News this Week

Science  20 Aug 2004:
Vol. 305, Issue 5687, pp. 1088

    Pediatric Study of ADHD Drug Draws High-Level Public Review

    1. Jennifer Couzin

    A trial that would give healthy children an amphetamine is prompting heated debate among pediatricians and bioethicists. A divided review board at the National Institutes of Health (NIH), which is sponsoring the study, has sent the proposal outside the agency for additional scrutiny. Early next month, a newly formed Food and Drug Administration (FDA) advisory panel will meet in an unprecedented public session to discuss the proposal's safety and ethics—the first such review of a trial that involves giving a drug to healthy children.

    The NIH study is designed to answer a long-standing question: Does a type of medication prescribed for hyperactivity affect the brains of children with attention deficit hyperactivity disorder (ADHD) differently than it does the brains of children without the condition? The scientist asking this question is Judith Rapoport, chief of child psychiatry at NIH's National Institute of Mental Health. Her project “could tell us a lot about what's dysfunctional in ADHD,” says F. Xavier Castellanos, director of research at the New York University Child Study Center in New York City.

    Still, “I can see why people are struggling” with the study, says Douglas Diekema, a pediatrician and bioethicist at Children's Hospital Regional Medical Center in Seattle, Washington, and chair of the institutional review board (IRB) that oversees clinical research at the hospital. On the one hand, he says, dextroamphetamine has been used for decades for ADHD and is generally considered safe. On the other, “you're actually giving [children] a psychoactive drug.”

    Rapoport and her colleagues aim to enroll 76 children, ages 9 to 18, including 24 sets of twins, only one of whom in each pair has the disorder. Subjects will receive a dose of dextroamphetamine and undergo functional magnetic resonance imaging scans. Participants will receive up to $570.

    This isn't the first time Rapoport has tried to understand how stimulants calm down children with ADHD. In 1980, she and her colleagues ran a trial at NIH that gave children with ADHD and normal children a dose of dextroamphetamine and examined their responses to cognitive and psychological tests. She found that the drugs had virtually identical effects on all subjects, such as enhancing concentration.

    Lighting up disparities.

    A controversial NIH study hopes to replicate much of this 1998 experiment, in which healthy and ADHD children received brain scans both while on Ritalin (right column) and off it (left column).

    CREDIT: C. J. VAIDYA ET AL., PNAS 95, 14494 (1998)

    Rapoport's findings prompted others to investigate. Chandan Vaidya and John Gabrieli of Stanford University added a layer of complexity in a 1998 study that gave a dose of Ritalin (an amphetamine-like drug) to 10 boys with ADHD and six controls. Brain scans showed differences in the drug's effects: In one area of the brain, the striatum, Ritalin boosted activity in ADHD children but suppressed it in healthy ones. That study sailed through the local review board with-out any problem, says Vaidya, now at Georgetown University in Washington, D.C.

    However, the world of human-subject research has changed since then. In 2000, the Department of Health and Human Services created the Office for Human Research Protections (OHRP) and shut down noncompliant studies at several prominent universities. The local IRBs that approve clinical projects became more cautious. Nearly two dozen flooded OHRP with inquiries about pediatric trials that the review boards worried exceeded “minimal risk” for children—an issue unique to pediatric studies. Before 2000, only two pediatric studies had received additional scrutiny from OHRP, according to Lainie Friedman Ross, a pediatrician and bioethicist at the University of Chicago. Since then, the office has ruled on six, approving three of them with modifications.

    The NIH board reviewing Rapoport's study arrived at a split verdict late last year. Ironically, many of the board's ethicists supported it, deeming one dose of the drug safe and nonaddictive; others familiar with dextroamphetamine compare this dose to a cup of coffee. “Research can't be risk-free,” says Ezekiel Emanuel, who heads the clinical bioethics division at NIH but isn't a member of the IRB that weighed this trial. Although declining to comment on the case, Emanuel notes that “IRBs confronted with unfamiliar things just think they're more risky than they are.”

    In three meetings between last October and January, the NIH review board narrowly decided that the study exceeded minimal risk for healthy children and, therefore, required OHRP's blessing. Several members were concerned that the proposed financial compensation might affect parental judgment. In addition, “one member felt giving a child a controlled substance (in the absence of a medical indication) could not be justified,” according to minutes from the IRB's November meeting. Indeed, many ethicists say privately that the use of an amphetamine—a drug that can be abused—raises more eyebrows than would a study involving a different, even riskier, medication, such as an antibiotic. Others say the study exceeds minimal risk simply because it calls for giving a prescription drug to healthy children.

    FDA is involved because prescription drugs fall under its purview. Now that the public has been invited in, it may stay. Julie Kaneshiro of OHRP's Division of Policy and Assurances says that the agency, after coming under pressure from outsiders, has decided to make public all future pediatric trial reviews.


    Citizens Sue to Block Montana Biodefense Lab

    1. Jocelyn Kaiser

    Montanans have gone to federal court in Missoula to block construction of a National Institutes of Health (NIH) biodefense laboratory in the city of Hamilton. The 12 August lawsuit, filed by the Coalition for a Safe Lab and two other groups, says NIH needs to improve safety plans before the lab is built.

    The new 600-square-meter facility, to be added to the National Institute of Allergy and Infectious Diseases' Rocky Mountain Laboratories, will be a biosafety level 4 (BSL-4), which means it could be used to study the deadliest pathogens, such as the Ebola virus (Science, 7 February 2003, p. 814). Officials have spent the past 2 years working with local groups on plans and drafting an environmental impact statement (EIS). NIH approved the project in June.

    Safety suit.

    Montana activists worry that proposed BSL-4 lab won't be safe enough.


    But opponents say the analysis lacks key elements, such as a plan for handling accidental releases. “The community would feel a whole lot better if there was a safety plan in place,” says coalition leader Mary Wulff. The groups also say that NIH didn't release key documents that would help them evaluate the EIS or discuss alternate locations and has not considered the possibility that the lab might study weapons-grade pathogens.

    Marshall Bloom, associate director of Rocky Mountain Labs, dismisses the concerns. The labs already have an emergency plan for the existing research space, he says, and can't fill in details for the new facility until it is built: “We don't even know the room numbers yet.” The suit asks the judge to require NIH to redo the EIS and halt groundbreaking, scheduled for September.


    Economist to Guide $22 Billion E.U. Science Programs

    1. Gretchen Vogel

    BERLIN—A Slovenian economist has been tapped to be Europe's next commissioner for science and research. Janez Potocnik, lead negotiator for Slovenia's entry into the European Union, is slated to take the reins of E.U. science policy, including the 5-year, $22 billion Framework 6 program that funds trans-European research.

    The appointment surprised many E.U. watchers, because the 46-year-old Potocnik has no background in the natural sciences. (Outgoing commissioner Philippe Busquin studied physics before entering Belgian politics.) However, Potocnik's political savvy and negotiating experience should be an advantage for European science, says Robert Blinc, a physicist at the Jozef Stefan Institute in Ljubljana: “He will certainly do more than … a Nobel Prize winner in this position. He can sell science.”

    E.U. commissioners are chosen more for their political experience than their field of expertise. Each of the 25 E.U. member countries appoints a commissioner to serve in the E.U.'s executive branch for 5-year terms, and the commission president then divvies up responsibilities for specific policy areas. On 12 August, the incoming commission president, José Manuel Barroso of Portugal, announced the portfolio he had assigned each of the newly nominated commission members. Once approved by the parliament, the new commission will take office on 1 November.


    Slovenian Janez Potocnik has been appointed the new E.U. commissioner for science and research.


    Potocnik is saying little to the press before the European Parliament's confirmation hearings, expected next month. But many E.U. scientists hope that he will back a European Research Council (ERC), a program to fund basic research proposals from individual scientists—a shift from the past emphasis on funding large multinational collaborations. A commission proposal in June (Science, 25 June, p. 1885) called for doubling the E.U. research budget to an annual average of $12 billion over the period from 2007 to 2013 and using part of the increase to start an ERC.

    Busquin, who in recent months has become a strong supporter of the idea, will leave some of the key negotiations with government ministers this fall to a temporary successor, incoming Belgian commissioner Louis Michel. Busquin was elected to the European Parliament this summer and will resign on 10 September to join the Parliament session that begins on 13 September.

    Educated at the University of Ljubljana, Potocnik has been Slovenia's minister for European affairs since 2002. From 1993 to 2001, he was director of the Institute of Macroeconomic Analysis and Development in Ljubljana. In 1998, he was appointed head of the team negotiating Slovenia's treaty to join the E.U. That experience should help him work the Brussels bureaucracy, say observers. “He knows the E.U. inside and out,” says economist Vladimir Gligorov of the Vienna Institute for International Economic Studies. He earned high marks, Gligorov says, for leading “what was largely thought to be the best negotiating team of all the new countries.”

    In light of that success, Potocnik is extremely well liked at home, Blinc says. “He has one of the highest approval rates of the former members of government,” according to Blinc. “If he became prime minister, we would be happy.” European scientists hope that his popularity will pay dividends for basic research.


    Reproductive Failure Threatens Bird Colonies on North Sea Coast

    1. Fiona Proffitt

    CAMBRIDGE, U.K.—Warden Deryk Shaw can't believe what he's not hearing as he patrols the cliffs of Fair Isle. The usual cacophony of 250,000 sea birds has been replaced by an eerie silence. That's because the kittiwakes, arctic terns, guillemots, razorbills, arctic skuas, and great skuas that usually breed on this southernmost Shetland Isle have failed to do their job this season. “It's the worst year ever here, by a long way,” says Shaw.

    As the sea-bird breeding season draws to a close on Britain's North Sea coast, scientists report that many colonies are failing to rear any young. The situation is “unprecedented in terms of its scale and the range of species it's affecting,” says ornithologist Eric Meek of the Royal Society for the Protection of Birds (RSPB) on the Orkney Islands. Many fear that rising sea temperatures and changing currents may be affecting the birds' food supplies, depressing reproduction.

    Although data on food supplies haven't yet been collated, anecdotal evidence suggests that the problem stems from a shortage of a key food source: sand eels, a small bottom-dwelling fish. Sea birds and humans alike appear to be having trouble finding them. The Danish fishing fleet, which catches 90% of the North Sea sand eel quota, caught only 36% of its 826,000-ton quota last year and has “undershot its quota quite substantially this year,” says Euan Dunn, head of marine policy at the RSPB. Sea-bird biologist Martin Heubeck of Aberdeen University adds, “Anything that's dependent on sand eels last year and this year is pretty well knackered.”

    The northern Shetland and Orkney sea-bird colonies, which are the most dependent on sand eels, are the worst affected; everywhere, surface feeders such as terns and kittiwakes have been hardest hit. More robust species such as common guillemots can dive deeper in pursuit of fish and were able to cope when sand eel stocks crashed in the late 1980s, says sea-bird biologist Robert Furness of the University of Glasgow, U.K. “Guillemots are not a species that normally shows year-to-year variation in breeding success,” explains sea-bird biologist Sarah Wanless of the Centre for Ecology and Hydrology (CEH) in Banchory, U.K. That they are now also succumbing is “causing everyone consternation,” she says.

    Hard hit.

    Surface-feeding kittiwakes have experienced a 30% decline in North Sea colonies since 1988.


    Experts say that the most likely causes for the decline in sand eels are past overfishing and rising sea temperatures. Previous research has linked rising temperatures to declines in the number of sand eels surviving to catchable size and to changes in their zooplankton prey. Sea temperatures have risen by about 1°C in the North Sea over the last 40-odd years, says marine ecologist Martin Edwards of the Sir Alistair Hardy Foundation for Ocean Sciences in Plymouth, U.K. And long-term plankton surveys indicate a “regime shift” in the North Sea in 1988, from a cold- to a warm-temperate ecosystem, explains Edwards. In particular, a cold-water species of copepod, a tiny crustacean that forms a key part of the North Sea food chain, has migrated 1000 km north, he says.

    Recent modeling by CEH scientists indicates that rising sea temperatures and sand eel harvesting strongly affect kittiwakes, whose North Sea populations have declined by about 30% since 1988. “In terms of the North Sea, we're talking about a system that had almost the severest fishing pressure of any sea in the world,” says Wanless. “Now it looks as if it's going to be subjected to severe pressure from climate change,” too.

    Furness, however, doubts that sea warming explains the pattern. He notes that the breeding crisis is worst in the northern North Sea, where sea temperatures are cooler. Instead, he suspects that adult herring, which have increased in numbers around Shetland, may be depleting the sand eel population. What's needed, he and others say, are studies linking oceanographic data with information on plankton, fisheries, and top marine predators such as sea birds.

    Interdisciplinary research is just beginning. “We've got all the bits of the jigsaw” in long-term data sets, says Wanless, but people need to begin to “put all of them together fairly rapidly.” The decline in kittiwake breeding populations, she fears, is “a sign that things have got into a serious state and may be very difficult to turn around.”


    Report Suggests NIH Weigh Consulting Ban

    1. Jocelyn Kaiser

    A new report from the federal Office of Government Ethics (OGE) hints that the National Institutes of Health (NIH) should consider a blanket ban on drug company consulting by intramural scientists. That suggestion runs counter to a proposal from NIH Director Elias Zerhouni that would concentrate on officials overseeing the extramural program and senior administrators.

    The 26 July OGE report, addressed to Department of Health and Human Services (HHS) ethics official Edgar Swindell, found many lapses at NIH (Science, 13 August, p. 929). Of 155 outside activities that OGE reviewed, 39 were approved after the start date, and 35 apparently weren't approved at all. The problems, OGE acting director Marilyn Glynn concludes, highlight the “difficulties inherent in a case-by-case approval method.”

    In recommending that NIH craft supplemental regulations for its employees, the OGE report notes that “the most compelling argument that can be made for any absolute prohibition on consulting with drug companies is that some NIH officials actually are involved in making clinical decisions affecting the health and safety of patients.” Even bench researchers studying drug products “could affect” the interests of companies, the report says.

    Some observers warn against banning all consulting by intramural scientists. “That would just be unfair,” says Paul Kincade, president of the Federation of American Societies for Experimental Biology. The report asks HHS to respond within 60 days.

    Ironically, in 1995, then-NIH Director Harold Varmus eased up on consulting restrictions after the OGE said NIH's practices needed to be codified or made consistent with laxer government-wide rules. An OGE review since then found relatively minor problems with NIH's consulting policies, leading one biomedical research advocate to characterize the new report as an exercise in “CYA”: covering your ass.


    Government Uses Carrot, Stick to Retain Graduate Students

    1. Yudhijit Bhattacharjee

    The Mexican government has cut back scholarships for graduate studies abroad while encouraging students to attend domestic programs. Officials say that the policy, which has been gathering steam over the past 5 years, is based not on the need to save money but on the ability of domestic institutions to offer graduate programs comparable to the best in the world. But critics say the move is depriving Mexican students of the best training in many fields and could hurt the country's scientific future.

    Since 2000, Mexico's National Council of Science and Technology (CONACYT) has slashed by more than half the number of international scholarships it grants every year, from 1469 to 691 this year. The number of domestic scholarships has risen from 4806 in 2001 to an expected 8100 this year.

    CONACYT officials argue that the quality of graduate-level scientific training has improved, making it less necessary for students to go overseas than was the case a generation ago. As evidence, Luis Gil, director of the CONACYT scholarship program, cites a jump in the number of “quality postgraduate programs,” from 431 in 2000 to 654 in 2002 (the most recent year for which figures are available). The list is compiled by CONACYT based on the judgments of scientists using factors that include numbers of faculty publications and foreign collaborations. In addition, say CONACYT officials, a rise in graduate enrollments in science and engineering—from 43,700 in 2000 to 47,300 in 2002—shows that domestic programs have become more attractive to Mexican students.


    Mexico has increased the total number of graduate scholarships while sending fewer students abroad.


    René Drucker Colín, a physiologist and coordinator of scientific research at the National Autonomous University of Mexico, agrees. “Overseas graduate training is a necessary option only in a few fields, such as space science, where Mexico can't afford the infrastructure,” he says. “Mexican universities can take care of everything else.”

    But although there is consensus between Mexico's scientific and academic communities that the country has made great strides in improving graduate education, many argue that not all fields are well represented. “We lack a critical mass of experts in many advanced disciplines such as genome sciences and nanotechnology,” says biotechnologist Octavio Paredes-López, president of the Mexican Academy of Sciences. “It's good to attract more students into domestic programs, but we also need to send more students for training overseas.”

    The new policy is penny-wise and pound-foolish, says Mario Molina, the Nobel Prize-winning atmospheric chemist who was born and raised in Mexico. Molina says the real problem is making the country more attractive for young scientists, regardless of where they were trained. “It would be a very good investment for Mexico to continue sending good students overseas,” says Molina, a professor at the Massachusetts Institute of Technology. “But it should be part of a larger strategy to build up scientific infrastructure so that these students can return to find satisfying career opportunities.”

    That's the problem facing José Álvarez-Chávez, a CONACYT fellow who recently finished his Ph.D. in fiber optics at the University of Southampton in the U.K. “I've applied for an academic job in Mexico, but all the institutions I've talked to say they don't have any positions available because of budget cuts,” he says. “And even if I did get a job at a university, I doubt that I'd have the resources to do experimental work.” Instead, Álvarez-Chávez plans to pursue a research career in Europe or in the United States.


    Cambodian Leader Throws Novel Prevention Trial Into Limbo

    1. Jon Cohen

    The status of a planned AIDS prevention trial among Cambodian sex workers is unclear after the country's leader ordered it halted. The trial, backed by the U.S. National Institute of Allergy and Infectious Diseases (NIAID) and the Bill and Melinda Gates Foundation (Science, 19 September 2003, p. 1660), was scheduled to begin this fall.

    The high-profile study, which would involve nearly 1000 sex workers in a novel use of the drug tenofovir, has been a target of community activists. On 12 August, Cambodian Ministry of Health officials notified U.S. and Australian collaborators that Prime Minister Hun Sen wanted the trial stopped. The researchers received scant information about the rationale for the decision. “It's really unclear,” says co-principal investigator Kimberly Page-Shafer of the University of California, San Francisco (UCSF). “I'm shocked.”

    The unusual study asks whether tenofovir, an antiretroviral drug on the market to treat HIV infection, can prevent the transmission of the virus. For the past 2 years, researchers from UCSF and the University of New South Wales (UNSW) in Sydney, Australia, have worked with Cambodian collaborators to design the placebo-controlled study in 960 sex workers who are at high risk of becoming infected. “Our research in Cambodia has always been conducted directly in collaboration with the government and clearly could only continue with government endorsement,” notes co-principal investigator John Kaldor of UNSW. The study already had received preliminary approval from a Cambodian ethics panel as well as one in the United States.

    Prevention intervention.

    Oxfam's Rosanna Barbero led opposition to the study.


    Concerns surfaced as early as June 2003, when Kaldor and collaborators from UCSF visited Cambodia to lay the groundwork for the study. Rosanna Barbero, who heads the Oxfam Hong Kong office in Phnom Penh and works closely with a large union of sex workers called the Women's Network for Unity, questioned why the researchers had come to Cambodia to do this trial in such a vulnerable group. “There's no culture of studies of any kind here,” said Barbero, who suggested that the trial was “probably not feasible here.”

    Last March, the Women's Network for Unity said they would participate only if volunteers would receive health insurance for 30 years, a period they argued would protect them against possible side effects. Tenofovir was chosen for the 1-year study because it has a better safety profile than any anti-HIV drug on the market. In a somewhat incongruous second protest, ACT UP Paris and the Asian Pacific Network of Sex Workers denounced the trial at the World AIDS Conference held last month in Bangkok, accusing the sponsors of “a blackmail system” because it offered participants access to better treatment and health care than they otherwise would have received. A jointly issued press release by these groups also took aim at Gilead, the California manufacturer of the drug, contending that the company “organizes the infection of sex workers.”

    UCSF's Page-Shafer stresses that the study has the support of several other groups of sex workers: “If Cambodian women participate, they're the first ones to benefit,” says Page-Shafer, who has worked on AIDS in Cambodia for several years.

    The study is one of a handful of trials now planned in Africa and the United States to assess whether regularly taking tenofovir can derail HIV transmission, a novel approach to prevention, which now focuses mainly on education campaigns, condoms, vaccines, and microbicides. The Gates Foundation funds several of the studies through a grant to Family Health International, which until June supported the Cambodian study. NIAID then took over as the main funder, committing $2.1 million for the first year.

    Mary Fanning, the NIAID medical officer in charge of the study, visited the trial headquarters in Phnom Penh in late July and said she had no inkling that Hun Sen had any reservations. In press accounts, Hun Sen suggested that the drug trials should be done in animals rather than in Cambodians. Tenofovir already has proven to be extremely effective as an HIV preventative in monkey experiments, and Fanning notes that it has passed the rigorous human studies required by the U.S. Food and Drug Administration.

    Hun Sen and his staff apparently left Cambodia soon after making his views known. The researchers are hoping to receive clarification soon.


    Druglike Molecules Mimic Gene Switches

    1. Robert F. Service

    It takes more than the right genes for good health. Those genes must also be switched on at the right times, a process known as transcription activation. When such activation goes awry, it can trigger diseases from cancer to diabetes.

    Proteins typically serve as the genetic on-off switches. Researchers have long sought to make small druglike molecules to carry out the same task. Now researchers at the University of Michigan, Ann Arbor, report that they have succeeded. “It's really exciting that they have small molecules that can mimic natural activators,” says Aseem Ansari, a biochemist at the University of Wisconsin, Madison.

    In the body, an activator protein typically does its job in two steps: One “arm” binds to its genetic targets, and another arm grabs onto other proteins that turn on the gene. Smaller biomolecules, such as RNA snippets and protein fragments called peptides, can also work as activators. But these compounds can break down quickly and have other drawbacks, Ansari says. Because the new small molecules are more durable, he adds, they eventually might serve as scaffolds for a new family of gene-controlling drugs.

    The research is described in the advance online publication of the Journal of the American Chemical Society. The Michigan team, led by chemist Anna Mapp, started by scrutinizing peptides known to activate particular genes. Although the peptides had different structures, they typically shared a handful of chemical features, such as phyenyl, hydroxyl, carboxylic acid, and isobutyl groups.

    Mapp and her graduate students Aaron Minter and Brian Brennan synthesized a family of ring-containing compounds, known as isoxazolidines, that harbor the same groups. Then they grafted on gene-seeking “arms” by fastening each molecule to a protein known to target the DNA in a well-known engineered gene. The researchers added an extract made from the nuclei of human cells to test tubes containing the modified isoxazolidine molecules and measured an uptick in messenger RNA from the target gene. That increase was a sign that the small molecules had switched on gene transcription.


    Life Without Numbers in the Amazon

    1. Constance Holden

    To what extent can concepts exist without the words to express them? That question has long occupied philosophers and linguists. Now, in an article published online this week by Science, Peter Gordon of Columbia University has added to the debate with an unusual study on mathematical thought. Among members of a tiny tribe in the Amazon jungle that has no words for numbers beyond two, the ability to conceptualize numbers is no better than it is among pigeons, chimps, or human infants, the psycholinguist finds. The research suggests that “without a language for numbers, people don't develop an ability to perceive exact numerosities,” he says.

    The Pirahã, a hunter-gatherer tribe of about 200 people, live in small villages on a tributary of the Amazon. They have little social structure and no art, and they barter instead of using currency. They also have one of the world's most phonemically limited languages, with just 10 consonants and vowels. Although the Pirahã have words for one and two (hói and hoí), even those only indicate approximations, says Gordon.

    A decade ago, Gordon visited the Pirahã to conduct fieldwork with linguist Daniel Everett, now at the University of Manchester, U.K., and his wife Keren, who spent 20 years with the tribe. Gordon gave a series of tests to the men (women and children were too shy to participate) to see how they dealt with concepts that have no representation in their language.

    Even in the simplest task— asking them to duplicate a row of up to 10 batteries he placed on a table—he found that the Pirahã performance started to decay after two or three batteries. They also did very poorly in a task requiring them to copy lines on a piece of paper (see picture). Tasks requiring cognitive manipulations of numbers were also beyond them. For example, the men could not retain the memory of a number, as demonstrated in a test where eight nuts were shown to them and then placed in a box.

    Tricky lineup.

    A Pirahã tribesman's number sense goes hazy after three.


    Perhaps the most striking result came from a test in which the men saw a piece of candy being put into a box with a picture of several fish on the lid. They were then shown the box with the candy in it and another box that had either one more or one fewer fish on its lid and asked to choose a box. Even though a correct guess meant a candy reward, subjects did no better than chance. Their performance “looks like what you see in infants or animals; the notion of a precise one-to-one correspondence is not there,” says Gordon.

    Although some linguists have hypothesized that humans possess an innate number sense, Gordon contends that his results cast doubt on this theory. “What's innate is being able to see [specific numbers] up to three,” says Gordon, who believes that this limitation is related to the fact that the Pirahã language is not recursive. For example, it is impossible for villagers to make comparisons such as “this pile of nuts is bigger than that pile.” Instead they would say one pile is big and the other is small.

    Calling the study “fantastic,” psychologist Lisa Feigenson of Johns Hopkins University in Baltimore, Maryland, says that language must be causing the “drastic” difference in the number sense of the Pirahã. Feigenson notes, however, that other cultures with limited number terminology have developed ways of expressing the concepts.

    Gordon says that the study favors a hypothesis by linguist Benjamin Lee Whorf, who believed that language is more a “mold” into which thought is cast than it is a reflection of thought. Everett takes a somewhat more interactive view, believing that the absence of both words and concepts for numbers is “the result of cultural constraints against quantification.”

    That view seems to be bolstered by the Everetts' attempts to teach the Pirahã numbers. Although children easily learned number words in Portuguese, the adults lost interest during the lessons. Everett also says years of attempts to teach adults to use the Brazilian currency came to naught, with adults telling him that “their ‘heads were too hard’” for this type of thing.


    Stormy Forecast for Climate Science

    1. Andrew Lawler

    With NASA's Earth Observing System complete, climate researchers are facing a confused and perilous future

    On 15 July, a spacecraft bristling with instruments to measure Earth's atmospheric chemistry soared into orbit. The successful launch of Aura rounds out NASA's Earth Observing System (EOS), an ambitious multibillion-dollar effort to understand global climate. The three large EOS platforms launched since 1999 join nearly a dozen smaller U.S. satellites monitoring everything from the world's ice sheets to solar radiation. The flotilla of instruments has left researchers awash in data. But they are learning that data alone won't buy happiness.

    Next week, as a group of senior scientists gathers on the coast of Massachusetts to debate the future of space-based earth science, the mood will be grim. Despite receiving nearly $2 billion in annual funding from the U.S. government, climate researchers say their discipline is in trouble. A fractious community has failed to come up with a clear scientific agenda, they say, and political support for climate change research is waning. The combination has created a deep crisis. “Earth scientists say they are fighting for their lives,” says Berrien Moore, a biogeochemical modeler at the University of New Hampshire in Durham, who will co-chair the National Research Council (NRC) meeting in Woods Hole, Massachusetts.

    The NRC meeting is an attempt to do for climate change what has been done for astronomy, planetary science, and solar physics: create consensus on a realistic, long-term blueprint for the field, including the most important questions to be answered and the tools needed to explore them. It won't be an easy task. Although NASA and the National Oceanic and Atmospheric Administration (NOAA) have requested the study, authority for climate research is spread among many federal agencies with different agendas. The topic draws researchers from innumerable subdisciplines—from geophysics to oceanography—and with vastly different needs. A white paper prepared by NRC staff and outside researchers for next week's gathering concludes that diffuse objectives and a lack of priorities have already left the program “marginalized and politically expendable.”

    “EOS has revolutionized earth sciences—but we can't fully appreciate it because we are inside the revolution.”

    —Berrien Moore, co-chair, NRC panel on space-based climate research


    Point of the spear

    That blunt assessment would probably have shocked the earth scientists who, a generation ago, conceived of EOS as a way to gather massive amounts of data for use in unlocking the mysteries of the complex global climate system. That vision became the centerpiece of a global change research program created by the U.S. government in 1990. The initial plan called for NASA to build and launch six massive platforms that, over 15 years, would gather simultaneous data on a host of ground, ocean, and atmosphere parameters.

    Then reality intervened. Staring at an estimated $30 billion price tag for building and operating the system, NASA delayed and scaled back its plans. The result is three smaller platforms—Terra, Aqua, and Aura—plus other more modest spacecraft. Even so, EOS accounted for half of the government's $1.6 billion climate change program by the time the first satellite, Terra, was launched in 1999 (see graphic, p. 1097).

    The size of a school bus, Terra's package of five instruments is examining land-surface changes, atmospheric aerosols, global cloud cover, and ocean temperatures. Aqua followed in 2002, with a half-dozen instruments measuring stratosphere temperatures and Earth's thermal radiation budget, among other parameters. Aura completed the trio of satellites in July with its focus on atmospheric chemistry. Each satellite is designed to run for 6 years, although each could last longer.

    The trio's scientific output has been staggering. From delivering 17 terabytes of data in 1999, EOS is expected to approach a delivery of 1000 terabytes this year. Despite those impressive data rates, the earth sciences community is bitterly divided over whether EOS has been worth the investment. Answering this question will be a difficult but important part of the NRC panel's job.

    Advocates argue that it is too early to judge the system's impact, given the years needed to first calibrate instruments and then sift through mountains of complex data. Moore contends that EOS “has revolutionized earth sciences—but we can't fully appreciate it because we are inside the revolution.” He expects that in a few years the data will help scientists produce much better climate models based on a better understanding of how the land surfaces, oceans, and atmosphere interact.

    And even if the science may be lagging, the EOS data system alone is a huge leap forward, says Lawrence Smarr, a computer scientist at the University of California, San Diego, and chair of the panel that advises NASA on earth sciences. It's the largest data system in use in the world, he says, and could pave the way for applications in many fields. “The EOS program has been at the point of the spear,” he adds. “They've been the pioneers.”

    Critics, however, say that the NASA satellite and data system has failed to deliver on its promise to be a coordinated system providing long-term coverage. “EOS is an unmitigated disaster,” says William Rossow, an atmospheric scientist at NASA's Goddard Institute for Space Studies in New York City. “I don't believe it has done much of anything.” He and others insist that EOS is actually an expensive and haphazard bevy of instruments with relatively short lives. They fear that the vast majority of EOS data, produced at such a high cost, is not being used—and will never prove useful.

    Few dispute, however, that satellites have given researchers a view of global systems that is far more sweeping than that obtained from in situ measurements taken on ocean buoys or balloons. But they have their foibles. Orbits decay and satellites drift. If an instrument measures temperatures in a region later in the day because of a change in orbit, for example, an apparent cooling trend may simply be a result of diurnal variation. As instruments become more sensitive, they also become more vulnerable to the harsh conditions of space. And calibrating instruments is still a painstaking process, which one scientist describes as “a black art.” Satellites also have their limits; they cannot provide detailed views of the ocean depths or what's happening under Antarctic ice sheets.

    Mount Vesuvius reigns over Italy's west coast in this view from a Terra instrument, one of five examining a wide range of earth, ocean, and air parameters.
    This glimpse of last fall's forest fires in southern California comes from one of six instruments monitoring clouds, atmosphere, humidity, and sea-surface temperatures.
    Scientists are still calibrating the five instruments that will probe Earth's atmosphere, including the Antarctic ozone hole.

    Many of NASA's smaller, cheaper, and more focused earth science satellites of the past decade have won plaudits from researchers. They include the 7-year-old Tropical Rainfall Measuring Mission, whose fate is up in the air (Science, 13 August, p. 927); a joint U.S.-French ocean observing satellite called TOPEX/Poseidon; and a mission to examine the elevation of Earth's ice sheets. NASA's earth science chief Ghassem Asrar notes that his agency has plans for 10 new missions—although none is on the scale of EOS.

    Just Say NOAA

    At the heart of the debate is how to satisfy researchers' needs for long-term, accurate, and continuous data streams. A related question is which federal agency should take the lead role for that next generation of climate research. Asrar argues that NASA is in the business of providing research satellites, not long-term operational spacecraft. He suggests that NOAA, which operates U.S. weather satellites, is in a better position to take charge of a post-EOS observation program. “The problem is that NASA wants to move on, but we say we need 20 to 30 more years of records,” says Mark Abbott, an oceanographer at Oregon State University in Corvallis.

    Scientists also fear that earth sciences at NASA are no longer seen as an up-and-coming enterprise. Asrar was just named deputy for a new science office that subsumes the old independent earth science office created in 1992. “A lot of earth scientists are afraid astronomy will eat their lunch when their lunch is already a quarter-sandwich short,” quips Charles Kennel, director of Scripps Institution of Oceanography in La Jolla, California, and chair of NASA's advisory council.

    Meanwhile, the agency's budget for earth science is projected to decline from today's $1.6 billion to $1.3 billion in 2008. And earth science's star seemed to pale further in January, when President George W. Bush told NASA to focus on astronaut missions to the moon and Mars. “If the Bush initiative goes somewhere, earth science will take it on the chin,” predicts John Townsend, former director of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

    NOAA Administrator Conrad C. Lautenbacher Jr. says his agency is ready and willing to take on the job of continuous climate monitoring. He sees that task as a natural extension of NOAA's long history of monitoring the weather, although he acknowledges that “I don't believe the process we have today is optimal.” But weather and climate science are not the same, say researchers, many of whom are skeptical of NOAA's ability to come up with the money and expertise to take over climate monitoring from NASA.

    NOAA's first big step into the field will be the National Polar-Orbiting Environmental Satellite System (NPOESS). A decade ago, NOAA and the Defense Department agreed to merge their two weather-monitoring systems, and the first of the $7 billion series is slated for launch by 2010, around the time EOS is winding down. Originally slated to be solely a weather satellite, NPOESS has added climate elements as well.


    Fields of sea ice melt in northeastern Canada's Hudson Bay


    U.S. coastal areas along the Gulf of Mexico


    A stretch of the Yangtze River in China, including the Wu Gorge


    Volcanoes along the Chilean-Argentinean border


    A great sea of linear dunes in Saudi Arabia


    In part to smooth the transition from EOS's research instruments to an operational system, NASA and NOAA plan to launch NPP—the NPOESS Preparatory Project—in 2006. The spacecraft will include four instruments derived from EOS. Greg Withey, who manages NOAA's satellites, says that “climate will get a nice ride” with NPP and NPOESS. And NASA's Asrar says the satellites will provide climate researchers with a continuity of data beyond EOS—as well as sufficient overlap to calibrate delicate climate instruments.

    But many researchers hotly dispute Asrar's assertion. “He is changing facts to fit his view,” complains Richard Goody, a Harvard University emeritus climate researcher. “Weather and climate systems are different.” Weather work typically requires high-resolution images without the absolute accuracy and stability that climate researchers say they need to do their jobs. Whereas a weather forecaster has little need to store data, climate researchers depend heavily on an organized and accurate long-term database. And weather and climate needs can conflict. For example, some EOS spacecraft are rolled in orbit so they can spot the moon and use it to calibrate delicate climate instruments. Although NASA is willing to take such risks, Withey admits that such a maneuver might be too dangerous for an operational satellite critical for national weather forecasting.

    Researchers are convinced that the needs of the weather program inevitably must trump those of climate. “There's a lot of angst about NPOESS,” says Bruce Wielicki of NASA's Langley Research Center in Hampton, Virginia. “It is not actually tasked to do climate.” And scientists' skepticism extends beyond NPOESS itself. They fear that NOAA—part of the U.S. Commerce Department—is ill equipped to handle the expensive and long-term task of climate observation. NOAA's $3.3 billion budget is less than one-fourth the size of NASA's, and it lacks a lab like the one at Goddard, which manages EOS, with the necessary talent and resources to handle a complex environmental research data and satellite system. “NOAA is the problem,” says Goody. “It has the mandate” on climate, he adds. “But it is not really a good research agency.”

    Wielicki also wonders who will pay for the extensive ground-based research, information systems, and infrastructure that NASA currently funds. “NOAA spends very little on these now,” he says. “I hope we can find a way to work with NASA and maybe the National Science Foundation.” Others suggest that NASA and NOAA should share Goddard's facilities to smooth the transition from NASA's research satellites to an operational system run by NOAA. Getting agencies to cooperate more closely, however, will be difficult, and researchers fear that their needs will fall through the government cracks.

    Cats and dogs

    But eliminating the confusion about agency roles won't resolve all the problems plaguing climate researchers. “I don't think the community has produced plans and programs which can be funded and supported,” says Lautenbacher. Adds Asrar: “There has been an absence of unified support in the [scientific] community.” Both men say they want earth scientists to come up with a clear list of future missions that federal agencies and Congress can support.

    “EOS is an unmitigated disaster. Idon't believe it has done much of anything.”

    —William Rossow, NASA Goddard Institute for Space Studies

    Part of the problem is that climate research remains a fragmented business. Rossow maintains that the vast majority of research is actually old-fashioned earth science in disguise. He says that scientists, instead of working on a problem such as how clouds interact with radiation, aerosols, and general planet circulation, too often simply extend previous work on cloud physics. “Our community blinds itself if it thinks it is doing climate,” he says. Goody agrees that the community jumped on climate research because that is where the money is and that it has failed to transform itself into an interdisciplinary powerhouse. Unlike an area such as systems biology, climate research remains too focused on small-scale issues, he and others say.

    Kevin Trenberth of the National Center for Atmospheric Research in Boulder, Colorado, recalls being “astonished and appalled” to learn that members of different Aqua instrument teams were not communicating with one another, although one of the reasons for launching several instruments on one platform was to compare simultaneous data. “We have a pile of numbers,” says Rossow. “But we need a structure to take these measurements and analyze them.”

    Wielicki says that taking the necessary interdisciplinary approach is tough work. To understand the global radiation budget, for example, his team is using 11 instruments on seven spacecraft. “It's a huge job,” he adds, despite the fact that they have data from an instrument that flew before EOS. “Other fields in most cases are doing this for the first time.” The diverse interests of earth scientists complicate the picture. “We're not like the astronomy community; our disciplines range from solid Earth to upper atmosphere to weather, climate, ecosystems, and oceanography,” says Richard Anthes, president of the University Corporation for Atmospheric Research in Boulder, Colorado, who is co-chairing the NRC panel with Moore. In the past few years, astronomers, solar system researchers, and solar physicists reached consensus on long-term plans and priorities for their respective fields. But reconciling the many and competing desires of climate researchers is a formidable task. Says Anthes: “The challenge is to hold this community of cats and dogs together.”

    Climate awakening

    Both NASA and NOAA want the NRC panel to review recent advances in Earth-system science, pose the principal scientific questions that need answers, and suggest which measurements and systems are needed. “We've got the foundation. We've got to figure out what kind of house we are going to build,” says Moore.

    Lion's share.

    NASA's EOS budget has consumed the largest single chunk of U.S. Global Change Research Program funds since the early 1990s.


    A central question is how to create and deploy a climate-observing system that can provide consistent and accurate data. Moore, Trenberth, Thomas R. Karl, director of the National Climatic Data Center in Asheville, North Carolina, and Carlos Nobre, director of Brazil's Center for Weather Forecasting and Climate Studies, recently proposed a climate observation and data system that would tie together all the world's environmental satellites, along with in situ data, a global telecommunications network, comprehensive models of the land, ocean, and atmosphere, and a center to monitor data quality.

    Karl says the space portion of such a system could instead use existing capabilities from many nations (see sidebar). Wielicki, however, estimates that a complete climate satellite system could cost $5 billion to $10 billion annually—more than triple what NASA now spends on Earth observation.

    Given the U.S. political climate, such an investment, even with contributions from other countries, seems highly unlikely. “What a waste of money! What would you do with the knowledge?” says one congressional aide. Whereas fiscal conservatives would attack any massive new research program as unaffordable, liberals are likely to see it as a ruse to delay action on the underlying problems that are causing global warming. Congressional “enthusiasm has waned,” adds the congressional aide. “It doesn't seem at all sexy or interesting.”

    A clear and comprehensive vision statement might help persuade skeptical politicians, says Withey. But Goody and others aren't convinced of the need for a bigger budget, especially with the trend toward microsatellites and miniature instruments. “The money in global change research is ample for what we need to do,” says Goody.

    Given these long- standing problems, climate researchers aren't sure how to regain the enthusiasm and high hopes of the early 1990s. Wielicki fears that it will take a disaster—“a really bizarre weather event such as a Category 6 storm or a falling ice sheet”—to alert the public and the politicians to the perils facing the planet. Without such a catastrophe, earth scientists will have to find another way to make their case that understanding climate change is every bit as important as finding life on Mars or warning citizens of an approaching hurricane.


    Stitching Together a Global System of Systems

    1. Andrew Lawler

    Keeping an eye on the planet is no simple task. NASA alone is currently flying 15 satellites designed to understand various aspects of the Earth system. Europe and Japan also have large spacecraft carrying out climate research, and there is a fleet of weather satellites operated by countries including India and China. And that's only what is in space: Many nations also deploy ocean buoys, balloons, and aircraft to gather additional climate and weather data on everything from atmospheric temperature to deep-ocean currents.

    Scientists have long dreamed of flowing together these many rivulets of data to create a common stream from which all climate researchers may drink. And last summer in Evian, France, leaders of the eight richest nations pledged to create a comprehensive, continuous, and coordinated system of global observation systems. Since then, 50 nations—from Argentina to Uzbekistan—have signed up to take part in what Charles Kennel, director of Scripps Institution of Oceanography in La Jolla, California, calls “a remarkable and profound event.”

    Slow going.

    NOAA's Conrad Lautenbacher is working on a coordinated plan for Earth observation.


    In February, ministers from around the world will gather in Belgium, the third such meeting since the one in Evian, to draw up a 10-year plan to coordinate observation plans, involve developing countries in data gathering, and exchange all data quickly and openly. But many researchers, frustrated by what they see as a lack of progress, fear that the entire exercise is part of an attempt by U.S. President George W. Bush to talk about climate change rather than take action. They also worry that further delays will produce a proliferation of redundant instruments and a chaotic sea of data. “How can this work when U.S. agencies aren't even able to coordinate?” asks Kevin Trenberth of the National Center for Atmospheric Research in Boulder, Colorado. Adds another climate researcher: “They've just created a new acronym and a new committee.”

    Such cynicism is unwarranted, says Conrad C. Lautenbacher Jr., chief of the National Oceanic and Atmospheric Administration (NOAA), which is the U.S. representative to the talks. The mere presence of so many high-level officials shows that governments are taking the issue seriously, argues NOAA's Greg Withey, who is in charge of satellite systems. “You don't get 40 to 50 ministers coming to a conference just because they like to travel,” he says. But Withey predicts “it is going to take another year” to come up with an approach that will iron out the technical difficulties of creating common data sets and calibrating instruments.

    Withey says that by the end of this year, NOAA will have a plan for U.S. observation strategy for the next decade to present at the February meeting. Japan is working on its own document, and Europe has just wrapped up work on a global system that combines environmental and security monitoring.


    New Dead Zone Off Oregon Coast Hints at Sea Change in Currents

    1. Robert F. Service

    Ocean scientists are scratching their heads about an apparently natural, seasonal onslaught of deadly water in the northeastern Pacific

    NEWPORT, OREGON—The data scroll in from an instrument cage being towed through the deep blue-green waters off the central Oregon coast. The meter-long cage, called an acrobat for its ability to “fly” below the water's surface, holds monitors that track the water's temperature, salinity, and levels of dissolved oxygen, chlorophyll, and organic matter. Anthony Kirincich, a physical oceanography graduate student at Oregon State University (OSU), Corvallis, toggles a black switch that tilts the cage's “wings,” pitching the acrobat toward the ocean bottom. Red, blue, and green lines on one of the laptop monitors aboard the research vessel Elakha start snaking.

    “We're diving, and you can see the dissolved oxygen is making a beeline toward the lower levels,” says Francis Chan, a marine ecology postdoctoral assistant at OSU. As the acrobat crosses the 50-meter mark, the green line representing dissolved oxygen sinks below the magic number of 1.43 milliliters of oxygen per liter of water, the minimum needed to support most marine life. The acrobat has just entered the “dead zone.”

    The zone is a several-kilometer-wide swath of nutrient-rich but oxygen-depleted water from the North Pacific that has recently welled up off the coast of Oregon. A similar dead zone first appeared for 2 months in the summer of 2002, suffocating vast numbers of crabs, rockfish, and other marine organisms that couldn't flee fast enough. Last year, oxygen-depleted “hypoxic” waters feigned another approach, but the winds that drive it onshore relaxed, causing it to slink off the coastal shelf. Now the dead zone is back, and Chan, Kirincich, and others think they may be witnessing the birth of a new seasonal ocean circulation phenomenon. But their excitement about doing new science is mixed with concern that the phenomenon may wreak havoc on Oregon's highly productive marine ecosystems.

    “It happened once, and [people thought] it was a fluke,” Chan says of the 2002 dead zone. “Now that we're seeing it again, it makes you at least curious and at worst alarmed at how fast these shifts can happen.” Adds Jane Lubchenco, a marine ecologist at OSU and one of the leaders of the team working to track the dead zone: “This coastal ecosystem off Oregon seems to be changing in a way we have never seen.”

    Pacific grim.

    Low-oxygen water creeping along the continental shelf killed bottom-dwelling crabs (left)—to the delight of scavenging starfish.


    Most dead zones are the result of human-induced pollution. Fertilizer and other nutrient-rich pollutants trigger blooms of phytoplankton, which suck oxygen out of the water when they decay. There are more than 30 such regions around the world. Naturally recurring dead zones fed by the upwelling of oxygen-poor waters, however, are known only off the coasts of Peru and South Africa, Lubchenco says.

    Lubchenco's team began tracking the emergence of this year's dead zone in June after coastal residents reported seeing dead crabs and fish washing up on beaches. Since then, the team has conducted shipboard monitoring surveys in a region that lay at the heart of the 2002 dead zone to gauge ocean conditions. By mid-July, the group had confirmed that a band of hypoxic water at least several kilometers wide had moved in off the coast. And in early August, their instruments reported the lowest dissolved oxygen levels of the season, 0.55 ml/liter at a depth of 90 meters. Videos of the ocean floor and the rare appearance of hundreds of dead crabs in an intertidal zone have added weight to the notion that a new dead zone has returned, although so far it's weaker than the one 2 years ago.

    The long-term effect of the dead zone hinges on whether it becomes a regular summertime fixture. Fish and crab populations seemed to recover quickly after the 2002 spell. But George Boehlert, who heads the Hatfield Marine Science Center in Newport, Rhode Island, says recurring hypoxic waters could harm juvenile fish, with serious but delayed impacts on adult populations. A persistent dead zone, says OSU physical oceanographer Jack Barth, could also mean that ocean circulation patterns in the Pacific may be changing. The nutrient-rich waters are part of a normal ocean current that carries water eastward across the North Pacific toward the North American coastline. That current splits near Vancouver Island, carrying some water northward along the coast of British Columbia and the rest south toward California. Temperature, salinity, and other measurements, Barth says, suggest that a change in wind conditions is forcing more of this North Pacific water southward, where some of it is lapping up onto the continental shelf off central Oregon. Once on the shelf, the cold hypoxic water is pulled up near the shore if winds blow surface waters away from the coast—as happened in 2002 and again this year.

    It's not clear what might be triggering the changing wind conditions and sea circulation patterns, Barth says. So far they don't appear to be linked to either El Niño or La Niña, which alter ocean and atmospheric circulation patterns across the Pacific. Another possibility is the Pacific Decadal Oscillation (PDO), a large-scale circulation change over as long as 4 decades. Evidence suggests that the PDO may have entered a new phase in 1998, but Barth says “we simply don't have enough evidence yet” to finger it as the cause of the new dead zone.

    Barth, Lubchenco, and others plan to keep a close eye on the waters here. “It's a bad thing that's happening,” Lubchenco says. “But it's so interesting that it's very exciting to watch.”


    Bees From the Rainforest Add Up to a $62,000 Coffee Buzz

    1. Jay Withgott*
    1. Jay Withgott writes from Portland, Oregon.

    PORTLAND, OREGON—A record number of ecologists—more than 4000—gathered here from 1 to 6 August for the 89th annual meeting of the Ecological Society of America (ESA). They discussed everything from ecosystem services to invasive species to fire ecology.

    In recent years, some economists and conservation biologists have tried to estimate the monetary value of natural eco- systems to people. In the best-known example, ecological economist Robert Costanza of the University of Maryland, College Park, and his colleagues calculated in 1997 that the planet's “ecosystem services”—air and water purification, nutrient cycling, waste decomposition, and more—are worth $33 trillion per year, an amount nearly twice the global gross domestic product. And in 2002, a team led by conservation scientist Andrew Balmford of the University of Cambridge, U.K., calculated that a worldwide network of nature reserves would be worth roughly $5 trillion, 100 times the value of exploiting the resources in them (Science, 9 August 2002, p. 950).

    Such global estimates, however, have little meaning to the farmer, rancher, industrialist, or city planner who makes land-use decisions based on considerations closer to home. So a team led by Taylor Ricketts of the World Wildlife Fund tackled a discrete local example. Their answer may help save patches of rainforest.

    Bee profitable.

    Pollination from nearby bees is worth $62,000 to a coffee farmer.


    The researchers homed in on a single coffee plantation in Costa Rica and measured the value of one ecosystem service, the pollination of the coffee crop by bees. Ricketts's team examined 11 bee species that visited coffee flowers from stands of rainforest that bordered the farm. Flowers near the forests received twice as many bee visits and twice as much pollen deposition as did flowers far from forests, they found. As a result, coffee plants near the forests had 20% greater yields and 27% fewer deformed beans. Combining these data with market prices for coffee, the team calculated that bee pollination accounts for $62,000, or 7%, of the farm's annual income. In addition, by providing multiple species of native bees, the forest patches served to stabilize pollination services year to year against the severe population fluctuations typical of feral honeybees.

    Just looking at the benefit from pollination, the value of preserving the natural forest stands is greater than the value of cutting down the forest for other uses, Ricketts told ESA attendees. For instance, cattle grazing would yield only $24,000 per year.

    The team's full cost-benefit analysis appears in the Proceedings of the National Academy of Sciences online on 11 August and in the upcoming issue of Conservation Biology. Ricketts and his colleagues plan to return to Costa Rica this winter to spread word of their findings among coffee farmers, government officials, and agricultural extension agents.

    The bee study “provides a tangible example of the benefits of [forests] in a way that's immediately relevant to the coffee farmers,” Balmford says. “The key to getting ecosystem services on the table for decision-making is to begin to quantify them in a locally relevant way.”


    Are Invasive Species Born Bad?

    1. Jay Withgott*
    1. Jay Withgott writes from Portland, Oregon.

    PORTLAND, OREGON—A record number of ecologists—more than 4000—gathered here from 1 to 6 August for the 89th annual meeting of the Ecological Society of America (ESA). They discussed everything from ecosystem services to invasive species to fire ecology.

    Honoring the bicentennial of Lewis and Clark's expedition through the newly acquired western territories, the official theme of this year's ESA meeting was the ecological exploration of inhabited landscapes. Based on the number of presentations, however, it might have been a conference devoted to invasive species.

    One key question for ecologists is what makes these interlopers so invasive. Do certain species simply have an innate potential to grow and reproduce rapidly? Or does invasiveness result from evolutionary changes that occur after an introduction? As ecologist Kristina Schierenbeck of California State University in Chico puts it, “Are invasive species ‘born’ or ‘made?’”

    Most ecologists have long assumed that invasiveness was just a matter of being in a favorable environment. If an organism introduced into a new region leaves behind its natural predators, competitors, and parasites, its chances of reproductive success increase. Recently, however, ecologists have explored whether species may also evolve to become invasive in their new homes. This “evolution of increased competitive ability” (EICA) hypothesis, proposed in 1995 by ecologists Bernd Blossey and Rolf Nötzold, is just now being tested rigorously.

    The meeting showcased “very compelling examples and evidence that EICA can occur,” says ecologist Dana Blumenthal of the U.S.D.A. Agricultural Research Service in Fort Collins, Colorado. But “the jury is still definitely out” on the extent of the phenomenon, he adds.

    The EICA hypothesis predicts that once an organism escapes its natural enemies, it no longer needs the defenses it had evolved against them. If these defenses use up precious energy or resources, natural selection should favor the organism investing instead in traits that give it a competitive edge over its new neighbors. For a plant, this could mean larger size, faster growth, or greater reproductive capacity, all adding to its invasive nature.

    Evidence for EICA was offered by Evan Siemann and William Rogers of Rice University in Houston, Texas, who work with the Chinese tallow tree, Sapium sebiferum. They have found that trees from introduced southern U.S. populations show faster growth and reduced investment in chemicals that defend against leaf-eating insects compared with trees from native Asian populations. As with most EICA studies, the work featured “common garden experiments,” in which native and introduced plants are grown side by side to control for environmental variables. The investigators found that Asian trees outperform American trees in settings with native Asian herbivorous insects, whereas American trees outperform Asian ones in settings without these insects. Many scientists, Blumenthal says, consider this evidence the strongest so far in support of the EICA hypothesis.

    Less is not more.

    Using fewer resources for defenses doesn't enable St. John's wort to grow faster in the United States.


    However, a study of the European plant garlic mustard, Alliaria petiolata, which arrived in North America 150 years ago, failed to support the hypothesis. Experiments presented by Oliver Bossdorf of the UFZ Centre for Environmental Research in Halle, Germany, and colleagues did show that American populations had lost their resistance to a European weevil that specializes on the plant. But when the group then grew American and European populations in side-by-side competition, plants from native European populations outgrew those from introduced American populations.

    Perhaps the most extensive common garden experiments thus far involve St. John's wort, Hypericum perforatum, the plant of alternative medicine fame, which was introduced from Europe to America 2 centuries ago. Ecologist John Maron of the University of Montana, Missoula, and his colleagues collected seeds from 50 St. John's wort populations across Europe and North America and then grew European and American plants in common gardens on both continents. Maron's group then measured levels of three chemicals the plants make to deter insects. The American plants exhibited lower levels of the chemicals, indicating they had lost defenses since their introduction. When grown in Europe, the American plants also suffered more infection and mortality than the natives, revealing that the apparently weakened defenses did have a real effect.

    Did the American plants that saved on defense invest their new gains into competitive ability, as the EICA hypothesis predicts? Apparently not. The American plants showed no trend toward larger size or greater reproductive ability when growing in the United States.

    Maron's work tested EICA more comprehensively than any previous study, according to some ecologists. “He did exactly the experiments that needed to be done,” says Marc Johnson of the University of Toronto.

    Maron doesn't perceive his results or those of Bossdorf's group as undermining EICA, however. He says that circumstances will vary for every species. Indeed, in Portland, both Blossey and Blumenthal summarized previous tests of the EICA hypothesis and found that of 14 studies, five supported EICA, one rejected it, and the remainder were inconclusive. “One flaw of EICA,” says ecologist Peter Kotanen of the University of Toronto, “is that it envisions a very simple tradeoff between defense and growth. The real world is more complicated.”

    Nonetheless, the ongoing rigorous assessment of the hypothesis demonstrates that the study of invasive species has come of age. “What I found striking at this meeting is how much invasion biology has matured,” says Kotanen. “We've gone from case histories and compilations to people finally doing experiments, and we've probably learned more in the last 10 years than in the 5 decades before.”


    Fighting Sudden Oak Death With Fire?

    1. Jay Withgott*
    1. Jay Withgott writes from Portland, Oregon.

    PORTLAND, OREGON—A record number of ecologists—more than 4000—gathered here from 1 to 6 August for the 89th annual meeting of the Ecological Society of America (ESA). They discussed everything from ecosystem services to invasive species to fire ecology.

    One of the most destructive invasive species these days is the water mold Phytophthora ramorum, the pathogen that causes sudden oak death (SOD). The suddenness with which it began ravaging trees in California's oak woodlands just a decade ago led researchers to suspect that it was introduced from elsewhere, although no one yet knows for sure.

    What is certain is that SOD threatens to drive several oak species into oblivion and profoundly alter the landscape of these woodlands. And the oak forests of eastern North America, where red oaks are known to be susceptible, could be next. The meeting, however, offered some possible good news for SOD researchers: Controlled fires might just provide a way to limit the spread of the troublesome pathogen.

    Fire rescue.

    Sudden oak death (on the leaves of a California bay plant) is less prevalent in areas that have burned (red on map).


    Fire ecologists Max Moritz of the University of California, Berkeley, and Dennis Odion of the University of California, Santa Barbara, collected data from state agencies on the pathogen's presence at different sites in California, as well as historical data on forest fires. They discovered that the disease was much less prevalent in areas that had burned since 1950. “You almost never see infections in [those] areas,” says Moritz. One reason, he and Odion speculate, could be that plant defenses against pathogens become weaker in older, unburned stands; trees need to invest more in competition with neighbors as stands age, and production of some defensive chemicals declines in older plants, for instance.

    Whatever the mechanism, the findings indicate that California's fight against forest fires over many decades may have precipitated or accelerated the SOD outbreak. However, the findings also suggest that controlled burning might help halt the disease. Moritz and Odion warn that careful experiments would be needed to determine whether prescribed burns have the desired effect.

    The rapid spread of SOD is “such a dynamic system that a lot of our tools in ecology for understanding and predicting patterns are inadequate,” says Richard Ostfeld of the Institute of Ecosystem Studies in Millbrook, New York. That's why the fire findings, he adds, are “both interesting and important” for battling the disease.

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