News this Week

Science  10 Mar 2006:
Vol. 311, Issue 5766, pp. 1356
  1. PROLIFERATION

    Last-Minute Nuclear Deal Has Long-Term Repercussions

    1. Richard Stone,
    2. Pallava Bagla*
    1. With reporting by Katherine Unger in Washington, D.C.

    NEW DELHI—The watershed agreement announced here last week by U.S. President George W. Bush and Indian Prime Minister Manmohan Singh rewrites the rules of the nuclear game. It would allow India to import nuclear technology and fuel to meet rising energy needs; in exchange, India—a nuclear weapons state that has long refused to sign the Nuclear Nonproliferation Treaty (NPT)—would open a majority of its nuclear power plants to international inspections. Although India has earned respect for keeping a lid on its nuclear secrets, the U.S. invitation to trade with the nuclear club is something new—and it will likely spur other nations to seek concessions.

    Atomic bonding.

    Bush and Singh have anchored their new “strategic partnership” on the nuclear pact.

    CREDIT: P. BAGLA/SCIENCE

    But the agreement is far from complete. In the coming weeks, Congress will scrutinize the fine print before deciding whether to make the changes in U.S. law needed to bring about a sea change in nonproliferation policy. The outlook is uncertain. Legislators praise the White House for strengthening ties with India, an emerging power and rival to China. But one big hurdle remains: The Bush Administration must convince Congress that the momentous agreement would make the world safer.

    Lost in the hullabaloo over nuclear power is another set of agreements signed last week that will result in a significant expansion of bilateral research cooperation. The new Science and Technology Commission with a $60 million war chest will fund projects in biotechnology and other areas. India has committed to taking two U.S. payloads, including a mineral mapper, on its first moon mission, scheduled for 2008. And a new $100 million, 3-year initiative will support agricultural research exchanges to nurture what Bush hopes will be a “second green revolution.”

    All the drama, however, centered on the nuclear accord, which Bush and Singh had agreed to in principle last July. Filling in the details proved difficult, especially on a provision that India segregate its nuclear program into two categories: civilian facilities open to international inspection and nuclear trade, and military installations off limits to both. Negotiations over the separation plan grew tense last December, when India put all R&D facilities, including its prototype fast breeder reactors, which run on plutonium, and CIRUS, a reactor in Mumbai presumed to have produced plutonium for weapons, on the military list (Science, 20 January, p. 318). In an interview with Science last month, Indian atomic chief Anil Kakodkar said that the U.S. desire to see the breeders brought under safeguards amounted to “changing the goalposts” and vowed that India would not open up more facilities to inspections (Science, 10 February, p. 765).

    Negotiations went down to the wire, with the sides talking through the night of Bush's arrival in New Delhi on 1 March. Morning light saw a deal in which India would put 14 of 22 planned or existing nuclear power reactors on the civilian list—leaving eight to use for military plutonium and tritium production, if it so desired. India has tagged all other facilities as military and retains the right to decide which future indigenous reactors to place under safeguards, although all reactors imported from now on would be subject to inspections. In the end, India made two key concessions: The “India-specific” safeguards, yet to be negotiated, would last in perpetuity—as long as countries do not withhold nuclear fuel. Singh told Parliament on 7 March that India would shut down CIRUS in 2010 and relocate Apsara, a light-water reactor, for safeguarding.

    Indian scientists praise the deal and their resolute negotiators. “It's a fantastic achievement,” says nuclear scientist V. S. Ramamurthy, secretary of the Department of Science and Technology. He adds that Kakodkar prevailed “against incredible odds.” Kakodkar too is pleased: “I am convinced this [agreement] is the practical way to move forward.”

    U.S. nonproliferation analysts, meanwhile, have their knives out. “The Bush Administration is sacrificing or selling out on what until this day have been some core U.S. nonproliferation values,” argues Daryl Kimball, executive director of the Arms Control Association, based in Washington, D.C. He and others say U.S. officials caved in. “We probably could have put more restraints on the fast breeder reactor program, but Bush stopped the negotiations,” says Stephen Cohen, a senior fellow of the Brookings Institution and member of the U.S. National Academies' Committee on International Security and Arms Control.

    Both sides agree that the deal places no constraints on India's nuclear weapons program. Even though India would sacrifice about a third of its warhead plutonium production if it closes CIRUS, it could erase that deficit by reprocessing plutonium in spent fuel from nonsafeguarded power reactors. This fuel currently contains about 9 metric tons of plutonium, says Kimball, enough for hundreds of bombs. But India could not convert it to weapons use easily: “They haven't got the capability to reprocess that much plutonium unless they build major new plants,” notes Matthew Bunn, a nonproliferation expert at Harvard University.

    There's another concern: India has scant domestic uranium resources, and lifting the ban on uranium sales “could indirectly assist India's military program” by freeing up more uranium, argues Kimball. Others doubt that India will seek to greatly expand its arsenal. The pact “should not be seen as a ploy to produce more and more fissile material for weapons. Getting access to cheaper uranium for energy production is the main driver,” says T. S. Gopi Rethinaraj, an arms-control expert at the National University of Singapore. Cohen worries that the deal could further devalue the NPT, which is already “severely damaged” by the defiant actions of Iran and North Korea.

    Drove a hard bargain.

    Indian scientists credit Anil Kakodkar with keeping breeder reactors off the table.

    CREDIT: P. BAGLA/SCIENCE

    U.S. legislators are waiting to see the details of the pact in a bill being drafted by the Administration. Before U.S. companies can dive into the Indian nuclear energy market, Congress must approve that bill and amend a 1978 nonproliferation law. Senator Joseph Biden of Delaware, a key Democrat on the panel that will vet the agreement, wants the Administration to show that the deal will not help India evade NPT restrictions or create a “double standard” that will encourage other countries to do so. Despite such misgivings, many analysts anticipate that Congress will give the pact a thumbs-up. “Shutting down CIRUS will help,” Rethinaraj says.

    Congressional approval would likely tumble a row of nuclear dominoes. For one, it would prompt the 45-nation Nuclear Suppliers Group to alter its rules, which for 30 years have prevented members from selling nuclear technology to India. It would also give a green light to India and France to implement a bilateral nuclear deal inked last month. Other nuclear suitors for Indian contracts would soon follow.

  2. SOLAR PHYSICS

    The Sun's Churning Innards Foretell More Solar Storms

    1. Richard A. Kerr

    Astronauts, power grid operators, and satellite managers had better watch out in 2012, a group of solar physicists warns. Drawing on their computer simulation of the circulation in the sun's interior, researchers at the National Center for Atmospheric Research (NCAR) predict that the next peak in sunspots will come a little late but will be far bigger than the last peak—bigger, in fact, than all but one of the 12 solar maxima since 1880. The accompanying solar storms could play havoc with satellite communications and threaten space station astronauts.

    The key to predicting solar activity years ahead, according to solar physicists Mausumi Dikpati, Peter Gilman, and Giuliana de Toma, is including data from enough past sunspot cycles. Every 11 years, the sun's dark spots and accompanying flares wax and wane. Predictions based on just the present strength of the magnetic field near the sun's poles—that is, the lingering remnants of the previous cycle's sunspots—call for an especially weak sunspot cycle coming up.

    Onward and upward.

    Solar physicists are predicting that the next peak in sunspots and other disruptive solar activity will exceed the previous solar max (squiggly line) because the previous three peaks contribute.

    CREDIT: NASA/MSFC/HATHAWAY

    But the NCAR group, located in Boulder, Colorado, thought that several past cycles might influence the coming one. When they ran their new model of the solar interior, they fed it with observations since 1880 to see how past cycles might assert their influence. They found that it takes a good 20 years for the magnetic remnants of past sunspots to recirculate deep into the interior, where the twisting action of the sun's rotation amplifies them, and to rise back to the surface near the equator as the next cycle's sunspots. The model did an impressively accurate job “hindcasting” the size and timing of past cycles. That track record made Dikpati confident that “the next solar cycle will be 30% to 50% stronger than the last solar cycle,” she told a media teleconference this week. The next cycle will begin 6 to 12 months later than average, in late 2007 or early 2008, according to the model, and will peak in 2012.

    The model-based prediction “is exciting stuff, the first new thing to come along” in decades, says Ernest Hildner, the recently retired director of the Space Environment Center in Boulder, the federal group charged with forecasting solar activity. It's especially exhilarating because “it finally answers the 150-year-old question: What causes the sunspot cycle?” solar astronomer David Hathaway of NASA's Marshall Space Flight Center in Huntsville, Alabama, told the teleconference. New work by Hathaway and colleagues supports the NCAR group's findings.

    If the sun is indeed gearing up for an especially active maximum, managers of everything from the Global Positioning System (which solar storms can disrupt) to low-orbiting satellites (which storms can drag down) could begin taking the threat into account. But as exciting as the forecast is, promising techniques for predicting the future have failed before, Hildner points out: “You still have to wait and see.”

  3. SPACE SCIENCE

    NASA Agrees to Review What's on the Chopping Block

    1. Andrew Lawler

    NASA's science chief has offered space and earth scientists half a loaf in response to withering complaints about cuts in the agency's proposed 2007 budget. Even so, it's a better offer than the one NASA Administrator Michael Griffin made last week to life and microgravity scientists: He announced a new timetable for finishing the international space station that will leave almost no room in the next 4 years for U.S. research projects.

    Goliath tops David.

    Work continues on the James Webb Space Telescope, while NASA recently canceled the smaller NuSTAR mission (inset).

    CREDIT: NORTHRUP GRUMMAN; (INSET) GSFC/NASA

    Testifying before the House Science Committee, NASA's Mary Cleave pledged to rethink the space agency's proposed cuts after legislators and researchers complained about their impact on young researchers and smaller missions. (One of those missions, to two asteroids, was canceled the same day.) Cleave said there was a catch, however: Shifting money back into those areas could spell doom for flagship spacecraft now under development for astronomers, earth scientists, and solar physicists. But senior researchers at the hearing said they would be willing to consider such a tradeoff.

    That same afternoon, Griffin announced that NASA will not pursue most of the planned research activity on the space station before the orbiting base is complete in 2010. The change results from a cost-and timesaving reduction in the number of space shuttle flights needed to boost the hardware into space—missions that would have allowed astronauts to carry out a host of experiments. Speaking at a press conference at Kennedy Space Center in Florida with the leaders of other space agencies, Griffin declined to discuss the U.S. research agenda after 2010, but it appears bleak. Russian Federal Space Agency chief Anatoly Perminov says NASA will provide the Russian section of the station with additional electrical power.

    NASA's cancellation of the Dawn mission, awaiting a June launch to the Vesta and Ceres asteroids, drew a swift response from scientists. “I was shocked that after testifying before your committee yesterday, the first thing Dr. Mary Cleave did upon returning to her office was to cancel the Dawn Discovery mission,” wrote Mark Sykes, director of the Planetary Science Institute in Tucson, Arizona, to committee chair Representative Sherwood Boehlert (R-NY). Although Sykes maintains that critical technical issues have been resolved, Cleave told Science that a recent review found expected cost overruns exceeding 20% and the project facing more than a 1-year delay. Her office was in the process of notifying scientists before the hearing, she noted, but legislators did not ask her about the mission.

    At the hearing, both Republican and Democratic legislators expressed outrage at cuts, proposed last month in NASA's 2007 budget, to a host of robotic science missions as well as to biology on the space station. A panel of scientists also lambasted NASA for proposing to reduce research grants, typically 3-year awards of less than $100,000, and small missions. The cuts “would be disproportionately felt by the younger members of the community,” warned Joseph Taylor, a physicist at Princeton University. “Without research support to pay for their time, this group will be forced to turn to other fields—or leave the sciences altogether.”

    Pressed by Boehlert to offer an alternative, Taylor pointed to the servicing mission for the Hubble Space Telescope and to the James Webb Space Telescope. The Webb telescope remains $1 billion over budget, despite recent attempts to cut back its costs, and the Hubble mission is the second largest effort within NASA's astronomy plan. Taylor said he would consider sacrificing one of those to rescue grants and small missions. Astrophysicist Fran Bagenal of the University of Colorado, Boulder, added that restoring money to those two areas would “justify a delay in flagships” such as the Solar Dynamics Observatory, to be launched in 2008 to examine solar variability.

    Some flagship missions already have been delayed or canceled. A 2010 launch for NASA's $850 million Global Precipitation Measurement mission has been stretched to 2013, and NASA has twice canceled plans for a major spacecraft to study Jupiter's moon Europa. “This marks the first time in 4 decades when we have no solar system flagship at all,” noted Wes Huntress, a geophysicist at the Carnegie Institution of Washington and a former NASA space science chief.

    That somber situation might look good to life and microgravity scientists, who would be largely shut out over the next 4 years of space station construction and perhaps longer. Before the Columbia disaster, NASA planned 28 shuttle flights, many carrying scientific equipment to and from the facility. Now the number stands at 16. “It is the same space station,” Griffin said. “But we are largely deferring utilization.”

    In good news for the station's partners, NASA agreed to launch the European and Japanese scientific modules earlier than planned so that non-U.S.-based research could begin in 2008. In exchange for not launching a Russian power module, NASA also will funnel power to the Russian portion of the station. A portion of that power was once designated for experiments aboard the U.S. lab module.

  4. ARCHAEOLOGY

    Dates Revise Easter Island History

    1. Ann Gibbons

    When Dutch explorers landed on a remote Pacific island a few days after Easter Day 1722, they found eerie carvings of huge stone statues, a barren landscape, and natives with dwindling supplies of food and wood. Ever since, Easter Island, now known as Rapa Nui, has been considered a textbook example of a once-thriving culture that doomed itself by destroying its own fragile habitat.

    Monumental price.

    The building of immense statues helped deforest Easter Island.

    CREDIT: TERRY HUNT

    Now a paper appearing online in Science this week (www.sciencemag.org/cgi/content/abstract/1121879) revises that story, implying that construction of the statues and degradation of the environment both began almost immediately after humans set foot on the island. New radiocarbon dates and a reanalysis of old ones put humans first on Rapa Nui at about 1200 C.E., 400 to 800 years later than previously estimated and just 100 years before the palm trees begin to vanish. “You don't have this Garden of Eden period for 400 to 800 years,” says lead author Terry Hunt of the University of Hawaii, Manoa. “Instead, they have an immediate impact. The destruction-of-the-environment story is on steroids.”

    Other researchers, such as archaeologist Patrick Kirch of the University of California, Berkeley, agree that the new dates raise serious questions about whether the Easter Island residents ever lived sustainably on the island. But some question the team's dismissal of some older radiocarbon dates. “I'm not convinced they made the case for a later occupation,” says Kirch.

    By the time the Dutch landed, the Easter Islanders—and the Polynesian rats that had stowed away in their canoes—had destroyed most of the subtropical trees and giant palms that provided wood for canoes and for transporting statues, as well as fuel for fire. The settlers also had wiped out many species of birds. But most researchers thought that there was a period during which the islanders had lived in harmony with the environment, before they taxed their resources with a complex culture and statue building. Earlier radiocarbon dates seemed to support that idea, suggesting colonization between 800 C.E. and 1200 C.E. and ecological collapse, as indicated by the disappearance of palm trees, starting at least 400 years later.

    Hunt and co-author Carl Lipo of California State University, Long Beach, took eight samples of wood charcoal from the bottom of the oldest known archaeological site on the island, called Anakena. When they got radiocarbon dates that clustered at about 1200 C.E., Hunt at first assumed the dates were wrong and put them aside. But later he and Lipo decided to scrutinize all earlier dates from Anakena, to make sure they did not contain carbon from marine organisms or old wood, which can skew dates too old. After discarding what they considered unreliable dates, the pair found a high probability (50%) for the first human settlement starting just after 1200 C.E. The evidence does not rule out an occupation at 1000 C.E., but the probability is very low, says Hunt. The new dates are a “significant improvement” over the old ones, says radiocarbon-dating expert Tim Higham of Oxford University, U.K.

    Although several researchers welcome the rigorous analysis of dates, not everyone agrees with the criteria the team used. “Some of his criteria are fair; others are not,” says zoologist David Steadman of the Florida Museum of Natural History in Gainesville, whose 1000 C.E. dates for Anakena were left in the pair's analysis.

    The new results are in keeping with a trend in the past decade toward later dates for colonization of some of the outermost Pacific islands. “This is an important paper, because it is part of a revision on the chronology of the Pacific that shows there is a big gap between settling west Polynesia [e.g., Samoa] and the marginal areas of south and east Polynesia,” such as New Zealand, says archaeologist Atholl Anderson of the Australian National University in Canberra.

    The new dates won't be the final word on the first colonization of Easter Island, researchers say. “The chances you're going to find the first campfire are pretty slim,” says Steadman. “It will enliven the debate and force everybody to take a critical look at their dates.”

  5. SOLID STATE PHYSICS

    Theory of Shock Waves Clears Up the Puzzling Graininess of Crystals

    1. Adrian Cho

    Ideally, a crystalline material ought to be a realm of perfect atomic order. Real-world crystals, however, consist of small grains and cells that lock together higgledy-piggledy, like so many stones in a wall. For decades, physicists have struggled to explain where the boundaries delineating grains and cells come from. Now theorists have shown how these walls form out of stringy imperfections in the crystal called dislocations.

    The advance could lead to a deeper understanding of the grainy character of crystals—which determines their hardness and other mechanical properties—and give engineers a new tool for analyzing the wear of metal parts. “If the theory is correct, it's very important,” says Michael Zaiser, a theorist at the University of Edinburgh, U.K.

    Within a crystal, atoms snuggle into orderly planes like checkers filling a checkerboard, and the planes stack to form a regular three-dimensional (3D) structure. A real crystal also contains many threadlike dislocations, which arise when, for example, one plane of atoms wedges partway between two others. The edge of the extra plane then creates a 1D irregularity running through the crystal. These 1D dislocations coalesce to form 2D walls that separate the grains and cells.

    Mosaic.

    Within the orderly arrangement of atoms in a crystal, 1-dimensional dislocations (inset) coalesce to form the 2-dimensional boundaries of grains, like these in copper.

    CREDIT: DOITPOMS, UNIVERSITY OF CAMBRIDGE

    Physicists have tried to simulate that process in computer models that track the motion of each atom. But those simulations work only for idealized 2D crystals one plane of atoms thick, Zaiser says. Simulating a 3D crystal is “one of the most computationally intense simulations known to man,” he says.

    So Surachate Limkumnerd and James Sethna of Cornell University took a different tack. They described the atoms with a continuous “tensor field” that quantified how far and in which direction each one had been displaced from its position in the ideal crystal. A tensor field roughly resembles the arrow-filled weather maps on which forecasters plot wind directions and speeds. Each dislocation corresponds to a tornadolike eddy within the field.

    Using a computer, the researchers then calculated how, starting from random variations, the tensor field interacts with itself and evolves. Wherever dislocations accumulate, stress within the crystal can jump significantly from one side of the accumulation to the other. The “stress jump” attracts more dislocations in a runaway process that mathematically resembles the formation of a shock wave. Ultimately, the dislocations squeeze into sharply defined walls, the researchers report in a paper to be published in Physical Review Letters.

    Other physicists had attempted continuum models as much as 50 years ago, but all failed to produce walls. Their mathematical approaches led to vexing infinities that the tensor field avoids, Sethna says. Even so, Sethna and Limkumnerd had to employ special computational tools to deal with the slightly less troublesome jumps.

    The model is an important first step, says Stefano Zapperi, a theorist at the National Institute for the Physics of Matter in Rome, Italy, but it doesn't yet account for some key ingredients. For example, physicists know that grains, which form when a crystal solidifies, generally subdivide into cells only when a crystal is stressed. In the model, the dividing happens spontaneously. “The key would be to put something more realistic into it and see if you can make predictions that you can test experimentally,” Zapperi says.

    Sethna agrees and says that, for example, including the tendency of dislocations to tangle might impede the spontaneous division of grains. Still, at this stage Sethna is encouraged that he and Limkumnerd have managed just to hit a wall.

  6. UNIVERSITIES

    Austria's Bid for an Instant MIT Meets Opposition From Researchers

    1. Gretchen Vogel

    A plan to create a new elite university in Austria that once had the backing of politicians and top scientists has lost the support of many prominent researchers. On 2 March, the Austrian cabinet approved a law that will establish the Austrian Institute of Science and Technology, with $545 million in funding over 10 years. But early backers of a plan to draw world-class researchers to a technology-focused graduate school have withdrawn their support over what they say are overly political decisions on the new institute's location and direction.

    The bandwagon to create an institution may be “unstoppable,” says molecular geneticist Barry Dickson of the Research Institute of Molecular Pathology in Vienna. But without more input from scientists, he says, the school has no chance of reaching the world's top ranks. “It's a completely missed opportunity,” he says.

    Under pressure.

    Scientists say Austrian education minister Elisabeth Gehring's plans for an elite university are driven by politics.

    CREDIT: GERARD CERLES/AFP/GETTY IMAGES

    Austria is the latest country to attempt to boost its research profile by creating a new institution on the model of the Massachusetts Institute of Technology in Cambridge. Germany and France have also launched elite funding schemes, and politicians in the European Union are keen to create a European Institute of Technology (Science, 3 March, p. 1227).

    Many European universities have a sprinkling of world-class research groups, says physicist Anton Zeilinger of the University of Vienna, but none has the critical mass of America's top institutions. Two years ago, Zeilinger proposed starting a new graduate-level institution, which he hoped would provide healthy competition for Austria's existing universities, he says.

    But scientists and politicians often have different goals. Those differences came to a head in mid-February when the government announced that the proposed school would be located in a small village 45 minutes outside Vienna on the campus of a psychiatric hospital. Critics say this ignored two other locations that scientists preferred and that were within the city, closer to existing research institutes. Dickson and others say political considerations weighed in favor of Gugging, where the local governor is a political ally of the national government.

    The problems go beyond the location, Zeilinger says. It is crucial, he says, to bring in independent international experts to guide the university's first steps. But the steering committee members announced last week are almost exclusively Austrian, and most have reason to protect their current universities and institutes, Zeilinger says: “It's like asking the heads of Skoda and Mitsubishi to create a new Mercedes.”

    International experts will guide the new school's scientific direction, says Jürgen Mittelstrass, head of Austria's Science Council and a professor of philosophy at the University of Konstanz in Germany, who will head the national steering committee. He agrees that the Gugging site “is not optimal.” But after national elections this fall, he says, it may be possible to develop a second campus nearer the city.

  7. U.S. SCIENCE POLICY

    Legislator Wants NSF to Offer $1 Billion Energy Prize

    1. Jeffrey Mervis

    Could a $1 billion prize help end the U.S. addiction to foreign oil? Representative Frank Wolf (R-VA) thinks it might. Last week, he urged the National Science Foundation (NSF) to raise such a prodigious amount from private sources and then give it to scientists offering ideas on how to make the United States energy independent.

    “Why not challenge industry and private foundations to come up with $1 billion?” Wolf asked NSF Director Arden Bement at a 2 March hearing on the agency's 2007 budget request. Singling out the billions for public health research from the Bill and Melinda Gates Foundation as an example of how philanthropists are eager to support technological solutions to societal needs, he speculated that many organizations would be willing to donate to a program run by NSF's world-class system of merit review. “I think you should try to raise the money by the end of year. … And I'll put some language into your bill” that would allow NSF to move forward, he said.

    The audacious proposal may force modifications in a plan NSF has been developing in conjunction with the National Academies on earlier orders from Wolf's spending panel, which has jurisdiction over NSF and several other science agencies (Science, 2 December 2005, p. 1417). NSF has already critiqued one draft of a proposal to stimulate innovative research, Bement told Wolf, and expects a second version in a few weeks. “Our plan was to inaugurate the program in 2007 and award the first prizes in 2008,” Bement explained.

    Jackpot.

    Representative Frank Wolf wants NSF to think big.

    CREDIT: CHRIS MADDALONI

    Without presuming any dollar amount, the academies' Stephen Merrill says that body's report examines “how to make a splash in terms of selecting the topics, advertising it, and the ground rules for the competition. The idea is to induce a solution to a major problem by getting the community involved.” Merrill says the academies' team was thinking “along the lines of an [Ansari] X Prize,” the $10 million for privately funded space travel won in 2004 by SpaceShipOne.

    Admitting after the 3-hour hearing that he hadn't worked out the details, Wolf acknowledged that such a privately funded, government-run program would be unprecedented. But he said that shouldn't deter NSF. When NSF Assistant Director Kathie Olsen suggested that “we need to talk to our lawyers to see what we are allowed to do,” Wolf shot back, “I think you can [do it].”

  8. ARCHAEOLOGY

    The End of Angkor

    1. Richard Stone

    The collapse of a great medieval city suggests that environmental miscalculations can spell doom for even the most highly engineered urban landscapes

    SIEM REAP, CAMBODIA—Crouching in the bottom of a gully, Roland Fletcher traces with his finger the beveled edge of a pitted, grayish-red rock. The carved laterite block with a sloping face fits snugly in a groove in the block below. “It's a fancy piece of work,” says Fletcher, an archaeologist at the University of Sydney, Australia. Centuries ago, the people of Angkor built immense sandstone palaces and temples on foundations of laterite, a spongy, iron-laden soil that hardens when exposed to air. In excavations begun last year, Fletcher's team discovered that the half-meter-long block is just one piece of a dilapidated platform extending 20 meters underground in either direction. The platform appears to be the remnants of a massive spillway, possibly used to disperse floodwaters unleashed by monsoon rains. “Nobody had ever seen a structure of this kind here before,” Fletcher says.

    The spillway helps resolve one debate, showing that the majestic waterworks of Angkor—a Khmer kingdom from the 9th to 15th centuries C.E. that at its height encompassed much of modern-day Cambodia, central Thailand, and southern Vietnam—were designed for practical purposes as well as religious rituals. But this singular piece of medieval engineering may also offer clues to a more profound riddle—not because the spillway exists, but because it was destroyed.

    Ever since Portuguese traders in the late 16th century described the lotus-shaped towers of Angkor Wat rising from the forest canopy, people have wondered why the once-gilded temple devoted to Vishnu—humanity's largest religious monument—and the city connected with it were abandoned about 500 years ago. The list of suspects proposed so far includes marauding invaders, a religious change of heart, and geological uplift.

    Beguiling.

    A once-gilded Angkor Wat tower.

    CREDIT: MUTSUMI STONE

    Now Fletcher and his colleagues have new evidence that the very grandeur of Angkor's complex plumbing, the lifeblood of the city, left it vulnerable to collapse. In a provocative new interpretation of Angkor's demise, Fletcher, co-director of the Greater Angkor Project (GAP), a 5-year survey and excavation sponsored by the Australian Research Council, proposes that the trigger may have been a combination of rigid infrastructure, environmental degradation, and abrupt changes in monsoons. He and other scholars caution that the case is not closed. “It's hard to put a finger on any one reason for the collapse,” says Charles Higham, an anthropologist at the University of Otago in Dunedin, New Zealand, whose startling finds at earlier Thai sites are illuminating the origins of Angkor (see p. 1366).

    If the GAP team is right, Angkor—the most extensive city of its kind in the preindustrial world, with a population numbering in the hundreds of thousands in its heyday—would not be the first civilization unraveled by environmental change. For example, many archaeologists now hold that a series of devastating droughts doomed the Maya and their sprawling city-states on the Yucatán Peninsula between 800 and 900 C.E. Angkor's downfall may be a cautionary tale for modern societies on the knife-edge of sustainability, such as Bangladesh. “The lesson to learn from all of this,” says Higham, “is don't abuse the environment.”

    Waterworld.

    (Left) Angkor's ponds, canals, and reservoirs sustained a vast city and its grand temples. (Left to right) The monuments still impress, including heavenly apsaras at Angkor Wat; a statue of a god outside Angkor Thom; and giant faces smiling placidly from the towers of the Bayon temple.

    CREDIT: MUTSUMI STONE

    Seeing the big picture

    On a hazy January morning about 30 kilometers north of Siem Reap, the modern town near Angkor, Donald Cooney banks his ultralight plane hard right and heads toward a stand of trees a half-kilometer away. Soaring over forested lowland crisscrossed with waterways, rice paddies, and traditional wooden houses on stilts, some of the more stupendous Angkorian features are impossible to miss, including a gigantic 1000-year-old earthen reservoir called the West Baray, 2.2 kilometers wide and 8 kilometers long. Dozens of immense stone temples reflect Hindu cosmogony; the temples represent Mount Meru, the mythical home of Hindu gods, and the moats represent encircling oceans. Bas reliefs on sandstone facades depict everyday scenes—two men bent over a chessboard, for instance—as well as sublime visions such as the apsaras, alluring female dancers in elaborate headdresses who served as messengers between humans and the gods. Yet much of the kingdom remains inscrutable, like the giant faces that stare serenely from the towers of the Bayon in Angkor Thom, the walled heart of the kingdom.

    Cooney, a pilot based in Knoxville, Tennessee, takes a hand off the control bar and gestures toward a thicket of banyan trees. “Do you see the temple?” he asks, his voice crackling over the headset. Even from 300 meters up, the umber towers of a walled temple complex built by Yashovarman I in the late 800s emerge from the canopy only when the aircraft is nearly on top of it. “It's easy to see how so much of Angkor was hidden from view for so long,” he says.

    Cooney's flights have helped the 30-person GAP team chart new Angkorian features, such as canal earthworks that are easy to overlook on foot. “It's ground-truthing from the air,” says Fletcher, who co-directs the $700,000 project with Sydney colleagues Michael Barbetti and Daniel Penny, as well as Ros Borath—a deputy director general of the APSARA Authority, the Cambodian agency that manages Angkor—and Christophe Pottier of the French Research School of the Far East (EFEO).

    Although archaeologists have long marveled over Angkor's sculptures and temples, the aerial views have been particularly revealing of the extensive waterworks that sustained them. In 1994, a radar snapshot from the Space Shuttle Endeavor espied eroded segments of the Great North Canal, which shunted water from the Puok River to two reservoirs. Then a few years later, archaeologist Elizabeth Moore of the University of London used radar to spot undiscovered Bronze Age and Iron Age settlement mounds at Angkor.

    Some epic legwork has also revealed the transformation the medieval Khmers wrought on the landscape. In remote sensing and ground surveys conducted on foot in the 1990s, Pottier, an architect and archaeologist, mapped hundreds of hitherto unknown house mounds and shrines clustered around artificial ponds, called water tanks.

    For Pottier, the surveys were an epiphany. “The people of Angkor changed everything about the landscape,” he says. “It's very difficult to distinguish what is natural and what is not.”

    Practical minded.

    Roland Fletcher, on the bank of the West Baray, argues that Angkor's reservoirs were for irrigation and flood control, not just rituals.

    CREDIT: R. STONE/SCIENCE

    That transformation was extensive, as Fletcher, a specialist on the growth and decline of settlements, and University of Sydney graduate student Damian Evans learned by scrutinizing NASA radar images commissioned by GAP. They found Angkorian dwellings and water tanks scattered across roughly 1000 square kilometers and connected by a skein of roads and canals, many now barely discernible.

    The surveys also revealed the outlines of the ingenious water-management system, centered on three great reservoirs, or barays. A labyrinth of channels north of the barays and of the complexes of Angkor Thom and Angkor Wat diverted water from the Puok, Roluos, and Siem Reap rivers to the reservoirs (see map on p. 1367). The system “brought large amounts of water to a halt and then bled the water off into other channels as required,” explains Fletcher. Canals leading south and eastward from the barays dispersed the water across the landscape, for irrigation and to blunt seasonal flooding. This allowed the growth of a vast urban complex: a low-density patchwork of homes, temples, and rice paddies.

    Angkor's growth, and the king's power, depended on sustained rice yields. “If the king runs short of rice, he'd have to go cap in hand to other Khmer lords in the kingdom,” says Fletcher. Reliable yields required ample water at the right times of year. Angkor's water system, therefore, was the wellspring of power for its rulers.

    Surprisingly—and frustratingly—the roughly 1200 inscriptions in Sanskrit and Khmer chiseled on Angkorian walls are mum on the water system. “They're full of references to boundary stones and land ownership, but virtually silent on water issues and water rights,” says Higham. Apart from the inscriptions, not a single written Angkorian word has been recovered. The oldest inscribed palm leaves, a likely medium for records, date from the early 18th century.

    Angkor's inscriptions also betray nothing of the kingdom's decline. By the 14th century, “we really don't know what's going on in Angkor,” says Fletcher. Siamese annals recount how an army from a nearby kingdom seized Angkor in 1431. Why the city was ultimately abandoned is an enigma—although the consequences must have been devastating. “When a low-density city collapses,” Fletcher says, “it takes out the entire region.”

    Angkor's past has remained mysterious in part because Cambodia's grim recent history deterred research here. Civil war, the brutal reign of the Khmer Rouge, and finally the invasion of Vietnamese forces turned Angkor into a no-go zone for nearly 20 years. Although the heritage park with the major monuments is safe for tourists, some terrain north of the barays still has landmines and unexploded ordnance. “You can't go bushwalking here,” Fletcher says. Fortunately, the warring sides left Angkor largely untouched.

    Then when Pottier reopened EFEO in 1992, the emphasis was on restoring the temples. Centuries of neglect had turned some complexes into tumbled ruins, whereas others required urgent measures to stabilize them or restore sandstone facades. More than 20 teams from around the world are working here, says APSARA archaeologist So Peang. He points to masons repairing a 12th century causeway that bisects one of Angkor Wat's moats. “Many blocks have decayed. Rains wash away the sands,” he says.

    The vital repairs, not to mention efforts to interpret the structures and inscriptions, have conspired to keep attention riveted on the monuments. “Archaeologists here have tended to focus on what they can see,” Fletcher says. “Imagine trying to learn about life in New York City by only examining its churches.” As a result, says Pottier, “Huge parts of the site remain complete blanks.”

    For that reason, one can stumble upon hidden treasures. Walking on the bank of the East Baray, Fletcher spots a triangular, darkgray object in the sandy grass. He picks up the palm-sized stone fragment and points to some squiggly lines. “It looks like old writing,” he says. An EFEO expert later confirms that the inscription is from the reign of Yashovarman I. “So much here is just waiting to be discovered,” Fletcher says.

    Going with the flow

    On the western edge of the Mebon, an artificial island in the middle of the West Baray, a tangle of grass and vines hides some laterite foundations. Seventy years ago, during the dry season, a villager looting the Mebon stumbled upon part of a gigantic bronze torso jutting from the muck near the foundations. He alerted an EFEO curator, explaining that the Buddha told him in a dream that he was buried in the Mebon and couldn't breathe. French excavations later unearthed the 2-meter-tall head and shoulders of a statue of Vishnu.

    Beyond the baray, a swelling red sun is just meeting the horizon. “Imagine the rays of the setting sun glinting off Vishnu,” says Fletcher, standing beside the remnants of the temple wall. Pressure from the reservoir's water column would have forced water through the base of the statue and out of Vishnu's navel. Pollen grains preserved in mud inside the temple show that lotus plants flourished in the pond gracing either side of a causeway leading from the temple to the statue.

    A controversy has simmered over whether the magnificent Mebon and West Baray were brought into being solely to inspire awe. Some advocates of the purely ritual argument long claimed that no canals exited the massive reservoir—so how could it have been used for irrigation?

    In the last few years, the GAP team has amassed new details on the vestiges of outlets, some lined with laterite blocks, from both the West and East Barays. To many experts, it's now beyond dispute that the reservoirs were used to store water for irrigation during the dry season and possibly to prevent flooding of houses and fields. “I'm really impressed with what the GAP team is doing,” says Yale University anthropologist Michael Coe, an expert on the Maya and Angkor civilizations. They “have pretty much laid this debate to rest.”

    But the question remains as to how Angkor's endgame played out, as scholars over the years have engaged in a lively Angkorian version of whodunit. Some experts hold that shifting economic, political, or religious winds trimmed Angkor's sails. A “building orgy” of Jayavarman VII, who in the late 12th century ordered the construction of numerous temples and Angkor Thom with its then-gilded Bayon, might have emptied the kingdom's coffers and thus reduced its influence. Another possibility is the growth of maritime trade, with centers of wealth shifting south, closer to the sea. Or perhaps Angkor's star dimmed when Theravada Buddhism and its tenet of social equality began to eclipse Hinduism in the kingdom in the 13th and 14th centuries.

    A prevailing view is that crop yields declined precipitously. Nearly 30 years ago, EFEO researchers Bernard-Philippe Groslier and Jacques Dumarçay speculated that the waterways and barays filled with silt, choking off irrigation during the dry winter months. The mechanism might have been deforestation, as fields were cleared for planting to feed a booming population—making Angkor a victim of its own success.

    To test these ideas, Fletcher and others set out to unravel the details of Angkor's canals and barays. They found a number of clues hinting at problems with the grand waterworks. Engineering flaws may have doomed the East Baray, at least. “By modern engineering standards, it was a total failure,” says Heng Thung of the Regional Centre for Archaeology and Fine Arts in Bangkok, a specialist in satellite data. To construct the baray, workers simply piled up earthen dikes on the sides. A canal diverted water from the Siem Reap River to the baray, but because the reservoir's bed was no deeper than that canal, the baray was perpetually shallow during the dry season. Water would have evaporated rapidly when the land is thirstiest.

    The engineers got smarter when they built the West Baray a century later. This reservoir was excavated in places by as much as 1 meter, presumably deep enough to retain water throughout the dry season. What doomed the West Baray, Thung asserts, is something that Khmer engineers or astrologers could never have foreseen: geological uplift. He says the beds of the Siem Reap and other rivers unmistakably deepened during the Angkor era. This must have occurred as the upward movement of the crust gradually raised the flow gradient, making the meandering rivers run faster and cut deeper. River levels would have decreased relative to the surrounding land, until eventually the rivers were too low during the dry season to feed into the West Baray. “When the water was needed, the canals couldn't supply the reservoir,” Thung says.

    Heart of the kingdom.

    Canals diverted rivers in the north to the West Baray, shown here, and other giant reservoirs.

    CREDITS: L. CREVELING/SCIENCE; MUTSUMI STONE

    Whatever the problems with the barays, some researchers contend that their importance for irrigation has been vastly overstated. The engineered system would have provided water to grow enough rice to support between 100,000 and 200,000 people, less than half of the presumed population. The land between the barays and the Tonle Sap, a lake south of Angkor, is so flat that it's hard to imagine large amounts of water supplying a broad expanse of irrigated rice land, says archaeologist John Miksic of the National University of Singapore and an expert on early Indonesian cultures. Most of the populace tended bunded rice paddies that captured water during the monsoons or grew rice in saturated soil left after monsoon floodwaters receded.

    Thung, Fletcher, and others do not dispute that baray-fed irrigation alone would not have sustained the populace. Rather, they suggest, the barays provided extra capacity that could have ensured survival rations during a poor harvest. The irrigation system “may have been a risk-management strategy for a bad monsoon year,” Fletcher says—a strategy that would have failed if the barays didn't fill. Another practical purpose of the barays might have been flood control by diverting waters from swollen rivers: “Insurance policies maybe, in case the monsoons were heavy,” Fletcher says. He proposes that the great embankments and canals are central features of an artificial wetland aimed at reducing the risk of flood damage.

    Remarkably, the GAP team is the first to attempt a comprehensive assessment of Angkor's climate and waterworks. Penny, an expert on past climates, is analyzing pollen grains to uncover shifts in vegetation cover. From this he hopes to reconstruct changes in land use during Angkor's waning centuries. So far, he says, results indicate that Angkor's demise was “patchy, both over time and space,” undercutting traditional explanations for the city's last days. Other scientists are focused on the canals and barays—and tackling the perplexing riddle of the spillway.

    Dowsing for the truth

    The spillway might never have come to light if Khmer Rouge laborers hadn't dug an irrigation trench through it. Around the end of the 9th century C.E., with Angkor blossoming, engineers excavated a long canal that altered the course of the Siem Reap River, diverting it southward to the East Baray. The spillway extends westward from the northern end of the canal and would have functioned, Fletcher infers, to protect that canal from excess flooding, comparable to a bathtub's overflow slot.

    The conundrum is that the spillway's meticulous construction is badly damaged. The Khmer Rouge trench has largely eroded away; the Angkorian workmanship was far superior. Nevertheless, most of the spillway's laterite blocks lie in a jumble under sandy soil. “It was torn apart,” says Fletcher. It's possible, he says, that an engineering flaw caused the spillway to give way. But Angkorian structures were built to last, which propels Fletcher toward a different conclusion. “It seems they ripped the spillway out themselves,” he says. “Perhaps something had gone wrong.”

    Fletcher tends to see the hand of necessity, not neglect. He hypothesizes that the structure was damaged by flooding, then dismantled for its materials, after which Angkor workers buried the ruins to prevent the diversion canal from breaking out of its channel and flowing west.

    The story of the spillway and other clues from the GAP team's work indicate that over the centuries, Angkor's vaunted water system grew ever more complex to support the sprawling city. “We know that something was going wrong, mechanically, with their water system,” Fletcher says. For instance, one of the great southern canals was filled with cross-bedded sand, indicating considerable and rapid water flow as well as sedimentation. “The sand buried the canals,” he says. The water infrastructure “became so inflexible, convoluted, and huge that it could neither be replaced nor avoided, and had become both too elaborate and too piecemeal.”

    Mapping in style.

    Donald Cooney's bird's-eye views of Angkor and its temples (top) have helped researchers detect subtle features, such as eroded canal earthworks.

    CREDIT: R. STONE/SCIENCE

    The more complicated and delicately balanced the system grew, the harder it would have been to compensate for unusual events, such as extreme flooding or drought. “They engineered a completely artificial environment, and it was a fragile environment,” Pottier says.

    Add climate change to this volatile mix, and you have a recipe for disaster. The GAP team is probing whether monsoons became “really erratic” during the Little Ice Age, between 1300 and 1600 C.E. There's good evidence that cooling in the Northern Hemisphere not only weakened monsoons in mainland Southeast Asia during this period but also triggered sharp declines in crop yields in Europe. William Boyd, a geologist at Southern Cross University in Lismore, Australia, who's collaborating with Higham, finds GAP's scenario reasonable; he suspects that the Angkor region would have become drier.

    The idea is “really intriguing,” says archaeologist Miriam Stark of the University of Hawaii, Manoa, who has studied the pre-Angkor Funan kingdom of Cambodia's Mekong delta. But archaeologists say more climate data are needed. “A definitive answer,” says Miksic, “would require a study of the ecology of the Tonle Sap Basin over the past 2000 years.”

    Fletcher concurs, and he and Penny hope to receive permission from Cambodian authorities to go caving in search of evidence. Stalagmites add new layers every year; the isotopic chemistry of the layers captures a record of climatic conditions during accrual. (Stark and Paul Bishop of the University of Glasgow hope to gather similar data from caves in the Mekong delta region in the coming year.) Deciphering the isotope record in suitably old stalagmites should yield insights into past climate. Other evidence could be gleaned from changes in vegetation or lake water levels, and Chinese trade records, says Boyd.

    As Angkor was rising, halfway around the world a similar loss of equilibrium brought the Maya to their knees. Overpopulation and environmental degradation had weakened their Mesoamerican cities. Beset by droughts and a “paroxysm of warfare,” the civilization crumbled, Coe says. “The demise of Angkor is directly comparable to the great Maya collapse,” he says. And it could happen again. “When populations in tropical countries exceed the carrying capacity of the land, real trouble begins,” Coe says.

    Fletcher says there are lessons for developed nations as well. He compares Angkor's plumbing woes to modern cities having to cope at great cost with extensive, decaying sewers or cumbersome road systems.

    On their quest to understand the end of Angkor, the GAP team will continue to excavate and analyze deposits from its water features and reconstruct its environmental history. Angkor, says Thung, “is a never-ending story.” Or, rather, it's an ending often rewritten, and with a lesson for society that gets gloomier each time.

  9. ARCHAEOLOGY

    Local Elites Cast New Light on Angkor's Rise

    1. Richard Stone

    PHIMAI, THAILAND—In a square pit that could swallow a two-story house, a dozen skeletons are seeing the light of day for the first time in 20 centuries. Two adults have more than a dozen seashell bangles on each arm, and a third has a pair of marble bangles. In one corner, small painted clay pots contain infant bones. Above each skull, of adults and children alike, lies a single bivalve shell, probably representing fertility or rebirth, says anthropologist Charles Higham, who is excavating the Ban Non Wat site outside the city of Phimai.

    CREDIT: R. STONE/SCIENCE

    At the edge of the pit, Higham points to a string of pots jutting from the soil below the layer of the skeletons. “These are almost certainly from a ‘superburial,’” he says: an elite grave brimming with shell and marble jewelry and bronze tools and ornaments. After a few more days of digging earlier this month, his 60-strong team of academics, Thai laborers, and volunteers from the conservation nonprofit Earthwatch International capped their field season by unearthing a clutch of ritualistic, princely burials. These wealthy graves date from the Early Bronze Age, more than 18 centuries before the civilization of Angkor rose to greatness.

    Such early riches are helping to rework views of Angkor's origins. Archaeologists long thought that the import of Indian culture between 200 and 400 C.E., during the Iron Age, transformed scattered communities of benighted farmers into civilized societies. A smattering of Bronze Age digs in Southeast Asia had yielded remarkably few grave goods, creating a picture of farmers and fishers eking out hardscrabble lives. Elsewhere in Asia and in Europe, meanwhile, the advent of metalworking in the early Bronze Age had clearly widened the gap between elites, merchants, and commoners. But Higham has uncovered a very different story.

    Rewriting history.

    Charles Higham's team has uncovered rich early graves, as shown by a pot from a Bronze Age superburial next to his left knee.

    CREDIT: R. STONE/SCIENCE

    From a patch of land half the size of an Olympic swimming pool, his team over five field seasons has unearthed 470 graves spanning the Neolithic to the Iron Age, from 2200 B.C.E. to 500 C.E. Most spectacular are the 3000-year-old superburials. The team's largely unpublished findings reveal that Southeast Asian societies were stratified into elite classes more than 1000 years before Indianization began. “By the Bronze Age, people here were sophisticated,” says Higham, of the University of Otago in Dunedin, New Zealand, whose team includes Otago research fellow Rachanie Thosarat and Nigel Chang of James Cook University in Townsville, Australia.

    Moreover, Higham says, the excavations show that the people of Phimai “were able to control water flow long before the development of Angkor's reservoirs.” Those reservoirs and associated canals were vital to Angkor's power (see main text).

    Higham's work is “pathbreaking,” says archaeologist Miriam Stark of the University of Hawaii, Manoa, who co-directs another dig in the region. Ban Non Wat shows that Southeast Asia's Bronze Age societies were not out of step with the rest of the world.

  10. SAMUEL BODMAN PROFILE

    With Energy to Spare, an Engineer Makes the Case for Basic Research

    1. Eli Kintisch

    As secretary of energy, Samuel Bodman leads a campaign for research that will result in new energy technologies. Even critics find reason to applaud

    Samuel Bodman relishes a challenge. Even before President George W. Bush nominated him in late 2004 to be secretary of energy, the chemical engineer and former CEO of the Cabot chemical giant in Boston, Massachusetts, had decided that the government was underfunding “math, chemistry, physics, and engineering.” But the Administration's 2006 budget request that he inherited called for a 3% cut in the Department of Energy's (DOE's) $3.6 billion Office of Science, the primary federal backer of fundamental physics. Bodman gamely defended that request as in line with “the president's deficit-reduction goals.” But back at the department's fortresslike headquarters in downtown Washington, D.C., he set out not only to reverse the cuts in DOE's basic science but also to lobby the White House for new applied energy efforts.

    Last month, Bodman enjoyed the fruits of his efforts: Within a span of a week, Bush devoted an unprecedented nine paragraphs of his State of the Union Address to research and science education and proposed a 14% increase in the 2007 budget for DOE's Office of Science. A nuclear energy initiative drew mixed reviews, and environmentalists applauded the Administration's belated endorsement of solar power and biomass programs (see table, below).

    Bowling partners.

    Speaking at DOE's National Science Bowl, Samuel Bodman has given Office of Science Director Raymond Orbach (left) an enhanced role in decision-making during his first year as energy secretary.

    CREDIT: DOE

    Overnight, Bodman had changed from faceless bureaucrat to a hero of science. “He has his values at the right location,” says nuclear physicist Konrad Gelbke, director of DOE's National Superconducting Cyclotron Laboratory at Michigan State University in East Lansing. “Our last secretary was also an advocate for science, but this is in a different way: hands on,” said Office of Science Director Raymond Orbach last year about a grueling 2-hour budget briefing session with Bodman.

    The self-effacing 67-year-old says he doesn't relish the spotlight: “I don't view myself as a role model.” He credits his success partly to hard work: Even before he was confirmed as DOE's 11th secretary, he devoured several fat three-ring briefing binders describing the $24 billion behemoth he was about to manage, which has responsibility for everything from the nation's nuclear weapons arsenal to appliance standards. And he's quick to spread the credit around. “I'm a good judge of horseflesh,” he says, noting that Orbach has been nominated for the additional title of undersecretary of science, a position Bodman successfully lobbied Congress to create last year. But he is as results-oriented as any CEO, targeting “areas that are best positioned to yield results in our lifetime, more specifically, in my lifetime.”

    Although energy scientists aren't willing to bet that Bodman will be able to transform an energy industry whose fundamental technologies have changed little in 30 years, they think his academic and energy qualifications give him a better shot at succeeding than his predecessors. That roster includes a dentist, a lawyer, and two former senators with no technical background. Former CIA director and DOE official John Deutch says Bodman may be “the most qualified secretary we've ever had.” Bodman, they argue, represents the best shot in decades at changing how America uses energy.

    Follow the money

    Trained as a chemical engineer at Cornell University and the Massachusetts Institute of Technology (MIT), Bodman was quickly attracted to the fledgling world of venture capitalism. An associate professor at MIT in the 1960s, he simultaneously worked at the Boston-based American Research and Development Corp., among the first venture capital companies to benefit from the emerging U.S. academic research juggernaut. Bodman then took a job assessing energy and chemical technology for Fidelity Investments' nascent venture unit, spending more than a decade at the mutual fund giant and rising to chief operating officer. As Cabot CEO, he won plaudits as the $2 billion company expanded into natural gas and electronics. With Fidelity, he met Don Evans, a Bush family friend who became commerce secretary and recruited Bodman as his deputy. Bodman oversaw the department's research portfolio, which includes the National Institute of Standards and Technology (NIST) and the National Oceanic and Atmospheric Administration.

    Yet despite a career focused on technology—” I'm an engineer, not a scientist,” he's quick to remind reporters—Bodman often talks about the need to beef up U.S. fundamental research. And he's extremely grateful for the $2200-a-year National Science Foundation (NSF) fellowship that put him through graduate school in the early 1960s. “What I'm concerned about is that America retain leadership, that America continue to be the place that offers the maximum opportunity for a young scientist or a young engineer … to participate in the great discovery process that is science,” he told Science in an interview last week in his well-appointed seventh-floor office.

    Bodman is pushing the president's new American Competitiveness Initiative, which promises a 10-year doubling of basic science funding in DOE's Office of Science, NSF, and NIST's core lab programs. On his office coffee table sits a well-worn copy of an October report from the National Academies on bolstering U.S. leadership in science (Science, 21 October 2005, p. 423).

    His corporate and technical experience helps him understand how basic science can feed into new energy technologies, Bodman says, and he's quick to challenge proposed solutions. Joe Jones of Skyonic, a carbonchemistry start-up in Austin, Texas, says during a recent meeting Bodman “snapped back between chemical engineering professor and board of director; … [it was] the equivalent of my [graduate school] orals.”

    Befitting a former corporate manager, Bodman likes to set specific market goals. For biofuels, he wants to improve the conversion of cellulose—think corn waste or wood chips—into ethanol for cars, making it competitive with gasoline in 6 years. Starch in corn kernels is currently converted into the fuel and used as an additive in millions of U.S. autos, but DOE's Doug Kaempf says a 30-fold drop in the cost of enzymes that convert cellulose to sugar helped persuade Bodman to boost biofuels research dollars by 65%—focusing on fermentation. Similarly, progress in photovoltaics persuaded Bodman to boost applied solar work such as silicon manufacturing and crystal growth techniques, aiming to make solar energy as cheap as retail electricity by 2015.

    Growth industry.

    President George W. Bush has requested healthy increases next year for DOE's basic research efforts and several applied programs.

    SOURCE: DOE; (PHOTOS, TOP TO BOTTOM): GETTY IMAGES; CORBIS; PHOTOS.COM (2); MASS.GOV

    Previous DOE attempts to promote similar programs have been rebuffed by a White House with close ties to the energy industry. High gasoline prices helped Bodman this time around, but so did his inside-the-Beltway mettle, lobbyists attest. Former Commerce official Phillip Bond, now with Monster.com, says Bodman repeatedly secured healthy funding requests for NIST labs by describing what its science “meant for the business sector.” From his office window, Bodman can gaze upon the Capitol dome. “That's where the money is,” he says.

    Flying under the banner “work together,” Bodman has declared war on DOE's infamous bureaucratic stovepiping. Scientists involved with DOE's supercomputing efforts, for example, say that separate programs connected to weapons and basic science are talking more to one another, with good results. Bodman has also elevated Orbach's role as science adviser to the secretary, consulting with him before deciding to support the National Ignition Facility, a superlaser at Lawrence Livermore National Laboratory in California that faced the budget ax last year. The materials scientist also helped decide the fate of several troubled cleanup sites, giving guidance “as to what kind of glass they were using,” Bodman says. “I think [Bodman] brought back the notion that the head of the Office of Science is going to provide him basic scientific input on general science issues,” says MIT theoretical physicist Arthur Kerman, a longtime DOE consultant.

    That faith in his deputies has ruffled some feathers. In January, Bodman dismissed the top science advisory board at DOE—6 months after it released a report critical of DOE's management of its weapons complex. Senator Carl Levin (D-MI) called the move “troubling,” and longtime DOE adviser and physicist Richard Garwin sees it as “a very bad idea.” Peter McPherson, chair of the now-shuttered group and president of the National Association of State Universities and Land-Grant Colleges, is less concerned. Bodman, he says, “can get input from other sources.” And Bodman says he prefers to receive advice from those “on the payroll.”

    A treacherous path

    Many energy watchers are skeptical of DOE's new priorities. Some experts complain that Bodman, whose entourage uses a limousine and big black SUVs, plays down saving energy. The American Council for an Energy-Efficient Economy says that Bodman's proposed cuts for energy-efficiency research and weatherization programs undermine the president's stated goal of curing “America's oil addiction.” Green groups, in turn, cheer the ethanol studies but say the government could reduce carbon emissions faster by mandating more efficient cars. Citing high fuel prices, Bodman says “there is plenty of sacrifice to go around.”

    The $250 million nuclear initiative, in particular, is a lightning rod for critics. Bodman says results from DOE labs “seem to indicate” potential for advanced recycling of waste, reducing the need for a geologic repository. Critics say that billions could be wasted in a futile attempt to convince the nuclear industry. Others, such as Princeton University physicist Frank von Hippel, question whether the system could work without producing fissile material that terrorists could use to build bombs. Bodman says that effort—and a similar demonstration project on an advanced coal plant called FutureGen—is focused on convincing the industry to eventually buy in. But MIT's Deutch warned in a paper last year that congressional mood swings and a lack of “necessary skills” at DOE have doomed a number of previous demonstration projects, including the Clinch River Breeder Reactor and several synthetic fuel plants.

    Others question the scope of Bodman's vision. Although chemist Nate Lewis of the California Institute of Technology in Pasadena welcomes new solar funding, he notes that poor storage technology means homes with solar panels must draw from the grid at night, suggesting that only transformational advances in photovoltaics and batteries would create true independence. Hoffert says Bodman's new efforts “are a good idea but [are] pitifully small compared to the magnitude of the problem.” National Venture Capital Association President Mark Heesen fears Bodman's employees won't conquer “the mindset that big companies are the only ones who solve big issues,” missing potential breakthroughs.

    Bodman is careful not to oversell the department's various taxpayer-funded gambles, including the nuclear reprocessing initiative, using lingo taken in equal parts from his business and academic backgrounds. “If we do the work and the industry expresses zero interest, either we will try to convince them otherwise, or we won't proceed,” Bodman told Science. After all, he says, “this is research.”

  11. RESEARCH POLICY

    A Dose of Reform to Treat the Malaise Gripping French Science

    1. Martin Enserink

    Two years after protesters launched a massive revolt against government science policy, France has adopted a law that promises to reform the establishment

    End of the road.

    Researchers formed a nationwide movement to protest inadequate pay and a stagnant work environment. The government response, due to be voted on this week, wins few plaudits.

    CREDIT: FRED DUFOUR/AFP/GETTY IMAGES

    PARIS—Just 700 protesters showed up for a final march against the French government's research policy last week, according to the police. Like so much in this uprising, the number of marchers is disputed: The organizers claim there were at least 2000. It was by any estimate a far cry from the tens of thousands of angry researchers and supporters who took to the streets 2 years ago to air grievances about the system. And last week, the protest ended in anticlimax: After walking the short distance from the Musée d'Orsay to the National Assembly, the crowd dissipated quickly into the evening rush hour; it didn't even make the TV news.

    The object of the protesters' ire—a plan drawn up by civil servants to infuse new life into French research—is also coming to a quiet conclusion. A bill authorizing reforms was expected to pass the full National Assembly easily on 7 March and was slated to be approved by both legislative houses on 16 March after differences are ironed out. The package includes a raft of measures aimed at luring young people into labs and making innovation the engine of a flagging economy. But few except education and science minister Gilles de Robien and minister delegate François Goulard, who shepherded the bill to a vote, seem excited about it.

    The powerful trade unions and the protest movement Sauvons la Recherche (Let's Save Research, or SLR), which organized last week's protest, criticize the plan for falling short of their goals. Others cite its positive elements: The research budget will grow from €19.9 billion in 2005 to €24 billion in 2010. Along with providing more money, the new law attempts to simplify research management and empowers a new National Research Agency (ANR) to dole out funds for projects based on merit reviews, a novelty in France. But the scientific community had hoped for a bigger financial boost. “I have very mixed feelings,” says physicist Edouard Brézin, president of the Academy of Sciences, who says the bill bespeaks a “lack of ambition.”

    Few dispute that French science is, as an academy panel chaired by the academy's permanent secretary Jean-François Bach put it last year, “in a serious crisis.” Studies have concluded that it is lagging behind the rest of Europe and the United States, based upon the declining quantity and quality of research outputs well as the small number of new patents and biotech start-ups that stem from French research. Low wages and scarce lab resources have made the profession unattractive for young people. And the prime advantage of joining the vast scientific civil service—security for life—hardly stimulates creativity.

    Government labs such as the mammoth CNRS and INSERM, where most research takes place, are at arm's length from higher education, and university scientists are overburdened with teaching tasks, the academy report concluded. Bureaucratic rules waste precious time and money, too, says Bernard Meunier, who quit as CNRS president in January to protest “excessive” bureaucracy and now leads Palumed, a biotech firm developing antimalarials and antibiotics.

    Voice of protest.

    Sauvons la Recherche spokesperson Alain Trautmann.

    CREDIT: JACK GUEZ/AFP/GETTY IMAGES

    Many successful scientists opted out of the French system. Molecular biologist Catherine Dulac, who runs a lab at Harvard studying olfactory signaling, says she was determined to return to France after a postdoc job in the United States—until she realized how limited her resources would be. “It would have been scientific suicide,” she says. Attracting fresh foreign blood to France is even more difficult than retaining French talent, says Brézin.

    Some labs have tried to bring about change on a small scale. The Curie Institute in Paris, for instance, lures top researchers by offering them better paid, 5-year contracts, and more money to spend on equipment and support staff. It can do so because, as a foundation, it is blessed with both public and private money, says Curie Director Daniel Louvard. However, strict labor laws put limits on its flexibility.

    Discontent reached a boiling point in early 2004, after the government made cuts in the science budget and proposed to replace 550 permanent jobs with temporary contracts. More than 3500 lab leaders threatened to stop performing their administrative duties, and streets around the country filled with protesters in lab coats (Science, 13 February 2004, p. 948). Surprised by the scale of the backlash, the government backed down, and President Jacques Chirac promised a “Pact for Research.” The scientific community organized a nationwide debate, culminating in a 2-day meeting in Grenoble and a consensus wish list (Science, 5 November 2004, p. 956).

    Geochemist Claude Allègre, who served as science minister in a Socialist cabinet from 1997 until 2000, says the scientists' movement accomplished less than it might have because it engaged in a “naïve” debate about structural changes it wanted in the science system. “They lost 2 years,” Allègre says. “Money, money, money—that's the only thing that's important at the moment.” But Brézin notes that scientists had their recommendations ready in November 2004; it's the government that kept postponing the bill, in part because of a complete cabinet reshuffle after a public vote rejected the European constitution in May 2005.

    Still, money remains a key issue. The budget increase to €24 billion—which would be even higher if Goulard can deliver on a commitment, made during the debate, to correct for inflation—will help pay for 3000 new jobs. “The hemorrhage has stopped; that's positive,” says SLR co-founder and spokesperson Alain Trautmann. But Trautmann and other critics say the bill falls far short of what's needed to revamp anemic government labs. Roughly one-third of the new money comes in the form of tax deductions for industry, which, Brézin notes, does little for basic research. To his critics' surprise, Goulard also made a turnaround and promised to try to raise Ph.D. students' salaries to 1.5 times the minimum wage. But it's a commitment that could easily be forgotten if there's no money or if Goulard is replaced, Trautmann says.

    The law authorizes new “Regional Centers for Science and Education” to bring scientists from government institutes and universities together, but the plan doesn't go far enough to provide the needed relief for university research, says Bach. Researchers are also “nervous” about the bill's vagueness, he says; for example, it's not clear whether a new High Council for Science and Technology—which researchers had lobbied hard for—will be truly independent or merely decorative. Goulard sees a major advance: “Never, and I mean never, has so much been done for French science,” he said last week.

    Opinions are divided, meanwhile, about the new grants agency ANR, which started operating last year with temporary authority. Bach believes it will create a new way to support talented young people, provided it stays free of political interference. But SLR and the trade unions oppose the new agency, which they worry will not improve flexibility as much as it will reduce certainty for the average researcher. Indeed, one reason SLR lost steam, Meunier says, is that it had become increasingly aligned with the trade unions, which argue for more money but have opposed substantive change. Despite the banners, the balloons, and the whistles, the research unions tend to be conservative, protecting the interests of those inside the system with good jobs at the expense of younger people, he says.

    Trautmann acknowledges that there has been a “convergence” between SLR and the unions and that it has caused some early members to turn their backs on the movement. He says he isn't happy with this himself, as SLR was started primarily to address the plight of young scientists. “We don't want to be a new union,” he says. Now that the landmark reform bill has passed, SLR will decide on own its fate at a general meeting on 11 March. Although Trautmann says he wants to continue “analyzing and communicating” about science policy in some way, he says the group could decide to dissolve.

    For now, most scientists are hoping for better times. If the left comes to power in the 2007 elections, the research budget will get a 10% annual increase, Socialist Party leader François Hollande promised last week.

  12. EVOLUTIONARY BIOLOGY

    Speciation Standing in Place

    1. Elizabeth Pennisi

    Surprising some evolutionary biologists, studies of birds, fish, trees, and insects show that it doesn't take a mountain chain, island, or other geographic quirks to create a species

    Nesting behavior.

    By sneaking into nests of two kinds of finches, the blue indigobird is on its way to splitting into two species.

    CREDIT: MIKE SORENSON

    It's not often that one witnesses speciation in action, but some birdwatchers in Africa may be having that privilege. Michael Sorenson, an evolutionary ecologist at Boston University, and Robert Payne of the University of Michigan, Ann Arbor, have monitored African indigobirds at a field site in Cameroon for the past decade. The opportunistic birds lay their eggs in the nests of different species of finches. The newborn indigobirds then look and act as if they belong there, and as adults, incorporate the twills and whistles of their foster parents into their own mating calls.

    Recently, the researchers observed one species, called the blue indigobird, lay eggs in the nests of both the African firefinch and the Black-bellied firefinch. The resulting indigobirds learned the songs of their respective finches and now seem to have developed into two “races.” Although all the blue indigobirds can still mate with one another—which means the races are not yet distinct species—females prefer suitors who know the same finch song they do. And they pass their preferences on: Female indigobirds that grow up in an African firefinch nest, for example, tend to lay eggs in the same kind of nest rather than in one belonging to a Black-bellied firefinch. “We have a nice example of early stages of speciation in this group,” concludes Sorenson.

    This bird tale, described in an upcoming Behavioral Ecology paper, is one of several recent volleys in the continuing debate over how speciation occurs. For the past 50 years or so, many influential evolutionary biologists, notably the late Ernst Mayr, have held that physical separation among members of a species, such as that caused by the emergence of a mountain chain, typically drives the splitting of one species into two. Populations separated by geographic barriers can't interbreed and eventually evolve into distinct species. Examples of this speciation process, called allopatry, abound.

    Charles Darwin recognized allopatry as a driving force of speciation. But he also thought populations could diverge into separate species in the absence of physical barriers, an idea now called sympatric speciation, or simply sympatry. However, his successors were at a loss to explain how this could happen, and they could find few examples. By 1907, textbooks dismissed sympatric speciation, and 35 years later, Mayr virtually tossed the idea out of modern evolutionary thinking with his strong antisympatry rhetoric. Since then, few researchers have taken sympatry seriously.

    Now the situation is changing fast. The indigobird study, combined with recently published reports of sympatric speciation among cichlid fish and palm trees, have offered compelling new support for the concept. Although some researchers are not yet convinced, sympatric events can now be detected with unprecedented certainty, says evolutionary biologist Axel Meyer of the University of Konstanz, Germany, who led the new cichlid fish study. Even supposedly airtight examples of allopatry have sprouted leaks; a new study questions whether certain mammalian groups arose through allopatry, as researchers have long thought.

    Instead of asking if sympatry occurs at all, “the question has now become ‘How frequently does sympatry underlie the genesis of new taxa?’” says Jeffrey Feder, an evolutionary biologist at the University of Notre Dame, Indiana.

    The case for sympatry

    Sympatry has been slow to catch on in part because it is hard to envision why members of one group in a population would predominantly mate only with each other. “There has to be some sort of assortative mating, or you don't get [species-defining] genetic differences creeping in,” says Kenneth Petren, an evolutionary ecologist at the University of Cincinnati, Ohio. With allopatry, it's simple: Geographic barriers leave individuals little to no opportunity to breed with their peers. But with sympatry, “ecological” barriers—genetic, morphological, or behavioral quirks that lead to changes in food preferences, courtship colors, breeding season, and so forth—cause group members to prefer or have contact with a specific type of mate.

    Sympatry is hard to spot. To find it in a world seemingly dominated by allopatry, evolutionary biologists must identify a place where it is highly unlikely that physical barriers have separated members of a species. They must identify closely related, but nonetheless different, species and measure the amount of “gene flow” between the two species. In sympatry, where some interbreeding occurs throughout the speciation processes, gene flow is rampant, especially at first. As a result, the two species look similar—genetically speaking—except for the particular genes underlying the changes in behavior, morphology, etc., that make the two species different. In contrast, in allopatry, physical barriers essentially cut off gene flow, freeing entire genomes to evolve in different directions. Thus, the pattern of genetic differences provides a key clue about the method of speciation.

    New territory.

    Fruit flies that originally lived off hawthorne trees have now colonized apple trees and evolved a dislike for hawthorne fruit, which may ultimately create a new fly species.

    CREDIT: ANDREW A. FORBES

    One of the oft cited cases of sympatry is a 1994 report by Ulrich Schliewen, an ichthyologist at the Zoological State Collection in Munich, Germany, and his colleagues. They concluded, based on mitochondrial DNA studies, that 11 cichlid species living in a small lake in Cameroon arose sympatrically from a common ancestor trapped in the 2.5-kilometer-wide space. Schliewen attributed this burst of sympatry to the original species evolving in ways that, for example, helped the fish thrive at different depths. Schliewen's work has been widely heralded as one of the best examples of sympatric speciation, in part because it's unlikely that this isolated lake would have been colonized enough times by outside species to create the current diversity, says Feder.

    Backdoor speciation.

    In a Cameroonian lake, the slender Konia cichlid (top) hybridized with another species and gave rise to the fatter, sponge-eating Pungu cichlid (bottom).

    CREDIT: JÖRG FREYHOF

    In 2004, Schliewen described a new twist on the evolution of this tightly knit group of fish. With more extensive genetic testing, he found that at least one of the 11 species arose as a hybrid of two other species, suggesting yet another avenue of speciation among sympatric species.

    Schliewen had few molecular techniques at his disposal when he did his initial work in the early 1990s, which left some people skeptical of the sympatry claim at the time. But in the 8 February issue of Nature, a team led by Meyer and one led by Vincent Savolainen and William Baker of the Royal Botanic Gardens, Kew, in Richmond, U.K., apply new genetic analyses to come up with two additional compelling examples of sympatry.

    Meyer and his colleagues examined two fish species, the arrow and Midas cichlids, that live in an isolated 5-kilometer-wide volcanic lake in Nicaragua. By comparing the species' mitochondrial genes, variable DNA sequences called microsatellites, and other genetic landmarks, the researchers demonstrated that the arrow cichlid evolved from the Midas cichlid fewer than 10,000 years ago. They argue that the lake is too small for this to have resulted from physical separation. Instead, they believe that competition for food may have pushed members of the ancestral species to go in different ways. The Midas cichlid is an algae-eating bottom feeder with a deep body, whereas the arrow cichlid, whose slender shape is built for swimming, often dines on winged insects. Other researchers have shown that the two prefer to mate with their own kind and that when forced to interbreed, they fail to produce young,

    Savolainen and Baker also picked a remote spot to search for sympatry: Lord Howe Island, a 12-square-kilometer speck of volcanic rock 580 kilometers east of Australia. There they studied two indigenous palm tree species, the kentia palm, which is used throughout the world as a houseplant, and the much shorter curly palm. A DNA-based family tree of all the island's palm species indicated that the curly palm descended from the kentia palm about 1 million to 2 million years ago. Although the two species coexist in 20% of the island sites surveyed, the timing of their flowering now keeps them separate, say Savolainen and Baker.

    The pair suggests that soil differences on Howe Island created the ecological barrier that drove this sympatric speciation. Today, kentia palms thrive on the island's basic soil, whereas curly palms stick to acidic soils. Savolainen and Baker suggest that as the kentia palm spread onto different soils, its flowering time was delayed, possibly because the genes needed to adapt to the altered pH affected the transmission of those involved in flowering. The new flowering schedule jump-started the speciation process.

    Castaway.

    Cuban lizards became diverse after the island was partially submerged and divided into isolated islets.

    CREDIT: JONATHAN B. LOSOS

    The studies are “a good beginning” to demonstrating sympatry, says Jerry Coyne, an evolutionary biologist at the University of Chicago, Illinois, who has in the past been skeptical of proposed cases of sympatric speciation.

    Sympatry on the fly

    Some apparent cases of speciation in action, such as that of the indigobirds, are also bolstering the case for sympatry. Back in the 1860s, local farmers noticed that some fruit maggots had switched their mating and breeding grounds from hawthorns, which are native to America, to apples, a domesticated fruit species. A century later, Guy Bush of Michigan State University in East Lansing proposed that this type of ecological separation might be a common mechanism by which fructivore insects diverge into new species. Although not yet genetically distinct enough to be separate species, the apple and hawthorn maggots are proving a strong example of incipient sympatry, says Feder. The two types of maggots have begun to develop some subtle genetic differences. For example, apple maggots are much more likely to have genetic variants that slow egg development, such that their eggs hatch at peak apple season. Feder and his colleagues' recent work also shows that the two kinds of maggots remain separate in part because they are attracted to the odor of their particular fruit and are repulsed by other fruits.

    Other insects seem to be following a similar path to a sympatric split. Last year, Thibaut Malausa, at the Université Paul-Sabatier in Toulouse, France, and his colleagues found very little intermating in the wild between European corn-borers that prefer corn and ones that prefer hop or mugwort, even though all belong to the same species. Further enforcing this reproductive isolation, says Malausa, is that corn-feeding caterpillars of the species emerge as moths later than caterpillars with a hop-mugwort diet do (Science, 8 April 2005, p. 258).

    Judgment calls

    Fans of sympatric speciation are still working to win over many evolutionary biologists. For every researcher who sees a solid example of sympatry, there's a skeptic ready to poke holes in the case. “It's hard to rule out some sort of geographic separation, even if it's microseparation,” notes Petren. Hop versus corn, or apples versus hawthorn, could easily be interpreted as geographic isolation on a small scale, for example. And seemingly sympatric species isolated on islands or in lakes may have divided their territories enough to enforce reproductive isolation, Petren points out. The arrow and Midas cichlids divided their lake by depth; the kentia and curly palms stick to particular soil types. “It's always a tough call since we were not there at the time of speciation,” says Feder.

    Coyne also worries that the genetic evidence of close kinships may be misleading. In the case of the Lord Howe Island palms, for example, the second palm species may have arisen elsewhere. If wind blew some of that palm's pollen to Lord Howe and hybrids resulted, then the intermingling of the genomes of the two species would make them seem more closely related than they really are. “It's a judgment call,” Coyne says. “There are other alternatives that have to be taken seriously.”

    Richard Glor, an evolutionary biologist at the University of California (UC), Davis, has found such an alternative explanation for the diversity of anole lizards on Cuba. Cuba is a relatively small island with 60 species of Anole lizards, and some researchers have proposed that sympatric speciation underlies much of the lizards' diversity. In 2004, Glor and his colleagues analyzed genetic differences among three green canopy-dwelling lizards to determine when the species separated. They concluded that the speciations occurred more than 5 million years ago, at a point when a rise in sea level had broken Cuba into multiple islands. Thus, physical separation, not sympatry, gave rise to the three species, which are reunited on a single island today, says Glor.

    Still, that ambiguity cuts both ways. Some cases of mammalian speciation attributed to allopatry have recently been called into question. UC Davis evolutionary biologist Michael Turelli admits that he had hoped to quiet sympatry sympathizers with a new study, appearing in the March issue of Evolution. He and his former student Benjamin Fitzpatrick gathered data on the ranges of 14 groups of mammals—“where no one thinks that sympatric speciation is going on,” says Turelli.

    The study's rationale was simple: If two closely related mammals arose through geographic isolation as allopatry demands, then they should have ranges that were disconnected, at least early in their evolutionary history. (Over time, these species might expand their ranges such that the two would intersect somewhat.) With sympatric speciation, the opposite should be true, Turelli explains. By definition, sympatric species start off in the same place and only over time do their ranges diverge.

    The analysis firmly established allopatry for gophers but not for two-thirds of the other mammals. “We saw clade after clade where there was no clear signal,” says Turelli. “The punch line is it's less obvious that it's all allopatry all the time.”

    Indeed, even the most fervent fans of allopatric speciation are becoming more open-minded. Just as Mayr did later in his career, Coyne is softening his stance, for example. At least, says Giacomo Bernardi, an evolutionary biologist at UC Santa Cruz, “evolutionary biologists are at last essentially agreeing that sympatric speciation is possible.”

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