News this Week

Science  30 Apr 2010:
Vol. 328, Issue 5978, pp. 554
  1. Social Science

    Survey to Reveal True Face of Chinese Society

    1. Mara Hvistendahl*

    For decades, social scientists looking for figures from China were hamstrung. The Chinese government collects copious data, but much is secret, and what isn't classified is often unreliable. The imperfect solution, more often than not, has been for researchers to go knocking on doors themselves.

    This approach changed this month as scores of interviewers dispersed across China for the start of a study that aims to document everything from emotional stress to family planning (see table). They expect to reach 60,000 respondents in 25 provinces—making the survey the largest undertaking of its kind in the developing world. “This is just mammoth compared to other studies,” says Robert Hauser, a demographer at the University of Wisconsin, Madison, who advised the survey's designers.

    The Chinese Family Panel Studies, as the project is called, should provide abundant fodder for data-starved social scientists hoping to track how China's rapid development is shaping societal values, says Yu Xie, a sociologist at the University of Michigan, Ann Arbor, and Peking University who designed much of the new survey. Through this year's baseline survey and annual follow-up visits, he says, “we are going to be able to document some of the biggest changes in history.”

    The $8.8 million survey is broad as well as deep. Comparable U.S. efforts are often funded by government agencies seeking specific data, and as a result they home in on specific age groups or topics. The government-backed Chinese survey, by contrast, was crafted by scholars to fill myriad holes in social science data, meaning it will expand the body of information on China in one fell swoop. To achieve that range, interviewers are questioning every member of each household they visit.

    Going door to door.

    Chief survey designer Yu Xie queries a Gansu Province villager about his health and wealth.


    The survey's architects hope that the extensive interviews will help build a vivid portrait of Chinese society. And a design modeled after similar studies in the West means demographers and sociologists will be able to use the results to compare across cultures, says Hauser: “It will really improve the quality of data worldwide.”

    Chinese family values

    Not long ago, the Chinese government viewed most of the social sciences with suspicion. But by 2004, top leaders were bemoaning gaps in information as they sought to maintain social stability, sociologists say. With their university flush with research money, scholars from four Peking University departments convened to discuss the data dearth. They seized on the idea of a major panel survey and turned to Xie, who had experience with the University of Michigan's ongoing Panel Study of Income Dynamics, for help implementing it. What once might have been a prohibitively sensitive survey became a darling of China's most prestigious university.

    After securing local backing for a new research center—Peking University's Institute of Social Science Survey (ISSS) in Beijing—the Chinese scholars sought input from abroad. In addition to the Michigan survey, they looked at the British Household Panel Survey, the Taiwanese Panel Study of Family Dynamics, and the German Socio-Economic Panel Study, says ISSS director and survey co–principal investigator Qiu Zeqi. Xie and colleagues borrowed elements from all these efforts, then adapted questions and methodology to the rapidly developing country.

    China's effort has constraints. It steers clear of questions about the one-child policy, ethnicity, and politics. Minority regions like Tibet, Xinjiang, and Inner Mongolia are excluded, although Xie says this is mainly a logistical matter: Sending interviewers to query nomads on the Tibetan plateau, for instance, would be too costly.

    Although some hot-button issues remain off limits, the project does address subjects such as quality of life, social service needs, and the rich-poor gap. In addition to using specialized survey software, a 380-strong army of interviewers has been trained to “observe how wealthy the family is, how they interact, how clean the house is,” says Xie. The robust design allows researchers to analyze dynamics within families as well as make comparisons across neighborhoods, says demographer Robert Mare, president of the Population Association of America, who is not affiliated with the project. “Social scientists in the U.S. are very excited that this study will be carried out,” he says.

    In preparation for the project, the Chinese team in 2008 and 2009 conducted a pilot survey of more than 2300 households in Beijing, Shanghai, and Guangdong Province. Their findings, which are available upon request from ISSS, suggest that the economic reality in those major urban centers is a far cry from the picture frequently painted of China's boom.

    Marketing executives often rhapsodize about the appetite for luxury goods among urban Chinese. But the pilot survey showed that even in developed areas like Beijing, Shanghai, and Guangdong, überconsumers are a small percentage of the population. In 2009, an average of 80% of residents' expenditures went toward basics such as food, housing, and transportation. These burdens were unequally distributed, moreover: Rural people spent considerably more on health care than did city dwellers. (Both Beijing and Shanghai are administrative areas with both rural and urban populations.) Only 45% of respondents said they were satisfied with their lives, with more Beijingers describing themselves as happier on the whole than did residents of other areas.

    Expanding those inquiries nationwide will be far from easy. “One of the challenges is how to track people” for follow-up visits, says Qiu. Many rural Chinese lack home phones and change cell phone numbers frequently, and some 150 million to 180 million people migrate from the countryside to the cities for work. The solution, says Qiu, is to record contact information for three friends or relatives of each respondent. That safeguard proved invaluable during the pilot survey, when interviewers returning to study areas discovered that whole villages had been relocated to make way for construction projects. In the end, the team managed to track down about 80% of respondents.

    That success rate bodes well for the Family Panel Studies, which aim to gather data from a representative sample that would cover 95% of the population. True advances may be years down the line, when data allow for comparisons over time. But scholars are already excited. “This survey will show us societal development from individuals' perspectives,” says Ren Qiang, a sociologist at Peking University. That puts it far ahead of previous Chinese efforts, he says. “It's much, much better than what we had before.”

    • * Mara Hvistendahl is a writer based in Rotterdam, the Netherlands.

  2. Genomics

    Frog DNA Yields Clues to Vertebrate Genome Evolution

    1. Elizabeth Pennisi

    Add another group of animals to the growing menagerie of creatures whose genomes have been sequenced. On page 633 of this issue, Uffe Hellsten, a bioinformaticist at Lawrence Berkeley National Laboratory in California, and his colleagues describe the sequence of the Western clawed frog, Xenopus tropicalis, the first member of the amphibian branch of the tree of life to be so honored.

    Amphibians branched off from other vertebrates about 350 million years ago, and the group has been evolving along a path separate from mammals, reptiles, and birds ever since. “For this reason, the frog genome sequence provides unique insights into genome dynamics over an extended period of evolution,” says Ben Evans of McMaster University in Hamilton, Canada. “It fills in a crucial gap in our understanding of genome diversity and evolution of organisms,” adds David Cannatella, an evolutionary biologist at the University of Texas, Austin.

    Floating to fame.

    An aquatic frog, the Western clawed frog, now has a sequenced genome.


    The draft of the genome is in hundreds of pieces—not complete enough to be ordered chromosome by chromosome, but Hellsten and colleagues were able to match long stretches of contiguous sequence with equivalent sequences in the chicken and human genomes. A 150-million-base region in the center of human chromosome 1, for example, has a virtually identical counterpart in the frog and chicken genomes. “That implies that whole region has remained intact for 350 million years,” says Hellsten, and it represents an ancient chromosome. Other matchups indicated that three stretches of DNA fused onto human chromosome 1 after breaking off from elsewhere in the genome. Another intact region in chicken and frog split up in the human genome and spread across six chromosomes. “There appears to have been more frequent chromosome fusion and fission in mammals than in birds and frogs,” says Evans.

    The frog genome may offer new insights for not only evolutionary biologists but also biomedical scientists. It has 1700 genes that have been linked to human diseases such as type 2 diabetes, acute myeloid leukemia, alcoholism, sudden infant death syndrome, and congenital muscular dystrophy. These can be investigated using the frog to probe the basic mechanisms by which these genes work. “It opens a large number of doors for comparative and functional genomics,” says Erica Bree Rosenblum, an evolutionary biologist at the University of Idaho, Moscow.

    Researchers chose X. tropicalis to be the first amphibian sequenced because developmental biologists use it in their studies and it has a relatively small genome: 1.7 billion bases stretched across 10 chromosomes, about half the size of the human genome. Now, researchers are hungry for more. “One species of frog does not allow one to say very much about frogs,” says Cannatella. Others point out that Xenopus is unusual among frogs, so “now they need to do a typical frog,” says David Wake, an evolutionary biologist at the University of California, Berkeley. Cannatella would like to see the fire-bellied toad, Bombina orientalis, sequenced next.

    Nonetheless, says Stephen O'Brien, a geneticist at the National Cancer Institute branch in Frederick, Maryland, this Xenopus genome “is an important beginning and a treat for comparative genomics.”

  3. Marine Biology

    Deal to Legalize Whaling Would Sideline Science

    1. Virginia Morell

    The commercial killing of whales has been banned since 1986 by a body called the International Whaling Commission (IWC). At the time, commercial whaling had driven many whale populations nearly to extinction. But that ban was hobbled by several exceptions. Since then, a trio of whaling nations has killed more and more whales through the controversial loopholes, including research. “There isn't a real moratorium,” says Monica Medina, the head of the U.S. delegation to IWC. And IWC itself has been riven by internal tensions between those who want to save whales and those who aim to hunt them.

    Now, in a bid to tighten the organization's grip on its members' whaling and reduce the number of whales killed, IWC Chair Cristián Maquieira of Chile has proposed a controversial deal. In exchange for temporarily narrowing the loopholes, Japan, Norway, and Iceland would be allowed to commercially hunt whales for 10 years.

    The draft proposal—and the catch limits that Maquieira unveiled in Washington, D.C., last week—have inflamed conservationists. They fear that legalizing any form of commercial whaling will open the door to other nations and ultimately lead to more, not fewer, whale deaths. “This is a bad deal for whales,” says Patrick Ramage, global whale program manager for the International Fund for Animal Welfare in Yarmouth Port, Massachusetts. And several scientists on IWC's Scientific Committee charge that the proposed catch limits are not based on science—a stinging rebuke, since IWC's charter requires it to make its decisions using scientific findings.

    The proposal is designed to give IWC more authority over whaling by restricting the loopholes for a decade, in particular the controversial research exemption (Science, 27 April 2007, p. 532). It should also significantly reduce the number of whales being killed, says Maquieira. Nearly 1700 whales were harpooned last year, up from 300 in 1990. Using the research exemption, Japan killed about half of those 1700 whales, taking more than 500 Antarctic minke whales alone in the Southern Ocean Sanctuary. The plan would limit Japan's minke kills to 400 annually for the first 5 years, and then to 200. It would also increase Japan's fin whale quota in the sanctuary to 10. (Last year, Japan killed one.)

    Scientists say some of the proposed quotas were arrived at with little or no input from the scientific committee. In addition, the plan would permit Japan to commercially harpoon 120 common minkes annually in its coastal waters, from a population that many suspect is in trouble. Japan already kills more than 120 minkes there as by-catch, a term for accidental capture in fishing gear. “There's nothing in the proposal to limit the number of whales taken this way,” points out Scott Baker, a conservation geneticist at Oregon State University in Newport and a U.S. delegate to the scientific committee. That means the number of whales caught from this population is likely to go up.

    Other experts on IWC's Scientific Committee are not impressed, either. “The proposal is designed to look scientific,” says Justin Cooke, a mathematical modeler in Freiburg, Germany, who represents the International Union for Conservation of Nature. “But when you look at it carefully, you realize it doesn't provide any place for the input of scientific advice.”

    For instance, although the draft mentions the committee's procedure for determining sustainable catch levels, it's ambiguous whether those methods will be used, says Cooke. Instead, annual catch limits will apparently be negotiated, then remain fixed for 10 years. It's uncertain if the quotas would be revised during that period, even if new scientific data warrant a change.

    Slippery slope?

    Some experts fear a draft plan to eliminate research whaling will lead to more deaths, like those of this minke whale and her calf.


    Maquieira counters that several key parts of the agreement, such as compelling whaling vessels to carry tracking devices and independent observers, come from the recommendations of IWC's Scientific Committee. The tracking data and observers' reports would show that whalers are abiding by their quotas, he says. The proposal also calls for the whaling nations to carry out market surveys of whale meat and establish a DNA registry to make sure only certain species are hunted. But it's not clear who would do this. “If it's the whaling country itself, then it won't work,” Baker says. “It won't be the independent, transparent process it has to be to assure true compliance.”

    In another compromise, the proposal would create an enormous sanctuary for whales in the south Atlantic Ocean, running from the equator at Brazil to Tierra del Fuego and to West Africa, but would allow Japan to continue to hunt minke and fin whales in the existing Southern Ocean Sanctuary of Antarctica.

    Negotiations on these and other issues are expected to continue right up to IWC's full meeting in late June in Agadir, Morocco. The proposal must then win the approval of three-quarters of the members, and ratification is far from certain. Although Japan, Norway, and Iceland have not commented publicly, Australia's Environment Minister, Peter Garrett, has called the plan unacceptable, and New Zealand has called it inflammatory. The United States is “carefully reviewing” the proposal, Medina says.

    Already, conservation organizations are lobbying hard against the draft agreement and its catch limits. “They don't really reduce whaling but legitimize it,” says Ramage. Even though the agreement would prohibit other member nations from beginning whaling, South Korea, perhaps sensing an opening, has already submitted a request to do just that.

  4. Ethics

    DNA Returned to Tribe, Raising Questions About Consent

    1. Jennifer Couzin-Frankel

    A tiny tribe of Native Americans who live beneath the cliffs of the Grand Canyon is shaking up genetics research, thanks to an unusual out-of-court agreement with Arizona State University (ASU). Tribe members charged that their DNA had been collected by university researchers without proper consent; after a 6-year legal battle, the university has now agreed—among other concessions—to return more than 100 DNA samples to the Havasupai and pay $700,000.

    Although some tribe members had signed consent forms allowing blood samples collected 20 years ago to be studied broadly, they claimed in court that they had been told that the DNA would be used only for diabetes research. In fact, the data were used for a variety of studies. The outcome suggests that consent forms alone may not be enough to ensure that subjects understand how their samples may be used or to protect researchers.

    Six-year battle.

    Havasupai tribe member Rex Tilousi speaks after Arizona State University agreed to return DNA research samples and pay a cash settlement.


    The case may seem a footnote to popular medical studies that collect DNA and health information from thousands of people in the hunt for new disease genes. But to dismiss it as a story about Native American beliefs “would be unfortunate,” says Hank Greely, a law professor at Stanford University in Palo Alto, California, who has followed the case closely. “The same sort of thing can happen to any of us.”

    DNA samples matched with health histories are a precious resource, Greely says. Researchers are driven to use them as broadly as they can—whether to help ailing patients or to win tenure and grants. Pressure also comes from funding agencies, which demand that such data be shared, including through a database housed at the U.S. National Institutes of Health (NIH) called dbGaP. NIH requires that researchers it funds for genomewide association studies, which scan large stretches of the genome for disease DNA, deposit data in dbGaP. The agency is considering a similar requirement for all genomic data, says Laura Rodriguez, a genetics policy staffer at the National Human Genome Research Institute in Bethesda, Maryland, who helped design dbGaP.

    The Havasupai case is unique in some ways. Tribe members alleged that the samples were used for schizophrenia and ancestry studies that were deeply offensive to them. (The lead researcher, Therese Markow, now at the University of California, San Diego, denies that any schizophrenia work was conducted.) Lawsuits filed by the Havasupai, seeking more than $50 million in damages, claimed that researchers took tribe members' blood without informed consent. Markow strongly denies that charge; those who gave blood samples, she said in an interview, signed broad consent forms, and “a huge explanation was given about the kinds of research that might be done.”

    Nonetheless, an uproar ensued. The Havasupai case has led other Indian tribes to refuse to participate in research. It also illustrates that “consent is not a form, it's a process,” says Greely, who believes the tribe members didn't realize there might be any studies beyond diabetes, even years later. One alternative strategy for DNA research, described in a 2006 paper by a Canadian geneticist who works with aboriginal communities, is that individuals loan DNA for specific studies and retrieve their samples when the research is complete. “Research subjects need to have some ability to assert their property interests in their own biological samples,” says Kimberly TallBear, who studies the role of science and technology in Native American governance at the University of California, Berkeley.

    People who use dbGaP are well aware that they must be cautious about studies that go beyond the original intent for a particular set of genetic and health data. There are “multiple and specific checks of this exact issue, who's allowed to access the samples and for what purpose,” says David Altshuler of the Broad Institute in Cambridge, Massachusetts, who serves on a dbGaP working group. In some cases, data are restricted to certain types of studies, such as those pertaining to health but not ancestry. All dbGaP data—and most genetics information in other data banks worldwide—are stripped of identifiers.

    Most individuals who contribute their DNA, some studies have found, want science to benefit broadly and are not interested in being contacted for additional consent. But others may feel differently. Last year, a group from the state of Washington reported at the American Society of Human Genetics meeting that some volunteers had qualms about plans to put data from an Alzheimer's study in dbGaP. The local institutional review board had required that study leaders first ask subjects' permission, an unusual request. Of the 1340 surveyed, 88% consented, while 9.5% refused. The researchers were struck that even those who agreed were grateful to have been asked.

    Consent forms may talk in general terms about future use of data without explicitly mentioning dbGaP or other databases—in part because these data banks didn't exist when many forms were drawn up. The generic approach seemed sufficient in the past: “There was this perception that if we go back and ask [participants], and they all say yes, did we really need to bother?” says S. Malia Fullerton, a bioethicist at the University of Washington, Seattle, who participated in the Alzheimer's work. “That's been driving a lot of thinking in the policy arena.” But, she says, researchers may want to reconsider. Given that dbGaP now includes data from 188,000 individuals, if even a few percent don't want it there, “that's a lot of people,” says Greely.

    “Scientists had better be paying attention” to the Havasupai case, “and they better think how [their work] would look if publicized,” says Ellen Wright Clayton, who directs the Center for Biomedical Ethics and Society at Vanderbilt University in Nashville, Tennessee. Losing the trust of research participants would decimate genetics studies, she and others note—and such trust wouldn't be easy to regain.

  5. China

    Race to Contain Plague in Quake Zone

    1. Richard Stone
    Once bitten, twice shy.

    With care, researchers attempt to catch fleas at a marmot burrow in Qinghai.


    BEIJING—Disease specialists have launched an emergency operation in western China to avert a possible outbreak of pneumonic plague in the wake of a magnitude-6.9 earthquake in Qinghai Province.

    The 13 April quake, centered in Yushu County in southeastern Qinghai, killed 2220 people and left about 100,000 homeless. As relief crews race to shelter survivors and cremate victims, the Chinese Center for Disease Control and Prevention (CDC) this week dispatched to Qinghai a mobile biosafety level 3 (BSL-3) laboratory, capable of safely handling the most dangerous pathogens. The agency acquired the lab after the SARS epidemic in 2003; this is the first time it has been deployed. “We'll do whatever it takes to prevent an outbreak,” says Xu Jianguo, director of CDC's National Institute for Communicable Disease Control and Prevention (NICDC) in Beijing.

    Plague is endemic in 10 Chinese provinces; in Qinghai, it is spread by marmots, a burrowing rodent. In a typical year, western China reports a handful of plague cases, and most victims are marmot hunters. People bitten by fleas carrying Yersinia pestis can develop bubonic plague—the medieval Black Death—whereas those who inhale the bacterium can contract the pneumonic form. Both forms of the disease can be cured if antibiotics are given early, but pneumonic plague poses a greater threat because it spreads from person to person. The Yushu earthquake has created favorable conditions for pneumonic plague, says Nils Christian Stenseth, an ecologist at the University of Oslo who studies plague in China and Central Asia. He sees the potential for “a rather serious outbreak.”

    Like clockwork at about the end of April, marmots awaken from hibernation on the Qinghai-Tibetan Plateau. One scenario that Stenseth and others fear is that fleas will jump from infected marmots to rats and then to stray dogs and cats. An outbreak could spread quickly among survivors huddled in shelters.

    A few dozen researchers from NICDC and the Qinghai Institute for Endemic Diseases Prevention and Control in Xining, Qinghai's capital, have fanned out in the quake-affected area. It hasn't been easy for plague watchers: Last week, one NICDC scientist came down with altitude sickness and had to return to Beijing. In Yushu, the quake damaged a plague-monitoring station; its staff remain unaccounted for as Science went to press.

    Only about 40 plague cases have been reported in Yushu County in the past half-century, says NICDC senior plague specialist Yu Dongcheng. Of particular concern, he says, is the virulence of Qinghai's Y. pestis strain. “Inhaling even a single cell can cause disease,” asserts Yu. In comparison, he says, it typically requires a few hundred cells of strains in neighboring Yunnan Province to cause disease. Thanks to the mobile BSL-3 lab—one trailer with a positive-air-pressure lab chamber, and a second carrying the generator and water—“we'll be able to do experiments that we can't normally do in the field,” says Xu, such as isolating Y. pestis and running polymerase chain reaction tests.

    Prevention is a tall order. Marmot hunting has been banned, but pelts are valuable: Fur coats fetch more than $1000. Increasing the temptation, marmots ill with plague are easy to catch, says Yu. To limit marmot-human contact, researchers will cordon off plague-infested marmot burrows. It will be impossible to maintain a vigil on all marmots and animals they might come into contact with. “But if there are any human cases, we'll know,” Yu says. Only in September, when marmots hibernate for the winter, can researchers let down their guard.


    From Science's Online Daily News Site

    Chimps Grieve Over Dead Relatives New studies of chimpanzees conclude that our closest evolutionary cousins share many humanlike responses to death, including mourning. The work is some of the first evidence of grieving in animals other than humans, and it suggests that chimps may be more emotionally affected by death than many researchers realized.

    Dark Matter Halos Look a Bit Like a Football Dark matter is distributed throughout the universe in giant, football-shaped clumps, according to new, indirect images of the mysterious substance that holds galaxies and galaxy clusters together. The work provides more evidence that dark matter, even on the largest scale, strongly affects the visible cosmos with its gravity, although it remains remarkably unaffected in return.

    Elephants Have an Alarm Call for Bees East Africa's elephants face few threats in their savanna home, aside from humans and lions. But the behemoths are terrified of African bees, and with good reason. An angry swarm can sting elephants around their eyes and inside their trunks and pierce the skin of young calves. Now, a new study shows that the pachyderms utter a distinctive rumble in response to the sound of bees, the first time an alarm call has been identified in elephants.

    Did Monster Eruptions Warm the World? Talk about global warming. About 55 million years ago, the planet's temperature jumped by as much as 5°C and remained that way for about 170,000 years. Thousands of primitive marine species vanished. But the event also coincided with an unsurpassed era of plant diversity as well as the rise of mammals. Now, researchers think they've figured out what caused the hothouse: A series of massive undersea eruptions may have saturated the air with perhaps trillions of tons of methane—a much more potent greenhouse gas than carbon dioxide.

    Read the full postings, comments, and more at

  7. Scientific Freedom

    Iran Faculty Dismissals Seen as Result of New Policy

    1. Yudhijit Bhattacharjee

    Iran's government has begun to remove academics who oppose the authoritarian regime of President Mahmoud Ahmedinijad, according to human-rights activists in the country. Activists say that the dismissal this month of two electrical engineering professors at the Iran University of Science and Technology in Tehran is consistent with a recent edict by the Iranian science minister to fire faculty members who do not share “the regime's direction.”

    Science was unable to ascertain the official reason for the 13 April firings of S. Ali-Asghar Beheshti Shirazi, an expert in telecommunications, and his colleague, Alireza Mohammad Shahri, who, among other things, studies the detection of landmines. But human-rights activists say the pair were among 56 faculty members at the university who signed a 10 January letter to the chancellor decrying disciplinary actions taken against students who had participated in political protests on campus. The letter also expressed unhappiness over the beatings of protesters by outsiders, noting that universities needed to be maintained as “a place for political growth and social growth for students.”

    No tolerance.

    Kamran Daneshjoo, Iran's science minister, says academics who oppose the regime will be fired.


    Hadi Ghaemi, the New York City–based executive director of the International Campaign for Human Rights in Iran (ICHRI), says the 5 April ouster of Morteza Mardiha, a philosophy professor at Allameh Tabataba'i University, is another example of the government crackdown. Ghaemi points to a 4 March statement by Kamran Daneshjoo, Iran's minister of science, research, and technology, that faculty members who do not share “the regime's direction” and are not committed to the rule of the Supreme Leader would be fired. In addition to the firings, ICHRI claims that more than 50 prominent faculty members who are sympathetic to the reformist movement have been forced to retire over the past year.

    In parallel, the Iranian government appears to have opened the door to hiring and promoting faculty members who openly endorse the regime. Science has obtained a recent directive from the science ministry to universities describing procedures for evaluating existing faculty members and applicants. One form, titled “scientific qualifications,” lists academic criteria such as scientific publications and conference presentations. The other, titled “general qualifications,” ticks off some 17 criteria, including belief in the system of the Islamic Republic, being active in a local mosque, and cooperating with the institutions representing the Supreme Leader. The memo includes a form addressed to the intelligence ministry, asking for a report on the applicant's political and social background.

    This new evaluation process “opens up the system to political influence,” says Farhad Ardalan, a physicist who retired last year from Sharif University and is now a researcher at the Institute for Research in Fundamental Sciences in Tehran. “They have lowered the minimum so much that pretty much anybody could be hired,” he says. “It's the worst thing that has happened to Iranian universities in the past 30 years.” Adds Ghaemi, “These policies will cause severe damage to the quality and reputation of Iranian academic institutions.”

  8. Scientific Community

    Paul Nurse Chosen to Head Royal Society

    1. Jocelyn Kaiser

    Nobel Prize–winning biologist Paul Nurse is stepping down as president of Rockefeller University in New York City to become president of the Royal Society in London, the United Kingdom's science academy. Last week, the society's council nominated Nurse to succeed University of Cambridge astrophysicist Martin Rees, who ends his 5-year term in November. The society's 1327 fellows will vote in July.

    Home again.

    Nurse headed for London.


    The presidency of the 350-year-old Royal Society traditionally rotates between a biologist and a physical scientist. The council chose Nurse “with huge enthusiasm,” says member Matthew Freeman, a cell biologist at the Medical Research Council Laboratory of Molecular Biology in Cambridge, U.K.

    Nurse, 61, a British geneticist and cell biologist, shared the 2001 Nobel Prize in physiology or medicine with Leland Hartwell and Timothy Hunt for studies of cell cycle regulation. He came to Rockefeller in 2003 after serving as CEO of Cancer Research UK. Nurse will return to the United Kingdom at the end of this year but plans to maintain his 14-member yeast genetics and cell biology lab at Rockefeller. In a statement released by Rockefeller, Nurse said that his position as both leader and researcher at Rockefeller has been “ideal” and that “the decision to step down from the presidency is a very difficult one.”

    Nurse has an “astute political sense and ability to make a robust defense of the importance of fundamental research,” Freeman says. In addition to his scientific and administrative skills, he says, Nurse has also been “very involved” in engaging with the public on scientific issues. University of Oxford theoretical ecologist Robert May, who preceded Rees, calls Nurse “a standout choice.”

    Although Nurse's predecessors continued to do science, they worked in theoretical areas. Nurse's decision to keep his U.S. biology lab may pose a greater challenge, May says. But “a well-organized person can do both.”

  9. Space Physics

    Redesign Postpones Launch of Long-Delayed Space Station Experiment

    1. Adrian Cho

    Driven and independent, Samuel C. C. Ting has campaigned for 16 years to send a massive particle detector to the International Space Station. But just as researchers are preparing the $1.5 billion, 7.5-ton Alpha Magnetic Spectrometer (AMS) for liftoff on the last flight of NASA's space shuttle, Ting, a Nobel Prize–winning physicist at the Massachusetts Institute of Technology in Cambridge, has decided to swap out a key piece of hardware. That change will delay the launch, which was scheduled for 29 July, by months. But Ting says the change will prolong AMS's lifetime by many years, and those who know him say the move is likely not as rash as it appears.

    “I would never bet against Sam Ting,” says Nicholas Samios, a physicist at Brookhaven National Laboratory in Upton, New York. “He's very aggressive,” Samios says. But “he's a very careful guy, meticulous.”

    Proposed in 1994, AMS will search for antimatter lingering from the big bang, particles of dark matter, and other oddities by identifying every charged that passes through it. To distinguish electrons from positrons and iron nuclei from nickel, it measures how each particle's path bends in a magnetic field. The field was supposed to come from a 2350-kilogram superconducting coil that would generate a field about 17,000 times as strong as Earth's field. Now, Ting has decided to use a permanent magnet—akin to one on your refrigerator—that has a field one-fifth as strong and was used in a 1998 test run aboard the space shuttle. “The decision was fundamentally made by me,” Ting says.

    Part of the reason for the swap is because the superconducting coil generates more heat than expected. It must be chilled to nearly absolute zero with liquid helium, and the plan was to send along 2500 liters of liquid to keep AMS cold for 3 years. But recent tests at the European Space Agency's research and technology center in Noordwijk, Netherlands, suggest that AMS would boil off its helium in about 20 months, Ting says.


    NASA's space shuttle will deliver the Alpha Magnetic Spectrometer (octagonal apparatus) to the International Space Station, as in this drawing.


    However, a bigger reason for the change is that revised plans for the space station give AMS a chance to run even longer than 3 years, Ting says. NASA had planned to “deorbit” the space station in 2015, but in February officials announced plans to keep it aloft until at least 2020. AMS could keep running all those extra years but only if scientists switch to the permanent magnet, which needs no coolant. Otherwise, “after 3 years we'd have a museum piece up there,” Ting says.

    The switch to the weaker magnet will slightly diminish AMS's ability to measure a particle's mass and to study really heavy ones. Still, “AMS is 100 times better than any other particle detector that's ever been put into space,” says Jack Sandweiss, an AMS collaborator at Yale University.

    The flash retrofit will be a challenge, but Trent Martin, AMS project manager at NASA's Johnson Space Center in Houston, Texas, thinks researchers can pull it off. “I spent the last 3 weeks in Europe looking at whether this is possible, and I'm comfortable that they can make the change,” he says. No new launch date has been set.

    Replacing its magnet is hardly the first change of plans for AMS. NASA had scheduled a launch for 2003 but postponed it after the space shuttle Columbia disintegrated upon reentry that February. In 2005, the agency scratched AMS from its to-do list, but 3 years later Congress mandated its launch. Ting's commitment has never wavered, colleagues say. “He's a guy who pushes,” Samios says. “Any other mortal would have given up.” But in making a last-minute design change, Ting may be pushing his luck.

  10. ScienceInsider

    From the Science Policy Blog

    NASA Administrator Charles Bolden told a Senate spending panel that space science could suffer if the U.S. Congress forces NASA to stick with the Constellation program. The Administration wants to terminate that rocket effort under President Barack Obama's new space policy, which calls for a 2011 budget request that would boost NASA science to $5 billion, an 11% increase over current levels.

    A microbiologist who once worked with suspected anthrax mailer Bruce Ivins says his former colleague, who killed himself in 2008, wouldn't have had enough time to make all the spores contained in the 2001 letters. But another scientist who routinely makes anthrax stocks for research has disputed the testimony of Henry “Hank” Heine before a U.S. National Academies panel.

    A new report by the Institute of Medicine on Americans' salt intake suggests that the government gradually restrict the level of salt in food. It's also prompted speculation that the Food and Drug Administration plans to take action.

    The International Barcode of Life Project got a $35 million boost from Canadian agencies. The 26-nation effort collects specimens, sequences their DNA, and builds an informatics platform using digital bar codes to store and share information for species identification and discovery. The new funds, part available now and part spread over 5 years, bring the government's commitment to the world's largest biodiversity genomics project to $80 million and includes $2.2 million to enable researchers in five developing countries—Argentina, Costa Rica, Kenya, Peru, and South Africa—to play key roles.

    Mexico has established the Agencia Espacial Mexicana, its first space agency. It won't be sending astronauts into space or even building its own rockets but instead will develop space policy and stimulate aerospace investment.

    For the full postings and more, go to

  11. Cell Biology

    Beyond Clotting: The Powers of Platelets

    1. Mitch Leslie

    Platelets are known for thwarting blood loss, but new research shows these simplified cells defend against microbes and perform other duties—and they're also drug targets in sepsis and other conditions.

    Coming unstuck.

    Platelets like these enmeshed in a blood clot perform numerous jobs in the body.


    Thirty years ago, researchers were convinced that they had platelets pegged. Every milliliter of our blood, the thinking went, harbors hundreds of millions of these cell fragments for just one reason: to save us from bleeding to death. If we suffer a cut or other injury, platelets swarm into action, forming a plug that seals the wound.

    But in recent years, platelets have displayed powers no one imagined they had. They are healers that pour out growth factors and other soothing molecules that help damaged tissue rebuild. They are soldiers that spark the protective response known as inflammation, alert immune cells, and even attack microbial interlopers. They are long-haul truckers that pick up and deliver chemicals such as serotonin, which helps the liver regenerate after injury (Science, 7 April 2006, p. 104). They are even engineers, shaping the vascular system in newborns. “Platelets are certainly not just the Band-Aids of the bloodstream,” says hematologist Joseph Italiano of Harvard Medical School in Boston.

    Additional platelet functions continue to come to light, and biologists have just described a novel way that the body might make these multitalented cells—a finding that could one day ease the demand for donated blood. The new view of platelets as more complex and capable “has really got momentum now,” says hematologist Andrew Weyrich of the University of Utah in Salt Lake City.

    Yet for all their benefits, platelets will be the death of most of us, through blood clots that cause strokes and heart attacks. Platelets also foster cancer, rheumatoid arthritis, and other diseases.

    That means platelet-inhibiting medicines originally developed to stall blood clotting might have broader benefits, notes cardiologist Susan Smyth of the University of Kentucky in Lexington. Her lab, for instance, is investigating whether the anticlotting agent clopidogrel also helps against sepsis, an often-fatal condition in which bacterial infections run rampant in the bloodstream.

    Platelet factory

    It's easy to see why researchers underestimated platelets. Like the already simplified red blood cell, a platelet lacks a nucleus and all the myriad genes it normally contains. Yet platelets are even smaller—less than one-third the diameter of red blood cells—and some scientists maintain they don't even qualify as cells.

    But researchers have learned that platelets share many features and abilities with conventional cells—even, at least according to a controversial new study, the capacity to reproduce. Biologists have long thought that platelets, rather than forming through mitosis as most cells do, arise by breaking off from hulking bone marrow cells called megakaryocytes. Three years ago, scientists for the first time observed how this separation occurs in the bone marrow of living mice (Science, 21 September 2007, p. 1767). Tendrils from a megakaryocyte bore into a vessel, and the force of flowing blood pulls off pieces that further fission and eventually become platelets.

    But is that the only way platelets are born? The question is pressing because no lab has succeeded in growing clinical quantities of platelets—and they are desperately needed for medical traumas that involve lots of bleeding and for cancer patients whose platelet counts have plummeted because of chemotherapy. The supply for transfusions comes entirely from donated blood and can be stored for only about 5 days.

    In a paper published in January in the journal Blood, Weyrich and colleagues reported that they had caught platelets isolated from fresh blood in the act of reproducing. Instead of going through a conventional mitotic cell division, a platelet sends out a strand with one or more beadlike bulges. These progeny—which sometimes break off but often remain tethered to their parent—harbor standard platelet proteins and latch onto clotting proteins as they would at the site of a cut. Previous studies had noted such platelet necklaces in blood samples, but most researchers assumed they derived from megakaryocytes, not from platelets themselves.

    Weyrich says the findings show that platelets have the capacity for independent replication, though whether this process happens often enough naturally to lift a person's platelet count remains unclear. Italiano, whose lab is trying to cultivate platelets, concurs. “I think there's something here,” he says. “But the question is to what extent does it occur in the bloodstream.”

    Unexpected chemistry

    Platelets are chock-full of biologically influential molecules—not just ingredients for blood clotting but a wealth of growth factors, immune system messengers, enzymes, and other compounds. Researchers have identified more than 1100 kinds of proteins inside platelets or on their surface. The assumption had been that a platelet, given its lack of a nucleus, inherited these proteins from the megakaryocyte from which it had broken off.

    Yet platelets “are just as metabolically active as nucleated cells,” says immunologist John Semple of St. Michael's Hospital in Toronto, Canada. Indeed, platelets contain mitochondria, which provide cells with energy for chemical reactions and protein synthesis, and ribosomes, the structures cells use to make proteins from amino acids.

    Hints that platelets could build their own proteins began accumulating in the 1960s, when biologists discovered that the cells absorb free amino acids. And in 1988, researchers confirmed that platelets store small amounts of messenger RNA molecules (mRNAs). Yet some scientists objected that any protein production using these mRNAs was unimportant.

    In 1998, however, Weyrich and colleagues demonstrated that platelets fashion a particular protein, Bcl-3, in response to a specific stimulus, indicating that platelets carefully manage what they manufacture. Since then, Weyrich's group and other researchers have revealed that platelets make additional key proteins, such as the cytokine interleukin-1β, which induces inflammation, in response to chemical signals. Still, researchers need to pin down how much of its protein repertoire a platelet makes and how much it receives from its megakaryocyte mother.

    Cardiologist Jane Freedman of Boston University Medical Center cautions against giving platelets too much credit. “I think that platelets do a lot more than people think they do, but they don't have a nucleus” and thus can't perform all the functions of a conventional cell. Nonetheless, a clear picture is emerging, Weyrich says: “A platelet is dynamic and independent.”

    Attack of the killer platelets

    Their most visible profession is curbing blood loss, but platelets also “moonlight,” as Italiano puts it, at an assortment of jobs. In the January issue of Nature Medicine, for example, Steffen Massberg of the German Heart Centre Munich and colleagues reported a new developmental role for the cells. In mice, the researchers discovered, platelets ensure that the ductus arteriosus, a shunt that allows blood to bypass the lungs during fetal development, closes once the animals are born. Platelets form a clot in the ductus arteriosus and spur cells in the lining to form a permanent seal. The same mechanism seems to work in humans. The scientists retrospectively studied premature infants and found that those with low platelet counts were more likely to have a ductus arteriosus that remained open. If this connection is confirmed, it might lead to a new way to treat infants and premature babies, who are particularly susceptible to the condition.

    Parent and offspring?

    Platelet chains like these, in which the beadlike bulges contain standard platelet proteins, have convinced some researchers that the cells can reproduce.


    Platelets also appear to guard against microbial invasion. Six years ago, researchers discovered that, like pathogen-fighting macrophages and dendritic cells but unlike red blood cells, platelets sport Toll-like receptors (TLRs) that recognize molecular features of microbes. Semple and colleagues have found that when pathogens trip a platelet's TLRs, there's a surge in TNF-α, a compound that fuels inflammation, one of the body's most potent protections against infection.

    Sometimes platelets play a more active role in defense, latching onto invaders. They usually turn their captives over to macrophages that can destroy the microbes. But recent work suggests that they can do the job themselves: By hooking onto the surface of a red blood cell, they can kill malaria parasites lurking inside—though how isn't clear (Science, 6 February 2009, p. 797).

    Semple speculates that platelets are some of the most important pathogen detectors in the body. They are the second most numerous cells in the bloodstream, after red blood cells, and they circulate throughout the body and “pick up everything in the plasma,” he says.

    The immune talents of platelets are probably holdovers from an earlier era in animal evolution, when one cell type sufficed for microbial defense and hemostasis, or prevention of blood loss. Insects sport such multipurpose cells today, called hemocytes. “Platelets evolved to be hemostatic agents, but they kept their inflammatory functions,” says Semple.

    Gone septic

    Platelets may help newborns and ward off microbes, but they also cause plenty of misery. More than half the people who died in the United States last year were killed by platelets. Most fatalities resulted when a blood clot orchestrated by the cells lodged in an artery and caused a heart attack or stroke. That's why aspirin, clopidogrel, and other antiplatelet agents have found widespread use in people with atherosclerosis or several other conditions.

    Researchers have more recently found that another common killer owes a lot to platelets: sepsis, an inflammatory over-reaction to microbes in the blood that can devastate multiple organs. According to some estimates, sepsis kills more than 200,000 people in the United States every year.

    Developing drugs to combat sepsis has proved difficult, but two recent studies suggest that targeting the effects of platelets could offer a novel strategy. In 2007, immunologist Paul Kubes of the University of Calgary in Canada and colleagues reported that during a bloodstream infection, platelets that have detected bacteria via their TLRs glom onto neutrophils, a type of bacteria-slaying white blood cell. In response, the immune cells release neutrophil extracellular traps (NETs), webs of DNA that ensnare some kinds of microbes. In a small blood vessel in the lungs or liver, several neutrophils could be clinging to the lining, spinning a curtain of sticky strands that detain bacteria trying to pass through. This defensive mechanism “may be a last gasp if you have to get rid of a systemic infection,” says Kubes.

    Yet NETs can “cause collateral damage,” notes Kubes, by injuring the lining of blood vessels, which may harm the liver. When the team induced blood infections in rodents that lacked either platelets or neutrophils, the animals incurred less liver damage than did normal controls. Given this finding, Kubes speculates that drugs curbing platelet-triggered NET release could limit organ damage from sepsis.

    Platelets gone wild are also at the heart of a sepsis complication called disseminated intravascular coagulation. This condition, which is responsible for up to half of sepsis deaths, involves bleeding and widespread clotting within blood vessels. In a 2008 study in Nature Medicine, molecular biologist Jamey Marth of the University of California, Santa Barbara, and colleagues solved a molecular mystery and revealed how the liver tries to combat this dangerous coagulation by removing platelets from circulation.

    The researchers showed that some sepsis-causing bacteria release an enzyme called neuraminidase that prunes proteins on the surface of platelets. This modification might allow the bacteria to hook on and ride a platelet to a blood vessel injury, where they can infiltrate the surrounding tissue, Marth says. But the change also signals the body that a massive bacterial invasion is under way. And liver cells, using a protein called the Ashwell-Morell receptor, start grabbing and eliminating platelets sporting the altered proteins. The receptor is part of a last-ditch effort by the body to stop disseminated intravascular coagulation; no one had found a physiological function for this receptor despite 4 decades of study.

    Marth and colleagues are hoping that administering drugs that emulate bacterial neuraminidase in the early stages of sepsis could jump-start platelet removal before disseminated intravascular coagulation sets in. They are now investigating that possibility in animals.

    Platelet vs. joint

    Platelets' Jekyll-and-Hyde nature may also be evident in rheumatoid arthritis (RA), an autoimmune attack on the lining of joints. Researchers have usually attributed the painful and sometimes crippling symptoms of RA to the actions of immune cells such as T cells and B cells. But platelets' facility for triggering inflammation recently inspired rheumatologist David Lee of Harvard Medical School and colleagues to check for an RA connection. The researchers induced a form of RA in mice and then injected some of the animals with an antibody that destroyed 95% of their platelets. The platelet-deficient animals suffered milder joint inflammation than did the other rodents (Science, 29 January, p. 580).

    Done in by DNA.

    Bacteria (orange) caught in a mesh of DNA released by a neutrophil. Platelets that detect microbes can spur neutrophils to release these webs.


    However, when the researchers examined fluid from the joints of people with RA, platelets were scarce. Instead, the team detected myriad microparticles, sometimes termed platelet dust. These tiny capsules, discharged by stimulated platelets, brimmed with the inflammatory molecule IL-1.

    Lee and colleagues postulate a series of unfortunate events that begins when platelets passing through blood vessels of an already inflamed joint react to cartilage, releasing microparticles. In turn, the IL-1 in the particles prompts cells within the joint to emit molecules that promote further inflammation. Platelets don't instigate RA, they just worsen it, concludes Jerry Ware, a hematologist at the University of Arkansas for Medical Sciences in Little Rock who collaborated with Lee.

    The trigger for microparticle release is the receptor glycoprotein VI on the platelet surface, and the researchers speculate that blocking this receptor could deter platelets from unloading their inflammatory cargo. “This is a pathway that has not been previously targeted” in connection with RA, says Lee.

    Cancer's little helpers

    Cancer, too, seems to get an unfortunate boost from platelets. For example, they might aid tumors by promoting angiogenesis, the formation of new blood vessels. The late Judah Folkman of Harvard Medical School, who championed the importance of angiogenesis for tumor growth, pursued that possibility for a decade. Last year, in a paper that carried Folkman's name as a co-author, some of his former colleagues revealed that cancer cells change the chemical lineup of platelets.

    As part of its first-aid kit for injured tissue, a platelet carries molecules that spur or block angiogenesis, packaged into containers called granules. In mice with multiple tumors, platelet granules accumulated more angiogenesis-promoting molecules. “The tumor somehow subverts the platelet into making pro-angiogenic granules,” says Italiano, who was one of the study co-authors. The team now hopes to identify the cancer signals that influence platelets.

    Besides furnishing new blood vessels for a tumor, platelets might help maintain them, notes vascular biologist Denisa Wagner of Harvard Medical School. A tumor's blood supply is prone to leaks. That's because to immune cells “a tumor is kind of like a wound,” she says. They swarm into the newly forming blood vessels and trigger inflammation that can cause the walls to rupture. Four years ago, Wagner, Folkman, and colleagues reported that platelets prevented this vessel deterioration. And in 2008, Wagner and colleagues offered evidence that platelets must release some kind of protective molecule: Platelets that had discharged their chemical contents lost their vessel-saving powers. The identity of the molecular sealant remains a mystery, however.

    Cancers also recruit platelets to shield them from the immune system, according to research by tumor biologist Joseph Palumbo of the Cincinnati Children's Hospital Medical Center in Ohio and his colleague Jay Degen. Five years ago, they and their colleagues found that platelets protect tumors from attack by natural killer cells, one of the body's stalwart defenses against cancer. Although this protection wasn't necessary for the original growth to survive, it was essential for the tumor to spread, or metastasize. Palumbo suspects that platelets release a chemical or chemicals that disarm natural killer cells, but they remain unidentified.

    Researchers are just starting to try to turn their new knowledge about platelets into medical treatments. And Weyrich says we should expect yet more platelet functions to turn up: “I continue to be surprised by these guys.”

  12. Planetary Science

    Spunky Hayabusa Heads Home With Possible Payload

    1. Dennis Normile

    A record-setting Japanese mission to an asteroid is due to land in June after overcoming a 7-year history of mishaps.

    SAGAMIHARA, JAPAN—In a voyage fast becoming the stuff of spacefaring legend, Japan's Hayabusa asteroid mission, once thought lost, is coming home. Launched in 2003, the spacecraft has endured one mishap after another in the course of traveling more than 4 billion kilometers to retrieve samples from the asteroid Itokawa. “Spacecraft aren't supposed to survive such a string of difficulties,” says Erik Asphaug, a planetary scientist at the University of California, Santa Cruz.

    If nothing else goes wrong, Hayabusa will be the first spacecraft to return to Earth after landing and lifting off a celestial body other than the moon. Last week in Tokyo, the Japan Aerospace Exploration Agency (JAXA) announced that Hayabusa's sample-return capsule, which may or may not hold material from the asteroid, is expected to land near Woomera, Australia, on 13 June. The craft itself will burn up in the atmosphere.

    The mission has already achieved scientific stardom, however. The data transmitted back to Earth “changed the paradigm of how we think of small asteroids,” says Paul Abell, a planetary scientist at the Planetary Science Institute in Tucson, Arizona. If the return capsule contains particles from Itokawa, they will be the first fragments retrieved from a planetary body since Apollo astronauts hauled back their last load of moon rocks nearly 40 years ago. “It will be a huge bonus,” says Abell, who is a member of the Hayabusa science team assigned to NASA's Johnson Space Center in Houston, Texas.

    Hayabusa's success is all the more stunning considering what it has endured since the spacecraft was launched on 9 May 2003. By the time it reached Itokawa in September 2005, its solar panels had been degraded by a solar flare, malfunctions had shut down one of its four ion engines that generate thrust by expelling ions drawn from a plasma, and two of its three gyroscopelike reaction wheels, used to control attitude, had failed.

    Still, the mission soldiered on. To orient itself, Hayabusa relied on small thrusters originally intended to supplement the ion engines for rapid maneuvers. While the spacecraft maneuvered around the asteroid, a suite of instruments mapped Itokawa and determined its mineral and elemental composition, gravity, and density (Science, 2 June 2006, p. 1330).

    Prodigal son.

    Hayabusa is expected to return in June—bearing dust from asteroid Itokawa, researchers hope.


    Too far from Earth for real-time remote control, Hayabusa then autonomously navigated through a series of “practice” descents. During one, a microprobe intended to hop along the surface was lost after being released at the wrong altitude. Hayabusa then made two touchdowns, one lasting 30 minutes. Shortly after the second liftoff, ground controllers had problems commanding the craft. On 8 December 2005, they lost contact altogether. “Honestly, we thought it was the end of the project,” says Jun'ichiro Kawaguchi, Hayabusa project manager at JAXA's Institute of Space and Astronautical Science in Sagamihara, near Tokyo.

    Resuming operations hinged on whether the spacecraft's solar panels were facing the sun when it stopped tumbling. But the first challenge was communications. Normally, heaters would keep the oscillators in the spacecraft's transmitter and receiver at a predetermined temperature and, thus, a known frequency. But the heaters switched off, as other systems did, at the time of the accident. The team finally picked up a signal in January 2006, and Kawaguchi says the scientist on duty “did not believe it” at first.

    It took a couple of weeks to piece together a grim picture. Hayabusa's solar panels were just barely catching the sun's rays. Some of its batteries were shorted out. The hydrazine fuel used by the secondary propulsion system had bled off into space. The team surmised that a hydrazine “eruption” from a fuel line damaged during the second touchdown had knocked the craft into a tumble. Still, they concluded that they could point the ailing spacecraft on a route that would bring it to Earth by 2010, 3 years later than planned.

    Regaining control over Hayabusa “was much more difficult than we had anticipated,” Kawaguchi says. Finally, in April 2007, the spacecraft started its journey home. But troubles continued to pile up. A second ion engine failed, and a third lost its ability to generate the neutralizing electrons that must be emitted with the ions that provide thrust. The engine that idled early in the mission is now providing the necessary electrons. Setbacks aside, Kawaguchi says, the mission has shown that ion engines are effective for interplanetary travel and that autonomous navigation and control can land a spacecraft on distant bodies.

    Hayabusa's sample-collection technique was never tested. During each touchdown, Hayabusa was supposed to fire projectiles into Itokawa and gather any surface material that rebounded into a collection horn. But it seems that none were fired. On the first touchdown, the craft entered a safe mode that precluded sampling; it is not clear what happened on the second touchdown. The team hopes that dust stirred up during the two touchdowns settled in the collector. “But we won't be surprised if that canister is empty,” Kawaguchi says.

    Asphaug says the team still deserves a hero's welcome if the sample-return shell lands in the Woomera desert. Its success lays the groundwork for more complex missions, one of which could soon be on the drawing board. U.S. President Barrack Obama earlier this month set a goal of having astronauts land on an asteroid by 2025, and the scientists who eventually tackle that challenge will be able to go to school on Hayabusa's harrowing adventure.

  13. Society for American Archaeology Meeting

    Uncovering a Rural Chinese Pompeii

    1. Andrew Lawler

    Excavators are peeling back the layers of dirt on the village of Sanyangzhuang, which was buried by a flood on the Yellow River 2000 years ago, to reveal a unique 2000-year-old time capsule of Chinese rural life, they reported at the Society for American Archaeology meeting.

    Raising the roof.

    A sudden flood buried tiles set aside to repair a Han house.


    When the flood came, villagers fled in terror before a wall of silt-laden water from the Yellow River, leaving behind their fields, plows, pottery, and tile-roofed homes. But what was a disaster for the ancient people of Sanyangzhuang is a miracle for modern archaeologists. Up to 70 centimeters of silt buried the settlement completely, protecting it from the depredations of time. Now excavators are peeling back the layers of dirt to reveal a unique 2000-year-old time capsule of Chinese rural life.

    Although preserved texts record the official history of the Han dynasty at this time, Sanyangzhuang “offers us remarkable insight into daily life,” says archaeologist Tristram Kidder of Washington University in St. Louis, Missouri, who is working at the site under the direction of his Chinese colleague Haiwang Liu of the Henan Provincial Institute of Cultural Relics and Archaeology in Zhengzhou. “It's a superb and unprecedented archive.”

    The village, northwest of Shanghai in central China, was hit with a sheet flood, a sudden burst of muddy liquid carrying more than 200 kilograms of sediment per cubic meter of water. There was little warning; workers reroofing one compound left behind their tools and tiles. Although touted as an “Asian Pompeii” by the Chinese media, Sanyangzhuang was not the pleasure destination of a wealthy elite like the ancient Roman city. Buried about 10 or 11 B.C.E.—just a few decades before Pompeii—the village was a prosperous but hardworking farming center at the end of the Western Han period.

    Since Sanyangzhuang's initial discovery in 2003, archaeologists have begun to explore four large tile-roofed compounds with brick foundations, and they have found 10 more through coring 5 to 7 meters into the finegrained sediment. Each compound examined so far is surrounded by rich fields of wheat worked by villagers, as well as fired-brick–lined wells, toilets, ponds, cart tracks, and the remains of trees that once shaded the settlement. Although the inhabitants appear to have escaped, iron-tipped plows, hoof prints, and even the impressions of mulberry leaves—a sign of silk cultivation—were left behind. “This was a self-contained community as well as the start of the Silk Road,” Kidder told colleagues in a talk here. Much of the data is yet to be analyzed, but Kidder said that the biggest surprise is the prosperous nature of what was a backwater rural area.

    Henry Wright, an archaeologist at the University of Michigan, Ann Arbor, who has worked in China, said the digs promise to yield a detailed picture of China's hinterland at the height of the Han imperial state, which matched contemporary Rome in size and wealth. And he said that Kidder, who has dug in areas around the Mississippi River covered with similar silt, is providing Chinese archaeologists with new methods and tools for getting at the deeply buried material.

    Kidder suspects there may be other buried villages, towns, fields, and roads, because the flood affected not just Sanyangzhuang but a vast area over 1800 square kilometers. Remains of a Han-era wall 5 kilometers away could mark the site of a still-buried walled town. “This was a massive and catastrophic event,” he says, and it was noted in historical records of the time. Dikes in the area weren't repaired until 69 C.E., and the region did not recover until the 7th century C.E. Ironically, the disaster, like the violent end of Pompeii, may provide a wealth of information on the period. “A significant part of [this region] may be buried largely intact,” he says.

  14. Society for American Archaeology Meeting

    The Long Reach of the Monsoon

    1. Andrew Lawler

    New tree ring data detailing monsoon failures from 1250 C.E. to the present suggest that droughts coincided with political upheaval, presumably by causing crop failure, researchers reported at the Society for American Archaeology meeting.

    When the monsoons failed 6 centuries ago in Southeast Asia, they caused two terrible droughts that helped to bring down the Khmer civilization centered at Angkor Wat in today's Cambodia (Science, 20 February 2009, p. 999). Now researchers have evidence that later fluctuations in the monsoons can help explain dramatic social and political changes from India to China—and affect lives as far away as Mexico. New tree ring data detailing monsoon failures from 1250 C.E. to the present suggest that the droughts coincided with political upheaval, presumably by causing crop failure, says Brendan Buckley of Columbia University.

    In his talk, Buckley first outlined the Angkor-related results, also summarized in a recent paper in the Proceeding of the National Academy of Sciences. Using tree rings for dating and the size of the tree's annual growth ring as a proxy for rainfall, the team showed that 2-decade droughts starting in the 1340s and 1400s, with severe flooding in between, hit not just the area around Angkor but a wider region of Southeast Asia as well.

    Core issue.

    Columbia's Brendan Buckley gathers data from a Vietnamese tree.


    Such megadroughts were not confined to medieval times, says Buckley, who is a co-author of another paper published last week in Science (p. 486) that uses tree rings to lay out the pattern of monsoon failures during the last millennium. During the past 5 years, a group led by Columbia's Edward Cook scoured a wide swath of Asia for long-lived trees. They gathered 300 tree cores from the Himalayas, Siberia, China, Japan, and into Southeast Asia. Monsoon rains affect all these regions and so presumably affected the trees' growth.

    The team found many instances of monsoon failure that coincided with political upheaval. For example, a megadrought hit the region around Beijing prior to the demise of the Ming dynasty, a disaster which may have stoked the peasant revolt that upended the dynasty in 1644 C.E. Buckley said in his talk that the monsoon's long arm even extended to Mexico, affecting the El Niño cycle and contributing to a 16th century drought there; that drought coincided with Spanish-borne diseases and may have been a factor in the dramatic reduction in native populations.

    The team also pinpointed a megadrought that afflicted a wide area of southern Asia during the 1750s. This was a puzzling period when regimes from western India to Vietnam were roiled by revolts and wars that appear to have spread as far north as Siberia. Historian Victor Lieberman of the University of Michigan, Ann Arbor, has written extensively about the “strange parallels” of these 18th century upheavals. He welcomes what he calls “unprecedentedly reliable and detailed climatic data that have a strong bearing on political and economic reconstructions.” The new climatic data “force me to rethink entirely my understanding of the 17th and 18th centuries,” he says, by implicating climate as a potential common factor in the far-flung upheavals.

    Buckley says he is far from done with milking tree rings for clues to past climate. He hopes to find trees old enough to extend the Asian record back to 900 C.E.

  15. Society for American Archaeology Meeting

    Playing Politics Or Just a Game?

    1. Andrew Lawler

    At the Society for American Archaeology meeting, an archaeologist argued that the ball courts found throughout Mesoamerica likely began as a communal game and only later were co-opted by elites who used them for ritual and political goals.

    In ancient Mesoamerica, ball games weren't just for fun. The classic game, which involved a hard rubber ball and helmeted players on a rectangular field, had serious ritual and political goals—or at least that has been the conventional wisdom among archaeologists. But David Anderson of Tulane University in New Orleans, Louisiana, put a new twist on this story: He argued at the meeting that the ball courts found throughout Mesoamerica likely began as a communal game and only later were co-opted by elites who used them for their own ends.

    Ball courts were widespread in the Mayan Classic period from about 250 C.E. to 900 C.E. They have been found primarily at complex sites with large social differences, a sign that they were associated with elites. Iconographic evidence suggests that such games were used as tools for settling factional disputes, negotiating power relations, and redistributing food and wealth, as summarized in a classic 1996 paper by Harvard University anthropologist John Gerard Fox.

    Anderson analyzed a recent survey of northwest Yucatán by other archaeologists and found a different picture. The surveyors discovered nearly two dozen early ball courts from the Middle Preclassic period, which dates from 900 B.C.E. to 300 B.C.E. Only one was located at a place with obvious social distinctions—at Xtobo, once a thriving town that boasted nearly 400 structures, including pyramids and elite residences. But the other courts were all at modest villages. The smallest site, San Jeronimo I, consists of little more than the ball court itself. “Until recently, archaeology has focused primarily on the biggest sites, royal tombs, et cetera,” says Anderson. Because the ball game was pervasive at these sites, “we came to think of it as an elite game,” he says. “As we are now starting to look at the entire landscape, we are starting to find more and more signs of ball courts at smaller sites.”

    Play ball!

    The Chichen Itza ball court. The ritual Mayan game (inset) may have begun as a commoner's pastime.


    The data suggest that the ball game was brought to the Yucatán in the Early Preclassic, prior to about 900 B.C.E, “by the relatively egalitarian social groups of those times,” says Anderson. Ceramic figurines from the Middle Preclassic depict ball players, but iconographic depictions of ball games in stone, which are common later, are relatively rare in the early periods. This, combined with the location of ball courts in small settlements, requires archaeologists to rethink their early origin and use, says Anderson. “The ball game was a communal tradition known to all and accessible to most,” he says. “The earliest forms of the ball game in Mesoamerica represent a communal tradition of sport that was only later adopted by the sociopolitical elite to use for political ends.”

    Anderson's idea is intriguing, says Richard Diehl, a Mesoamerican anthropologist at the University of Alabama, Tuscaloosa. But he notes that there are hints that the game may have been played for ritual reasons, not just sport, even before Preclassic times. Rubber balls have been found in ritual caches dating back to 1400 B.C.E. at a Mexican site called El Manatí. This was during the time of the Olmec, the first in the region to develop a complex society. But evidence of ball courts in Olmec times remains questionable, Diehl and Anderson agree, and surprisingly few from any era have been excavated. To resolve Anderson's challenge, says Diehl, archaeologists need more digs.

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