that the haplotype arose in very ancient Asian populations, presumably of Homo erectus, an ancient human once found across Asia. “This is what you'd expect if you had introgression” between modern humans and H. erectus, Hammer said.

    But at this point several other explanations are possible. Hey of Rutgers acknowledges, for example, that haplotype X may be present in Africa but was missed by spotty sampling in that continent. “Simply observing those [examples] is not sufficient to rule out one model or another,” cautions Mountain. “What you need is 10 or 50 loci—one or two is not sufficient.” Hammer, for one, thinks that these preliminary data do “speak to some archaic admixture. The few [loci] we've done so far are so suggestive that it gives me great excitement to continue sequencing more loci.”

  19. PHYSICAL ANTHROPOLOGY/PALEOANTHROPOLOGY MEETINGS

    Modern Humans Made Their Point

    1. Ann Gibbons

    MILWAUKEE, WISCONSIN—About 1200 researchers gathered near the shores of Lake Michigan here from 5 to 9 April to discuss early Englishmen, the birth of modern humans, and Stone Age weapons.

    Long before guns gave European explorers a decisive advantage over indigenous peoples, our ancestors had their own technological innovation that allowed them to dominate the Stone Age competition: the projectile point, launched from bows or spear throwers. Paleolithic hunters shooting spears or arrows tipped with these small stone points could stay at a safe distance while hunting a wide assortment of prey—or other humans, says archaeologist John Shea of Stony Brook University in New York. Projectile launchers might even be the key to modern humans' triumph when they entered the Neandertal territory of Europe about 40,000 years ago, Shea proposed in his talk. Neandertals lacked projectiles until it was too late, and they could heft their heavier spears only as far as they could throw them. “Projectile points were such an important invention, like gunpowder, that it would have given the bearers a huge advantage,” says archaeologist Alison Brooks of George Washington University in Washington, D.C.

    The modern edge.

    Launchers shot arrows tipped with small blades (center and right).

    CREDIT: JOHN SHEA/STONY BROOK UNIVERSITY

    In two separate studies, Shea and Brooks showed that modern humans were using lightweight points associated with projectile launchers by 40,000 years ago. Shea and Brooks both think these new weapons were invented first in Africa, although they disagree about the timing. They agree that modern humans had a technological advantage when they left Africa and spread around the globe. “These lightweight points show up more than 50,000 years ago in Africa,” says Stan Ambrose of the University of Illinois, Urbana-Champaign, who heard Shea's talk. “They may have helped modern humans get out of Africa.”

    The challenge in pinpointing when projectiles were invented is that few of the launchers themselves survive, because they were made of materials that disintegrate over time. The oldest known bow is only 11,000 years old, and the oldest knownspear thrower is about 18,000 years old, but archaeologists suspect that the technology is much older. So they try to distinguish projectile points from those used on the tips of hand-thrown spears. One criterion is size: Projectile points must be small and light to soar fast enough to kill. “You wouldn't go up to a Cape buffalo with those tiny points on a thrusting spear,” says Brooks.

    Shea and Brooks each surveyed points from around the world, setting an upper limit on the size and weight of points considered projectiles. Shea set an upper limit on cross sections at the tip, whereas Brooks set a limit on weight. Shea found that projectile points were widespread by 40,000 years ago; earlier points didn't meet his criteria. He proposed that the points were developed for warfare and may have hastened the extinction of Neandertals.

    Brooks found that points from 50,000 to 90,000 years ago in three regions of Africa met her criteria. She noted that there was a “grammar and an order” to assembling these tools—one that required extensive social networks in order to exchange technology and specialized materials. She thinks that projectiles made modern humans more efficient hunters who could shoot small game and live in varied terrain. “They didn't have to kill [Neandertals],” says Brooks. “They just had to outcompete them.”

  20. PHYSICAL ANTHROPOLOGY/PALEOANTHROPOLOGY MEETINGS

    Snapshots From the Meeting

    1. Elizabeth Culotta

    MILWAUKEE, WISCONSIN—About 1200 researchers gathered near the shores of Lake Michigan here from 5 to 9 April to discuss early Englishmen, the birth of modern humans, and Stone Age weapons.

    New view of lorises. The tiny, nocturnal lorises have been considered the sloths of the primate world, creeping carefully along the shrubbery of their rainforest homes. They've also been considered a skinny branch of the primate tree, with fewer than 10 species described. But at the meeting, lorises emerged as surprisingly speedy and speciose. Anna Nekaris of Oxford Brookes University in Oxford, U.K., showed a field video of the endangered red loris scrambling around Sri Lankan trees at about 1.3 meters per second, twice as fast as captive animals. Other presenters argued that researchers have missed variation in the hard-to-track lorises: Subspecies vary in size by as much as 50%, with many differences in craniofacial proportions, says Matt Ravosa of Northwestern University Medical School in Chicago, Illinois. Jeff Schwartz of the University of Pittsburgh in Pennsylvania adds that “subspecies” differ in skull and tooth shape, too, and predicts that some will be identified as species soon.

    Speed demon.

    Once thought slow, the 130-gram red loris was filmed darting through shrubs.

    CREDITS (TOP TO BOTTOM): K. A. I. NEKARIS/OXFORD BROOKES UNIVERSITY; JOHN SHEA/STONY BROOK UNIVERSITY

    Human relations. Sarah Tishkoff and Floyd Reed of the University of Maryland, College Park, presented preliminary analyses of a massive data set on genetic variation in humans around the world, particularly Africans. Samples from more than 3000 people, including 2000 Africans, were processed at 1275 loci by a genotyping powerhouse, the Marshfield Clinic Research Foundation in Wisconsin. Tishkoff and Reed, who received the complete data set only 3 weeks ago, say it offers a powerful tool to uncover relationships among populations. For example, the data suggest that culturally distinct groups of Pygmies are more closely related to each other than to other Africans. The researchers also detected unique similarities in the peoples of Oceania and East Africa, lending support to the hypothesis of an early “southern route” of migration out of Africa, around the coast of India to Oceania and then Australia. Finally, they found ancient kinship among three groups of click speakers, supporting the idea that the click languages form a single, ancient language family (Science, 27 February 2004, p. 1319).

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