News this Week

Science  27 Oct 2006:
Vol. 314, Issue 5799, pp. 574

You are currently viewing the .

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


    Lucy's Tour Abroad Sparks Protests

    1. Ann Gibbons

    The famous human ancestor Lucy probably lived and died within a short distance of her burying ground at Hadar, Ethiopia, after a short, obscure life. Now, 3.1 million years after her death, Lucy is headed for her first public appearance ever at a museum in Texas, where her status as a paleo-rock star is expected to draw large crowds. After 4 years of talks, officials signed a multimillion-dollar contract Tuesday to fly the original partial skeleton to the Houston Museum of Natural Science for an exhibit in fall 2007, says museum archaeologist Dirk Van Tuerenhout.

    Jet set.

    Museums now display mounted casts of Lucy, but the original relics (inset) are to be flown to a museum in Houston, Texas, and perhaps others.


    Ethiopian officials have high hopes that Lucy will do for Ethiopia what King Tut's riches did for Egypt. “It will put Ethiopia on the map as the cradle of mankind and of civilization,” says Mohamoud Dirir, Ethiopia's minister of culture and tourism. The culture ministry is planning a lengthy tour for Lucy, with stops at 10 museums and a homecoming in 2013.

    But many of the people who know Lucy best—leading researchers in the United States and Africa—are fighting to stop her posthumous tour, saying that transporting and exhibiting the fragile, one-of-a-kind specimen could damage it. They have protested to African politicians and American museum officials that Lucy's travels are unlikely to benefit Ethiopian science, and that the exhibit would violate a 1998 UNESCO agreement against transporting original hominids out of their home countries. Such concerns have prompted several leading museums to turn down the exhibit. “There is only one Lucy,” says Bruce Latimer, director of the Cleveland Museum of Natural History in Ohio. “If something should happen to her, she's irreplaceable.”

    They are not concerned only about Lucy. Her travels may pave the way for other rare hominids to journey overseas. For example, Kenyan officials are in discussions with the Field Museum in Chicago, Illinois, about exhibiting the 1.6-million-year-old Nariokotome Boy, the only published skeleton of Homo erectus. Lucy's tour “will start an avalanche,” grimly predicts paleoanthropologist Clark Howell of the University of California, Berkeley. “We'll fight this thing when it appears on opening day and afterward.”

    Many museums already feature Lucy, a key ancestor whose bones first revealed that our lineage walked upright before evolving a big brain. But all exhibits use casts: The original fossils have never been on display. They have been out of Ethiopia only once before, in 1975, when discoverer Donald Johanson took them to the Cleveland Museum for study and baptized Lucy as a new species, Australopithecus afarensis.

    Johanson returned the bones to Ethiopia in 1980. At that time, African nations were reclaiming fossils that had been shipped around the world and making them centerpieces of museums and fledgling research programs. Keeping original fossils in Africa was part of a strategy for boosting homegrown science. “If we start sending these fossils out of the country, Kenya and Ethiopia cease to be places where you can study fossils. It immediately changes the role of the museum as a place for scientific study,” says Kenyan paleoanthropologist Richard Leakey, former director of the National Museums of Kenya. Paleoanthropologist Bernard Wood of George Washington University in Washington, D.C., puts it more starkly: Without the fossils, “why would anybody want to [work in] Ethiopia or Kenya? Why would anybody want to develop the science base or train the people?”

    That's part of the reason why, in 1998, three dozen scientists from 23 nations signed an international agreement not to transport original hominid fossils from their homelands except for compelling scientific reasons. Now, however, persistent economic woes have prompted government officials in Ethiopia and Kenya to revisit the idea. Ethiopian officials say that spreading the word about Lucy and their nation's rich cultural heritage can help draw tourists to Ethiopia and change its image. “The money will go to museums, and just to museums,” says Dirir. “Just keeping fossils in Ethiopia will not develop science, museums, or the custodians of these fossils.”

    Houston plans an exhibit that will include an overview of Ethiopian history from 5 million years to the present. Van Tuerenhout asked for other, unpublished fossils, including those of the even older hominid Ardipithecus, but Dirir said those will not go.

    It is Lucy, however, whose box-office appeal is critical for the Houston exhibit's success, Van Tuerenhout says: “Lucy has name recognition. That is especially important with schoolchildren. You can show them this is what evolution is about.”

    John Kappelman of the University of Texas, Austin, who is developing teaching materials on Lucy for children and plans to do state-of-the-art computed tomography scans of the fossils, predicts that if the show travels to other venues, “millions of Americans will look at this original material. That could change the way many people think about human evolution,” including helping to defeat creationism.

    To draw in the masses, Van Tuerenhout and Kappelman say they need the original fossil. They point out that few crowds would line up to see replicas of the Mona Lisa or the Hope diamond, for example. That's why security for Lucy will need to be as good as it is for the genuine Hope diamond, with guards, insurance, and trained handlers, responds Richard Potts of the Smithsonian Institution. He agrees with the UNESCO policy, saying that extended exhibition is not worth the risk unless the bones need to be moved for compelling research purposes.

    Building boom.

    The new building at the National Museum of Ethiopia is scheduled to open in 2007, while Lucy is abroad.

    Van Tuerenhout says Houston will provide whatever security measures the Ethiopian ministers seek; the ministers are dictating those details, he says, from Lucy's first-class seat on Ethiopian Airlines to the fossils and artifacts that accompany her.

    Houston is to be the first stop on a longer tour to musums in New York, Chicago, and Washington, D.C. But none of those museums have plans to sign on as yet, and the Smithsonian and the Cleveland Museum have explicitly said no. The nonprofit Leakey Foundation, which funds anthropological research, considered sponsoring the exhibit but decided against it last year after passionate protest from its scientific executive committee, says Leakey Trustee Don Dana, a vice president of Wells Fargo Bank. Some trustees also were concerned because the Houston Museum would not divulge details of its financial arrangements with Ethiopia. “You want to avoid a situation where you're buying someone a Land Rover,” says Dana.

    Ethiopian scientists say it's not yet clear to them where the loan fees from Lucy will go. “What Ethiopians are benefiting from this?” asks Ethiopian paleoanthropologist Zeresenay Alemseged of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “I have not seen a document that clearly defines the role for the National Museum of Ethiopia. I have never heard of any Ethiopian paleoanthropologist being involved. If money is being generated, it should be clear what percentage will go to Ethiopian science.”

    Houston officials bristle at the suggestion that they tell Ethiopian ministry officials how to spend their money, but other museums do restrict the use of loan fees. For example, National Geographic Society Vice President Terry Garcia says that he explicitly required that fees paid to Egypt for the new King Tut exhibit be used to advance archaeology.

    Lucy's impending visit is a test case that has “started a conversation at museums,” says paleontologist Neil Shubin, provost of the Field Museum. After a visit to the Field in September, Kenyan officials surprised museum officials with an announcement that fossil hominids, including the Nariokotome Boy, would be exhibited there, says Shubin. “We had not even vetted the idea with our board,” he says; he was immediately lobbied by prominent scientists opposed to the idea.

    Shubin says talks are preliminary, but the director general of the National Museums of Kenya, Idle Omar Farah, is optimistic: “Our initial verbal conversations appear to indicate that we could have some selected collections of our hominid fossils traveling to the Field Museum, but the form, composition, and time is as yet to be determined.” Farah says loan fees would be used to set up an endowment for the museum, and the interest would be spent on collections and staff. He has had inquiries from Germany, Switzerland, the United Kingdom, and Japan, if the Field passes.

    Kenyan paleontologists, however, oppose such displays. “I do not support displaying of our precious fossils in any [other] museum regardless of what funds it would attract,” says Emma Mbua, head of paleontology at the National Museums of Kenya. “These fossils are our pride and strength as a country. Displaying them anywhere else than our own museum is not right.”

    Meanwhile, both Kenya and Ethiopia are rebuilding their museums. Ethiopia's National Museum is getting a new, five-story building scheduled to have its grand opening in 2007—when its star attraction is out of town.


    Higher Costs, Accident Imperil Plans

    1. Jeffrey Mervis

    The Integrated Ocean Drilling Program (IODP) has hit rough waters. A spike in the demand for oil-drilling equipment and services has added 20% to the cost of a planned extreme makeover of the program's former workhorse, the drill ship JOIDES Resolution (Science, 23 December 2005, p. 1890). By happenstance, the funding squeeze comes as the program's future flagship, the new Japanese drilling ship Chikyu, sustained damage to one of its key drilling components during a shakedown cruise off the Japanese coast. “It's tough going at the moment,” admits Bill Ball of the Joint Oceanographic Institutions, which is managing the modernization of the JOIDES Resolution for the U.S. National Science Foundation (NSF).

    IODP's predecessor, the Ocean Drilling Program, was for 2 decades the world's premier effort to explore beneath the sea floor (Science, 18 April 2003, p. 410). In 2003, the U.S., European, and Japanese members of the consortium reorganized the program and began preparing for the arrival of the $550 million Chikyu, which is equipped with a second pipe, called a riser, that allows it to drill deeper holes and in areas near oil and gas deposits (Science, 11 March 2005, p. 1552). Both the Chikyu and the renovated ship, which NSF leases from an oil-drilling company, were to begin scientific drilling in the fall of 2007.

    That schedule now appears impossible to meet for the refurbished ship. For $115 million the NSF vessel, which will be renamed, was to get a 30-foot hull extension that provides 50% more lab space and bigger and better accommodations. The ship is also slated for enhanced instrumentation and drill capacity and faster, more fuel-efficient operations. Now NSF officials must figure out how to either get the most for the budgeted amount or pay for the $25 million overrun by cutting back on another big-ticket construction item. “Any increase has to come from the major research equipment and facilities account, not from the research account,” explains Margaret Leinen, head of NSF's geosciences directorate.

    The clock is ticking as NSF awaits a report on how much can be done to improve the ship's capabilities without stretching the hull. The renovations were supposed to have gotten under way this month at a facility in Singapore, and NSF is paying tens of thousands of dollars each day the ship is tied up. Although work can begin on improvements unrelated to the extension, Leinen stresses that NSF must make a decision “as soon as possible.” In the meantime, she says “we definitely won't be making” the target date of November 2007 to resume operations.

    Still standing.

    The crew of the Chikyu hopes to repair a storm-damaged part of its drilling equipment while at sea.


    As for the Chikyu, officials at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) are hoping to fabricate or buy a replacement for a rod that's part of a device to prevent blowouts when the ship drills into a volatile formation. It got bent when the ship was caught in a sudden storm earlier this month with its drilling equipment deployed. Asahiko Taira, director-general of JAMSTEC's Center for Deep-Earth Exploration, says the damage is minor and the bent rod will be replaced at sea.

    The Chikyu must then rush off to drill for oil off the coast of eastern Africa. Taira says the commercial job will allow the agency to meet rising operating costs while still training the crew and gaining drilling experience in various geologic environments. “We will have this ship ready for scientific drilling in September next year,” he vows.


    Honey Bee Genome Illuminates Insect Evolution and Social Behavior

    1. Elizabeth Pennisi

    Four years in the making, the 236-million-base genome of the European honey bee, Apis mellifera, proved tough to decipher. But the hard work paid off this week as 170 researchers rolled out their analysis of this fifth insect sequenced to date. “To have [this] genome laid out in some detail is a real step forward for our understanding of this part of the animal kingdom,” says Francis Collins, director of the National Human Genome Research Institute in Bethesda, Maryland, which funded the sequencing work.

    The honey bee genome, described in the 26 October issue of Nature, has inspired dozens of recent papers in several journals, including three this week in Science. The 10,157 genes identified so far contain clues about the social behavior, physiology, and evolution of the honey bee, as well as insights into other insects and even vertebrates. The sequence also promises to illuminate the genetic and neural basis of animal social behavior. “It's the understanding of behavior that's going to be the big payoff [of the honey bee genome],” predicts George Weinstock, the geneticist at Baylor College of Medicine in Houston, Texas, who led the sequencing effort.

    Bee hives are organized around an egglaying queen tended by workers who, during their lifetime, make the transition from hive-bound duties, such as nursing larvae, to more far-ranging jobs such as foraging for food or defending the nest. With just a million neurons, the bee brain is relatively simple, yet these insects are sophisticated—for example, they use highly choreographed “dances” to communicate the location of nectar-laden flowers.

    With the aid of the genome data, Gene Robinson, a neurobiologist at the University of Illinois, Urbana-Champaign (UIUC), has begun to tease apart the genetic and environmental components of the bee social structure and its related behaviors (Science, 10 October 2003, p. 296). Now, working with Charles Whitfield, a geneticist also at UIUC, Robinson has used microarrays to determine which of 5500 genes are active in young bees and which are affected by age-related changes in juvenile hormone, a key mediator of behavioral maturation. Those results appeared online 26 October in the Proceedings of the National Academy of Sciences (PNAS).

    Two other studies, one reported in the same PNAS issue and another in Science, begin to address what turns the bee's behavioral genes on and off. On page 647, Robinson's UIUC colleague Saurabh Sinha has picked out some of the regulatory regions that control some 3219 genes in the bee's brain, including ones important for the development of foraging behavior. And on page 645, Ying Wang in Robinson's lab and their colleagues report that unlike other insects studied, the honey bee has a vertebrate-like set of enzymes needed to methylate genes, implying that methylation may be important in silencing genes in bees as well as in vertebrates, including humans. “For people interested in human behavior, their interest [in the honey bee] has just gotten supercharged,” says Collins.

    Minding the hive.

    The social nature of honey bees, with workers that tend larvae and an egg-laying queen, makes the species' genome alluring.


    Meanwhile, evolutionary biologists are keen to compare the honey bee genome to those of the six-legged lab rat of the insect world—the fruit fly—the mosquito, and the silkworm. “We are poised to sketch out the beginnings of genomic evolution in the insects, a not-trivial slice of the diversity of life,” says Brian Farrell, a Harvard entomologist at the Museum of Comparative Zoology in Cambridge, Massachusetts. Moreover, a new bee fossil found in 100-million-year-old amber, reported on page 614, should clarify how honey bees evolved from predatory wasps and became key pollinators. The fossil, and the pollen captured with it, are “enabling us to place a time frame on this genomic evolution,” Farrell adds.

    These new genomic analyses suggest that bees and their wasp relatives, the so-called Hymenoptera, had an earlier-than-expected evolutionary start. In one study, Joél Savard and Martin Lercher of the University of Cologne, Germany, and colleagues compared 185 genes from the honey bee, fruit fly, mosquito, flour beetle, parasitic wasp, and silkworm. They concluded that the Hymenoptera branched off quite early from the line of so-called holometabolous insects, those that undergo complete metamorphosis. This wasp-bee branch predates that of the beetles, contrary to prevailing dogma, Savard and Lercher argue in the November issue of Genome Research.

    Genomics studies are tracing the roots of bees in general, and honey bees in particular, to Africa. In one, published in the 6 October issue of PNAS, bee systematist Bryan Danforth of Cornell University published a new family tree for bees, which are 16,000 species strong. He not only analyzed morphological data but also used five genes from the honey bee genome as a way to track down those same genes in 80 bee species and 14 wasps. The primitive bee lineages are most diverse in Africa, indicating that's where this group likely arose, he concludes.

    In the other study, Whitfield sorted out the radiation of the relatively late-evolving honey bees. Although Harvard entomologist Edward Wilson suggested 35 years ago that the honey bee first called Africa home, most researchers had concluded that this insect hails from Asia, as that's where the rest of the Apis genus is found. By analyzing 1500 single-nucleotide polymorphisms (SNPs)—differences of a single DNA base—Whitfield and his colleagues confirmed that four clusters of honey bee subspecies, as originally defined through mitochondrial DNA studies, exist: two in Europe, one in Asia, and one in Africa. (Subsequently, there have been multiple introductions of various subspecies by humans into the New World.)

    The SNP data reveal how these clusters arose from two “out of Africa” migrations, Whitfield and his colleagues report on page 642. In one, bees landing in Spain moved into central Europe and Russia. In another, bees colonized eastern Europe south of the Alps and then expanded into Asia. As a result, despite their geographic proximity, “the two European groups are the most different on Earth,” says Whitfield.

    Systematics shuffle.

    The sequenced genomes of all the insects pictured are finished, planned, or under way, and already, genomic studies have shifted wasps and bees to predate beetles.


    Compared to the fruit fly and the mosquito, the honey bee has evolved at a glacial pace, Weinstock and colleagues report in the 26 October Nature paper. But compared to those two insects, certain gene families essential to the bee's social lifestyle have expanded in size. In the November issue of Genome Research, Hugh Robertson and Kevin Wanner of UIUC report about 165 odorant-receptor genes in the honey bee genome, more than double what Drosophila and Anopheles have. This expansion makes sense, says Robertson, given the bee's need to recognize kin and find suitable flowers. Honey bees also have multiple versions of a pigmentation gene, called yellow protein, that have been co-opted to make royal jelly, a nutrient-rich secretion that causes larvae to develop into queens, Ryszard Maleszka of Australian National University in Canberra and his group report in the same issue of Genome Research.

    In a few respects, the honey bee shares more similarities with humans than with the other insects whose genomes have been sequenced. It retains some 700 genes found in other organisms, such as nematodes, yeast, or mammals, that the fruit fly and mosquito have lost. Those genes are presumably ancient, found in the common ancestor of all the creatures and then lost in a few lines. Take some of the genes that drive the biological clock behind circadian rhythms. The honey bee has several clock genes that closely resemble mammalian clock genes yet are missing in fruit flies, says Guy Bloch of The Hebrew University of Jerusalem, Israel. At the same time, the honey bee lacks two of the fruit fly's clock genes, says Bloch. Drosophila apparently grew to depend on one subset of an ancient cluster of clock genes, whereas bees and mammals depend on another.

    Dozens of other findings have come out of this first round of exploration into the honey bee genome, says Weinstock. Still, he's most excited about the long-term effect of this massive endeavor. “It's very gratifying to see the biology coming alive right away. [But] it's more than just teasing the biology out,” Weinstock says. “It's getting the whole community up to speed in genomics.”


    Dark-Horse Neutron Source Heads Belatedly Toward Starting Line

    1. Daniel Clery

    Several European governments are lining up behind construction of a high-powered neutron source that would allow the region to keep pace with new facilities in the United States and Japan. The design team for the €1.2 billion ($1.5 billion) European Spallation Source (ESS) was dissolved in 2002 due to lack of interest from potential funders, but supporters point to several recent studies backing the concept for the renewed interest. “There is now a total consensus that the ESS is necessary,” says Peter Tindemans, chair of the ESS Initiative, a lobbying group that has been keeping the ESS flame alive.

    Big draw.

    Thousands of researchers want the European Spallation Source, but will politics behind closed doors decide its location?


    Neutron beams are used in a wide variety of disciplines, including physics, materials science, biochemistry, engineering, and medicine. Because neutrons lack electrical charge, they can penetrate deep into materials to reveal structure that is invisible to other probes. Some 5000 researchers in Europe use neutron sources, which come in two types: nuclear reactors and spallation sources, accelerators that fire a proton beam at a metal target to create a spray of neutrons. For more than a decade, Europe has been home to both the world's most powerful nuclear reactor source, the Institut Laue-Langevin in Grenoble, France, and the top spallation facility, ISIS, at the United Kingdom's Rutherford Appleton Laboratory near Oxford.

    In 1999, the Organisation for Economic Co-operation and Development (OECD) in Paris published an influential report on neutron sources, which recommended that East Asia, Europe, and North America should each build a new high-powered source. The report galvanized efforts for new sources in the United States and Japan. Earlier this year, the Spallation Neutron Source at Oak Ridge National Laboratory in Tennessee produced its first neutrons and is now working up to its full beam power of 1 megawatt. And Japan is building a spallation source as part of its J-PARC proton accelerator complex at Tokai. The 1-megawatt source will produce its first beams in 2007.

    European governments, meanwhile, eschewed new construction. It wasn't for lack of scientific interest: A group of European labs had begun design work on ESS in the early 1990s, and in 2002, researchers put forward a final project proposal for a 5-megawatt machine. Five regions expressed interest in hosting it. But with no national governments prepared to foot the bill, the idea languished.

    Since then, “there's been a lot of work going on behind the scenes,” says physicist Robert Cywinski of Leeds University in the U.K., scientific adviser to an ESS bid from three Yorkshire universities and the regional development organization. In 2003, the Yorkshire team met with U.K. Science Minister David Sainsbury, who ordered up a review of Britain's future requirements for neutron facilities. Published last March, the review didn't endorse ESS but made a megawatt-level spallation source the top priority and urged the government to work with European partners to develop one.

    ESS is also one of 35 large-scale projects deemed worthy of support in a report this month from the European Strategy Forum on Research Infrastructures (ESFRI) (Science, 20 October, p. 399). ESS could move straight to construction as soon as negotiations on site and funding are complete, the forum concluded. “The ESS has come back with a vengeance in the ESFRI road map,” says Cywinski. Tindemans says that both the U.K. neutron review and the road map have “helped enormously.”

    Physicist Karl-Fredrik Berggren of Linkopings University in Sweden says that the Swedish government last year completed a review and supports building ESS at Lund University. “We expect approval should come fairly shortly,” he predicts. At a meeting of the ESS Initiative in Bilbao, Spain, earlier this month, the Basque regional government said the national government would support its bid, along with a rumored €300 million in funding. Tindemans says Hungary is also poised to approve a bid to site ESS on its soil.

    Cywinski says the Yorkshire bid is currently in limbo, as the government has not responded to the neutron review. Right now, “governments are just trying to form alliances,” says Tindeman. According to Berggren, “The country that ties up the big nations very quickly will win.”

    With the U.S. and Japanese sources already talking about upgrading the power of their accelerators, to 2.5 and 5 megawatts, respectively, Europe needs to move quickly if it is to keep pace, says Cywinski: “If the focus of neutron science moves from Europe, the scientists will move too.”


    DeCODE Adds Plagiarism Allegation to Its Case

    1. Eliot Marshall

    Escalating its pursuit of employees who allegedly took trade secrets when they quit, deCODE Genetics in Reykjavik, Iceland, has now accused its former vice president, Hákon Hákonarson, of plagiarism. Hákonarson is one of five former deCODE researchers whom the company sued last month for taking confidential data to set up a competing genetics unit at the Children's Hospital of Philadelphia (CHOP) in Pennsylvania (Science, 6 October, p. 30).

    Hákonarson, director of the new unit, declined comment to Science. But CHOP President Steve Altschuler said in a statement: “DeCODE's claims of research misconduct, like the complaint it filed in federal court against Dr. Hákonarson, are wholly baseless and without merit.”

    DeCODE makes the new allegations in an 18 October letter to the National Institutes of Health (NIH) and the Office of Research Integrity (ORI) at the U.S. Department of Health and Human Services. The five-page letter, signed by deCODE counsel Thorir Haraldsson and Hreinn Stefánsson, head of the company's central nervous system diseases division, asks U.S. officials to investigate “research misconduct … and take appropriate action.” ORI could bar Hákonarson and, in theory, CHOP from receiving U.S. research funds if the charges are found to be true.

    Using a document previously filed with the Philadelphia federal court hearing its lawsuit, deCODE's new letter supports its plagiarism case with a side-by-side comparison of texts taken from a 2005 grant application it submitted to the European Union for schizophrenia research and a CHOP proposal for asthma studies, which deCODE claims Hákonarson and CHOP authored and submitted to NIH in April 2006. The comparison highlights more than a dozen passages that are nearly identical. DeCODE charges: “The CHOP grant application contains text taken verbatim from the description … in the deCODE grant proposal.” DeCODE also claims that Hákonarson misstated his company credentials in the NIH grant.

    In the lawsuit revealed last month, deCODE asked the federal court to prevent its former employees from working with CHOP on its new genetics unit for 2 years. The company claims that Hákonarson and his colleagues downloaded thousands of files from deCODE onto portable hard disks and memory sticks, copied them, and then destroyed some of the equipment to hide evidence. The court has not yet reached a decision on deCODE's request for an injunction. The hearing was suspended earlier this month and is expected to resume on 13 November.


    Scientists Urge Libya to Free Medics

    1. John Bohannon

    U.S. scientists are adding their voices to mounting international pressure on Libya to release six foreign medical workers who could face execution within weeks. A letter published online this week by Science—written by virologist Robert Gallo, director of the Institute of Human Virology in Baltimore, Maryland, and co-discoverer of HIV, and signed by 43 other scientists—accuses the Libyan government of using the medics as scapegoats for the accidental infection with HIV of more than 400 children at a hospital in Benghazi. Libyan police rounded up the five Bulgarian nurses and a Palestinian doctor in 1999 and used torture to extract confessions that they had deliberately infected the children as an act of bioterrorism, according to human rights organizations. European scientists say poor hygiene likely caused the outbreak before the medics started working in the country (Science, 8 April 2005, p. 184).


    A Libyan judge sentenced six foreign medical workers (behind bars, below) to death, but scientists say they are innocent and that the Libyan children (above) were accidentally infected with HIV before the medics arrived.


    The scientific evidence supported the medics' innocence, says Vittorio Colizzi, a virologist at the University of Rome “Tor Vergata” and an expert witness in the case. But it was disregarded by a Benghazi judge in 2004 in favor of damning testimony by Libyan doctors that was “full of errors and misunderstandings of basic molecular biology.” The judge sentenced the medics to death by firing squad. The medics' final appeal is now being heard by the Libyan supreme court in Tripoli. Yet more scientific evidence has accumulated since then, says Colizzi, but the supreme court denied the defense an opportunity to present it. The final session is scheduled for 31 October; a verdict is expected soon after.

    “We want to get people angry and influence their governments to do something,” says Gallo. Libya's actions “send a chilling message” to international health workers that could discourage them from working in the developing world, says Gallo, adding that the Libyans themselves “need all the scientific help they can get to prevent another outbreak.” For its part, the Libyan government has said that the case could be settled if Western governments pay “blood money” to satisfy the families of the infected children; a sum of $5.7 billion has been suggested.

    Outrage among scientists has been building in recent weeks in parallel with diplomatic pressure from the U.S. and European governments. The U.K.'s Royal Society, the New York Academy of Sciences, and the Federation of the European Academies of Medicine, among others, have published open letters to the Libyan government calling for the medics' release. The Web site of AAAS (publisher of Science) contains directions for how individual scientists can add to the pressure.*

    If the medics are not given a reprieve, says Gallo, “I will do everything I possibly can, starting with a call for an emergency session of the [U.S.] Academies of Science” to consider a “full scientific embargo.” And if Libya decides to free the medics, Gallo says international praise and support should be equally swift: “They need to know that this virus is a problem for all of us, and we scientists can help.”

    • *


    Restoring Yosemite's Twin

    1. Erik Stokstad

    Environmentalists have mounted a campaign to pull down a dam that drowned the scenic Hetch Hetchy Valley. Scientists say it would be a grand experiment in restoration

    The way back.

    Historic photos could provide a guide to restoring the valley.


    “It is a wonderfully exact counterpart of the Merced Yosemite, not only in its sublime rocks and waterfalls but in the gardens, groves and meadows of its flowery park-like floor.”—John Muir

    John Muir suffered his greatest defeat in 1913, when President Woodrow Wilson signed a bill authorizing the building of a dam in the naturalist's beloved Yosemite National Park. Muir had fought the proposal for a decade, but he and his supporters proved no match for San Francisco's growing thirst. The 100-meter-tall O'Shaughnessy Dam provided the city with a reliable, gravity-fed supply of water so clean that it still needs no filtration. The environmental cost was steep, however: The dam flooded Hetch Hetchy Valley, famed for its striking granite cliffs and waterfalls that rivaled its twin, Yosemite Valley, for grandeur.

    Ever since, environmentalists have dreamed of undoing what they see as one of the greatest environmental sacrileges of the past century. Tearing down the dam and restoring the valley would “inspire people to replicate that restoration across the state, throughout the country, and around the world,” says Spreck Rosekrans, an analyst at Environmental Defense in Oakland, California. Scientists view it as an unprecedented chance to study the ecological benefits of dam removal. “It's a huge opportunity to advance restoration science,” says David Hart, an environmental scientist at the University of Maine, Orono.

    It would also be a mammoth undertaking. No dam this size has ever been removed—the tallest is 20 meters. “The scale is fundamentally different,” says Emily Stanley of the University of Wisconsin, Madison, who has studied smaller dams. With more than 500,000 cubic meters of concrete to demolish and truck out, and 825 hectares of valley floor that will emerge from the receding water like a moonscape, advocates and skeptics agree that the idea is uncharted territory.

    Combine those uncertainties with the huge economic cost and California's legendary water politics, and it's clearly an uphill battle. But advocates say the proposal is gathering steam, and it did get a boost this summer when a state analysis concluded that it was technically feasible. “It's such a grand idea, an extraordinary idea, that it merits further study,” said state assemblywoman Lois Wolk, who called for the report at a hearing in Sacramento this month.

    Dam in the valley

    This isn't the first time that someone has proposed restoring Hetch Hetchy. In 1987, an unlikely advocate emerged: Don Hodel, secretary of the interior during the Reagan Administration. During a visit to Yosemite National Park, he heard complaints about the crowding in Yosemite Valley and was floored to learn that a similar valley, Hetch Hetchy, had been turned into a reservoir. He has been championing its restoration ever since. “The U.S. pushes countries to develop national parks around the world, and we've got a dam in a national park. It's absolutely ridiculous,” says Hodel, who now runs an energy consulting firm in Colorado.

    But Hodel's attempt in the 1980s didn't go far. “I spoke with [Diane] Feinstein”—then mayor of San Francisco—“and she went ballistic,” says Hodel. According to Hodel, Feinstein persuaded Congress to put language in the Interior appropriations bill that prohibited the agency from spending any money to further examine the idea. “We were totally stymied,” Hodel says.

    Feinstein maintained that Hetch Hetchy provides irreplaceable water storage for the city and keeps costs down. And the dam continues to generate 400 megawatts of green hydropower—now worth about $50 million a year. The state is not keen to lose those benefits. “San Francisco and the Bay Area are very concerned about these proposals,” testified Michael Carlin, assistant general manager for water for the San Francisco Public Utilities Commission at the state hearing this month.

    After Hodel's initial attempts were squashed, the proposal dropped off the radar screen for about a decade. It began to resurface in 1999, when environmental activist Ron Good and others founded Restore Hetch Hetchy, a small advocacy group in Sonora, California. Not long after, legendary environmentalist David Brower helped enlist the support of Environmental Defense, which has made the proposal a high priority.

    The first feasibility issue was water storage: Could San Francisco get by without the dam? Environmental Defense's Rosekrans tackled the question using a computer model, concluding in a 2004 report that “a few straightforward plumbing fixes” could solve the storage issue, he says. His solution was to connect the Hetch Hetchy aqueduct—which takes water to San Francisco—to Don Pedro Reservoir, 56 kilometers downriver from the Hetch Hetchy Dam (see map); this would provide storage for more than the annual flow of the river.

    Jay Lund, a civil engineer at the University of California (UC), Davis, has independently hit on the same engineering fix. “It provides unusually reliable storage relative to demand,” Lund says. “There's still a lot of reliability even if you get rid of Hetch Hetchy.” And that will remain true despite projected population growth and climate change, he and grad student Sarah Null show in a paper in the Journal of the American Water Resources Association published in April.

    Although these findings are accepted by the scientific community, they “poke common wisdom in the eye,” says fluvial geomorphologist Jeffrey Mount of UC Davis, so politicians remain wary. Everyone does agree that the costs of this replumbing and dam removal would be huge. Estimates vary from $1 billion over several years from Restore Hetch Hetchy to $3 billion to $10 billion from the state's Department of Water Resources. That's a bundle for a state that's already spent nearly $2 billion trying to fix its bay delta, for example.

    Simple fix.

    Two studies concluded that San Francisco's water supply could be ensured by linking the Don Pedro Reservoir to the Hetch Hetchy aqueduct.


    Hodel thinks up to $1 billion could be saved by draining the water but leaving the dam in place; the concrete hulk would be a memorial to errant ways of the past. “People would find it fascinating to look at the dam, and they would say: ‘Can you believe they put a dam in this beautiful valley?’”

    At any rate, advocates for restoring Hetch Hetchy say the state shouldn't have to foot the entire bill, as the reclaimed valley would be national treasure. “All Americans have a stake in the outcome of the discussion,” Good says.

    A blank slate

    But transforming the existing reservoir into the beautiful valley Hodel and others envision will not be easy. The goal is to restore 825 hectares that are now underwater with an array of habitats—wetlands, grasslands, oak savanna, and pine forest—essentially from a blank slate, says restoration ecologist Mark Cederborg of Hanford Applied Restoration and Conservation in Sonoma, who consults for Restore Hetch Hetchy.


    Once-submerged rock, seen here during a drought, will need to regrow lichens.


    Figuring out exactly what to do will require some detective work. The reference, Yosemite Valley, has been heavily altered by invasive species, fire suppression, and other changes, so researchers will have to pore over historic photographs to help envision the predam landscape. Logistics will likely be difficult, too. The valley doesn't have roads and is surrounded by designated wilderness area, so workers may not be able to use heavy mechanical equipment. Herbicides use could be ruled out as well, because the river water will still be headed for city faucets.

    The best approach would be to slowly lower the reservoir and restore the emerging land in stages over a number of years, says Joy Zedler, a wetlands ecologist at the University of Wisconsin, Madison, who in 2004 created an adaptive restoration plan for the valley with her graduate students. Zedler maintains that such a phased approach would enable researchers to study how well restoration techniques were working and modify them before the next stage. “You'd be wiser before you exposed more of the bottom,” Zedler says. It would also spread out and lower costs, by improving techniques, and be easier on existing wildlife, she says.

    This strategy, for instance, would reveal early on which invasive species are likely to be a problem—more than 140 thrive in Yosemite National Park—without letting them run wild over the whole valley. Invasives are a concern because the exposed terrain would be “like a vacant lot for plants to colonize,” says Hart. Unlike most other restoration projects, this one would have a failsafe mechanism to deal with runaway invasives, Zedler adds: raise the water level and drown them.

    Restoring the lichens that once gave the rock its distinctive color will be especially daunting. Because the lichens died when they were submerged, the exposed rock will appear bleached—a 100-meter-tall “bathtub ring”—after the water is lowered. A 1988 Park Service report estimated that it would take 80 to 120 years for the lichens to grow back on their own. Zedler proposes experiments to speed the recovery by propagating native lichens and testing various agents to help them adhere when sprayed onto barren rock.

    Even with such experiments, no one can say for sure how the ecosystem is likely to respond. “If people think it will be pristine, they may be surprised,” Stanley says. “It may end up creating a novel ecosystem that we haven't seen before.”

    Weighing priorities

    The Hetch Hetchy experiment is not likely to happen anytime soon, even advocates concede. Only a few members of the state legislature are gingerly probing the issue, and opposition from Feinstein, who is now a U.S. senator, could hinder federal participation. “Politically right now, I don't see the stars aligned,” says Mount.

    The key reason: “The level of distrust among the various actors is very, very high,” Dean Misczynski, director of the California Research Bureau, testified at the Sacramento hearing. The bureau has recommended appointing a blue-ribbon panel, with advisory groups of stakeholders and technical experts, to lay out ways to keep all the current beneficiaries of the dam from feeling they are getting a raw deal.

    Aerial approach.

    Working without roads, crews may have to plant seeds and control erosion via helicopters.


    Hodel remains upbeat about the long view. “It is inevitable that the dam will be removed,” he says, adding that the biggest opposition to the project now is economic, not technical. “It's only a matter of time and negotiations.”

    But others point out that there are more pressing ecological needs. The habitat in Yosemite National Park is less endangered than other places, like southern California, where nature is being boxed in by development. Margaret Palmer of the University of Maryland, College Park, questions the wisdom of investing huge sums in fixing a short stretch of river in a relatively unblemished watershed. “The priority needs to be cleaning up our damaged streams, many in urban and agricultural areas,” she says.

    Still, many acknowledge the validity of the central argument. “That land was set aside for the purpose of preserving it as wilderness,” says civil engineer William Graf of the University of South Carolina, Columbia, who studies dam removal. “We have not carried through on the promise.” Muir, who died a year after Wilson approved the dam, would heartily agree.


    Big Dams Ready for Teardown

    1. Erik Stokstad

    As advocates push for the removal of O'Shaughnessy Dam in Yosemite National Park (see main text), they'll be closely watching a $185 million restoration project in Olympic National Park in Washington state. There, two dams on the Elwha River are slated to be demolished starting in 2009. “If it works well, it will open the door to removing large dams like Hetch Hetchy,” says Emily Stanley of the University of Wisconsin, Madison. “I see it as the test case for very large dam removal.”

    Cross section.

    O'Shaughnessy Dam in Hetch Hetchy Valley holds more water and has more concrete than the two Elwha River dams, but it has trapped less sediment.


    The Elwha once boasted an estimated 400,000 spawning sockeye salmon and other fishes. But the Elwha Dam and Glines Canyon Dam, which were built in 1913 and 1927, respectively, to provide hydropower for a mill in the town of Port Angeles, cut off 112 kilometers of spawning runs and degraded the quality of the remaining 8 kilometers.

    It took decades of legal wrangling to get a green light for the dams' removal. In 2000, after the Elwha Klallam Tribe and various environmental groups prevailed, Congress appropriated $29.5 million for the Department of the Interior to buy the dams. In an effort to restore the salmon runs, Congress has so far approved $17 million of $48 million for tearing down the dams and replanting the river valley. (The $185 million price tag also includes $75 million to provide a water-treatment facility, flood protection, and a sewer system for downstream communities.)

    Removing the dams should take 3 years. A draft plan calls for draining the lake and blasting the Elwha Dam apart. The taller Glines Canyon Dam will be cut into 22-ton blocks and trucked away. Once the river runs free, it will wash away an estimated 40% of the 14 million cubic meters of sediment trapped behind the dams—far more than has ever been released from a dam before. “This would be an extreme case, but we don't anticipate any problems” for wildlife, says project manager and fisheries biologist Brian Winter of Olympic National Park. (Sediment likely won't be an issue at Hetch Hetchy; only a few centimeters are thought to have accumulated behind O'Shaughnessy, because the granite watershed erodes slowly.)

    Scientists would like to study the effects of sediment release on the Elwha, but there are no funds for research in the restoration budget. “We're trying to document the baseline conditions,” says Jerry Freilich, research coordinator for Olympic National Park. Local universities have received a $1 million National Science Foundation grant to coordinate research efforts, but obtaining overall funding has been tough, Freilich says.

    The sediment that remains in the valley will appear like natural river terraces, Winter says. Some 227 hectares of forest will be restored by planting native seeds and trees of various ages; the idea is to quickly create a diverse ecosystem in the hope of keeping invasive species from gaining a foothold.

    Scientists say the salmon stand a good chance of recovery. Once the dams are removed, they will face few threats because most of the watershed is protected within Olympic National Park.


    Unraveling Pain's DNA

    1. Jennifer Couzin

    The genetics of pain, long overlooked, is now getting attention—but identifying the genes at work isn't an easy task

    Neuroscientist Marshall Devor used to judge the aftermath of amputations much like everyone else. Some who have lost an arm or leg perceive a searing pain in the limb that's no longer there, whereas others are untroubled. The going theory was that this so-called phantom pain is psychological: “Some people can accept the loss of the limb, and some can't and spend their lives mourning,” says Devor, who works at The Hebrew University in Jerusalem, Israel.

    Then, about 2 decades ago, Devor's perspective shifted. He found that the offspring of rats who reacted strongly to a nerve injury in their leg, scratching and nibbling at their toes as if they were in pain, responded to weak stimuli with distress, unlike those born to rats less troubled by the same nerve injury. That research, published in 1990, was among the first to suggest that pain sensitivity has a genetic component.

    Pinpointing the genes that predispose to pain, particularly chronic forms caused by nerve injuries, could help guide development of new pain treatments and even prevention. Such clues are desperately needed. Roughly 50 million adults in the United States suffer from persistent pain; it accounts for more than 20% of doctor's visits and 10% of health care dollars. “The solutions offered to patients are not satisfactory, and those that are cost dearly in terms of side effects,” says Ze'ev Seltzer, a pain researcher at the University of Toronto in Canada.

    But perhaps more than other complex diseases spurred by a mix of problem genes and environmental insults, the pain field has faced an uphill battle in finding relevant genes. The role of a gene identified several years ago as an important key to pain sensitivity is now being questioned, for example. “Even 5 years ago, people really doubted that pain was genetic at all,” says Luda Diatchenko, a geneticist at the University of North Carolina, Chapel Hill (UNC-CH), who is exploring the roles of genes in facial pain.

    Still, a shortlist of so-called pain genes is emerging, and with a report in Nature Medicine this week, scientists tentatively added another. That gene, GCH1, is the first to be linked to neuropathic pain, a common, difficult-to-treat chronic condition caused by nerve damage that affects more than 2 million people in the United States.

    A genetic thicket Without an objective means of measuring pain, and with chronic pain patients exhibiting enormous variability in symptoms, designing human studies that produce lasting results has been challenging. And with hundreds of genes apparently influenced by pain in animal research, knowing which ones to pursue, and how influential they really are, is daunting, say researchers.

    At risk.

    Knowing who's most susceptible to pain could help surgeons take extra precautions when operating near major nerves.


    To find GCH1, a team led by pain researcher Clifford Woolf at Massachusetts General Hospital in Boston started with what Woolf calls “a fishing expedition.” They began by damaging nerves in rats and assessing how gene expression changed with the injury. The number of genes in nerve cells whose activity shifted was overwhelming—about 1500 in all. To Whom It May Concern: pinpoint those that affected pain sensitivity rather than ones simply reacting to an insult, the researchers looked for altered expression that persisted for 6 weeks following nerve injury. That shrank the number of genes about 10-fold, to roughly 150. That was “still too many to deal with one at a time,” says Woolf, so the team examined whether any of those genes were known to work together in a common pathway. That highlighted a trio of genes.

    Then Woolf's group turned to Mitchell Max of the National Institute of Dental and Craniofacial Research (NIDCR) in Bethesda, Maryland, who has studied pain genetics in people, including a cohort of 147 people who were followed for 2 years after back surgery to relieve leg pain from a herniated disc. The researchers asked the volunteers to rate their pain every 3 months and also examined their DNA to see whether variations in any of the three genes correlated with the pain ratings. Two showed no effect.

    But a version of GCH1 identified by a combination of 15 single-nucleotide polymorphisms (SNPs) was associated with less neuropathic leg pain in the first 2 years after surgery. People with two copies of that gene variant rated their pain as 0.06 on average, whereas those with no copies rated their pain 0.8 (Those with one copy rated their pain 0.44). GCH1 controls production of a chemical called BH4, and Woolf's team found that administering it to rodents made sensory neurons more excitable.

    It's not clear yet whether the GCH1 connection will hold up in larger cohorts and those encompassing different types of pain. Still, the genes that have pain researchers most intrigued are those, like GCH1, that appear to influence the excitability of neurons. Although some studies, such as the one on facial pain in which Diatchenko is participating, focus on common chronic pain syndromes, other researchers are hoping that inherited pain disorders may be easier to dissect genetically and shed light on pain in general. At the Society for Neuroscience meeting in Atlanta, Georgia, last week, Stephen Waxman, a neurologist at Yale University, detailed the genetic mutations his group has found in a rare familial neuropathic pain syndrome called erythromelalgia. The people affected experience excruciating pain in their hands and feet when exposed to slight warmth, and abnormal vasculature turns their limbs bright red.

    The mutations alter the gene for a sodium channel, a type of molecular gate that controls neural signaling. When this sodium channel has one of the mutations seen in erythromelalgia, it causes sensory neurons to fire with little provocation. “They scream when they should be whispering,” says Waxman. And whereas sodium-channel mutations have not been linked to more prevalent kinds of chronic pain, Waxman's group and some British scientists have found that the channel appears to play a role in inflammatory pain in animals. “We're beginning to ask the question, ‘Are there polymorphisms [in this gene] … that don't cause disease but are associated with high or low thresholds of pain?’” says Waxman.

    Increasingly, scientists believe that a person's pain thresholds reflect their risk of developing chronic pain. After all, only 5% to 15% of people wounded in car accidents or by gunshots, or suffering from shingles, will develop chronic neuropathic pain—perhaps because they possess a combination of genetic mutations that increases their sensitivity to pain.

    The face of pain As the GCH1 story shows, finding gene variants behind pain is a complex task. The tool typically employed to tease out the genetic component of other complex diseases—twin studies—is nearly impossible to use in chronic pain because few twins will suffer the same environmental insult that leads to pain. “Chronic pain is probably the classic example of gene-environment interaction,” says Jeffrey Mogil, a neurogeneticist at McGill Universi ty in Montreal, Canada.

    Another challenge in pain genetics is knowing whom to study. For example, in 2003, researchers led by Jon-Kar Zubieta of the University of Michigan, Ann Arbor, and David Goldman of the National Institute on Alcohol Abuse and Alcoholism in Bethesda, Maryland, reported in Science that among people, a variation in a gene for an enzyme called COMT (catechol-O-methyltransferase) modulated the μ-opioid system (21 February 2003, p. 1240). That system naturally helps the body control pain. The find initially electrified the research community, because it suggested that the gene influences a person's pain sensitivity.

    Tracking pain genes.

    Nearly 1200 genes show expression changes (above) after a rat endures nerve damage. Scientists homed in on one of those genes and found that its protein product boosts calcium (colored dots) in neurons, making them more excitable.


    But efforts to confirm a broad role for the gene in pain have faltered. One possible explanation, says Woolf, is that various research teams have focused on different “phenotypes”: individuals with different types of pain. A study led by Raymond Dionne of NIDCR reported this summer that the gene for COMT played little role in pain sensitivity following wisdom tooth surgery. The original Science study, on the other hand, exposed 29 healthy volunteers to painful injections in jaw muscles. That sample size is small, note researchers, and it's still not clear how much overlap exists between genes that govern experimental pain and those guiding chronic pain sensitivity or susceptibility.

    Most pain researchers, however, still believe that COMT has a role to play. Last year, Diatchenko and her colleagues found that different combinations of four SNPs in COMT affected the risk of developing a form of musculoskeletal facial pain known as temporomandibular joint disorder. Those with one particular combination of SNPs were less than half as likely to suffer from the disease and were much more resistant to pain. “The [COMT] story is probably a lot more complicated than we thought,” says Mogil.

    Indeed, Mogil has found in mice that the genes governing hypersensitivity to touch are generally not the same as those influencing hypersensitivity to cold, or to heat. “Our animal studies show very clearly that all these symptoms dissociate from each other,” he says, suggesting that in different pain phenotypes, the genetic combinations at work vary.

    In humans, however, various types of pain are often lumped together, and it's virtually impossible to distinguish between the physical pain cause by overly excited sensory neurons and the patient's emotional response to pain. Both, says Diatchenko, feed into an individual's perception of his or her pain.

    Diatchenko hopes that the facial pain study she's involved in, which is led by her colleague William Maixner of UNC-CH, may provide a framework for teasing apart genetic and environmental drivers of chronic pain. The study, which garnered $19 million from the National Institutes of Health—a remarkable figure, given that only 1% of the agency's $28 billion budget goes to pain research—will follow 3200 healthy individuals and 200 who have facial pain. Roughly 5% to 15% of the healthy group is expected to spontaneously develop facial pain as well. The researchers will hunt for both environmental factors and genetic candidates that appear to increase an individual's susceptibility to such facial pain and other pain conditions.

    “The main question is, ‘Can we predict the people who are predisposed to chronic pain conditions?’” both facial pain and beyond, says Diatchenko. Such a skill could allow physicians to take extra care in potentially dicey scenarios—such as offering additional protection to nerves at risk during surgery. Given the complexity and the halting pace of pain genetics research so far, that would be a giant step forward.


    Failure Is Not an Option for These Minority Students

    1. Yudhijit Bhattacharjee

    Southern University physicist Diola Bagayoko uses tough love to expand and diversify the pool of scientific talent


    Sharon Daniels was a physics major at Southern University (SUBR) in her hometown of Baton Rouge, Louisiana, when she got married, had a baby, and dropped out of college. When the marriage went sour, she took a job in Houston, Texas. But 2 years later she was back in Baton Rouge, where she learned that her former professor, Diola Bagayoko, wanted to see her.

    When Daniels showed up at his office, Bagayoko gave her a scolding. “If you're thinking you'll take care of your kid right now and finish your degree later, you are putting yourself in quicksand,” Bagayoko told her. He asked Daniels to think about her high school friends, few of whom were doing well. Then he turned on the charm. “You have the talent and the intellect needed to do this,” he said. Her 3.0-plus grade point average made her a good candidate for financial aid, he added, and her coursework was recent enough that it would still count toward her degree.

    The sales pitch worked, and in 1992 Daniels graduated and began a career as a software programmer and technical writer. For 2 decades, Bagayoko has helped African-American students like Daniels earn science and engineering degrees from SUBR, a historically black institution where a significant percentage of students are the first in their family to attend college. And he continues to mentor them through graduate programs around the country and into scientific careers. His efforts have earned him two presidential mentoring awards and persuaded his university, a predominantly undergraduate institution, to make mentoring a factor in its tenure and promotion process.

    Bagayoko, who grew up in Mali and came to the United States for graduate school, has done much of this work through the Timbuktu Academy, a program he started in 1990 with funding from the National Science Foundation (NSF) and the Defense Department's Office of Naval Research. Named after the West African university that stood on the banks of the Niger River from the 12th to the 16th centuries, the academy conducts intensive summer camps for middle and high school students to prepare them for science and engineering majors in college. It also shepherds a handful of students through undergraduate science and engineering programs at SUBR by providing them with academic advice, extra tutoring, and a solid research experience outside the classroom. Although the program is open to any student, nearly all of the applicants are from racial and ethnic groups traditionally underrepresented in science, and the majority are African-American.

    Law of success.

    Diola Bagayoko says that learning lessons to mastery is a foolproof road to success for students.


    Bagayoko, 57, is proud of his record. Of the 600 high school students who have attended the academy's summer programs, 80% have gone on to major in STEM (science, technology, engineering, and mathematics) disciplines at colleges around the country. Of the 150 students who have earned their bachelor's degree from SUBR with support from the academy, more than 60% have pursued advanced degrees in scientific disciplines.

    Although comparisons are difficult because of the paucity of good longitudinal data, the program is one of the most effective pipelines for channeling African Americans into science and engineering careers, says Anthony Junior, manager of the Department of Navy's Historically Black Colleges and Universities program, which has funded the academy at $600,000 a year since 1993. Bagayoko's own department has reaped the rewards: On a campus that loses half of its freshman class, 90% of firstyear students who choose to major in physics—nearly all of them academy scholars—earn a degree in 4 years.

    Since 1995, Bagayoko has replicated the academy's mentoring model across 10 other Louisiana institutions with a grant from NSF's Louis Stokes Alliance for Minority Participation (LSAMP) program. Funding officials and colleagues familiar with Bagayoko's work say he succeeds by using time-tested ingredients for good mentoring—building students' self-confidence, involving them in research, and monitoring them closely—and adding in his unique blend of kindness and charisma. “Most of these practices are laid out in the literature,” says A. James Hicks, NSF's program director for LSAMP. “But it takes special individuals like Diola Bagayoko to implement them.”

    Paying forward Bagayoko's ever-present suit and tie belie his youthful exuberance. He uses an expressive face and a deep, distinctive voice to great effect in the classroom. There's a strong hint of French colonial Africa in his speech, which he salts with vigorous gestures. Peering over his glasses to gauge his listener's reaction, he laughs loudly and slaps his knee after making a point. Students stream in and out of his office for help with assignments, which he crams into a punishing schedule that stretches into the evening and includes weekends.

    Bagayoko traces the origins of his passion to help the underserved to his teachers in Bamako, Mali's capital. One helped him skirt an age limit for entering secondary school, and another expanded his horizons with a collection of books by Victor Hugo. “The only way I could thank him was by reading them backward and forward. My capacity in French ballooned as a result,” he says.

    After getting a bachelor's degree in physics and chemistry in Mali, Bagayoko came to the United States to study solid state physics at Lehigh University in Bethlehem, Pennsylvania. Moving to Louisiana State University in Baton Rouge for his Ph.D., Bagayoko recalls how his dissertation adviser arranged with the school chancellor to keep the university's computing center open during holidays so that Bagayoko could have uninterrupted access to the facility. In his first year, the adviser paid for him to attend an American Physical Society conference in Chicago, Illinois, even though he didn't have anything to present. “I vowed that I'd be back at next year's conference with a presentation of my own,” he says. He kept the promise.

    Bagayoko didn't forget those experiences when he joined the SUBR faculty in 1984. “I realized that I was the product of the good work of many people,” he says. “I wanted to say thanks.” At the urging of his chemist wife and fellow SUBR professor, Ella Kelley, he created a structured mentoring program based on the simple idea that an individual becomes more proficient at a task with practice.

    The concept is embodied in a 1920s theory called the power law of human performance. Bagayoko uses it as a motivational tool in combination with the idea that most knowledge—particularly scientific knowledge—is acquired cumulatively. “The typical African-American student enters college with elements in his background that are unfavorable to learning—bad grammar, poor vocabulary, a poor grounding in basic math—none of which is his fault,” he says. But if a professor is willing to fill those holes, “success is guaranteed.”

    Over the years, Bagayoko has wielded the power law like a machete to eradicate the selfdoubt among many African-American students toward science. “I tell them that irrespective of what they may have heard before, there's a law out there that not only says they can do well in science but also describes how.” The program also helps high school students improve their grammar and vocabulary skills, increasing their chances of attending a good college.

    In mentoring undergraduates supported by the academy, Bagayoko puts great emphasis on research, both with professors on campus during the school year and in labs around the country during the summer. Students who have worked with him say he monitors their progress closely, using carrots such as a chance for extra coaching and sticks such as the threat of pulling their financial aid.

    “He asks questions like: Why are you spending so much time with your sorority?” says Zelda Gills, one of his earlier students who is now a scientist at the U.S. Nuclear Regulatory Commission. “When he wants you to do something, he never says: ‘Could you do this?’ It's always: ‘You will do this.'He can be very stern, but you know that it's for your own good.”

    Better things to do The 34-year-old building where SUBR's physics department is located bears a tired look. Several lights in the hallways and bathrooms are burnt out, and some of the water fountains don't work. But neither the threadbare conditions nor the oppressive August heat stop Bagayoko from delivering his message to the incoming class of academy and LSAMP scholars.

    His assistant distributes a handout describing the power law, his gospel. “One thing it tells you is that if you are studying a lesson and cannot understand it, it probably means there is some critical background material that you may not have,” he booms. “Go see a faculty member to find out what it is.”

    The 1-hour lecture includes suggestions on how to behave outside the classroom, including avoiding fights. “I won't fight, not because I can't, but because I have sound judgment,” he counsels them. “When I get into a situation like that, I say to myself, ‘This person probably doesn't manipulate Maxwell's equations as well as I do. I have better things to do, like developing new theories or building new devices.'”

    Bagayoko then rattles off the names of former academy members who, presumably, took his advice to heart. He mentions Anthony Pullen, an SUBR graduate now studying theoretical astrophysics at the California Institute of Technology in Pasadena. “A few years ago, these people were sitting in this auditorium, just like you,” he says. “They delivered for themselves and their families. You can, too.”

    The students say they welcome the guidance. “Some of us here need to be told and retold that academic achievement is valuable,” says Jonathan Dooley, a freshman who grew up in an impoverished Los Angeles, California, neighborhood. Dooley's African-American father left when he was very young, and his Hispanic mother told him in kindergarten that he would end up homeless if he didn't go to college. “Knowing that there are blacks and Hispanics out there with Ph.D.s in science means a lot to me,” says Dooley.

    Bagayoko's impact can extend far beyond a student's professional training. Two years ago Daniels, who has stayed in touch with Bagayoko, asked him to consider her daughter, Zephra Bell, whom she had home-schooled, for admission into the academy. He did, and Zephra made the cut: She is now 2 years away from earning a bachelor's degree in physics at SUBR. “I had no ideas about her going anywhere else,” Daniels says. “She's in good hands.”

    Generation 2.0.

    Zephra Bell and her mother are both graduates of Bagayoko's Timbuktu Academy.


    An Even Drier-Looking Moon

    1. Richard A. Kerr

    NASA would like nothing better than to find water on the moon. Astronauts could drink it as well as convert it to rocket fuel for their leap on to Mars. The agency's immediate plans for lunar exploration are largely geared to the search for lunar water ice, but two new studies have failed to find any sign of it, despite previous reports of ice deposits cached in the deep chill of permanent shadows. It appears that nothing short of a dedicated rover mission could settle the question.

    At the meeting, a new analysis raised questions about signs of water returned by an orbiting spacecraft. Planetary scientist David Paige of the University of California, Los Angeles, and colleagues looked for places on the moon where the sun never shines—in the shadows of crater walls near the poles. Presumably, water delivered by impacting comets over the eons could have made its way to these cold traps and been preserved as ice just beneath the surface of the loose soil. Paige and his team calculated lunar temperatures across the surface and the subsurface, starting with the chilling effect of shadows and including heating by reflected sunlight and by adjacent sun-warmed rock.

    There are indeed crater-hosted cold traps near the poles as cold as 50 kelvin, the group found. But earlier reported signs of ice do not necessarily coincide with the cold traps. Eight years ago, the orbiting Lunar Prospector measured neutron emissions from the moon induced by cosmic rays. It found what looked like deposits of hydrogen—presumably in the form of water ice—in the right general areas (Science, 13 March 1998, p. 1628), the polar regions, but mostly not where the calculated cold spots are. “We can probably say with some confidence that not all cold traps are filled with ice,” Paige says.

    Another new study questions the other sort of evidence for lunar ice. In the 19 October issue of Nature, planetary scientist Donald Campbell of Cornell University and colleagues report that the highest-resolution radar study yet of the moon's south polar region appears to rule out rich ice deposits there. Radar signals bounced off the moon in 1996 by the orbiting Clementine spacecraft and received on Earth had hinted at massive ice deposits in craters near the moon's south pole.

    Not ice.

    A radar signal associated with ice (yellow-green, right) appears not only in shadowed Shackleton crater (bottom) but also in sunlit areas.


    When Campbell and his colleagues used two giant Earth-based radio dishes to bounce radar signals off the moon, they did find Clementine's telltale signal—an unusual effect on the reflected signal's polarization previously associated with ice. But, thanks to the 20-meter resolution, they could see that the polarization effect was usually in the wrong places. Although it appeared in the permanently shaded wall of Shackleton crater, for example, it also showed up in well-lit Schomberger crater and around many smaller young craters, all areas roughened by crater ejecta and slumping rock. “Right now, the explanation for the lunar [polarization effect] has something to do with reflection between rocks and boulders rather than ice at the poles,” says planetary scientist Bruce Hapke of the University of Pittsburgh in Pennsylvania.

    The new studies cast a shadow on NASA's next lunar mission: an ice-oriented scientific exploration of the moon meant to pave the way for humans' return. Most of the instruments on the Lunar Reconnaissance Orbiter (LRO), to be launched in October 2008, can measure properties relevant to lunar ice. And the piggyback experiment to LRO—a crash landing into a shadowed crater, intended to kick any ice there into view—is all about water. Not everyone is optimistic. “I don't think you can [prove the existence of ice] remotely,” says planetary scientist William Feldman of the Planetary Science Institute in Tucson, Arizona; he headed the Lunar Prospector neutron investigation. “You have to go there in a rover. That's hard, especially if it's 80 K.”


    Titan Lives--Geologically, at Least

    1. Richard A. Kerr

    Saturn's largest moon, Titan, suffers under its heavy atmosphere, as the Cassini spacecraft and its Huygens lander quickly revealed after they arrived. Brooding clouds, icy terrains gouged by river-cut channels, lake-dotted high latitudes, and great dune fields attested to geologic activity imposed from above. And Titan had also driven surface changes from within itself, at least in the geologic past. Flows of icy “lava,” which had obviously erupted from inside Titan, lace the landscape.

    Now Cassini team members report the first detection of a change on the surface of Titan since Cassini's arrival, and it appears to be powered from within. “Once thought of as frozen in time, Titan should be added to the bodies with active volcanism,” said Cassini team member Robert Nelson of the Jet Propulsion Laboratory in Pasadena, California.

    Cassini's view of Titan's ongoing geologic activity remains fuzzy. On its first pass by the moon, in July 2004, members of the Visual and Infrared Mapping Spectrometer (VIMS) team noticed a bright spot in Titan's southern mid-latitudes. At 70,000 square kilometers, it was the brightest part of the moon. Then it got brighter. It doubled in brightness and in size by March of 2005 and then dimmed and shrank back to its original appearance by November of the same year, Nelson reported at the meeting. Then it went through the same cycle again by March of this year. “This is a major event,” said Nelson. After comparing the spot with adjacent areas, he and VIMS team colleagues conclude it isn't a cloud or a fog bank. “We're fairly comfortable with the idea that change is happening” on the surface, he says.


    Between Cassini visits, something came out of Titan to intensify its bright spot.

    CREDIT: J. W. BARNES ET AL., SCIENCE 310, 5745 (2005)

    “The observations are spectacular,” says planetary physicist David Stevenson of the California Institute of Technology in Pasadena. The changes are generated from within, he agrees. “The question is, what is the actual process?” He feels “volcano” is too strong a word to use at this point, evoking as it does great gushings of magma. In the case of frigid, icy Titan, any gushings would likely be of a slushy water-ammonia mix. Stevenson, who did the early work on such chilly eruptions, leans toward some lower-energy process: something unlike anything on Earth, which could still alter an area the size of Ireland in a month or two. Suggestions are welcome.


    The Kuiper Belt Loses Some of Its Mystery

    1. Richard A. Kerr

    For 200 years, scientists have believed that the solar system emerged from a swirling disk of gas and dust. But that doesn't begin to explain the myriad peculiarities of the solar system, so planetary dynamicists are striving for a “theory of everything”: one all-encompassing scenario that will put each planet, asteroid, and icy leftover of solar system formation in its proper place. A recent contender—one in which the early solar system “goes crazy for a while”—got another test at the meeting.

    About the most peculiar part of the solar system is the Kuiper belt, the disk of icy remnants beyond (and including) Pluto. Kuiper belt objects (KBOs) just haven't behaved the way leftovers from a simple disk should. For example, the outer edge of their disk ends abruptly at 50 times the Earth-sun distance, for no obvious reason. Some KBOs lead well-ordered lives in nearly circular orbits in the same plane as the planets, whereas others fly around in inclined, elongated orbits. The list goes on.

    With so many quirks, the Kuiper belt seemed like a good test for a model of solar system evolution developed by dynamicist Alessandro Morbidelli of the Observatory of the Cîte d'Azur in Nice, France, and three international colleagues. Their “Nice model” had already done a credible job of getting the four outer planets into slightly elongated and tilted orbits and raining debris into the inner solar system in the so-called late heavy bombardment (Science, 3 December 2004, p. 1676). The trick was to start the Nice model with the newborn outer planets closer in and more tightly bunched than they are at present. Then Saturn would drift outward until falling into a gravitational link with massive Jupiter. Jupiter could then pump orbital energy into Saturn, which in turn would stir the outermost solar system into a chaotic frenzy.

    In their new modeling, Morbidelli and his colleagues followed the fate of lingering planetesimals flung outward by orbitally crazed Uranus and Neptune. In the end, “we succeed pretty well,” says Morbidelli. The model's planetesimals end up more or less where the KBOs are today and usually in about the right amounts. They do that by filling the space made chaotic by the Jupiter-Saturn link and getting stranded there when Saturn breaks out of its jovian gravitational interaction. The outer edge of the disk is where the continuous orbital chaos ends, for example.

    “They're putting together a nice story,” says dynamicist Jack J. Lissauer of NASA's Ames Research Center in Mountain View, California. Nice but not perfect, he adds. For example, the Nice model—like all others—fails to produce enough KBOs in particularly elongated and inclined orbits. Dynamicist Renu Malhotra of the University of Arizona, Tucson, has a more fundamental reservation. “I'm not convinced their model's initial conditions are quite plausible,” she says. She doesn't see how that many planetesimals could linger 700 million years until the late heavy bombardment. So she would like to see yet more KBO peculiarities tested.


    Snapshots From the Meeting

    1. Richard A. Kerr

    Breakups. Planetary bodies tend to run into each other in our crowded solar system. But three unrelated reports at the meeting brought home just how frequent—and recent—catastrophic collisions have been. Planetary astronomer Kristina Barkume and her colleagues at the California Institute of Technology in Pasadena reported the first discovery of a “family” of Kuiper belt objects beyond Pluto. The newly recognized family includes the 2000-kilometerlong “parent” 2003 EL61 and three 100-kilometer fragments, all following nearly identical orbits since EL61 suffered a catastrophic collision.

    Closer to home, planetary scientist David Vokrouhlický and colleagues at the Southwest Research Institute in Boulder, Colorado, identified four new families in the asteroid belt that could be traced to collisions in the past 600,000 years, the most recent just 70,000 years ago. That raises the possibility that asteroidal dust from collisions might be preserved in Antarctic ice cores.

    And planetary ring specialist Matthew Hedman of Cornell University and colleagues reported that a spiral ring of Saturn imaged in 1995 by the Hubble Space Telescope had tightened up by 2006 when the Cassini spacecraft imaged it. The spiral ring, they conclude, must actually be shadow-casting corrugations in the broader D ring, the corrugations having been formed by a recent impact. Quite recent, in fact: 1984.


    Something hit Saturn's innermost ring in 1984 to create corrugations.


    Cataclysm confirmed. The humongous impact craters that create the “man in the moon” seem to have formed in one horrendous storm of giant impactors 700 million years after the solar system's formation. But that could be deceptive, some planetary scientists have argued. Those impacts may have been just the tail end of a dwindling rain of bodies left over from the rather messy birth of the solar system. Dynamicist William Bottke and colleagues at the Southwest Research Institute in Boulder, Colorado, decided to test the declining-bombardment scenario by simulating the fate of lingering planetesimals in a computer model. When they put in enough massive bodies to pummel the moon long after its formation, the bodies collided with one another and ground themselves down until they were too small to do the job. Whatever battered the moon, they conclude, it wasn't the tail end of solar system formation.