# News this Week

Science  23 Jun 2006:
Vol. 312, Issue 5781, pp. 761
1. VOLCANOLOGY

# Scientists Steal a Daring Look at Merapi's Explosive Potential

1. Richard Stone

YOGYAKARTA, INDONESIA—It's an overcast and humid morning on 14 June as Supriyati Andreastuti and two colleagues embark on a routine mission to sample ash on the slopes of Mount Merapi. The researchers with the Merapi Volcano Observatory (MVO) are really scraping: Tarps set out to accumulate ash are barely flecked with gray. That isn't surprising. For several days, Indonesia's most active volcano has been relatively still. Working west across Merapi's southern flank, the trio, a Science journalist in tow, pulls into the Kaliurang Observation Station for a chat with Panut, chief observer. They park their jeep facing downhill, in case a quick getaway is in order.

Panut isn't fooled by Merapi's tranquility. The current eruption may have cooled, he says, but he doesn't think it's over. As if on cue, the seismograph warbles. Huddling around it, Andreastuti and the others infer that a searing avalanche of volcanic rock, dust, and gas—a pyroclastic flow—is tumbling down the 3000-meter-tall mountain a few kilometers to the southeast, toward the Kaliadem tourist area.

Ten minutes pass, then 20. Andreastuti looks worried. “This one's dangerous,” she says. It's impossible to discern from the seismograph how far the lethal clouds are traveling, but she knows that villages in the Kaliadem area are within striking range.

Merapi, the nemesis of Indonesian volcanologists, has roared back to life after a hiatus of 4 years. It began to stir in July 2005 with a swarm of tremors, then started dribbling lava in April. The eruption seemed to be subsiding at the end of last month when a magnitude-6.3 earthquake struck south of Yogyakarta, Java's ancient capital, on 27 May, killing 5780 people. Subsequently, growth of Merapi's lava dome surged. “The earthquake may have increased the ability of magma to move up into the conduit,” says Birger Lühr, an applied geophysicist at the GeoForschungsZentrum in Potsdam, Germany.

Volcanologists are now racing to determine whether the latest uptick in Merapi's activity presages an explosive eruption—“no Krakatoa but … big enough to send pyroclastic flows in all directions,” says Christopher Newhall, a volcanologist dispatched by the U.S. Geological Survey and the U.S. Agency for International Development to assist MVO. Although Newhall emphasizes that the odds of an explosive eruption are low, “we know Merapi is capable of quite nasty things.”

Every few decades, on average, the volcano has a large eruption, and every several centuries it blows its top in a vertical plinian eruption—far more frequently than previously envisaged, Andreastuti and other researchers have found after analyzing ancient ash deposits and historical records. The most recent plinian eruption occurred roughly 500 years ago. Two lesser explosive eruptions in the 19th century killed thousands of villagers on the mountain's slopes; lava dome growth, says Newhall, appears to have preceded both events. By comparison, Merapi's outbursts in the 20th century were relatively tame. A 19th-century-sized eruption could put 80,000 villagers at risk.

Uncertainties abound. Merapi's behavior, as with other open-vent volcanoes, is notoriously unpredictable: Magma rises to the surface, loses some dissolved gases, and bleeds out or builds up in a lava dome. This can lead to pyroclastic flows and dome collapses or—under certain conditions—a gas-driven blast. Like others of its ilk, Merapi “doesn't give you many clues which way it will go,” Newhall says.

Some Merapi eruptions have lasted months; there's no telling when this one will end. For MVO chief Antonius Ratdomopurdo and his staff, this translates as round-the-clock vigilance, and, says Newhall, “a hell of a lot of pressure.”

## Calculated risks

Andreastuti and her team drive east from Kaliurang for 15 minutes to the Merapi Golf Course near Kaliadem, 8 kilometers from the summit. They are hoping to observe the flow's aftermath from a closer vantage point. Andreastuti knows the billowing pyroclastic flow is a kilometer or so away but cannot see it. “That makes me much more nervous,” she says. She has good reason to be wary. On 22 November 1994, she was with an MVO team on the north rim of Merapi's summit when, without warning, a pyroclastic flow tore down the south flank, killing 60 members of a wedding party and a few other villagers. The volcanologists were unharmed but shaken.

Around 3 p.m., after Andreastuti's crew reaches the Ngepos observation post, the seismograph is registering another pyroclastic flow barreling toward Kaliadem, bigger than the previous one. Scientists are on their cell phones, anxious to find out how bad the situation is in the east. Outside, coarse sand pellets ping and ricochet like sleet. Andreastuti and her team head northwest, to Babadan station, a mere 4.5 kilometers from the summit. The ash fall here is even heavier; eerie murkiness is punctuated by the distant plaintive voice of a muezzin calling villagers to a late afternoon prayer.

Back at headquarters that evening, the day's events are coming into focus. The first pyroclastic flow traveled more than 5 kilometers, scorching the uppermost village of Kaliadem. Just as a second MVO team had reached the scene and collected a few rock samples, they saw the second flow heading straight for them. “They had to high-tail it out of the danger zone,” says Newhall. “They got out just in time”—as did most of a search-and-rescue team. But two volunteers on the search team sought refuge in a bunker, one of several on the mountain built for such a contingency. The blast door was slightly ajar when rescuers dug down to the bunker the next day. The men had burned to death.

The mood at MVO is somber on 15 June. After 24 hours without another big pyroclastic flow, Newhall and two MVO scientists take a calculated risk. They duck back up to Kaliadem to retrieve additional samples, spending the minimum time necessary (20 minutes). “We wanted to see what's coming out right now to judge how fresh the magma might be,” Newhall says. Older magma that has wallowed near the surface loses much of its gas, the way an opened can of soda loses its fizz. If fresh magma rises too fast, its higher concentration of gases could fuel an explosive eruption.

The rocks prove well worth the gamble. An initial look shows that the hardened magma is glassier than samples of earlier flows. Newhall anticipates that analyses will reveal that the magma is indeed fresher. At first blush, the samples resemble those from the 19th century eruptions; in contrast, magma from the tamer eruptions last century was largely degassed.

Even if further evidence points to a major explosion, however, officials may have trouble persuading villagers to clear out. Most are relying on guidance from their spiritual guardian Mbah Maridjan, who is advising villagers to stay put. “The level of risk people are willing to tolerate here is remarkable,” says Newhall.

If Merapi were to regain its pre-20th century vigor, that obstinacy could be disastrous. “If you tell them, ‘Tomorrow you'll be blown to smithereens,’ that might have an effect,” Newhall says. “But we don't know that. It might be the next day. It might be never.” Merapi hasn't divulged that secret to the scientists.

2. INFLUENZA

# What Came Before 1918? Archaeovirologist Offers a First Glimpse

1. Martin Enserink

LISBON—After having resurrected the virus that caused the 1918 pandemic last year, a team of virologists is now trying to figure out which flu strains dominated the world before that global disaster.

At a meeting here last week,* Jeffery Taubenberger of the Armed Forces Institute of Pathology (AFIP) in Washington, D.C., said that RNA found in tissue samples from pneumonia patients who died in 1915 shows that the virus's hemagglutinin—an all-important coat protein—is a subtype called H3. If confirmed, “that's tremendously exciting,” says molecular biologist Ian Wilson of the Scripps Research Institute in San Diego, California. Knowing the virus's entire genetic makeup—which Taubenberger believes is possible—would shed fresh light on where the 1918 killer flu may have originated, Wilson says.

Taubenberger spent almost 10 years piecing together the genome of the virus that caused the pandemic itself, using tissue samples stored at AFIP's massive repository as well as RNA scraps isolated from the frozen body of a woman who died during the pandemic in Alaska in 1918. He and others then rebuilt the virus from scratch and studied it in mice, chicken eggs, and human cells (Science, 7 October 2005, p. 77). The 1918 virus is a subtype called H1N1, based on its hemagglutinin (H) and neuraminidase (N) proteins.

What came before 1918 is a long-running question in virology, and the answer could help to explain what some believe is a natural cycle of flu subtypes succeeding each other (see graphic). In the 1950s and 1960s, a handful of researchers tested for hemagglutinin antibodies in people born before the 1918 pandemic. They proposed that an H2 strain swept the world during a pandemic in 1889, and H3 was introduced in another pandemic in 1900. A 1999 review of those same data concluded that H3 was more likely to have struck in the 1889 pandemic but warned that “seroarchaeology is not an exact science.”

Only patient samples can yield solid answers, Taubenberger says. To find them, he teamed up with John Oxford of Queen Mary's School of Medicine at the University of London to explore a massive set of samples collected as early as 1905 and stored, along with patient records, in dusty cellars at the Royal London Hospital. Joanna Whitson, a medical student, found more than 200 suspected flu victims. So far, Taubenberger's team at AFIP has analyzed the lung tissue of only 12 of them, five of whom were confirmed to have had flu. And in four of those, sequencing of RNA snippets from the hemagglutinin gene—80 base pairs is the maximum length in these ancient samples—shows “it's absolutely an H3,” Taubenberger says.

The team plans to spend the next several years sequencing the entire viral genome. If viruses from before 1918 are completely different than the pandemic virus, that would support Taubenberger's contested theory that the pandemic virus jumped directly from an avian host into the human population, says virologist Albert Osterhaus of Erasmus University in Rotterdam, the Netherlands. “This could be the clincher,” says Oxford.

• *12th International Conference on Infectious Diseases, 15–18 June.

3. PSYCHOLOGY

# The Value of the Stick: Punishment Was a Driver of Altruism

1. Yudhijit Bhattacharjee

A hallmark of humanity is that people help other people—not just relatives and friends but even complete strangers. Such altruism, which goes beyond the mere exchange of favors and forms the scaffolding of large-scale cooperation in human societies, has long been an evolutionary mystery. On page 1767, anthropologist Joseph Henrich of Emory University in Atlanta, Georgia, and his colleagues take a crack at solving the puzzle, concluding that such helpful behavior may have arisen as a result of punishment.

Reporting on experiments they conducted in 15 different societies on five continents, the researchers argue that altruism evolved hand in hand with a willingness to punish selfish behavior. Their results lend support to models of gene-culture coevolution that propose that cultural norms such as the punishment of unfair actions drive the selection of genes favoring altruism. “It's a pathbreaking study,” says Ernst Fehr, an experimental economist at the University of Zurich in Switzerland and a proponent of gene-culture coevolution. But some evolutionary biologists, who believe that altruism toward nonrelatives evolved through repeated, mutually beneficial interactions, are unconvinced by the conclusions.

Researchers have studied the link between altruistic behavior and punishment in the past, but mainly among university students. To address whether all cultures reveal such a link, Henrich and his colleagues conducted game-playing experiments among populations such as a seminomadic community in the Kenyan savanna, inhabitants of Yasawa Island in Fiji, and farmers and wageworkers in Missouri. In one game, two players who remained anonymous to each other were given the local equivalent of 1 day's wages to divide between themselves. According to the rules, if the first player offered an amount that the second player rejected, both would walk away with nothing. The second player's decision thus provided one measure of willingness to punish.

In another game, a twist on the first one, a third person was added to the mix. If that third player felt that the first offered too little to the second, he could reduce the first player's winnings by 30%, but it would cost him a known portion of money he had been allotted. The choice of whether to ignore pure self-interest provided another measure of willingness to punish selfish acts. A final game was designed to measure altruism: Two anonymous players were given an amount to share, and one had to accept the other's offer.

The researchers found that individuals in all societies were willing to pay a price to punish unequal offers, both as the aggrieved party in the first game and as observers in the second game. Some societies were less punitive than others. And societies with a greater willingness to punish were more altruistic in the third game.

“You evolve into a more cooperative being if you grow up in a world where there are punishers,” says Henrich. His evolutionary interpretation is that “punishment may have first emerged culturally. Those who violated social norms were punished while others flourished, leading to the genetic evolution of altruistic psychologies.”

John Tooby, an evolutionary psychologist at the University of California, Santa Barbara, challenges Henrich's conclusion as a fanciful leap from games in which people remain anonymous. He notes that “in ancestral societies, people lived in small groups where everybody knew each other. In that environment, anonymous punitive interactions would have been rare to nonexistent, so there would have been no selection to adapt to such situations.” Still, Tooby agrees that the study is a significant contribution to the ongoing debate on altruism “because it tests and reports on behavioral phenomena in a carefully parallel, cross-cultural fashion.”

4. RESEARCH ETHICS

# China's Science Ministry Fires a Barrage of Measures at Misconduct

1. Gong Yidong*,
2. Hao Xin
1. Gong Yidong writes for China Features in Beijing.

BEIJING—Responding to a wave of scandals, China's Ministry of Science and Technology last week announced a slew of reforms aimed at discouraging and rooting out scientific misconduct. Although some researchers praised the initiatives, including a scheme to rate work performance and a public database of grant applications, many were skept ical they would lead to substantive change.

The Ministry of Science and Technology (MOST) outlined its proposals in a 26-point “Recommendations on Reforming Management of Science and Technology Programs,” first released in January. The scientific community paid scant attention initially, researchers say, reading it as a recycling of similarly titled older materials. Previous reform plans “were not well implemented,” admitted Vice Minister Shang Yong, who unveiled the array of more-specific measures at a press conference last week.

To limit the influence of grant managers, MOST plans to expand a database of experts it uses to review proposals and evaluate projects. Selection of reviewers will be random in the future, which MOST hopes will help reduce conflicts of interest. Another step involves setting up a “credit management system” to keep performance scores of experts who do evaluations and of institutions and individuals who undertake projects, explains Qin Yong, deputy director of the Department of Development Planning at MOST. Scores will be taken into account in making future grant decisions, he says.

The main goal, Shang says, is to increase “transparency, equity, and fairness” in program management. All nonconfidential projects administered by MOST will be handled online using a database searchable by the public. Everyone will be able to read applications, approvals, implementations, and appraisals, explains Qin. MOST says that expert reviewers' opinions will be kept confidential, however. Applications already must be submitted online, and an online evaluation system will be adopted later.

Last year, Wolf told NSF to consult with the National Academies on how to create a prize program, and its report is due in September. But the legislator says NSF “is not moving as fast as I had hoped,” so this year's House report “strongly encourages NSF to leverage private sector involvement.” Wolf says some of the $16 million he added to the president's request for NSF's education directorate, for example, could be used to leverage outside contributions. NSF Deputy Director Kathie Olsen says that NSF already uses “a number of approaches to encourage innovation” and is waiting for advice from the academies before designing any competition. She adds that NSF must avoid even the appearance of a conflict of interest from donors: For example, a company might try to offer a prize for solving a problem that would enhance its products or industry. Still, Olsen predicts that prizes “will catch the attention” of many scientists, and she guesses that NSF “should at least be able to get an announcement out in 2007.” 6. 2007 NASA BUDGET # Space Scientists Score a Modest Victory in House Spending Bill 1. Andrew Lawler After months of fretting, arguing, and lobbying, earth and space scientists got some good news last week. The House panel that funds NASA proposed adding$75 million—mostly for research grants—to the agency's science programs next year. That is less than half of what the National Research Council (NRC) urged in a May report, but it demonstrates that researchers have the political muscle to battle the Administration's campaign to replace the space shuttle and return humans to the moon at the expense of several scientific projects.

Overall, the House appropriations subcommittee chopped $83 million from NASA's request for$16.8 billion, giving it only $86 million more than current levels. But lawmakers proved sympathetic to the science community. The spending bill includes$10 million to revive the Terrestrial Planet Finder and $15 million to restart planning for a mission to Jupiter's moon Europa, both of which NASA wants to postpone indefinitely to save money. Legislators added$50 million to a grants program that NASA proposed holding flat after this year, heeding the pleas of scientists for more money to analyze data from instruments yet to be launched. But the panel declined to restore funding for a host of small missions, in effect delaying them indefinitely.

“We're pleased they fixed at least one of our problems,” says Lennard Fisk. An atmospheric chemist at the University of Michigan, Ann Arbor, Fisk chaired the NRC panel, which called for an additional $50 million for the research grants and$110 million across several small programs. Fisk also praised the low number of earmarks, which in recent years have eaten up an increasing share of science funding.

To offset the additions to science and a $100 million boost to the request for aeronautics research, the panel cut$151 million from President George W. Bush's $4 billion exploration effort, mostly in advanced technology work. But one NASA official said the agency isn't complaining, because it received nearly full funding for the space shuttle, the space station, and the shuttle-replacement program. The Senate is likely to add both earmarks and research funds to its version of the bill later this year. Toward that end, senators Barbara Mikulski (D-MD), ranking minority member of the Senate panel, and Kay Bailey Hutchison (R-TX), who chairs the NASA authorizing panel, hope to meet soon with Vice President Dick Cheney to discuss an emergency funding bill to cover a long-term shortfall in shuttle, exploration, and science spending. NASA, meanwhile, seems on the verge of reversing its plan to cancel the Stratospheric Observatory for Infrared Astronomy (SOFIA) (Science, 17 March, p. 1540). The same day that the House panel proposed its funding plan, NASA said SOFIA faces no further technical hurdles. But the search for the money to complete and launch SOFIA will spark yet another battle over the allocation of NASA's scarce research funds. 7. EVOLUTION # Spider Genes and Fossils Spin Tales of the Original Worldwide Web 1. Erik Stokstad Building an orb web is no simple affair. Spiders suspend the silky equivalent of guy wires, attach radial spokes, and then weave in a sticky spiral to snare prey. Two groups of spiders—deinopoids and araneoids—make such webs. Their use of different kinds of adhesives for the “capture spiral” once made biologists think that the two spider lineages had evolved orb weaving independently. But the discovery of similar construction techniques made a single origin of orb webs seem more likely, and a new study of silk genetics on page 1762 strengthens the case. “It's really cool to see this matched by the genetic evidence,” says Gustavo Hormiga, an arachnologist at George Washington University in Washington, D.C., about a study led by Jessica Garb, a postdoc at the University of California, Riverside (UCR). Two other new papers describe fossils of spiders and their webs that further emphasize the antiquity of orb webs. Deinopoids follow the more ancient silk recipe. They swathe their capture spirals in dry silk. First, a spider oozes fibrils just tens of nanometers in diameter from thousands of spigots on its abdomen. Then the spider combs the threads like cotton candy onto a support line that makes up the spiral. When a fly or other prey brushes up against the fibrils, electrostatic forces pin it to the web. Araneoids simplified the process. Using a pair of glands that deinopoids lack, they simply dab a viscous glue onto the support line. That approach takes about one-tenth the effort of making dry silk, and the adhesive is 13 times stickier per unit volume. The web is also less visible to insects, because the silk doesn't reflect ultraviolet light. All these advantages may help explain why araneoids are 10 times more diverse than the deinopoids. Scientists have extensively studied the genes and proteins that make spider silk stretchy and strong (Science, 25 February 2000, p. 1378), but most of the work has focused on araneoids. Garb decided to take the web less traveled by. Working with Cheryl Hayashi of UCR and others, she studied complementary DNA from silk glands of two kinds of deinopoids, Deinopis spinosa and Uloborus diversus. The team found that the deinopoids had genes (known as Flag, MaSp1, and MaSp2) quite similar to those that araneoids use to make silk for the capture spiral and radial spokes—additional evidence for a single origin of orb webs. That's not a surprise to spider biologists, but it's pleasant confirmation that their previous observations “are as valid as we thought they were,” says Brent Opell of Virginia Polytechnic Institute and State University in Blacksburg. Two new fossils described this week underscore the long-lived success of orb webs. On page 1761, a team led by David Grimaldi of the American Museum of Natural History in New York City reports the oldest example of spider silk entrapping prey. In a chunk of 110-million-year-old amber from Spain, they found a fly and a mite ensnared in strands of gluey spider silk, possibly from an orb web. Meanwhile, in the 14 June online issue of Biology Letters, David Penney of the University of Manchester, U.K., and Vicente Ortuño of the Universidad de Alcalá, Madrid, describe the oldest true orb-weaving spider: an araneoid found in 115-million-year-old Spanish amber from a different site. The 2-millimeter-long spider, which they name Mesozygiella dunlopi, is remarkably similar to a living spider—showing that the basic, and successful, body plan appeared long ago. 8. SPECIES CONSERVATION # A 'Forever' Seed Bank Takes Root in the Arctic 1. Daniel Charles* 1. Daniel Charles is a freelance writer in Washington, D.C. LONGYEARBYEN, NORWAY—The prime ministers of five Nordic countries gathered here on the arctic archipelago of Svalbard last week to mark the beginning of a unique bunker: an underground vault that will hold up to 3 million seeds. Launched with$3 million from Norway, the project seeks to preserve the DNA of agricultural crops—the most complete such collection in the world by far. “It will contribute to ensuring our food security [and] protect our cultural heritage,” says Norwegian Prime Minister Jens Stoltenberg.

The seed bank is intended as a backup for existing collections, which have proven to be vulnerable. Collections of seeds in Afghanistan and Iraq, for example, were destroyed by war, and some of the oldest seed banks in the world, including one in Russia and a collection of apple varieties in Kazakhstan, are deteriorating.

The Svalbard vault, carved into the side of a rocky, snow-streaked mountain near the town of Longyearbyen, will be built to withstand everything from nuclear war and bomb threats to global climate change. Its chief advantage is its location. Longyearbyen (population 1900) sits just 1120 km from the North Pole. During the winter, residents endure complete darkness for almost 4 months. Thanks to the Gulf Stream, temperatures in summer usually rise a few degrees above freezing, but under the surface, the earth remains permanently frozen, easing the task of keeping seeds refrigerated at −18°C. Even if equipment fails, it would be many weeks or even months before the vault reached −3°C, the temperature of the surrounding sandstone.

The vault eventually will hold seeds representing almost the entire gene pool of the world's agricultural crops. Cary Fowler, executive director of the Global Crop Diversity Trust, calls the genetic diversity in existing seed collections “the most valuable natural resource in the world.” Most of those varieties vanished from fields over the past century as farmers adopted the products of modern breeding programs. So when plant breeders are looking for genetic resistance to emerging plant diseases, or for genes that may improve yields further, they often are forced to turn to the gene banks.

But there will be a few gaping holes in the collection: China and a few African countries refused to include soybeans and peanuts in a recent international treaty that protects the free exchange of seeds among plant breeders. Those nations aren't likely to contribute copies of their important collections of those crops.

The first seeds to arrive at Longyearbyen will come from international centers such as the International Rice Research Institute in the Philippines or the International Center for Agricultural Research in the Dry Areas, located in Syria. After that, gene banks run by national governments will contribute additional samples. “We will limit this to unique seeds and try to avoid duplication,” says Grethe Evjen of Norway's ministry of agriculture and food. But that may be difficult because many collections aren't well cataloged. Fowler's group plans to raise $100,000 a year to operate the seed bank. Some scientists believe that preserving and deepening knowledge of these collections is as important as preserving the seeds themselves. “If the people who know about the collections are gone, I would say that 75% of the utility will be gone,” said Major Goodman, a specialist on maize at North Carolina State University in Raleigh. Of the half-dozen top maize specialists worldwide, he said, almost all are nearing retirement: “For maize, we need at least eight young people trained in this area.” The prospects for so many positions appear bleak. But the Svalbard vault may help. “It's extremely good publicity,” says Geoffrey Hawtin, former director of the International Plant Genetic Resources Institute in Rome. “It captures the public's imagination.” 9. ARCHAEOLOGY # First Jewelry? Old Shell Beads Suggest Early Use of Symbols 1. Michael Balter A high school ring, a string of pearls on Oscar night—how we decorate our bodies says a lot about who we are. Archaeologists think such symbolic communication marks the mental leap that made art and language possible. But when did it begin? On page 1785, researchers claim that three grape-sized shells from the Levant and North Africa were worn as beads 100,000 or more years ago. If true, this would push back the earliest evidence for symbolism by at least 25,000 years. “This is an important and exciting contribution,” says archaeologist Christopher Henshilwood of the University of Bergen in Norway. Two years ago, Henshilwood reported finding 75,000-year-old marine shell beads at Blombos Cave in South Africa, then the earliest claimed ornaments (Science, 16 April 2004, p. 369). Yet archaeologists who were skeptical about Blombos also question the new claim. “The evidence seems weak to me,” says Richard Klein of Stanford University in Palo Alto, California, who has long argued that the symbolic explosion took place in Europe and Africa about 40,000 years ago. The team, led by archaeologists Marian Vanhaeren of University College London and Francesco d'Errico of the research agency CNRS in Talence, France, found the beads in museum drawers. Two came from 1930s excavations at the Skhul rock shelter in Israel, where 10 burials of early Homo sapiens had been found. The other one came from the open-air site of Oued Djebbana in Algeria, excavated during the 1940s. Vanhaeren and d'Errico retrieved the shells and examined them for signs of use as ornaments. All three suspected beads are shells of the marine snail Nassarius gibbosulus. Each has a distinctive type of indented perforation that turns up only rarely in reference collections. The team concluded that humans either made the holes or picked out perforated shells to string together as ornaments. Recent dating of the Skhul burials has shown that they are 100,000 to 135,000 years old. (Oued Djebbana is poorly dated but is at least 35,000 years old and possibly much more.) To be sure that the Skhul shells came from the burial layer, Vanhaeren and d'Errico's team used scanning electron microscopy, x-ray diffraction, and chemical analysis to examine sediments stuck to one of the shells. The sediments matched those from the burial layer, suggesting that early modern humans did indeed create shell beads 100,000 or more years ago. The team's findings are “particularly compelling evidence for symbolic use of the shells as beads,” says anthropologist Alison Brooks of George Washington University in Washington, D.C. Such personal ornaments, Henshilwood adds, are “expressions of modern cognitive abilities” and also indirect evidence “for the acquisition of articulate oral language.” And because neither Skhul nor Oued Djebbana was very close to the sea, says Steven Kuhn, an archaeologist at the University of Arizona in Tucson, humans must have carried the small shells—which have almost no food value—to the sites for symbolic purposes. Nevertheless, Kuhn cautions that the Skhul shells could have come from a younger stratigraphic layer and picked up older sediment after they “filtered down” into lower layers. And Klein argues that even if they are beads, such artifacts are so rare at sites older than 40,000 years that their interpretation as full-blown symbolic behavior remains “debatable.” Yet some researchers think more evidence will turn up—and not just in museum drawers. Says Henshilwood: “I believe this is the tip of the iceberg.” 10. SEISMOLOGY # The Strain Builds in Southern California 1. Richard A. Kerr A fatalist would just observe that earthquakes happen, especially in California, and let it go at that. But seismologists and emergency-response planners would like to know where and when the next great quake—the Big One—is going to strike in California. This week in Nature, geophysicist Yuri Fialko of the Scripps Institution of Oceanography in San Diego, California, reports that the southernmost San Andreas fault is indeed building strain at a dangerous rate. If, as seems likely, strain has been accumulating there at the same clip since the last big strain-releasing quake, the next one will probably come within a few decades, according to one forecast. The 4 million people of Riverside and San Bernardino—and even distant Angelenos—should take note. “There's a lot of concern about this southernmost segment of the San Andreas,” says paleoseismologist Ray J. Weldon of the University of Oregon, Eugene. It's now looking like “the most dangerous” fault in California. The southernmost San Andreas has long been suspect. In the last 2 decades, paleoseismologists found signs of the last quake to rupture the 200 kilometers of fault running from San Bernardino and Riverside to beyond the Salton Sea. That quake struck more than 300 years ago. And the strain building on the fault was increasingly deforming the surface, geodesists found using precise distance-measuring instruments on the ground as well as the Global Positioning System. So the southernmost San Andreas appeared to be working up to its next big quake, probably something like a magnitude 7.5. But southern California is a tectonic mess. The North American and Pacific plates don't simply jerk past each other along the San Andreas. Instead, fault slip—and earthquakes—occur on three or more adjacent faults, including the San Andreas and the San Jacinto fault, a side fault that joins the San Andreas at San Bernardino. Some plate motion might even occur without generating earthquakes. To sort out how much strain is actually building on each fault, Fialko analyzed radar data that Europe's Earth Remote Sensing satellites ERS-1 and ERS-2 had gathered between 1992 and 2000. By combining sequential satellite passes using the interferometric synthetic aperture radar (InSAR) technique, Fialko found strain accumulating on both the San Andreas and San Jacinto but not on other subsidiary faults. “He's able to put a very solid number on the slip rate of the San Andreas,” says geodesist Roland Burgmann of the University of California, Berkeley. “There's just no way around the result.” About 55% of the motion between the two plates occurs on the San Andreas, according to Fialko's results. That's enough to confirm researchers' concerns about the next big one. Weldon and colleagues have estimated a 70% probability that the southernmost San Andreas will rupture within the next 30 years. With the new InSAR data, says Weldon, “I think people are starting to believe it.” People in San Bernardino and Riverside would be within the zone of strongest shaking along the fault, and geologic crustal structure would focus seismic waves from a northward-propagating rupture into downtown Los Angeles. About 45% of plate motion is on the San Jacinto fault. That's more bad news for the San Bernardino-Riverside area. If true, the San Jacinto will have larger quakes than previously thought, says Weldon. Magnitude-7 quakes on the San Jacinto “could be as bad as a 7.5 on the San Andreas,” he says. On the bright side, having all the plate motion on just the two faults would mean that no significant motion would be left for faults such as the Elsinore, which reach into Los Angeles itself. 11. EUROPEAN SCIENCE # E.U. Parliament Approves Funding for Human ES Cells 1. Gretchen Vogel Scientists working with human embryonic stem (hES) cells in Europe breathed a sigh of relief last week as a final threat to Europe-wide funding of the work was lifted. On 15 June, the European Parliament voted down two amendments that would have restricted funding for hES cell research under the €50 billion ($63 billion) Framework 7 program, which will fund research in the E.U. from 2007 through 2013.

Among hundreds of suggested amendments to the Framework 7 proposal, the Parliament gave a broad endorsement to plans for the European Research Council, a new funding agency that would support top individual scientists across Europe, and made tweaks to the amount of money allocated to renewable energy and research by small businesses.

But the embryo issue was the most contentious. Many scientists hope hES cells will help them understand human development and treat disease in new ways, but the work is controversial because the cells are derived from week-old human embryos. The 25 E.U. member countries have different laws governing embryo research, ranging from very permissive to outright bans; some opposed spending E.U. money on it.

Under a compromise worked out in 2002, the current Framework 6 program can fund hES cell research if the work receives an ethical endorsement from the host country, an E.U.-level ethics committee, and a panel with representatives from all member countries. Scientists had lobbied to retain this policy in the face of two amendments that would have either blocked or restricted hES cell research. Both those amendments failed, however, and in a 284-249 vote, the Parliament approved a measure that continues the current policy.

Embryo research is a tiny but key slice of the Framework program, says Elena Cattaneo of the University of Milan in Italy. Cattaneo's lab received €10,000 to work on hES cells through EuroStemCell, a €12 million project funded by Framework 6. Although such work is not prohibited in Italy, she says, funding is unavailable from national sources.

Parliamentary and commission representatives will iron out their differences in meetings in the coming month. The revised Framework 7 program then needs the final endorsement of the Parliament and the research ministers of member countries.

12. U.S. BIOETHICS

# House Panel Finds Fault With How NIH Handles Tissue Samples

1. Jocelyn Kaiser

A congressional finding that a drug company paid a National Institutes of Health (NIH) scientist for spinal fluid samples has raised a larger question: What happens to NIH's archived patient samples? NIH's efforts to improve practices within its intramural program come as U.S. medical centers are trying to tighten controls over such materials.

At a 2-day hearing last week, Joe Barton (R-TX), chair of the House Energy and Commerce Committee, complained about the “lack of a centralized database [for patient samples] and a lack of oversight at NIH that could, and probably does, leave NIH laborator[ies] vulnerable to the risks of theft and abuse.” NIH officials testified they have already begun to improve their procedures.

But outside scientists agree with NIH that the agency needs time to organize its millions of stored specimens. “People have their samples everywhere,” with details recorded on everything from paper notepads to computers, says Mark Sobel, a former NIH researcher who is now executive officer of the American Society for Investigative Pathology. Creating a central registry of NIH's holdings, he predicts, “is going to be a massive undertaking.”

Barton's ethics investigation is an extension of an earlier one questioning large payments from drug companies to senior NIH scientists. That led NIH to ban industry consulting by its intramural scientists last August (Science, 2 September 2005, p. 1469). Last week's hearing focused on Alzheimer's disease researcher Trey Sunderland of the National Institute of Mental Health (NIMH) and his dealings with drug giant Pfizer.

The committee pursued a complaint from Susan Molchan, a former clinical researcher in Sunderland's lab, that Sunderland wouldn't provide her with some of her old spinal fluid samples. Staffers eventually learned that Sunderland had sent Pfizer about 3200 spinal fluid samples and 388 plasma samples he and others had collected since the early 1980s, including some from Molchan, along with clinical data, from Alzheimer's patients and controls. The company used them to study so-called biomarkers, proteins that might serve as indicators for the neurodegenerative disease.

Pfizer had signed a Material Transfer Agreement with NIMH for the samples in April 1998. Around the same time, Sunderland signed a consulting agreement with Pfizer that eventually paid him $285,000. A 26-page bipartisan report released last week by the Commerce Committee's oversight and investigations subcommittee found “reasonable grounds to believe” that Pfizer made the payments in exchange for the samples. Neither this agreement nor others with Pfizer, for which Sunderland was paid more than$300,000 over several years, were reported to NIH.

At the hearing, NIH officials said the transfer and consulting agreements would not have been approved because they improperly mixed official duties with consulting. “You could have both collaboration and consulting [but not] with the same agent,” said NIMH Director Thomas Insel. Insel said Sunderland instead should have organized a cooperative agreement with the company for which he would not have been paid.

Sunderland and a co-worker, Karen Putnam, invoked their constitutional right to decline to answer questions before the committee. Sunderland has said that his staff simply failed to complete the proper paperwork, and his attorney Robert Muse says that “there is no truth to the allegation that Dr. Sunderland received a penny from Pfizer for the samples.” NIH investigators earlier found that Sunderland had committed serious misconduct, and Insel suggested to the U.S. Public Health Service Commissioned Corps that he be terminated. The corps has put his retirement on hold, however, and the Department of Health and Human Services Inspector General's office and the Department of Justice are still investigating.

The committee's report also questions whether Sunderland had obtained proper informed consent from some patients for the Pfizer study. NIH officials told the subcommittee that they have tightened rules on the sharing of human tissues, including adding a requirement that investigators describe future plans for samples to an Institutional Review Board (IRB). In the mid-1990s, the policy was “very general,” Insel said.

Indeed, a decade ago, researchers themselves often decided the fate of leftover samples, says bioethicist Mark Rothstein of the University of Louisville in Kentucky. Since bioethics council and other U.S. and international advisory bodies have called for better controls on the use of stored human tissue (Science, 18 December 1998, p. 2165). Reviews of old collections have revealed that informed consent forms are often missing, leaving IRBs to decide whether samples can be used, Rothstein says: “It's been a revelation.”

But NIH officials say they need more time to figure out whether a central database of tissue specimens would make sense for the intramural program. The agency is looking at combining a new campuswide database of clinical trials with sample barcoding systems, says NIH Deputy Director for Intramural Research Michael Gottesman. And although extramural researchers have also traditionally tracked their samples individually, NIH's largest institute, the National Cancer Institute, is encouraging cancer centers to tally their tumor specimens in databases so sharing will be easier.

Insel warned that moving toward a central system too quickly could add “speed bumps” to the scientific process. Legislators haven't said if they plan to require a central database.

13. ANIMAL COGNITION

# Social Animals Prove Their Smarts

1. Elizabeth Pennisi

A new generation of experiments reveals that group-living animals have a surprising degree of intelligence

A Fox observed a Crow in a tree with a piece of cheese in her mouth. Hungry for the cheese, he thought up a ruse to get it. He said, “What a noble bird I see above me! Her beauty is without equal. If only her voice is as sweet as her looks are fair …”

The Crow was greatly flattered, and to show the Fox that she could sing, she opened her mouth and gave a loud caw. Down came the cheese. The Fox, snatching it up, said, “You have a voice, madam, I see: What you want is wits.”

—Retelling of a fable by Aesop

In Aesop's time, it was common to endow animals with qualities of the human mind. In addition to the flattering fox, Aesop told of a deceitful eagle that lured a turtle to its death and a compassionate lion that exchanged favors with a shepherd. But although folktales often feature scheming or generous animals, scientists have spent most of the past few centuries thinking of other species as “dumb,” or at least driven by innate behaviors. Even when biologists, anthropologists, and psychologists finally began to appreciate the complexity of animal cognition in the 1950s, they tended to focus on the mental advantages that still separated humans from the rest of the animal kingdom.

Even 10 years ago, most researchers considered the intellectual chasm between humans and animals too broad for even primates to begin to bridge. A few claimed that animals have advanced cognitive skills, but early studies were chiefly anecdotal and convinced few hard-core experimental biologists, says Michael Tomasello, a developmental psychologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “From a scientific point of view, most of the evidence [for higher cognition] was not very good,” he says.

In the past decade, however, the field of animal cognition has taken off, galvanized in part by a once-obscure idea that the development of social skills drove the evolution of general intelligence (see sidebar). The thinking is that the need to remember and track peers sharpened social animals' ability to do other useful cognitive tasks, such as remembering where and when particular fruit trees were ripe for the picking, or learning tool use from a particularly creative peer. From this perspective, abilities such as remembering the identity of dominant individuals are crucial steppingstones to the most advanced cognitive abilities, such as learning how to interact with those dominants for personal gain—something scientists assumed only humans could do.

Of course, humans are masters of social intelligence. We judge friend from foe and head honcho from underling by the raising of an eyebrow. We scheme, deceive, and sometimes help others with no gain to ourselves. But it turns out that other animals can do these things too, at least to some degree. Researchers using rigorous tests of such abilities in animals are finding numerous examples. Crows deceive each other, as do apes; hyenas keep track of social hierarchies. There are enough parallels that now “everyone is interested in discovering the similarities between animals and humans,” says Bennett Galef, an emeritus animal behaviorist at McMaster University in Hamilton, Canada.

Together, the new studies, particularly those of apes and birds, are providing provocative evidence that perhaps humans aren't as special as we might like to think, says Brian Hare, a biological anthropologist also at the Max Planck Institute for Evolutionary Anthropology. What was once considered a sharp line separating humans from all other animals is becoming a blurry gray area, with various animals possessing certain parts of the set of skills that we consider advanced cognition.

In large part, that's because we're not the only species that has evolved to cope with the demands of living in groups, says Nicola Clayton, who studies animal cognition at the University of Cambridge, U.K. People in villages, chimps in troops, ravens in flocks, and hyenas in packs all need to be able to size each other up and modify their behaviors as needed.

Not all researchers are impressed with animals' newly demonstrated social ingenuity, and there is disagreement about its implications. All the same, says Marc Hauser of Harvard University, for cognitive scientists the research questions have changed, from what sets humans apart, to what animals reveal about the building blocks of higher cognition.

## Understanding understanding

Throughout history, researchers have swayed back and forth on the question of animal intelligence. In the 1600s, nonhuman animals were considered little more than breathing machines. But after Darwin implied that differences between humans and other species were a matter of degree, dozens of examples of “smart” animals came to light, only to be subsequently debunked. During the 19th and early 20th centuries, the prevailing idea became that most animals, primates included, didn't reason but instead had sets of rules that dictated their behavior. And animal-cognition researchers avoided inferring states of mind from an animal's behavior. They took their cues from 19th century psychologist C. Lloyd Morgan, who argued that complex behaviors don't necessarily require complex thought, and that researchers should look for simple, mechanistic explanations for even the most complex animal behaviors.

But starting in the late 1970s, some researchers went against the grain. In 1976, psychologist Nicholas Humphrey of the London School of Economics stirred the pot by suggesting that getting along with others required more brainpower than other aspects of daily life, and that social animals might have humanlike smarts. “It was very much at odds with what everyone was thinking at the time,” Humphrey recalls.

Two years later, psychologists David Premack and Guy Woodruff of the University of Pennsylvania proposed that chimpanzees might be able to think about what they are doing and to understand what others are thinking, an ability they called a “theory of mind.” Even as children, humans can read each other's minds at least to some degree. Maybe chimps could as well, if we could only find a way to communicate with the apes, Premack and Woodruff proposed. And in the late 1980s, Andrew Whiten, an evolutionary psychologist at the University of St. Andrews in Fife, U.K., and his colleagues suggested that the relatively big brains of humans and other primates evolved not to see, smell, or fight better but to recognize and deal with social dilemmas.

But “it took a while for people to start thinking about these ideas,” says Clayton. Today, psychologists recognize “theory of mind” as a critical cognitive skill, underlying teaching, deception, and perhaps even language (Science, 16 May 2003, p. 1079). It's also seen as a steppingstone to consciousness, or thinking about one's own thoughts—often considered the ultimate in higher cognition (Science, 25 June 1999, p. 2073).

Yet scientists disagree on exactly what theory of mind is, and the literature is filled with conflicting reports about its existence in animals. As recently as 6 years ago, Hauser argued that chimps didn't have even the basics of a theory of mind. Today, “the field has been completely turned upside down,” says Hauser. “The provocative question is not do they have a theory of mind; it is thinking about the components that are going into theory of mind.”

Corporate meetings, playground games, and bargain shopping all require complex negotiation skills and a keen sense of who one's allies are. It makes sense that apes, our closest kin, should be political as well, but it has taken decades for scientists to come to grips with the idea that apes have street smarts akin to ours. Beginning in the 1960s, field researchers such as Jane Goodall were reporting sophisticated politics among chimps, for example, but controlled experimental evidence was rare.

Apes rarely did well on self-awareness, memory, gaze-following, gesture, spatial learning, and other tests at which even young children excel. For example, children will follow another person's gaze, showing that they are aware that the tester is in fact looking at something. But chimps confronted with humans with or without blindfolds on their heads didn't discriminate among who could see—and therefore deliver a reward—and who couldn't.

Then 6 years ago, Hare and his colleagues showed that under the right circumstances, chimps could pass some of these tests with flying colors. The secret was that chimps are exquisitely tuned in to their competition, particularly when food is involved, and will do everything they can to get a treat.

In one experiment published in 2001, Hare, Tomasello, and their colleagues paired a dominant chimp with a subordinate and manipulated the two apes' view and access to food. If both could see the food, the subordinate deferred. But if the dominant chimp couldn't see the treat, the subordinate quickly snapped it up.

The experiment, coupled with a related but simpler one published a year earlier, was revolutionary. “There was a big change in perspective,” says Clayton, and a flurry of more ecologically appropriate experiments—geared to what motivates chimps in the wild—followed. For example, in a new study in Cognition, Hare and his colleagues designed another competition over food. They had chimps go head-to-head against a human who pulled food out of reach as a chimp went to grab it. If the chimps were given the option, they sneaked up behind a barrier to get to the food instead of approaching it directly. Thus, the chimps demonstrated not only that they knew what the human could see but also that they knew how to manipulate the situation to stay out of sight. Other studies have shown that chimps can recognize when a human is imitating them.

They can also sense the motives of others. A study a few months ago showed that chimps kept track of partners who best collaborated in retrieving inaccessible food and chose that same partner again in the next trial (Science, 3 March 2006, p. 1297). New experimental designs are helping to demonstrate chimp smarts outside the social realm, too: Studies show that they can reason about the movement of things they cannot directly see and plan for the future by taking account of past experiences.

In parallel, other researchers are demonstrating that social primates are smart enough to help their cause through teaching and learning. Chimps apparently learn tool use from one another, and communities in different regions of Africa develop what some researchers consider cultural differences in tool use. The idea is still controversial, but field and, more recently, lab work are strengthening the case.

Last year, Whiten and his colleagues demonstrated “social learning” of traditions in two groups of captive chimpanzees. The researchers trained one female from each group either to pull or to lift a stick tool to retrieve a reward. After watching the female for just 20 minutes a day, each group learned its respective technique within a week. Not only were the chimps able to copy the lifting or the pulling, but lifters also almost never tried to pull or vice versa, suggesting a strong tendency to conform to the local norms, Whiten suggests.

Taken together, this work shows striking parallels with human abilities, says Hare. But do chimps have a theory of mind? They lack the most advanced skill identified by Woodruff and Premack: the ability to realize that another individual is thinking something wrong, or that it has a false belief, points out cognitive scientist Daniel Povinelli of the University of Louisiana in Lafayette. In his view, to have a theory of mind, a species must pass the false-belief test. And so far, chimps fail it. “People who [keep] insisting that ‘It's got to be there, at least a little bit,’ in dogs, cats, chimpanzees, my cousin Ned's horse are really missing the point,” Povinelli says.

But Hare argues that theory of mind is “a whole suite of abilities.” The new results indicating that chimps can judge what others are thinking, manipulate others through deception, and so on “are shooting down the all-or-none hypothesis about theory of mind,” he says.

He adds that the false-belief test is so challenging that it foils children up to about age 4. In one test, for example, a child and a companion watch a tester put candy in a box. When the companion leaves, the candy is moved into a bucket. Because the child doesn't yet have a sense of false belief, she thinks the companion will know to look in the bucket, whereas an adult realizes that the companion still thinks the candy is in the box.

Hare argues that experimenters simply haven't found a good way to figure out where a chimp expects the companion to look for the treat, and that therefore we don't know yet whether chimps pass or fail this test. “We have not been able to come up with a convincing experiment with nonhumans,” he says.

## Picking bird brains

So far there's no evidence—and no good tests—of understanding false belief in birds. But contra the opinion of the fox in Aesop's tale, Clayton and her colleagues have found that crows and their relatives, including ravens and scrub-jays, have social intelligence on par with primates, apparently deceiving others in order to win more food. In Clayton's studies, she takes advantage of the natural tendency of many birds to stash surplus food in anticipation of lean times, and for other birds to steal those caches.

She and her husband Nathan Emery have recreated this behavior in her lab at the University of Cambridge, providing captive birds with sand-filled trays in which to bury wax worms. Sometimes the duo switches the food after it's been hidden; in other cases, they allow another bird to witness the burial. “They are putting birds in different situations and showing that the birds do all sorts of flexible things,” says Hare.

Using this approach, Clayton and her Cambridge colleague Anthony Dickinson have shown that western scrub-jays remember what they have buried, and when and where they buried it, a phenomenon called mental time travel. They retrieve perishable food before it rots, for example, while waiting longer to retrieve nonperishable items. Many animals can remember where food has been placed, but rarely have researchers demonstrated that an animal can keep track of when an event occurred and use past events to figure out what to do in the future. This ability was demonstrated in bonobos and orangutans only recently, in an experiment published online in Science last month (16 June, p. 1662). The study showed that these primates could select the proper tool for a task even though they wouldn't need it until the next day. And in this week's issue of Current Biology, other researchers demonstrated that mangabeys, a primate found in Uganda, will take note of unripe fruit and come back to pick it after a few sunny days.

For birds, anticipating the future enables them to realize when they must take evasive action to protect stashed food. Working with Joanna Dally, then a graduate student, and Emery, Clayton showed in another experiment that western scrub-jays that see a potential thief will hide food far away from the other bird and sometimes move their supplies several times. In other cases, they wait to stash food until the onlooker is distracted. The jays take none of these precautions if no other birds are in sight. “There's flexibility at multiple levels,” says Clayton.

Furthermore, birds who have been thieves themselves are more likely to take these evasive actions than birds who have not been so nefarious. The jays' behavior implies that they are aware of the onlooker's intentions and are using their past experience to predict the future actions of the potential thief, says Clayton.

In addition, like apes, the jays track the social status of their competitors and change their behavior accordingly. In the lab, scrub-jays try hard to hide food from dominants but not from breeding partners, whose pilfering is tolerated, Clayton's group reported. All this hints that jays do have elements of a theory of mind, says Clayton.

Lab work on ravens supports this idea. In most cases, a raven poised to grab another raven's stashed food doesn't hesitate to act when bystanders might beat them to it, Thomas Bugnyar and Bernd Heinrich of the University of Vermont in Burlington reported in 2005. But if the stash belongs to a dominant member of the flock, the thief will briefly search elsewhere, as if to allay suspicion. Such actions seem intentional and suggest that the thieves understand what other birds are seeing, says Bugnyar. “There's no question that birds are more intelligent than anyone thought they would be,” Tomasello says.

But researchers still don't agree on how to interpret these results. Cognitive ethologist Marc Beckoff of the University of Colorado, Boulder, sees little difference in social prowess between humans and other species, and he suggests that animals should be treated more like humans.

Other researchers still draw a line separating the minds of humans and animals, even other social species. The new experiments highlight how “various species have remarkable cognitive skills for the problems they must solve,” but they stop short of showing a theory of mind or other advanced cognitive skills, says Povinelli. Humans, by virtue of having language, have a fundamentally novel cognitive system, he points out. Tomasello agrees, noting that humans excel at many skills: They are better teachers, for example.

Furthermore, what looks like humanlike cognition may not be. Dogs, for example, seem to know what their owners are thinking. But “they are not reading people's minds but our behavior,” cautions Clive Wynne, a psychologist at the University of Florida, Gainesville. For example, those ravens avoiding the wrath of dominant birds could be picking up on subtle behavioral cues that humans can't read, he says.

To resolve whether external cues or internal decision-making underlie seemingly intelligent behavior, researchers need to expand their studies to include more species, Wynne says. “We're only studying a tiny, tiny fraction of animals,” he says. “We really don't know what's out there.”

Those studies are beginning, and by looking across the animal kingdom, researchers are gleaning the conditions that predispose a species toward social intelligence. For example, Kay Holekamp, an ethologist at Michigan State University in East Lansing, has observed hyenas for 18 years and concludes that these scavengers can recognize not just their own status relative to the pack leader but also the status relationships of other pack members. Other researchers are trying to measure social intelligence, albeit often in indirect ways, in ungulates, elephants, and dolphins. And in this week's issue of Current Biology, researchers demonstrated that fringe-lipped bats learn to listen for unfamiliar prey from fellow bats.

All these studies suffer from the same limitation, however. Researchers still can't read the minds of their subjects, warns behavioral ecologist Anne Engh of the University of Pennsylvania: “Until we can come up with creative methods of testing, we won't know whether complex behaviors are the result of animals actually knowing what they are doing or whether they are able to do complex things using cognitive short cuts.”

Galef is particularly skeptical of researchers who have concluded that chimps respond to peer pressure, that wolves and capuchin monkeys have a sense of fairness, or that jackdaws are the avian equivalent of the Good Samaritan. “It's gotten a little out of hand,” he complains. And not one species has yet passed the falsebelief test, he points out.

But does that matter? “It's not clear to me that you need [a complete] theory of mind to be very skilled socially,” says Hare. And for much of the animal kingdom, those skills are good enough. Just ask Aesop.

14. ANIMAL COGNITION

# Man's Best Friend(s) Reveal the Possible Roots of Social Intelligence

1. Elizabeth Pennisi

When a chimp sneaks a banana behind another chimp's back, it's showing social intelligence. So is the crow that buries worms behind a bush to prevent bystanders from spotting the location of its stash. Recent controlled experiments show that some social animals have evolved the flexibility and intelligence to deceive and benefit from others and even predict what their peers may do (see main text).

But why did these and related abilities evolve? In the 1970s, Nicholas Humphrey, now of the London School of Economics, proposed that natural selection favored the ability to distinguish anger from acceptance and to respond to changes in the moods of one's companions. Individuals with these kinds of social skills had advantages in gleaning food and mates—and avoiding violence, he suggested. But such evolutionary scenarios are hard to test. Now Brian Hare and Michael Tomasello of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and their colleagues are gleaning some clues from studies of domestic dogs and their wild cousins, wolves and foxes.

Even as puppies, canines are adept at taking cues from their owners—more adept than chimps, who are rarely able to follow a human's eyes or hands to hidden food. That indicates a genetic component to this skill. For decades, anthropologists have hypothesized that this behavior began when dogs and humans were able to tolerate each others' company without aggression. Togetherness fostered dogs' social skills, helping ensure their access to food and other resources without having to resort to violence. Dogs better at reading human minds were favored by selection, leading to a cycle of interaction and cooperation.

That hypothesis is backed up by Hare's studies of foxes bred for the past 45 years to be comfortable with humans. These foxes understand human gestures—for example, when a human points to food—but untamed foxes don't, even after extensive efforts to train them, Hare and his colleagues reported in 2005. Studies done in 2002 and 2003 reveal “the exact same difference between dogs and wolves,” says Hare. Selecting foxes for “togetherness” with humans also facilitated the evolution of the ability to understand their two-legged caretakers.

A similar cycle of tolerance leading to increased communication may have spurred the evolution of social intelligence within a species, says Hare. As social tolerance increased, group members could get close enough to an innovative, tool-using peer to imitate the behavior. Selection could also favor even more congenial relationships, say for cooperative food gathering or childcare, to the benefit of all involved.

And the limits of social tolerance may partly explain differences in intelligence among species, says Tomasello. For example, chimps have competitive strategies down cold and can be quite sneaky. But they don't cooperate very effectively, at least not intentionally; they would have come to a bad end in Aesop's fable about the lion and the shepherd who traded favors. In contrast, although humans too are competitive, we also possess the capacity for more empathetic social skills. “We lie, but we can also cooperate and coordinate planning,” says Tomasello. “It's not that humans have greater individual brainpower, it's that they have the ability to pool their cognitive resources and benefit from what others have learned.”

This evolutionary scenario sounds reasonable, but it will be difficult to prove. Hare plans to compare higher cognition between bonobos and chimps, which exhibit different levels of social tolerance, to see whether the connection between sociability and cognition holds up. Bonobos are quite tolerant; when they meet strangers, they have sex, whereas chimps often wage war, he points out.

Even before these studies are done, other researchers are taking notice—although they have yet to be convinced. “Evolutionary modification of fearfulness and aggressive tendencies might be a critical precursor to the evolution of social intelligence,” says ethologist Kay Holekamp of Michigan State University in East Lansing. “But I would certainly be surprised if that were all there were to [it].”

15. PALEOANTHROPOLOGY

# A Rare Meeting of the Minds

1. Ann Gibbons

At a historic meeting in France, rival paleoanthropologists gathered to review their field's progress and sketch its future

AIX-EN-PROVENCE, FRANCE—For an elite group of fossil hunters of a certain generation, life can be split into two time periods: B.L. and A.L., or Before Lucy and After Lucy. The “Lucy” in question, of course, is the petite, 3.2-million-year-old skeleton discovered in Ethiopia in 1974, which revolutionized our view of human origins. Famous fossil hunters, who rarely meet together, gathered here for 3 days last week to celebrate the 32nd anniversary of Lucy's discovery; they also came to pay tribute to French geologist Maurice Taieb, the man who found where Lucy and other famed hominids lived and died (see sidebar).

The 30-plus scientists at the invitation only conference* are members of one of the world's most exclusive clubs by dint of having discovered crucial hominid fossils. But they aren't exactly chummy: Several have not spoken to each other or been in the same room in more than a decade. So it's no surprise that they fought bitterly over questions of fossil interpretation and access. But their battles also provide a road map to where the field is headed: Was Lucy really our direct ancestor? Who came before her? When and where was our lineage born, and what sets it apart from other apes?

When a young American named Donald Johanson found the famed partial skeleton, researchers thought that Lucy's species, Australopithecus afarensis, was the earliest member of the human family, and that upright walking had evolved in the open savanna 3 million to 4 million years ago. But researchers have now glimpsed hominids nearly twice as old. And animal fossils, pollen, and geological clues at Hadar, Ethiopia, have revealed that Lucy's species walked in a grassy woodland with deciduous trees, reported Taieb, now of the Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnment (CEREGE).

Johanson, now a paleoanthropologist at Arizona State University in Tempe and a prominent popularizer of science, reported that the portals into past environments had shown that Lucy's species, found across Africa, was also remarkably adaptable. At last count, researchers had found 370 fossils of A. afarensis at Hadar alone, including males and females, infants, and adults who were alive 3 million to 3.4 million years ago. As the habitat became drier and more open, the species adapted. Their bodies and jaws grew, probably as they ate less fruit and more tuberous roots. The once-radical idea that these fossils were all members of one species that gave rise to our genus, Homo—and eventually led to modern humans—is now accepted by many researchers, said Johanson.

But despite the wealth of data on Lucy's species, old differences of opinion linger. Courtly paleoanthropologist Yves Coppens of the Collège de France in Paris—who co-discovered Lucy's species—politely demurred with Johanson's view at the meeting. Coppens maintains that two species of hominids lived at Hadar—and that neither led to modern humans.

That old feud has now burned down to embers, in part because emphasis has shifted to newly discovered fossils that spark heated debate. On the meeting's second day, talk turned to these more ancient and fragmentary specimens, most discovered in the past decade, that are vying for status as our earliest ancestor. First up was paleontologist Michel Brunet of the University of Poitiers, who brandished a jawbone of the oldest putative hominid, Sahelanthropus tchadensis, discovered in the Djurab Desert of Chad and dated to as early as 7 million years ago.

Brunet, who radiates both charm and an edgy humor, reviewed the traits that tie this stunning skull, nicknamed Toumaï, to human ancestors. The fossil is 95% complete, and Brunet says that the angle at which it sat atop the spine suggests it walked upright—a defining trait of humans and their ancestors but not apes. “Toumaï is not a chimpanzee. It is not a gorilla,” Brunet pronounced. That was a dig at two colleagues in the room, geologist Martin Pickford of the Collège de France and paleontologist Brigitte Senut of France's National Museum of Natural History, who have proposed Toumaï as an ancestor of apes rather than people. They repeat this view this week in the online journal PaleoAnthropology.

Soon it was time for Senut, one of the few women who co-leads a team. (The other leading woman, Meave Leakey, was invited but did not attend.) Senut showed new fossils of teeth and a thumb of a 6-million-year-old hominid called Orrorin tugenensis that she and Pickford discovered in the Tugen Hills in Kenya. Orrorin's teeth are primitive, but the shape of the thumb suggests that it was opposable and more modern than the thumb of Lucy's species, Senut said. That trait adds to their claim, based on a partial thighbone, that Orrorin walked in a more human way than Lucy did.

If Orrorin was more modern than Lucy, it must have given rise to the Homo lineage that led to modern humans, Senut and Pickford say. That would bump most of the fossils found by the other teams in the room, including Lucy, off the line leading to Homo.

Robert Eckhardt of Pennsylvania State University in State College then attempted to support Orrorin's claim to fully human walking by resurrecting controversial computed tomography (CT) scans of the interior of its thighbone (Science, 24 September 2004, p. 1885). Such scans, x-rays, and photographs can show the internal pattern of bone distribution, which can reveal whether an animal walked upright. But Tim White of the University of California, Berkeley, and his colleagues, who discovered a younger hominid, Ardipithecus, that they say is bipedal and may have led to Lucy, contend that the scans are of low quality and unreliable. For several years, White has repeatedly asked Pickford and Senut to provide a simple photograph of the interior of the thighbone at a point where it was broken and glued.

After seeing the 4-year-old scans yet again on-screen, White, who is known for his acerbic wit and has co-authored a state-of-the-art paper on how to use the CT method, blasted Eckhardt and called details of his talk a “diversionary tactic.” Eckhardt said he would like new CT scans but lacked permission and funding. (Ironically, their exchange took place against the backdrop of one of Eckhardt's slides that proposed: “Beginning of real cooperation on the structure of thought about hominid origins.”)

Pickford then made the startling revelation that he did not control access to fossils his team has found. He offered to provide access if he could. “Anyone is free to see the specimens. You need to contact Eustace Gitonga,” he said. Gitonga is director of the Community Museums of Kenya, which has custody of the Orrorin specimens, and issues permits to Pickford and Senut to search for fossils.

Brunet piped up that “it's not so difficult … to take a picture. I'm just asking why [no picture]?” Johanson, who was moderator, then ended the session, muttering that “everyone makes mistakes.”

The next day, Johanson applied a little spin control. “Every person here has a slightly different idea how to draw the [human family] tree,” he told a group of French science teachers invited to the last session. “But you should not let this distract you that there is probably more consensus about human origins today than ever before.” For example, although researchers argue over which early fossil was even a hominid, much less the first, each of the competing teams has independently concluded that their primate lived in the forest, not the savanna. White's colleague Doris Barboni of CEREGE reported, for example, that the 4.4-million-year-old Ardipithecus ramidus lived in a tropical woodland with palm trees.

Another positive trend was the easy camaraderie of the younger researchers, both during sessions and at breaks. At least a half-dozen were scientists from Ethiopia and Chad reporting on their impressive array of newly discovered hominid fossils. There were no Africans with Ph.D.s in human evolution research 30 years ago, noted the Tunisian-born Taieb. Now, he said, “there is a new generation.”

• *“Lucy, 30 years later,” 12–14 June, Aix-en-Provence, France.

16. PALEOANTHROPOLOGY

# Paleoanthropology's Unsung Hero

1. Ann Gibbons

In 1871, Charles Darwin speculated in the Descent of Man that humans had evolved in Africa. And he predicted that it would likely be geologists who found the missing fossil trail that led to where our lineage arose.

Almost 100 years later, the man who has best fulfilled Darwin's prophecy is indeed a geologist: Maurice Taieb, 71, of the French research lab CEREGE in Aix-en-Provence. Taieb has the rare distinction of discovering two of the most important sites in human evolution, both in Ethiopia. Although geological groundwork is critical for hominid paleontology, it is less glamorous than finding fossil bones, and so Taieb is far less famous than some of his fossil-hunting colleagues.

But for him, fieldwork has been its own reward. Born and reared in Tunisia, he calls the desert “magic.” As a graduate student back in the 1960s, he set out to explore the scorched earth of the Afar Depression, seeking signs of ancient lakes. He traveled only with an Afar guide, often on foot or with a donkey, and slept under little more than a mosquito net.

One day in 1969, Taieb had driven well beyond the end of the road, as was his habit, across a gravel-strewn plateau in the Awash valley, and come to an abrupt stop at the edge. When he stood on the rim overlooking the valley of Hadar, he was stunned by the layers of ancient sediments laid down over millions of years. After hiking down into the valley—alone, because his guide feared trouble from local tribes—he was overwhelmed by the fossils he found. Elephant bones and tusks were sticking out of the sandstone, and rhino and hippo bones were strewn on the surface. Taieb took photos, collected a few bones, and returned to Paris. There, he invited paleoanthropologist Yves Coppens to work with him; the pair was later joined by a young American named Donald Johanson and others.

In 1974, Johanson discovered the famous hominid skeleton called Lucy, transforming our view of human origins and establishing a new standard for international research in human origins. “Lucy was a turning point,” says paleoanthropologist Tim White of the University of California, Berkeley, who helped analyze her bones. “Lucy had a fundamental role in changing the structure of paleoanthropology in east Africa.”

Taieb also was the first to discover the site of Aramis, in the Middle Awash, which turned out to be the resting place of the 4.4-million-year-old hominid Ardipithecus ramidus. White thinks Ardipithecus may be a distant ancestor of Lucy—and our own lineage. Taieb never worked at Aramis, but he generously told White about it, paving the way for more than a decade of fruitful fieldwork in what White has dubbed the Grand Canyon of human origins.

Last week, at a rare face-to-face meeting of hominid discoverers organized by Taieb (see main text), two generations of researchers praised him. “Paleoanthropology is a field fraught with intense fighting and intense competition,” says Johanson. “Maurice is a man who, rather than usurping areas for his own aggrandizement, offered others opportunities.”