News this Week

Science  22 Sep 2006:
Vol. 313, Issue 5794, pp. 1712
  1. GENDER ISSUES

    Universities Urged to Improve Hiring and Advancement of Women

    1. Andrew Lawler

    U.S. universities foster “a culture that fundamentally discriminates against women,” says a new report by the National Academies on the status of women in academic science and engineering. Their underrepresentation is “deeply troubling and embarrassing,” according to the report, which suggests that institutions create a body to collect data, set standards, and ultimately monitor compliance to increase the number of women in technical fields.

    Draining the pool.

    Women scientists are underrepresented at the entry level within certain disciplines in academia.

    SOURCE: NATIONAL SCIENCE FOUNDATION (2006) SURVEY OF DOCTORAL RECIPIENTS (2003)

    Beyond Bias and Barriers: Fulfilling the Potential of Women in Academic Science and Engineering cites research demonstrating that women are paid less, promoted more slowly, bypassed for honors, and subjected to implicit gender bias from both their male and female colleagues. The 18-member panel—chaired by Donna Shalala, president of the University of Miami in Coral Gables, Florida, and made up primarily of female university presidents, provosts, and senior professors—also finds no scientific basis to the argument that inherent differences between the genders are at the root of the problem. “This report confronts the myths; it is a data and information-driven study,” says Donna Dean, a biochemist and former National Institutes of Health official who is senior science adviser with the Washington lobbying firm Lewis-Burke Associates. But others, such as chemist and activist Debra Rolison of the Naval Research Laboratory in Washington, D.C., expressed disappointment that the panel didn't come out more strongly for aggressive use of existing federal laws.

    The 18 September report is the latest in a series of private and government studies examining the status of women in senior science and engineering positions across the country. One of its few concrete proposals is an “interinstitution monitoring organization” to set norms for expanding the role of women in the sciences and engineering. The organization, the panel suggests, would be similar to the National Collegiate Athletic Association, which serves as an intermediary between universities and federal agencies. The American Council on Education has agreed to convene several national education organizations to “define the scope and structure of data collection,” says ACE Vice President Claire Van Ummersen. “This would be a way for the profession to police itself,” says Nancy Hopkins, a biologist at the Massachusetts Institute of Technology (MIT) in Cambridge, who chaired a study in 1999 focusing on the problem at her university.

    But Rolison criticized the panel for not demanding greater accountability. That includes strict enforcement of a 1972 law, popularly known as Title IX, that prohibits any education program or activity receiving federal funding from denying equal benefits to women. “That's the missing piece,” she says. Shalala acknowledged at a press conference that the federal government has spent more time and energy ensuring equity on collegiate playing fields than in the laboratory. “There are laws on the books which are not being enforced,” she added. Shalala later told Science that the report's focus is “not any individual law, but all enforcement. … Institutional leaders and professional societies have to make systemic changes to provide opportunities.”

    The fundamental problem, the panel notes, is not attracting women into science but retaining them once they are trained. “The pipeline is in better shape than I thought,” says Ana Mari Cauci, a panel member and a psychologist at the University of Washington, Seattle. At MIT, for example, more than half of science undergraduates are female, and more than one-third of engineering students are women. “It is not lack of talent but unintentional biases and our outmoded institutional structures that are hindering the access and advancement of women,” the report states. For example, the report says the culture still favors academics with a stay-at-home spouse—typically a wife. Fewer than half the spouses of male faculty members in the sciences are employed full-time, whereas 90% of the husbands of women faculty members work outside the home.

    The gap widens with seniority, the report notes. At leading research universities, fewer than 15% of full professors in the life sciences are women, and in the physical sciences, that figure remains in the single digits. “Women from minority racial and ethnic backgrounds are virtually absent from the nation's leading science and engineering departments,” the study adds.

    The panel dedicated the report to Denice Denton, a panel member and chancellor of the University of California, Santa Cruz, who committed suicide in June (Science, 30 June, p. 1857).

  2. GEOLOGY

    Katrina Study Stirs Debate on Coastal Restoration

    1. Erik Stokstad

    A maverick ecologist is suggesting that some of the massive and costly engineering fixes being used to restore coastal wetlands in Louisiana will barely make a dent in the problem.

    In a paper published online by Science this week (www.sciencemag.org/cgi/content/abstract/1129116), Eugene Turner of Louisiana State University in Baton Rouge and three LSU colleagues report the first coastwide study of sedimentation from hurricanes Katrina and Rita. They conclude that hurricanes are by far the most important source of inorganic sediments in the wetlands, dumping so much that, in comparison, costly schemes to channel sediment-bearing Mississippi River water back to the wetlands will have a “trivial” effect. Instead, they argue, restoration efforts should focus on restoring the buildup of organic material.

    Muck galore.

    Hurricane Katrina covered coastal wetlands with an abundance of silt. Based on new measurements, some researchers argue that hurricanes provide almost all the inorganic sediment the ecosystem needs.

    CREDIT: R. E. TURNER

    Many of Turner's counterparts in the ecological community disagree, however, saying that although the researchers have marshaled useful new data, the measurements don't justify their conclusions. “It would be very unwise to use this study to overthrow the thinking about coastal restoration,” says physical geographer Torbjörn Törnqvist of Tulane University in New Orleans, Louisiana. “We need to be extremely careful” about interpreting the new results.

    Most experts trace Louisiana's coastal degradation in large part back to the levees that were built in the 20th century to control the Mississippi River (Science, 25 November 2005, p. 1264). They contend that the levees prevented floods from delivering the necessary silt to delta wetlands. As a remedy, the state of Louisiana and the federal government spent $145 million to construct a pair of prototype structures in 1991 and 2002 to divert river water into wetlands. Several more structures are proposed in a bill before Congress.

    But hurricanes also dump mud and debris onto wetlands, and Turner had long suspected that hurricanes might be an even bigger source of sediment than the mighty Mississippi. Katrina and Rita gave him a chance to find out.

    Using a rapidly awarded grant from the National Science Foundation, Turner and his colleagues chartered a helicopter in early November 2005 and took samples of storm-surge deposits from 186 sites across 38,588 square kilometers of coastal wetlands. They found plenty of muck. On average, the muddy sediment was 5 centimeters thick; that means Katrina and Rita left a combined 130 million metric tons of sediment on the wetlands, Turner and his colleagues calculate.

    Other ecologists welcome these new measurements, but they take exception to Turner's next, critical, assumptions. Based on a scanty historical record, Turner and his colleagues estimate that storms with a surge as big as Katrina's hit the Louisiana coast on average every 7.9 years. At that frequency, hurricanes deposit about 26 million metric tons of sediment a year on wetlands and associated open water—more than five times the amount contributed by the Mississippi River floods before the levees were constructed, Turner and his colleagues calculate.

    Turner says his analysis bolsters his contention that Louisiana's wetlands don't face a shortage of inorganic sediment. The major cause of wetland loss, Turner has long argued, is canals dug for oil and gas drilling that changed the hydrodynamics of the region. This, in turn, he believes, stunted and killed plants and retarded the buildup of organic materials. He favors filling these canals and restoring adjacent marshes.

    Many other experts, however, suspect that Turner has overestimated the sedimentation rate of hurricanes. First, they say, surges probably eroded shallow bays and then dumped the silt on the marsh. “It's robbing Peter to pay Paul,” says Joseph Kelley of the University of Maine, Orono. In addition, they believe that major storms such as Katrina strike much less often than Turner and his colleagues estimate.

    They also point out that diversion projects not only supply sediment but also help reduce salinity and provide nutrients. In fact, Denise Reed of the University of New Orleans and others advocate constructing an even larger diversion of the Mississippi River, to build substantial new land south of New Orleans. “If you don't have diversions as a major part of your restoration efforts, you can't save the coast,” says John Day of LSU, who has studied one of the diversions for a decade.

  3. GENETICALLY MODIFIED CROPS

    Tracing the Transatlantic Spread of GM Rice

    1. Gretchen Vogel

    Amid product recalls and plummeting prices, scientists are trying to figure out exactly how traces of an experimental variety of genetically modified (GM) rice ended up in commercially available supplies in the United States and Europe. Although the herbicide-resistant strain was never approved or marketed, traces of it have appeared in samples collected on both continents. Agriculture officials stress that the rice poses no health threat, but its spread is a cautionary tale that introduced genes may be harder to contain than some scientists and industry leaders had hoped. The finds “set a really bad example for genes that we do want to keep contained,” says plant geneticist Norman Ellstrand of the University of California, Riverside.

    Fertile questions.

    Scientists are trying to trace how an experimental strain of genetically modified rice spread to rice sold in the U.S. and Europe.

    CREDIT: KAREN TAM/WINSTON-SALEM JOURNAL/AP PHOTO

    The variety, called Liberty Link 601 (LL601), was grown in test plots in several states between 1998 and 2001. Designed to be resistant to the broad-spectrum Liberty herbicide sold by Aventis CropScience (later bought by the German company Bayer), it was not as successful as hoped, and Aventis discontinued research on the strain in 2001. In late July, Bayer notified the U.S. Department of Agriculture (USDA) that it had found traces of LL601 in commercial samples of long-grain rice stored in Arkansas and Missouri. When USDA announced the find two and a half weeks later, U.S. rice prices fell by nearly 10% in 2 days.

    On 11 September, European Union officials confirmed that 33 of 162 samples tested by rice millers across Europe, a major importer of U.S.-grown rice, had shown traces of LL601. Officials in Sweden and France also said they found traces of the gene in commercially available rice. And Greenpeace said it had found traces of LL601 in rice for sale at Aldi supermarkets in Germany, prompting a nationwide recall.

    How the gene spread so far is still a mystery. Rice is thought to pose a relatively low risk of cross-contamination because it self-pollinates, often before the flower even opens, lowering the likelihood that wind or insects could spread GM pollen. Steve Linscombe, a rice breeder at Louisiana State University (LSU) in Baton Rouge, where some of the test plots were grown, says they strictly followed USDA standards, exceeding the minimum requirements for buffer zones between the test plots and conventional rice. However, the university did say it found “traces of genetic material” from LL601 in samples of foundation seed rice grown at LSU in 2003 for the widely grown Cheniere variety. Foundation seed is the original stock of a commercially available variety. It is distributed to seed-producing farmers, who then plant it to grow seed rice that is sold nationwide. Linscombe says the university is working with USDA to determine how the LL601 gene could have entered the Cheniere seed stocks.

    Doug Gurian-Sherman of the Center for Food Safety in Washington, D.C., says regulations designed to limit the spread of introduced genes should require more extensive testing of such seed stocks. The possibility of contamination “needs to be taken seriously,” he says. Ellstrand says that a careful investigation of what led to the spread will be crucial for scientists planning field trials of GM plants that contain more sensitive genes, such as those for pharmaceuticals or industrial products.

  4. BIOETHICS

    Researchers Attack Newspaper Probe of Trials

    1. Jocelyn Kaiser

    More than 100 clinical researchers have published a scathing critique of a lengthy newspaper article, which had suggested that a National Institutes of Health (NIH) researcher designed two drug trials to favor the products of company sponsors. The researcher, Thomas Walsh, an expert on treatment of infections in patients with cancer and immune deficiencies, was also a target of a congressional panel last week looking into how NIH disciplined scientists who broke rules on consulting with drug companies.

    The lead author says the unusual publication is partly a response to a wave of recent media coverage suggesting that clinical trials are “rigged.” “This sensationalism is hurting the process of drug approval and is hurting patients,” says Elias Anaissie of the University of Arkansas for Medical Sciences in Little Rock, who with 108 co-authors published the online commentary in Clinical Infectious Diseases last week.

    In the 5700-word report on 16 July, the Los Angeles Times detailed Walsh's role in leading clinical trials of two new antifungal drugs. The report suggested that doses of the older drugs being compared were too low. It also questioned whether a federal employee should have presented the companies' data to the U.S. Food and Drug Administration.

    The 13 September journal commentary accuses the newspaper of “unfairly malign[ing]” Walsh and “fear-mongering” by suggesting that “the entire process of drug development … is corrupt.” The researchers, 10 of whom co-authored trial publications, say the doses used were the standard of care. A footnote to the commentary describes many of the writers' extensive ties to drug companies. “You can't work in this field and not work with pharma. It's impossible,” says Anaissie.

    A House Commerce subcommittee last week grilled federal officials about why Walsh and another researcher who broke consulting rules are still working at NIH (Science NOW, 13 September, sciencenow.sciencemag.org/cgi/content/full/2006/913/1). Last year, NIH found Walsh guilty of “serious misconduct” for accepting about $100,000 from 25 drug companies without seeking permission or reporting the income. But the congressional panel is not pursuing Walsh's role in the two trials, says spokesperson Kevin Schweers. It is “following the money, not the science,” he says.

  5. CLINICAL TRIALS

    A Shot of Bone Marrow Can Help the Heart

    1. Jennifer Couzin

    For people lucky enough to pull through after a massive heart attack, survival is only the beginning. Many patients later develop heart failure or suffer additional heart attacks. In a bid to improve the health of heart attack survivors, scientists in Germany and Norway have tested a drastic experimental treatment: shooting bone marrow straight into the heart. The hope is that bone marrow cells, which include certain adult stem cells, may trigger formation of new blood vessels, new heart muscle, or send signals to damaged muscle to repair itself.

    Recipe for repair?

    Two studies find that bone marrow (left) improves cardiac function, but a third reported no effect.

    CREDIT: BCC MICROIMAGING/VISUALS UNLIMITED/GETTY IMAGES

    Results of the three trials, which all appear in this week's New England Journal of Medicine, are contradictory, however, revealing benefit in some cases and not others and reflecting both promise and lingering confusion in this nascent field (Science, 9 April 2004, p. 192). One important question is whether certain types of bone marrow cells are more effective in cardiac repair than others—and how they might be working to help the heart. “That's the $100 million question,” says Andreas Zeiher, a cardiologist at the University of Frankfurt in Germany, who led two of the trials.

    Zeiher and his colleagues ran one trial in 204 volunteers who had had a heart attack within the previous week and another in 75 whose heart attack had hit, on average, more than 6 years before. In the trial of new survivors, Zeiher's group offered half of the participants an infusion of their own bone marrow into the affected artery. The others received a placebo injection. The study looked at left ventricular ejection fraction, a measure of the heart's pumping capacity. Four months after treatment, the bone marrow group's ejection fraction was 2.5% better than the placebo group's—a small difference, Zeiher admits, but one bolstered by the suggestion that after a year, the treated volunteers were healthier. Two had died and none had had another heart attack, compared with six deaths and five heart attacks in the placebo group.

    The study wasn't big enough to assess definitively whether these differences were real or occurred by chance. Still, “it shows that there's a therapeutic window that is much larger than we previously thought,” says Douglas Losordo, who is moving from Tufts University in Boston to direct the Feinberg Cardiovascular Research Institute at Northwestern University in Chicago, Illinois. A favored slogan of cardiologists—“time is muscle”—comes from the idea that doctors must treat patients within hours of a heart attack in order to have a measurable effect on their cardiac function, says Losordo.

    Zeiher's second trial, of individuals who, on average, had had a heart attack more than 6 years earlier, was smaller and produced results that were less clear-cut. Those given their own bone marrow were better off, with an ejection fraction that exceeded the control group's by 4.1%. Another group who received similar types of cells culled from their blood, instead of their bone marrow, experienced no benefit. Losordo, who is running a clinical trial that also selects cells from the blood, believes the blood portion failed because too few cells were administered.

    “A lot of people [may] look at these trials and say, ‘The benefit seems to be pretty small,'” says Richard Cannon, clinical director for the division of intramural research at the National Heart, Lung, and Blood Institute in Bethesda, Maryland. Giving him pause, too, is the Norwegian study, led by cardiologists Kolbjørn Forfang and Ketil Lunde of the Rikshospitalet University Hospital in Oslo. “We found no difference” between 47 individuals given bone marrow roughly 6 days after a heart attack and 50 others in a control group, says Lunde. The study was not designed to pick up a disparity of less than 5% in ejection fraction, he notes, a difference he feels is necessary to recommend a treatment as invasive as this one. In all three studies, the treatment appeared safe.

    “We need to move to the next level [in trials], and the next level has to be survival and prevention of heart failure,” says Cannon. Another key question, says Losordo, is what type of bone marrow cells to use. “There's abundant evidence … that not all bone marrow cells are created equal,” he notes. The German team had many more cells that boasted the surface marker CD34, the same one Losordo and others use to mark “stemness.” Whereas Lunde has no plans to pursue the therapy further, Zeiher is looking toward a trial of 1200 patients. “I don't think the data's strong enough to say we should start doing this to everybody,” says Joshua Hare, a cardiologist at Johns Hopkins University in Baltimore, Maryland. “But it clearly substantiates that we should move ahead.”

  6. PALEOANTHROPOLOGY

    Lucy's 'Child' Offers Rare Glimpse of an Ancient Toddler

    1. Ann Gibbons

    After a long, hard labor, a young Ethiopian has delivered a tiny bundle to the paleoanthropological community: the fragile skeleton of a 3-year-old girl buried about 3.3 million years ago in a flood in Ethiopia. At least half of the tot's fragile skeleton is preserved, including the skull with both jawbones attached. It is the “most complete partial skeleton of an early juvenile hominid ever discovered,” exults its discoverer, Ethiopian paleoanthropologist Zeresenay Alemseged of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

    With child.

    Zeresenay Alemseged co-discovered the oldest skeleton of a child in the badlands of Ethiopia.

    CREDITS: DIKIKA RESEARCH PROJECT; (NSET) ZERESENAY ALEMSEGED

    After working for 5 years with dental tools to painstakingly remove cementlike sandstone from the skeleton, Alemseged uncovered enough of the hominid to offer a viewing of it in this week's issue of Nature. Analysis of the freshly exposed skeleton has just begun and the bones of the upper body are still stuck together, but the remains promise to give researchers their first glimpse of a juvenile hominid from head to toe, as well as rare insight into ancient hominid growth and development. Although there are older jaw fragments of children, there are only two other child's skulls dating to more than half a million years ago, including a deformed skull of the same species. “There hasn't ever been a fossil of that antiquity with so many winning cards,” says paleoanthropologist Bernard Wood of George Washington University in Washington, D.C.

    Alemseged was a postdoctoral researcher at Arizona State University's Institute of Human Origins in Tempe in December 2000 when he and Ethiopian antiquities officer Tilahun Gebreselassie found part of the skull protruding from the ground in Dikika, Ethiopia. Over the next 4 years, Alemseged and his colleagues slowly extracted the petite skeleton. It had been buried by floodwaters about 10 kilometers from the resting place of the famous 3.1-million-year-old partial skeleton called Lucy, at Hadar, and turns out to be an earlier member of her species, Australopithecus afarensis.

    As in adults of this species, the child has a mix of primitive, apelike traits and more modern traits such as ankle and knee bones adapted for upright walking. The remarkably complete skeleton includes all the teeth, which were used to determine age and sex, plus rare bones such as shoulder blades and an apelike hyoid bone, only the second ancient voice box bone found. The shoulder bones looked so much like those of a young gorilla that it was a “shock,” says co-author Fred Spoor of University College London. The shoulder blades and long, curving fingers suggest to Alemseged that A. afarensis might have been adapted for climbing in trees. This reignites a long-standing debate over whether this upright species still spent much time in the trees or merely retained ancient features it no longer used, like wisdom teeth in humans.

    Indeed, Carol V. Ward of the University of Missouri, Columbia, an expert on hominid postcranial bones, says that photos of the shoulder bone did not look so apelike to her. And Tim White of the University of California, Berkeley, warns that it is premature to draw conclusions about the fossils' development and locomotion, because the team hasn't yet finished cleaning the rock from the bones.

    Nonetheless, Ward and others predicted that the skeleton would offer an “exciting opportunity” to look at skeletal development and how proportions of limbs and body parts developed in relation to each other and to other fossils. A comparison with the famous 4-year-old Taung child skull of A. africanus, whose species lived 1 million to 3 million years ago in South Africa, might also reveal differences in development.

    The Dikika girl had a small, chimp-sized brain, as expected for her species. But her brain might have grown at a slower rate than in apes—perhaps resembling the slow rate found in humans, says Alemseged. This may be a hint of a more humanlike pattern of development or just a poor diet. Regardless, says Alemseged, at the very least, “now we can say: This is what a baby A. afarensis looks like.”

  7. OCEAN SCIENCE

    Creatures Great and Small Are Stirring the Ocean

    1. Richard A. Kerr

    Explaining the forces that mix things up in the ocean has always been the province of the physical oceanographers. It seemed obvious that physics governs how the winds and tides drive the waters and thus how deep, cold, nutrient-rich seawater is mixed toward the surface. Marine life was clearly just along for the ride.

    But recent evidence suggests that marine life may itself be helping stir the ocean, from local to global scales. “My initial reaction was, ‘Preposterous,'” says physical oceanographer Carl Wunsch of the Massachusetts Institute of Technology in Cambridge. “Then you look at the numbers, and it's not so preposterous. The order-of-magnitude numbers suggest it's worth talking about.” And the implications could be huge. Overfishing of the big whales, for example, could be changing global climate.

    On page 1768, physical and biological oceanographers report that at least one rather small marine creature does indeed stir the ocean, if only a small part of it. Prodded by theoretical claims of substantial biomixing on a global scale, physical oceanographers Eric Kunze, Richard Dewey, and Kevin Bartlett and biological oceanographers John Dower and Ian Beveridge, all at the University of Victoria in Canada, went to Saanich Inlet on the British Columbia coast to take a close look. This fjord's water is stratified, and turbulence there is as low as in the deep, open ocean.

    Saanich Inlet is also home to myriad 1- to 2-centimeter-long, shrimplike creatures called krill. They loiter in the murky depths by day and at night swim up toward the surface under the cover of darkness to feed. So Kunze and his colleagues lowered an instrument package into the path of the migrating krill. The measured turbulence shot up by three to four orders of magnitude for 10 to 15 minutes as the krill passed.

    Oceanic agitator.

    This 2-centimeter krill, Euphausia pacifica, can mix the sea if it teams up with thousands of its kind.

    CREDIT: MOIRA GALBRAITH

    “I'm pleased it isn't all just theory,” says biological oceanographer Mark Huntley of the University of Hawaii, Kaneohe. He and biological oceanographer Meng Zhou of the University of Massachusetts, Boston, had calculated how much mixing a variety of critters—from bacteria to blue whales—might be causing, based on what is known of their size and swimming habits. By Huntley and Zhou's calculations, the turbulent mixing of schooling animals from krill and anchovies to whales “is equivalent to a pretty sustained storm at a local level,” says Huntley.

    Huntley imagines that schools of krill in the stratified Southern Ocean around Antarctica could be stirring water upward with each daily vertical migration, locally replenishing the nutrients depleted by the photosynthesizing phytoplankton. In effect, the swarming krill could be fertilizing the shallow sea, which would boost the production of phytoplankton that are eaten by small zooplankton that feed the krill.

    Grander speculations will appear in the upcoming Journal of Marine Research (July 2006 issue). Physical and biological oceanographers led by William Dewar of Florida State University in Tallahassee calculated how much energy phytoplankton store in new organic matter each year: about 63 × 1012 watts (63 terawatts, or TW). Perhaps something like 1% of that, or almost 1 TW, may go into swimming motions that stir ocean waters, they estimate from expected energy losses and from the amount of oxygen consumed in the ocean.

    A TW of biomixing would be a lot. In 1998, Walter Munk of the Scripps Institution of Oceanography in San Diego, California, and Wunsch estimated that 2 TW of mixing is required to mix deep, cold waters to the surface. That completes the “conveyor belt” circulation of the world ocean, which is vital to the climate system. Dewar and his colleagues speculate that the decimation of stocks of big fish and whales over the past couple of centuries could have removed enough biomixing to have an effect on climate.

  8. ARCHAEOLOGY

    Mad About Pyramids

    1. John Bohannon

    With the violent 1990s behind them, archaeologists in Bosnia hoped they would receive more support for academic research; instead, they are being pushed aside by amateurs

    Human design?

    The hill that looms over Visoko resembles a pyramid.

    CREDIT: MARIO GERUSSI

    SARAJEVO—It should have been a great day for Balkan archaeology. For the first time since the bloody civil war, experts from all corners of ethnically divided Bosnia gathered for an impromptu meeting at the National Museum. Television crews were waiting outside for interviews. Foreign scientists were on hand, too—including the president of the European Association of Archaeologists, Anthony Harding of Exeter University in the U.K.

    But the mood was one of deep frustration. The journalists weren't interested in the scientists' plans for restarting international collaborations. Nor did they want to hear about rebuilding the ailing university curriculum, or saving the country's archaeological assets from neglect and looting. “They only want to hear about one thing,” says Zilka Kujundzic-Vejzagic, the museum's expert in prehistoric archaeology, who organized that 9 June meeting: “pyramids, pyramids, pyramids.”

    The “pyramids” in question are 30 kilometers northwest of Sarajevo near the town of Visoko. A Bosnian businessman named Semir Osmanagic, who runs a construction company in Houston, Texas, announced last year that a 360-meter-tall hill that looms over Visoko is in fact a buried pyramid built, he claims, by an unknown civilization 12,000 years ago. He has dubbed it the Pyramid of the Sun. With the help of volunteers, Osmanagic has uncovered stone blocks beneath the hill's surface and a system of tunnels, which he says are like those of the pyramids in Egypt. Osmanagic has proposed that two smaller hills nearby are part of the same “pyramidal complex.”

    That vision is not shared by any of a half-dozen archaeologists and geologists who spoke to Science after visiting Visoko. The truth is plain, says Stjepan Coric, a Bosnian geologist at the University of Vienna, Austria, who was invited by Osmanagic to examine the site: The stone slabs are nothing more than fractured chunks of sediment called breccia, the remains of a 7-million-year-old lakebed that was thrust up by natural forces. “This is what gives the mound its angular shape,” Coric says. As for the tunnels, “if they were made by humans, without establishing their age, I would assume they are part of an old mine.” Harding's verdict: “It's just a hill.”

    But this humdrum assessment has been swept aside by a pyramid-mania that has gripped the media. Osmanagic, aided by a publicist and an Indiana Jones-style hat, is widely depicted as a maverick bravely pursuing his unorthodox hypothesis. Even the BBC contributed a wide-eyed report in April. The Bosnian public and politicians have fallen deeply under his spell. Archaeologists are concerned that funding for real research projects is being drained away to support Osmanagic's “Pyramid of the Sun Foundation,” and those who voice dissent are receiving hate mail. “To believe in the pyramids has become synonymous with patriotism,” says Kujundzic-Vejzagic. Worse than that, some archaeologists say, Osmanagic is starting to dig up the remains of unstudied human occupation, possibly a long-sought medieval town. “Pyramid-mania” will probably be short-lived, says Harding, but it would be “tragic” if it damaged “real archaeological material.”

    Picking up the pieces

    “Sarajevo was a real center of excellence” for archaeology before the war broke out in 1992, says Harding. But during 4 years of nonstop shelling, “we nearly lost everyone and everything,” says Kujundzic-Vejzagic, who fled to Croatia a year into the conflict.

    Archaeological sites were used as defensive positions in fierce battles, and shattered windows left the museum vulnerable to winter weather and animals. The timing could not have been worse, says Preston Miracle, an archaeologist at the University of Cambridge, U.K., who has worked in the region for 2 decades. Just before the war, he says, “the senior generation of Bosnian prehistorians all died,” and the generation in line to replace them scattered.

    Ten years on, the community still has not recovered, “but at least it is clear what needs to be done to get us back in shape,” says Kujundzic-Vejzagic, who returned in 1998 and has remained at her post in Sarajevo. The first priority is “to assess and protect” the endangered archaeological riches in the country, now known as Bosnia and Herzegovina. This roughly Switzerland-sized territory has been continuously occupied all the way back to the last Ice Age and beyond.

    Little is known about the first Slavic tribes that arrived some 1500 years ago, says Kujundzic-Vejzagic. Even less is known about the people who preceded them, the Illyrians, who held sway from around 1300 B.C.E. until the Romans took over. Learning more about their interactions with neighboring cultures, especially the Greeks, would shed light on the technological revolutions that changed Bronze and Iron Age Europe. “All of these settlements and graves are just waiting to be studied,” she says, although “we'd do better to leave everything in the ground” until resources are secured to protect against weather and looters.

    Deeper in time, fundamental questions about Neolithic society have sustained one of the few remaining international collaborations in Bosnia. Over the past 4 years, a team led by Kujundzic-Vejzagic and Johannes Müller, an archaeologist at the University of Kiel, Germany, has been exploring a site near the town of Okoliste, 7 km away from the pyramid hunt. It has been identified as part of the Butmir culture, a source of richly decorated pottery and intricate statuettes discovered in 1893. Research on these artifacts and related 7000-year-old dwelling sites could help answer one of the central questions of prehistoric archaeology, says Müller: “How and why did we go from simple, egalitarian societies of small settlements to complex, hierarchical societies with big, dense settlements?”

    Buried in the soil near Okoliste are the remains of the largest Neolithic settlement ever found in Europe: between 200 and 300 houses protected by a ring of three trenches and a raised bank. “I was astonished when I realized that this defended area alone could have been home to as many as 3000 people,” Müller says. Settlements from contemporary Neolithic cultures in Europe were occupied by no more than 300.

    Another research team, led by Miracle and Tonko Rajkovaca, a Bosnian archaeologist also at Cambridge, has just begun looking for traces of even earlier human occupation in northern Bosnia; the area is thought to be one of the last refuges of the Neandertals. “Despite the richness of this record,” says Miracle, the region “remains poorly known and understood.”

    With relatively untapped heritage resources, academic archaeologists say, the Bosnian government should be trying to help in any way possible. But instead, many researchers feel that the country is turning against them.

    When hills become pyramids

    If you stand in the right place in Visoko, the largest of the nearby hills almost looks like a pyramid. At least, two of its sides are more or less flat, although the rest is lumpy. During a tour of the site by Science in June, freshly dug earthen stairs led up the slope through the trees, slick with rain. Along the way up, broad patches of soil had been cut away and roped off with yellow tape. A pair of local guides pointed to the exposed crust of fractured rock and explained, “This is the side of the Pyramid of the Sun.” And pointing to two smaller hills across the valley: “That is the pyramid of the dragon, and that one is the pyramid of the moon.”

    Osmanagic, who came up with the hills' mythical names, says he became convinced in April 2005 that they are buried pyramids, based on their shape and position. Osmanagic is in love with pyramids. He says he has studied “hundreds” of them around the world—including the Mayan pyramids, which in his view were located and built with “vibrational” technology inherited from the lost civilizations of “Atlantis and Lemuria.”

    Big dig.

    Semir Osmanagic (in hat) and Ivica Šarić, Sarajevo's minister of culture, with volunteer excavators at the “pyramid” site. Archaeologists worry that valuable material may be stripped away.

    CREDIT: MARIO GERUSSI

    He says he has sought the help of experts to make “serious scientific argumentation.” One of the first was Amer Smailbegovic, a geophysicist who runs a surveying company and teaches at the International University of Sarajevo. “I noticed that the area has a peculiar triangular-sided feature you don't see too often in a temperate environment,” says Smailbegovic, who analyzed satellite imagery for Osmanagic. Thermal and radar imaging also made the hill seem “out of the ordinary,” he says. So Smailbegovic wrote to Osmanagic that “there are anomalies present in your area of interest, and you may have something there. I suggest you find yourself an archaeologist and geologist to help you validate the area.” But “the next thing I know,” Smailbegovic says, “there was a headline in the Bosnian papers: Satellite imagery confirms Osmanagic's discovery of pyramids in Bosnia.” This would prove to be the start of a barrage of “sensationalism,” he says.

    Osmanagic says he invested $20,000 of his own money to hire dozens of people, including a public relations manager, and established a tax-exempt foundation to pay them. He also placed an advertisement in the listings of the Archaeological Institute of America for someone who could do Paleolithic fieldwork. Among those who responded was Royce Richards, an archaeologist who works for the Australian government as a heritage officer in Adelaide.

    In January, “things got very strange,” says Richards. In newspaper articles around the world, he was named as one of the main “expert advisers” on an international dig that has discovered “evidence of Bosnian pyramids.” Osmanagic's foundation Web site had included Richards in the “advisory committee of experts,” even though he never visited Bosnia nor confirmed that he would participate. Other academics say they were listed although they had never asked to be involved. One of them, Bruce Hitchner, head of the archaeology program at Tufts University in Medford, Massachusetts, objected when he learned that his name had been hijacked. Osmanagic has removed all the expert advisers' names from his Web site but says, “I did nothing wrong.”

    Smailbegovic visited Visoko in April to see the project for himself. “The situation was chaotic,” he says. Osmanagic's volunteers are digging up the area, but Smailbegovic didn't see much effort directed at “answering the question of why there are geospatial anomalies in the Visoko valley.” Smailbegovic and other geologists conducted their own field study of the Visoko valley in May and June. He says Osmanagic has ignored their detailed reports, which conclude that natural forces created “the majority of the landscape features” and that “meticulous archaeological work” is needed to determine whether humans had any part in it.

    Osmanagic says he is doing just that, but archaeologists are outraged. “This is the equivalent of letting me, an archaeologist, perform surgery in hospitals,” says Enver Imamovic of the University of Sarajevo, a former director of the National Museum. By assuming that the hills are pyramids from the very start, says Müller, “that's all he'll ever see.” For example, he points out, Osmanagic's deduction of the age of the pyramids at 12,000 years old is based on nothing more than the depth of the soil over the stones that he claims are masonry. While clearing away that soil, Osmanagic's volunteers have found engraved stones and a skeleton. Imamovic worries that these may be signs of a long-sought necropolis or a lost town mentioned in Byzantine texts. Osmanagic says the skeleton “is being analyzed,” but he believes it was recently interred.

    Osmanagic also says he has uncovered a stone layer that is “the pyramid's face” on one of the smaller hills. A European archaeologist working in Bosnia who had a look for himself says, “There is a real wall there, but it looks to me like part of a small Middle Age rain reservoir.” The archaeologist, who requested anonymity for fear of losing permission to work in the country, says he is not surprised that diggers have uncovered signs of human occupation: “People have been here for millennia.” But after Osmanagic is done with Visoko, “we may never know what was really here,” he says. The real archaeological material is between the surface and the bedrock, he says, “but for a pyramid-hunter, that is just dirt to strip away.”

    Osmanagic says he is aware that he is digging through layers of occupation and claims he will publish his results “in a peer-reviewed journal” in November. “But I am not interested in the approval of elite scientists. This project is for the people.”

    Popular archaeology

    In spite of the protests from academic quarters, public and political support for Osmanagic seems to be growing. The government has granted him all the necessary permits and has even helped finance his excavations. “It is shocking” that public funds are flowing to Osmanagic instead of the country's desperate archaeologists, says Müller. But Osmanagic says that only 10% of his current budget—the total is about $300,000, he says—comes from government support, while the rest is from “private funds and corporate sponsors.”

    One expert says it's easy to understand why people seeking a national identity would embrace the Visoko phenomenon. “Osmanagic's pyramid fantasies are exactly what the majority of Bosnians want to hear,” explains a Bosnian sociologist who spoke on condition of anonymity. There are also economic motivations. Last month, Osmanagic announced plans to build three “archaeological parks” across the country that will “rewrite world history” by revealing more evidence of Bosnia's prehistoric “supercivilization.” New highways and hotels are part of the plan.

    Crude as it may seem, pyramid-mania could be a boon over the long term, says Miracle: “If the energy and interest in archaeology can be redirected into Bosnia's rich heritage, then this affair would not be such a fiasco after all.” But few are optimistic. Kujundzic-Vejzagic says she is on the verge of quitting. She says she's been the target of hate mail from the pro-pyramid movement; no one in government has stepped forward to defend her. If she goes, the entire Butmir project will probably fold, says Müller. “There is no other prehistoric archaeologist in the country,” he says. “She is our only partner.” Bosnia's other archaeologists are in an equally precarious position. A Visoko municipal official recently announced that all critics of Osmanagic's project should be denied access to research locations and have their degrees revoked.

    The real thing.

    Archaeologist Zilka Kujundzic-Vejzagic holds a pot from the Butmir culture that flourished in Bosnia 7000 years ago.

    CREDIT: J. BOHANNON/SCIENCE

    Descending the hill back down to Visoko, a visitor wades through the friendly locals selling official “Pyramid of the Sun” T-shirts and mugs. One thing is clear: Some people will benefit from the hunt for a prehistoric Bosnian civilization. But they may not be academic archaeologists.

  9. SCIENTIFIC WORKFORCE

    Frustrations Mount Over China's High-Priced Hunt for Trophy Professors

    1. Hao Xin*
    1. 1With reporting by Dennis Normile.

    Chinese universities bask in the glow of top-gun scientists hired on part-time deals to share their wisdom. Critics say the money could be spent more wisely

    Mathematician Gang Tian did not expect a standing-room-only crowd last week when he gave a lecture at Beijing University (Beida) on the Poincaré conjecture. But not all were there for the math. Reporters and others had come for a glimpse of the man at the center of a tempest engulfing Chinese academia. Tian is a premier example of a controversial phenomenon: a Chinese-born researcher with a full-time faculty position overseas who gets paid handsomely for short working stints in his homeland.

    Resentment against part-timers boiled over last July, when Shing-Tung Yau, a Harvard University mathematician and Tian's former mentor, dismissed the “majority” of Beida's overseas recruits as “jiade,” or “fakes,” in comments in the Chinese magazine Nanfang Renwu Zhoukan. Beida officials fired off a series of rebuttals in which they termed Yau's remarks “irresponsible” and a “distortion of facts” and rattled off achievements—papers in prestigious journals and patents, for instance—by talent returned from overseas.

    The university's attempts at damage control, however, only intensified debate about professors such as Tian, who has been listed among Beida's full-time faculty for several years. Beida nominated Tian to membership in the Chinese Academy of Sciences (CAS), an honor reserved for scientists who expend at least half their effort in China. Thanks to Beida's backing, Tian—who was then also listed as a full-time professor at the Massachusetts Institute of Technology (MIT)—was elected in 2001 by a margin of one vote. Last spring, Tian left MIT to become a full-time professor at Princeton University.

    After the Poincaré lecture, reporters pressed Tian about his employment status in China. He said that he now spends more than 4 months a year at Beida and “hopes to be a full-time professor later on,” perhaps after Beida builds a $13 million international institute of mathematics, which Tian will direct.

    Some proponents consider part-time academic appointments a critical means of stanching China's loss of scientific talent. Universities and government agencies are boosting quotas for part-timers and upping the ante to entice more top guns to return. Several universities have created “million-yuan professorships” with stratospheric—for China—annual salaries equivalent to $125,000. Most returnees are midcareer scientists who accept more modest offers (see sidebar on p. 1722).

    Critics, however, contend that part-timers often are less important as professors than as tools in the battle for prestige and resources. Yau claims that researchers who parachute in can hardly contribute in a substantive way to China's scientific development. But the trend seems almost unstoppable, says Shigang He, a neuroscientist currently at CAS's Institute of Biophysics in Beijing: “I don't think universities will really seriously control this, because they benefit.”

    A call for oversight.

    Shigang He thinks China's funding agencies should hold part-time professors to their contractual commitments.

    CREDIT: COURTESY OF SHIGANG HE

    Offers too good to refuse?

    Overseas academics began returning to China in the late 1990s, drawn by programs to woo talented scientists back (Science, 21 January 2000, p. 417). The Ministry of Education's Changjiang Scholars Program and CAS's One-Hundred-Talent Plan intended initially to recruit people to work at least 9 months a year—essentially full-time—in China. But top-notch researchers who signed up wanted to help their homeland and keep their jobs overseas: “If you have a tenured professorship [in the United States], it does not make sense to give up the position,” says Jun Liu, a statistician at Harvard.

    The education ministry quickly took a new tack, creating a category of part-time Changjiang scholars: jiangzuo, or lecture chairs, for associate professors or higher. They are required to spend no fewer than 3 months—or two, “under special circumstances”—in China. But universities eager to attract stars are willing to make exceptions. Ying Xu, a bioinformatics researcher at the University of Georgia, Athens, says he turned down a couple of invitations to apply for a jiangzuo post, citing time constraints. University officials have told him that a 3-month commitment could be met by arriving at the end of the first month and leaving at the beginning of the third—but Xu says “his conscience did not allow” him to play that game. (Such overtures, other scientists say, are typical.) Xu chose instead to organize a weeklong symposium in China each summer.

    Other part-timers say they are unaware of a time requirement. Liu accepted a jiangzuo post at Beida in 2002, but he acknowledges that he spends only about 1 month a year in China. Gary Becker, a Nobel laureate in economics at the University of Chicago in Illinois who recently joined Beida as a Changjiang jiangzuo, says, “What I will do is not precise; it will be mainly up to me.”

    Incentive programs have stirred controversy before. CAS began a crackdown after an open letter in 2003 publicized one extreme case of a full-time researcher then at the University of Wisconsin who held grants from three programs and fulfilled a pair of 9-month and one 6-month commitments concurrently. According to CAS's Li Hefeng, the academy so far has canceled the awards of 166 recipients (out of 1005 overseas recruits) and demanded the money back.

    Despite allegations that the system is rife with cheating, universities covet part-timers and have lobbied for an expansion of the programs. In 2004, the education ministry raised its annual quota of jiangzuo from 10 to 100. Last year, Beida for the first time appointed more Changjiang part-time (11) than full-time professors (10). Many universities have set up their own programs for illustrious part-timers—“Nobel laureates” and “internationally famous scholars,” as Zhejiang University's announcement puts it. Whereas Zhejiang is still hoping to snare a Nobel laureate, Beida, in rebutting Yau, touted three among its jiangzuo ranks: “One can well imagine their contributions to education and research,” the university stated.

    A fair compromise?

    Many academics feel that the prestige that comes with hiring part-timers is superficial. “Some high-profile papers appear to come from China, even though the science didn't really take root [there],” says Mu-Ming Poo, a neuroscientist at the University of California, Berkeley. Chinese universities turn a blind eye to absentee professors as long as they list their Chinese affiliation on papers, adds He.

    Buying spree.

    Top Chinese universities are sharply increasing their ranks of part-time researchers from overseas, even as numbers of full-time returnees hold steady.

    View this table:

    Indeed, the number of publications with Chinese authors listing multiple affiliations is on the rise. For example, Zhong Lin Wang, a nanotechnology researcher at Georgia Institute of Technology in Atlanta, has three affiliations on recent papers in Science: Georgia Tech, Beida, and the National Center for Nanoscience and Technology in Beijing. Wang is part-time director at both Chinese institutions, which hailed his publications on their Web sites. Wang acknowledges that the work was done solely at Georgia Tech. Similar cases abound.

    At the same time, some part-timers downplay their moonlighting. Zhensu She, a mathematician at the University of California, Los Angeles, lists in his CV on UCLA's Web site his full-time Changjiang professorship at Beida as an “award” in 1999—it was a 5-year contract—and does not mention that he is director of the Key State Laboratory of Turbulence and Complex Systems and deputy director of the Center of Theoretical Biology, both at Beida.

    UCLA policy states that “compensated teaching or research at another institution while employed as a full-time faculty member” requires “prior written approval of only the Chancellor or Executive Vice Chancellor.” As Science went to press, UCLA had not clarified whether She or seven other faculty members with similar positions in China obtained such approval. She did not respond to requests for an interview; a source in UCLA's math department says he is on sabbatical.

    Teaming up—or outsourcing?

    To many Chinese scientists, the bottom line is not how much time is spent on Chinese soil but whether one contributes to the country's science. Poo helped create the Institute of Neuroscience (ION) in Shanghai in 1999 and since then has been its part-time director. He views his role as enabling young Chinese scientists to gain international recognition based on their own projects and publications. Although Poo spent about 80 days in Shanghai last year, and ION covers his expenses, he does not receive an ION salary. “I do not have any problems with people like Mu-Ming Poo,” says He. “He is really dedicated, working hard, and doing a good job.”

    But critics maintain that part-timers such as Poo are rare; many appear to leverage their own projects by taking advantage of China's abundant student labor. In the late 1990s, Xingwang Deng, a molecular biologist at Yale University, proposed using Beida's “human resources” to search for all the genes of the model plant Arabidopsis. The idea appealed to Gu Xiaocheng, a senior biologist, and Chen Zhangliang, then a Beida vice president; the university provided lab space and seed funds. At Yale, Deng taught a young Beida scientist, Qu Li-jia, how to make Arabidopsis mutants.

    For his efforts, Deng was appointed a 9-month Changjiang professor by Beida, although he made clear he could not work full-time in China. To reconcile his commitments to Yale and Beida, Deng came up with a “win-win solution,” says Gu: Deng persuaded Yale and Beida to establish the Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology. Under Deng's directorship, the center has been generating data for the Arabidopsis Mutants Database and papers, most of which list Deng as senior author.

    Provocateur.

    Tempers flared after Harvard's Shing-Tung Yau asserted that the majority of Beijing University's overseas recruits are “fakes.”

    CREDIT: CONAN LEUNG

    Given China's “low level” of science, Gu says, this kind of arrangement can be beneficial. “You may call it outsourcing,” she says, but the resulting exchanges might not have happened otherwise. Qu adds that before the Peking-Yale Center was set up, “we did not even know how to grow Arabidopsis, but now seven labs at Beida do related work.”

    Other part-timers are following Deng's example. In 2002, Tian Xu, a Howard Hughes Investigator at Yale and a Changjiang jiangzuo at Fudan University in Shanghai, created the Fudan-Yale Biomedical Research Center, which now employs 20 grad students, one postdoc, and more than 40 staff to screen for genes in fruit flies and mice. And UCLA's Shuo Lin, a Changjiang jiangzuo at Beida since 2004, has retained a dozen grad students there to trawl for zebrafish genes.

    With these successes, China seems unlikely to wean itself of its part-timer dependence anytime soon. CAS is even spawning a new breed: “innovation teams” including five or six senior academics from abroad who will take turns spending a year in China and share a pot of $750,000 for research.

    But Yau and other critics insist that the popularity of these programs does not justify the expense. Rather than lavish money on part-time academics, they argue, Chinese institutions should raise stipends of students and young researchers from their present paltry levels of $30 to $160 a month. “The Chinese government does not pay enough attention to young people,” Yau says. As long as the brightest young minds seek greener pastures outside China, the brain drain—and the hunger for overseas talents—will continue.

  10. SCIENTIFIC WORKFORCE

    Many Overseas Chinese Researchers Find Coming Home a Revelation

    1. Dennis Normile

    SHANGHAI—” When I left China to study abroad, I thought I had left China for good,” says neuroscientist Shigang He. Yet, after earning his Ph.D. and landing a permanent research position in Australia, He started having second thoughts. A visit to a Chinese institute astounded him. Labs were bulging with new equipment and feverish with activity. And funding for individual researchers was nearly on a par with his in Australia. He made several trips back to China, he says, “to make sure I wasn't deluded.” Then he did something once unthinkable for a Chinese scientist established abroad: He resigned from the University of Queensland, sold his house in Brisbane, and joined the Institute of Neuroscience in Shanghai, a part of the Chinese Academy of Sciences (CAS).

    “I've never regretted it,” says He, who is now with the CAS Institute of Biophysics in Beijing. “For my research, and personally, it was a good decision.”

    He's not alone. Although numbers are hard to come by, repatriated scientists are multiplying. Officials at the Institute of Health Sciences, a part of CAS's Shanghai Institutes for Biological Sciences (SIBS), say a third of the two dozen primary investigators who have joined the institute since its founding 4 years ago had given up permanent jobs overseas. “It is definitely a new trend, not only at SIBS but throughout China,” says SIBS President Gang Pei.

    Those returning to their roots say the trend indicates how far Chinese science has come in catching up with the West. “It is no longer true that a faculty position in China is less competitive than one in the U.S.,” asserts Jianmin Zhou, a molecular plant biologist who left an associate professorship at Kansas State University, Manhattan, for a position at the National Institute of Biological Sciences in Beijing. In China, midcareer returnees bridge a gap between young scientists trained abroad and high-profile veterans who spend a few months a year in China as advisers. “These midcareer people help China” with their experience and administrative skills, says Pei.

    The returnees so far, however, are not superstars. Few “are from first-tier universities and/or doing first-rate work,” says Li Jin, a population geneticist who relinquished a full professorship at the University of Cincinnati to become dean of life sciences at Fudan University in Shanghai. And returnees spurn offers from any but the top institutions in cosmopolitan Beijing and Shanghai.

    Making a choice.

    Population geneticist Li Jin gave up a U.S. tenured professorship to become dean of the School of Life Sciences at Fudan University.

    CREDIT: COURTESY OF LI JIN

    Deciding to come home usually starts with a realization of how quickly the research landscape in China is improving. “Support for research by most agencies in China doubled this year,” says Jin. “The pressure for getting grants [abroad] is one of the major reasons that drives people back to China.” The funding now offered a new scientist to set up a lab in China roughly matches that of a U.S. university, adds He. Individual grants may be smaller, but money goes further in China too. Scientists also rave about the quality of students. “Many Chinese faculty … have better students than their peers in the U.S.,” says Zhou. Part of the appeal is helping shape China's science future. Guo-Tong Xu, once an assistant professor at the University of North Texas Health Science Center in Fort Worth and now deputy director of SIBS's Institute of Health Sciences, boasts that his institute is the first in China dedicated to translational research, bridging the gap between basic and clinical research.

    Some scientists return to pursue opportunities that are illegal or not encouraged in the United States and other countries because of ethical concerns. Hui Zhen Sheng returned in 1999 after 10 years at the U.S. National Institutes of Health when the Shanghai government made an offer “too good to decline”: to fund a stem cell lab for her at Shanghai Second Medical University. Sheng is working on therapeutic cloning of human embryonic stem cells using animal eggs.

    Similarly, stem cell research brought Hongkui Deng back. Deng left China in 1989 to study immunology at the University of California, Los Angeles, and later became research director for ViaCell Inc., a biotech firm in Cambridge, Massachusetts. Finding the corporate world “quite restrictive,” Deng in 2001 joined Beijing University, where he is trying to coax human embryonic stem cells to differentiate into beta cells for treating diabetes. “Stem cell biology is a new field, so China is at the same starting line as everybody else,” says Deng.

    Some scientists try to keep a foot in both worlds, before deciding that China is where they want to be. In 1997, Jin set up a field station at Fudan, his alma mater, to collect DNA from China's diverse populations. In 2003, he was made dean and began splitting his time between continents. “It was really stressful to maintain two laboratories,” he says. In 2005, Jin resigned from Cincinnati and moved with his family to Shanghai.

    There are downsides for midcareer returnees. Salaries are smaller, for example, although a low cost of living can compensate. And whereas Chinese universities grant tenure to all faculty members, at many CAS institutes new researchers must pass reviews after several years before getting a permanent job, even if they gave up a tenured position in the West.

    Middle-aged scientists also typically have families to consider. Xu recalls that his elder son had a tough time adjusting to fifth grade when the family returned from the United States in 1997. Xu's colleague, geneticist Ji Zhang, who gave up a tenured job at the University of Nebraska Medical Center in Omaha in 2002, left his wife and 17-year-old son in the States so the boy could continue his education there. “It would be difficult for my son now to adapt to life in China,” Zhang says.

    Lifestyle issues cut both ways. Jin says, half-jokingly, that he returned for the food. The best Chinese restaurants in Cincinnati can't match Fudan's student cafeteria, he notes. On the other hand, he and his family squeezed into an apartment one-tenth the size of their Cincinnati home. “I've been trying to convince my kids that it's not quite right for just a few people to have lived in such a big house,” he says. For Jin and other midcareer returnees, cramped apartments are a small price to pay for big opportunities in China's growing research enterprise.

  11. ORNITHOLOGY

    The Pink Death: Die-Offs of the Lesser Flamingo Raise Concern

    1. Robert Koenig

    Researchers are investigating whether mass bird deaths are linked to environmental changes in East Africa's lakes

    CREDIT: TIM DAVIS/GETTY IMAGES

    NAIROBI, KENYA—An aviator once described Lake Nakuru as “a crucible of pink and crimson fire,” with a million flamingos painting an astonishing band of color that burst into pieces as the birds took flight. Such breathtaking scenes still exist in East Africa, but large numbers of its Lesser Flamingos have been dying mysteriously at Nakuru and other naturally alkaline Rift Valley lakes where they feed.

    In recent months, more than 30,000 of the birds have been found dead at Nakuru, leaving enough pink carcasses to spur a newspaper to describe the lake as a “flamingo death camp.” Two years ago, 43,800 of the birds perished at Tanzania's Lake Manyara, the first major die-off at that alkaline, soda-rich lake. Previous mass die-offs occurred at Lake Nakuru and two other Kenyan lakes in 1993, 1995, and 1997, as well as at two lakes in Tanzania in 2002. At the same time, birds have been gathering in places they have never been seen before. This month, thousands of Lesser Flamingos suddenly appeared at small Lake Oloiden in Kenya for the first time.

    As scientists investigate what is behind the deaths and shifts in feeding sites, conservationists are worried about possible new threats from human activity that could degrade the birds' primary breeding site: Tanzania's otherworldly Lake Natron. The remote halophytic lake—whose hot, caustic waters provide a perfect nesting sight for flamingos and protect them from predators—has been proposed as site of a new baking-soda plant whose pipeline “could have quite a disastrous effect on [Natron's] water levels, which are critical for successful breeding,” warns ornithologist Neil Baker, who heads the Tanzania Bird Atlas project.

    Next week, two dozen of the world's leading flamingo experts will gather at a workshop in Nairobi to draft an action plan to protect the Lesser Flamingo species (Phoeniconaias minor). They plan to submit their recommendations to the member governments of the African-Eurasian Migratory Waterbird Agreement and the Convention on Migratory Species, which—if approved—could lead governments to take new measures.

    Occasional flamingo die-offs occur naturally and are not necessarily alarming. But ornithologist Brooks Childress, who will chair the meeting, warns: “What is worrying is that the frequency of the [die-off] events appears to have increased markedly in recent years, even in relatively pristine lakes. We need to find out what the cause might be.”

    Suspect toxins and pathogens

    Snapping on rubber gloves, German phycologist Lothar Krienitz sloshes across the muddy shore of Lake Oloiden toward a clump of pink feathers. As his hip boots sink into the muck, he reaches out a pole and hooks the flamingo carcass for later dissection and tissue sampling. Then he moves slowly to the water's edge and takes samples of the lake water with its abundant greenish growth.

    Krienitz, a research associate with the Leibniz Institute of Freshwater Ecology in Berlin who collaborates with researchers at Kenyatta University in Nairobi, has been sampling the alkaline waters of the Kenyan flamingo lakes since 2001 and looking for changes in salinity, cyanobacterial species, toxins, and other factors that might explain flamingo die-offs. His institute also analyzes the flamingo tissue samples for evidence of fatal toxicity.

    “There are strong indications that cyanobacterial toxins are contributing to the mass flamingo deaths,” Krienitz says, cautioning that the poisonous substances, including the neurotoxin anatoxin-a as well as several liver toxins, may be only one of several explanations for the die-offs. He and others argue that shrinking lake levels and changing salinity have led to a different mix of cyanobacteria, some of which produce toxins that can kill the pink birds.

    Inyasi Lejora of Tanzania National Parks says that scientists at the University of Dar es Salaam's aquatic sciences faculty are convinced that the massive flamingo die-offs at Lake Manyara in 2004 were caused by “cyanobacterial toxins.” But Lake Nakuru's senior research scientist, Apollo Kariuki, says an analysis of bird tissues by Kenya's National Veterinary Laboratory implicates a pathogenic bacterium, Pseudomonas aeruginosa, in the current die-off. Other experts questioned that conclusion and called for further studies of algal toxins.

    Lesser Flamingos, the smallest but most numerous of the world's six flamingo species, are notoriously selective in their feeding habits. They fly from one Rift Valley soda lake to another to find abundant sources of their primary food: a cyanobacterium called Arthrospira fusiformis, which the birds scoop into their filtering bills.

    Ecologist David Harper of the University of Leicester, U.K., who leads the Earthwatch Institute's Lakes of the Rift Valley project, believes the emergence of cyanotoxins as well as the apparent increased vulnerability of the flamingos to disease are both linked to environmental changes in Rift Valley lakes. Water diversion has lowered several lakes' volumes, while pollutants and a host of alien flora and fauna have changed their ecology.

    Other theories about the causes of the flamingo die-offs abound; various scientists have attributed the mass deaths to avian tuberculosis or cholera, botulism, heavy-metal pollution, pesticide runoffs, or combinations of such factors. Childress—global coordinator of the Flamingo Specialist Group, associated with both the World Conservation Union's Species Survival Commission and Wetlands International—suspects that toxins are responsible for killing the birds, perhaps by making them more susceptible to infectious diseases.

    Veterinary microbiologist Lindsay Oaks of Washington State University, Pullman, who helped solve the mystery of Gyps vulture die-offs in India and Pakistan 2 years ago (Science, 16 June 2006, p. 1591), says “systematic and more comprehensive investigations” are needed to determine what is killing the flamingos. Val Beasley, a veterinary toxicologist at the University of Illinois, Urbana-Champaign, who helped organize a 2004 symposium on flamingo die-offs, agrees that more research is needed “to determine if algal toxins, metals, or other stressors weaken the birds so that infections become more widespread and more lethal.”

    Hot water

    The highly alkaline Lake Natron, whose waters can reach temperatures as high as 41°C, is so remote that it was not until 1954 that biologist Leslie Brown discovered that it was the only regular breeding ground for Lesser Flamingos in East Africa. That remoteness, as well as the fact that few predators brave the hot, caustic waters to attack the chicks, may be a primary reason why the flamingos flock to Natron to breed on islands of dried mud. The birds breed infrequently—some estimate once every 5 years—and when chicks mature, they fly off to feed in other lakes.

    Conservationists worry that Natron, which is not in a national park, could be damaged if two development projects succeed: a proposed large plant that would harvest and pipe away the valuable soda, and separate plans to build several tarred roads, making the area more accessible to hunters and tourists.

    The proposed soda plant at Lake Natron would likely be a modern version of the current plant at nearby Lake Magadi in southern Kenya. In 1962—in what may have been the only major breeding event of East African Lesser Flamingos outside of Lake Natron in the last half-century—some of the birds for unknown reasons tried to breed in Lake Magadi with disastrous results. The lake water levels receded so quickly because of drought that soda deposits congealed on the legs of the vulnerable chicks, killing many; others were saved by a rescue effort.

    Jasson John of the Wildlife Conservation Society of Tanzania, a nongovernmental organization, does not draw parallels with Lake Magadi but worries that “a large soda plant at Lake Natron might interfere with the water levels and other ecological conditions of the lake.” John was among the 20 Tanzanian flamingo experts, wildlife officials, tourist industry representatives, and scientists who gathered last month in Dar es Salaam to evaluate the nation's flamingo population and discuss conservation plans that will be presented at next week's meeting of international flamingo specialists in Nairobi.

    One big challenge for them is to agree on the population of Lesser Flamingos living in East Africa. Estimates have ranged from about 1.5 million to 4 million, but the census is complicated by the birds' night movements between alkaline lakes as well as the fact that Tanzania counts it birds at a different time than does Kenya. The species is classified as near-threatened because it is dependent on a very small number of unprotected breeding sites and has stringent limitations on its breeding conditions.

    Childress, who has tracked several Lesser Flamingos using satellite transmitters, says scientists do not know exactly why the birds move so often from one location to another, but the search for food is not the only explanation. “The tagged birds often left a location with plenty of cyanobacteria, leaving hundreds of thousands of other Lesser Flamingos still at the location and still feeding normally,” he says.

    Lately, it seems that some of the flamingos have been behaving almost like tourists, visiting new places along the Rift Valley. Earlier this month, Harper stood on the shore of Lake Oloiden and marveled at the sudden arrival of several thousand Lesser Flamingos—the first time in his dozen years of studying in the region that the birds have appeared there. Krienitz's measurements this month confirmed that the shrinking of the lake has led to higher salinity, which in turn has nourished cyanobacteria, attracting flamingos.

    Sleuth.

    Knee-deep in mud, Lothar Krienitz collects a dead flamingo for tissue sampling at one of Kenya's Rift Valley lakes.

    CREDIT: DORIS KRIENITZ

    Although East Africa has by far the largest population of Lesser Flamingos, there are also smaller colonies in West Africa and southern Africa. In Botswana, ornithologist Graham McCulloch lists disturbance from tourists—including low-flying aircraft—among the potential threats to the breeding of the colony of about 150,000 Lesser Flamingos in the Sua Pan area. But the birds' status as an undeniable tourist draw also may work in their favor. Even if governments are slow to respond to environmental or scientific arguments, concerns about tourism, a leading industry in Kenya, Tanzania, and Botswana, may compel actions needed to preserve and protect the flamingo. Before any such measures can be taken, however, scientists must first solve the mystery of what is killing these exotic birds, whose feathers have brought astonishing hues to the Rift Valley Lakes for millennia.

  12. MANTLE DYNAMICS

    Rising Plumes in Earth's Mantle: Phantom or Real?

    1. Richard A. Kerr

    Seismologists probing the planet's depths are generating tantalizing images, but whereas some researchers see signs of plumes feeding volcanic hot spots, others see noise

    Almost half a century after the plate tectonics revolution, geoscientists still have a hangover. By 1970, a decade or two of geophysical observation beneath the world's oceans had ushered in jostling plates and sinking slabs. But plate tectonics can't explain mid-plate volcanic centers such as Hawaii, and a hypothesis proposed in 1972—that hot rock rises in narrow plumes through the mantle to stoke such hot spots—still gets a mixed reception. “The existence of plumes is controversial to some and old hat to others,” geophysicist Norman Sleep of Stanford University in Palo Alto, California, recently noted. “Skeptics are justified in demanding deep evidence for a deep-mantle hypothesis.”

    The latest evidence from the deep—pictures of the interior painted with seismic waves—is stirring up a field in which such tomographic results have often been disputed. At the same time, geological and geochemical studies are bringing some putative plumes into question (Science, 8 September, pp. 1394 and p. 1426). The new imaging will not calm the turmoil anytime soon, but it is forcing seismic tomography researchers to grapple with the limitations of their tools.

    The hubbub in global seismic imaging started when a group of Princeton University seismologists introduced a new analytical tool to sharpen their view. The problem with plumes has been that according to theory they would be narrow, perhaps a couple of hundred kilometers across at most. A hot plume would slow the part of a seismic wave that passes through it from an earthquake to a seismometer. But the slowed segment of the wave—which in a tomographic analysis would paint a splotch of warm mantle in the image—could then “heal” before ever being recorded, much as an ocean wave can reform after passing around the piling of a pier.

    So Raffaella Montelli, then a graduate student at Princeton and now at ExxonMobil in Houston, Texas; her Princeton adviser Guust Nolet; and theoretical seismologist Anthony Dahlen of Princeton developed a way of analyzing seismic data that for the first time takes account of such wave behavior. In their version of “finite-frequency” analysis, Montelli and colleagues were able to combine so-called P (for primary) seismic waves of two frequencies to form an image of the global mantle from a high-quality data set. Where others had reported nothing more than a debatable plume or two beneath Hawaii and Iceland, the Princeton group saw plumes of varying height beneath most of the classic hot spots, 32 plumes in all (Science, 5 December 2003, p. 1643).

    With the proliferation of plumes and the introduction of a radically new technique, the plume debate only intensified, so Montelli and colleagues have gone one step further. In a paper in press in Geochemistry Geophysics Geosystems, they report how they formed a new global image from S (secondary) waves rather than P waves, again using their finite-frequency technique. S waves—which have a shearing or twisting action—react differently to variations in rock temperature and composition than do P waves, which are compressional, like sound waves. But almost all of the plumes they saw in the P-wave image they also found in the S-wave model. “There is remarkable agreement,” says Nolet.

    A deep plume?

    Extra-hot rock (red and yellows) appears as deep as 2000 kilometers beneath the Galápagos Islands in images generated from either P seismic waves or S seismic waves.

    CREDIT: R. MONTELLI ET AL., GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS (2006 BY THE AMERICAN GEOPHYSICAL UNION)

    The geophysics community's reaction has been mixed. “I must say I found it striking that with both S and P they do get very similar images for some of the plumes,” says theoretical seismologist Jeroen Tromp of the California Institute of Technology in Pasadena. To some others, the picture is much fuzzier. “There are similarities, but many differences too,” says seismic tomographer Rob van der Hilst of the Massachusetts Institute of Technology in Cambridge. And tomographer Adam Dziewonski of Harvard University simply says that “it's difficult to argue these things are real” in either P or S renditions.

    A fundamental problem, say many researchers, is a dearth of data. Everyone agrees that some finite-frequency technique is the way to go, but many argue that even it is being overwhelmed by the limited data available. Most earthquakes that seismically light up Earth's interior fall around the Pacific's Ring of Fire, whereas the seismometers recording them are limited to the continents and a few islands. So even data sets drawing on millions of quake recordings leave parts of the mantle largely in the seismic dark. As a result, “there are infinitely many [tomographic] pictures of Earth that all satisfy the data,” notes Nolet.

    To sort out which picture is the most likely one, the analyst must twist some knobs on the procedure to sharpen the picture while keeping things physically realistic. “This is sort of like reading tea leaves,” notes Dziewonski. And methods for quantitatively gauging how well the final picture can explain the data are still severely limited by computer power. “Interpretation of tomographic models [of the mantle] is a high-risk operation,” concludes Dziewonski.

    To reduce the risk, researchers, predictably, call for more and better data. New seismometers are filling gaps in coverage, but it's taking longer to incorporate new kinds of data from existing seismic records. Most observers see another 5 to 10 years before they'll be able to say with confidence whether plumes exist after all.

Log in to view full text