News this Week

Science  27 Apr 2012:
Vol. 336, Issue 6080, pp. 396
  1. Around the World

    1 - Paris
    Envisat Still Offline
    2 - Western Australia
    Breeding Humpbacks Get Safe Space
    3 - Mexico City
    Mexico Passes Tough Climate Change Law
    4 - Panama City
    ‘IPCC for Biodiversity’ Gets Final Approval

    Paris

    Envisat Still Offline

    CREDIT: ESA

    Things are not looking good for Europe's flagship Earth observation satellite Envisat. Ground controllers lost communication with the craft on 8 April and have been unable to reestablish contact. They have determined that the craft is still in a stable orbit and not spinning, ruling out a collision, and that its radar antenna and solar array are both intact.

    Envisat carries sensors for scanning land, sea, and atmosphere, and has been the mainstay of European environmental researchers for the past 10 years. The European Space Agency (ESA) hoped Envisat would last until ESA's next-generation Sentinel satellites are launched.

    ESA now has an agreement to get radar imaging data from Canada's Radarsat. Those using Envisat's radar altimeter also have alternatives. “We at least for the time being have [ESA's] CryoSat-2 to ensure continuity of polar altimetry,” says climate physicist Seymour Laxon of University College London. But for researchers studying air quality and atmospheric science “there is nothing to replace [Envisat's instruments],” says Robert Meisner of ESA's Earth observation program. The next generation of these instruments is due to fly on Sentinel 3, slated for launch in 2014. http://scim.ag/Envisat

    Western Australia

    Breeding Humpbacks Get Safe Space

    CREDIT: TARAS VYSHNYA/ISTOCKPHOTO.COM

    Every year, 20,000 or so humpback whales migrate north from Antarctica's feeding grounds to breed in the warmer waters of Western Australia. About 1000 of the whales of this “Breeding Group D” population head to Australia's Kimberley Coast, making it the largest humpback whale calving area in the Southern Hemisphere—and last week Western Australian officials announced that part of a planned marine park will be set aside to help protect the annual visitors.

    The Camden Sound Marine Park will span nearly 7000 square kilometers, and will include zones closed off to commercial fishing and others to protect the region's islands, shoals, and reefs. A “special purpose zone,” spanning about 25% of the park, will protect the whales, requiring vessels to stay at least 500 meters from the humpback mothers and calves.

    The whales remain in the warm waters for several months, before attempting the trip back to the Antarctic summer feeding grounds.

    Mexico City

    Mexico Passes Tough Climate Change Law

    CREDIT: JACK HOBHOUSE/ALAMY

    Mexico's legislature passed a strong, new climate change law on 19 April. The law includes provisions to mitigate climate change and requires 35% of the country's energy to come from renewable sources by 2024. It also includes a mandate to reduce carbon dioxide emissions by 30% below current levels by 2020 and 50% below current levels by 2050. Mexico is now the second country in the world, after the United Kingdom, to have legally binding emissions goals intended to reduce the impacts of climate change.

    Panama City

    ‘IPCC for Biodiversity’ Gets Final Approval

    Negotiators from 90 countries agreed this week on the final design of the Intergovernmental Science-Policy Platform on Bio diversity and Ecosystem Services (IPBES). Working under the auspices of the United Nations, IPBES will be analogous to the Intergovernmental Panel on Climate Change, creating regular assessments of the state of biodiversity around the world that will be geared toward policymakers (Science, 4 March 2011, p. 1139). Teams of volunteer experts will also highlight areas where more research is needed. Germany beat out several countries, including India, that are more biodiverse to host the IPBES, which will be headquartered in Bonn.

  2. Random Sample

    Noted

    Wondering how you can help prevent budget cuts to planetary science this year? Try a bake sale, says Alan Stern, of the Southwest Research Institute in Boulder, Colorado. Stern has proposed a National Planetary Exploration Car Wash & Bake Sale to be held 9 June as a way to raise awareness of potential cuts and how they might affect planetary research.

    Heavy Hitting

    CREDIT: (INSET) BRUCE M. SIMONSON; DON DAVIS

    The so-called Late Heavy Bombardment (LHB)—when comets and asteroids are thought to have pummeled Earth, the moon, and other inner bodies of the solar system—may have lasted longer than once thought.

    One explanation for the LHB, thought to have lasted between 4.1 billion and 3.8 billion years ago, is that migration of gas giant planets sent objects in the asteroid belt zooming toward the center of the solar system. Now, in one of two new studies in Nature this week, researchers suggest that the LHB was prolonged by later impactors that came from a largely extinct belt of asteroids known as the E belt.

    Rocks from lunar craters have provided much of the evidence for the LHB, but in the second Nature paper, scientists examining Earth-based evidence also found support for a longer onslaught. The flux of impactors, they report, was much higher 3.5 billion years ago than now. The new data came from spherule layers, which formed when rock vaporized by impacts condensed into molten droplets that were then preserved in the geologic record (inset).

    A Very Scientific Comic Book

    Take one Greenlandic graphic artist and add a group of Danish archaeologists and self-confessed “cartoon nerds” from the National Museum of Denmark in Copenhagen, and what do you get? A series of action-packed graphic novels on the prehistory of Greenland, from the peopling of the island 4500 years ago to the shamanic traditions of later Dorset culture hunters.

    CREDIT: ILLUSTRATIONS FROM TUTINEQ SIULLEQ/DE FØRSTE SKRIDT/THE FIRST STEPS © 2009, NUKA K. GODTFREDSEN, ILINNUISIORFIK AND THE NATIONAL MUSEUM OF DENMARK

    “We pulled together all the knowledge we could to make these subjective, fictional stories,” says Martin Appelt, an archaeologist at the National Museum of Denmark. Artist Nuka Konrad Godtfredsen discusses the storylines with the archaeologists and then bases his drawings on data such as scientific records of excavated artifacts and campsites or photographs of flint-knapping experiments. The first book in a planned series of four graphic novels appeared in 2009 in three languages: Danish, Greenlandic, and English. The second will appear in May.

    Robert Park, an Arctic archaeologist at the University of Waterloo in Canada, says these graphic novels will keep aboriginal communities abreast of research conducted on their ancient sites—a form of accountability that earlier archaeologists often neglected. “In my training as an archaeologist,” says Park, “presenting archaeological information back to the Inuit communities was just not on the radar.”

    Working with Godtfredsen on the illustrations has yielded scientific dividends: National Museum of Denmark archaeologist Bjarne Grønnow reexamined wooden artifacts from the 4500-year-old camp site of Qeqertasussuk and recently found that one bent and grooved strip formed the rim of an Arctic drum, pushing back the drum's history by 3500 years.

    “By having Nuka there visualizing the ideas that we have,” concludes Appelt, “it has forced us to be more specific about concepts we were once a little vague about.”

    By the Numbers

    0.66 million km3 Total volume of groundwater in Africa, according to a new estimate based on hydrogeological maps and preexisting studies published online 19 April in Environmental Research Letters.

    9,700 The number of people likely to die if a magnitude-7.3 earthquake occurs on a fault near Tokyo, according to a new study by the Tokyo Metropolitan Government.

    ScienceLive

    Join us Thursday, 3 May, at 3 p.m. EDT for a live chat with an expert on the search for extraterrestrial intelligence, also known as SETI. http://scim.ag/science-live

  3. Newsmakers

    They Said It

    “I think this a great way to show how biochemistry can daily impact their life. It also makes them a much better cook!”

    —Joseph Provost, describing his science of cooking class at Minnesota State University, Moorhead, at the American Society for Biochemistry and Molecular Biology annual meeting this week

  4. Public Health

    Europe's Embarrassing Problem

    1. Kai Kupferschmidt*

    Measles, an easily preventable disease, has made a comeback in one of the richest parts of the world. Public health experts are unsure how to fight back.

    Protected.

    Emma, 15 months old, gets vaccinated against measles and three other diseases in Berlin.

    CREDIT: JOCHEN ZICK/ZUMAPRESS.COM/NEWSCOM

    In April 2009, a young man traveled from Germany to the Razgrad district in northeastern Bulgaria carrying more than his suitcase and the money he had made as a construction worker in Hamburg: He was infected with the measles virus. Upon arrival, he touched off a wave of cases that spread from the northeast of the country to the southwest, sickening more than 24,000 people and killing 24. From Bulgaria, the strain, dubbed D4-Hamburg, was carried back to Germany, and also to Turkey, Greece, Macedonia, and other European countries.

    The chain of events, recently pieced together by European scientists using genetic and epidemiologic data, is typical for Europe's struggle against measles, a disease that is easy to prevent and that the continent once pledged to eliminate by 2010. While every country in the Americas, including its poorest, wiped measles off the map in 2002, Europe has been unable to do so—on the contrary. Cases have quadrupled since 2009; France alone had more than 15,000 last year.

    The reemergence has become a threat to other countries. In 2011, the United States had 222 cases, the Centers for Disease Control and Prevention reported last week—very few compared with Europe, but it was the highest number since 1996, and most importations come from Europe. “I feel very ashamed,” says Marc Sprenger, the director of the European Centre for Disease Prevention and Control (ECDC) in Stockholm. Luckily, high vaccination rates in the Americas prevent most imported infections from spreading.

    Measles' stubborn persistence in Europe would also be a stumbling block in any plan to eradicate the disease globally. “The problem in Europe is actually more serious” than elsewhere, says Diane Griffin, an immunologist and longtime measles expert at Johns Hopkins University in Baltimore, Maryland. “This is what will keep measles from being eradicated, I think.”

    Faced with the grim numbers and amid fears that two huge sporting events this summer could help the disease spread further, public health experts are campaigning hard to raise awareness of the dangers of measles. ECDC has made it one of its 2012 priorities, and several countries are organizing catch-up campaigns to ensure that people are getting the second vaccine dose necessary for full protection.

    Moving the goalposts

    One factor hampering control is the perception that measles is a harmless childhood disease. In fact, it's one of the deadliest infections in human history: Measles is estimated to have killed more than 2 million children each year before vaccines became available in 1963. Infection leads to a prolonged weakening of the immune system, and most measles deaths in the world are due to secondary bacterial or viral infections that are rarely lethal in rich countries. That's why India and sub-Saharan Africa have the highest measles mortality (see sidebar). But measles can also kill by itself; about one in 3000 cases in Europe is still fatal.

    There is an effective and inexpensive vaccine, however. Two doses, the first given between 11 and 14 months of age and the second between 15 and 23 months, protect more than 98% of vaccinated children at less than $1 per child. Most countries in Europe use a combined vaccine against measles, mumps, and rubella (MMR).

    Because the virus has no other host than humans, measles could in theory be eradicated through mass deployment of the vaccine, a solution that experts have talked—and dreamed—about for decades. The success in the Americas has shown that it's possible, and in 2002, WHO's European Region—which includes Russia, Ukraine, and Turkey—set a deadline of 2010 for elimination, the regional equivalent of eradication.

    It didn't even come close. Although cases fell initially, they started to climb again in 2009. In September 2010, WHO moved the goalposts by agreeing on a new 2015 deadline. But that, too, now seems close to impossible. There were about 37,000 reported measles cases in the European Region in 2011. (More than 30,000 were in the European Union, the richest part of the region.)

    And public health experts are worried that 2012 might see another spike because of the European Football Championship in June. Up to a million spectators are expected to converge on Poland and Ukraine, the cup's hosts. Ukraine has already seen more than 7000 cases this year, and the peak transmission season is just starting. ECDC is urging football fans to make sure they are vaccinated. The Olympic Games in London, a month later, could become another viral hub.

    A rash of new cases.

    Measles has been on the rise in WHO's European Region since 2007.

    GRAPH SOURCE: WHO

    Making it mandatory

    Europe's failure has multiple and complex causes. To protect an entire population against measles, at least 95% of its members needs to be vaccinated, which has proven very difficult. Many parents underestimate the risk of the disease and overestimate the vaccine's side effects. Allegations by British gastroenterologist Andrew Wakefield that the MMR vaccine can lead to autism were particularly damaging; in response, vaccination rates plummeted in the United Kingdom and Ireland. The connection was never replicated, and Wakefield's work was later shown to be fraudulent. But the scare resulted in a generation of children that is less protected.

    Anthroposophic communities and certain Protestant churches are opposed to vaccinations on philosophical or religious grounds. Minorities and marginalized groups, such as the Roma, can be hard to reach, as well. And there are more practical reasons for why children don't get vaccinated, says Ole Wichmann of the Robert Koch Institute, the German center for disease prevention and control: “One of the most common is that parents simply forgot it or did not have the time.”

    Similar obstacles occur in the Americas, however, and experts have difficulty explaining the huge gap in success. A key factor may be that in the United States and many countries in Latin America, children must be vaccinated before they enter school, Griffin says. “There is no reason to think we wouldn't have the same kinds of problems in the Americas, if vaccination wasn't mandatory,” she says. But Sprenger and Wichmann say that would run into major legal and ethical problems in Europe and would not be accepted. But it would help if health officials were allowed to go into schools to offer vaccination, Wichmann says.

    Scientists are looking for other solutions, as well. “We need to use social media more,” Sprenger says. “We need to look for new approaches.” ECDC is bringing together professionals in public relations, marketing, and communications at a “freethinkers meeting” this month to brainstorm about new ways to promote measles vaccination.

    Perhaps simply making life easier for parents would help, says Robb Butler of WHO's European Regional Office: “We lead these fast and furious lives now, but immunization campaigns haven't changed.” He suggests offering parents an opportunity to get their children vaccinated after working hours or giving workers a few hours off for the shots. “It's all posters, brochures, and stickers,” Butler says. “But a sticker won't change a thing if you do not have the time.”

    ECDC is also trying to get doctors more involved. “Health professionals have a huge responsibility. There is no room for complacency,” Sprenger says. Doctors and nurses also need to be vaccinated themselves, Wichmann says; not all are. “If they are not, they shouldn't be allowed to work in intensive care units or oncological wards where there are vulnerable patients,” he says.

    The tragedy is that countries of the First World appear to have forgotten how important vaccination is, says Seth Berkley, director of the GAVI Alliance. His wife, a physician who ran the intensive care unit of a major teaching hospital in New York, has never seen a case of measles, Berkley says. “I have been in a refugee camp and watched measles come through, and every day I saw the little graves of all the babies who were buried. You don't forget that.”

    • * Kai Kupferschmidt is a science writer in Berlin.

  5. Public Health

    After a Successful Decade, Global Fight Appears Stalled

    1. Kai Kupferschmidt

    A new report estimates that global measles deaths declined dramatically between 2000 and 2007, but since 2007, the numbers have essentially remained flat.

    It's not just Europe that has trouble getting measles under control. A new report from the World Health Organization (WHO), the U.S. Centers for Disease Control and Prevention (CDC), and Pennsylvania State University estimates that global measles deaths declined dramatically between 2000 and 2007, thanks in part to a new partnership called the Measles Initiative. But since 2007, the numbers have essentially remained flat. The report, published in The Lancet this week, estimates that 139,000 children died of measles in 2010—an impressive 74% reduction since 2000, but short of WHO's goal of 90%.

    The global recession is largely to blame, says Stephen Cochi of CDC, who was not involved in the study. Funding for the Measles Initiative, in which CDC is a partner, dropped by 75%, Cochi says; as a result, campaigns were delayed, target groups were narrowed, and corners were cut.

    To arrive at the estimates, the scientists used a new method that integrates data about vaccine coverage and efficacy with actual surveillance numbers, says co-author Peter Strebel, a measles expert at WHO. “These are the best estimates we have ever had,” Strebel says. Africa saw the greatest reduction in mortality—from 337,000 in 2000 to 50,000 in 2010. Deaths dropped from an estimated 88,000 to 66,000 in India, which now accounts for almost half of the global mortality.

    The paper is another reality check—along with Europe's troubles (see main text)—for those hoping to eradicate measles. WHO has not set a deadline for eradication, but five of the six WHO regions—the entire world minus Southeast Asia—have pledged to eliminate the disease by 2020.

    Still, measles researchers feel confident that mortality will drop further eventually. Funding for the Measles Initiative has picked up, Cochi says. India recently adopted a two-dose vaccination strategy that provides optimal protection, and numbers there are bound to go down. “They have made great progress in 2011 and 2012,” Strebel says. “That is not yet captured in the data.”

  6. Evolution of Language

    Experiments Probe Language's Origins and Development

    1. Dennis Normile

    In a new twist for an old field, language researchers are heading to the laboratory to test hypotheses.

    KYOTO AND TOKYO—Playing slide whistles. Learning fictitious “alien” languages. Making Stone Age tools. Those all sound more like hobbies than scientific pursuits. But such activities are at the heart of recent efforts to understand the emergence and evolution of language. And the trend shows how much the field is changing.

    Theorizing once dominated work on the origins of language. More recently, researchers have gone into the field to study how songbirds learn to sing and into nurseries to observe the vocalizations and gestures of children for hints of how language may have emerged. Now researchers are testing their hypotheses under experimental conditions. “Five or 6 years ago, it seemed an odd idea that we could do experiments in language evolution, but that has changed,” says Simon Kirby, an evolutionary linguist at the University of Edinburgh in the United Kingdom.

    Knapping know-how.

    Archaeologist Bruce Bradley reproduces Late Acheulean stone axes similar to one from 500,000 years ago (top right). Brain imaging (right) shows that stone toolmaking activates areas also involved in language.

    CREDITS (TOP TO BOTTOM): (INSET) JAN APEL; STEFFAN KLEMENIC; © A. FAISAL ET AL., PLOS ONE 5, 11 (3 NOVEMBER 2010)

    The experiments, observations, and even some theorizing were on the agenda at the Evolang9 conference in Kyoto and a follow-up forum in Tokyo last month.* By design, these meetings bring diverse views together to unravel questions not likely to be answered by work within one discipline (Science, 21 May 2010, p. 969).

    Cognitive tools

    Evo-devo, or evolutionary developmental, theorists as far back as Charles Darwin in The Descent of Man have speculated that there may be a connection between language and stone toolmaking (Science, 6 February 2009, p. 709). “There is a rich line of people who tried to look at the archaeological record of the making of stone tools and the evolution of language,” says Michael Arbib, a neuroscientist at the University of Southern California in Los Angeles. “You look at the archaeological relics,” he says, and “try to infer the behavior involved” in making them.

    The inferences start with the earliest known examples of human technology, Oldowan cutting tools. Dating back 2.6 million years, they are simple stone flakes with sharp edges knapped off crude “cores” using “hammerstones.” Such tools gradually became more refined, achieving a high level of sophistication about 700,000 years ago with Late Acheulean handaxes. High-tech by comparison, these were deliberately crafted into oval or teardrop shapes in multistep manufacturing processes that required planning and significant skill. One hypothesis is that the cognitive capabilities that supported toolmaking gave the toolmakers language-ready brains; then the benefits of instructing succeeding generations in how to make tools drove the emergence of language.

    Evidence supporting this hypothesis began accumulating in the past decade as brain imaging found overlaps in the neural areas associated with language and those involved in tool use. More recently, groups led by Dietrich Stout, an archaeologist at Emory University in Atlanta, and Thierry Chaminade, a cognitive neuroscientist at Aix-Marseille University in Marseille, France, have taken to actually reproducing stone tools while tracking neural activity with positron emission tomography. In a series of experiments reported over the past 5 years, they showed that Oldowan toolmaking activates the left ventral premotor cortex, a region previously shown to be involved in both manual grip coordination and phonological processing. Late Acheulean tool production relies on those same regions, they found, plus other areas of the brain, including the inferior frontal gyrus, which is associated with abstraction and hierarchical organization (needed for executing subgoals along the way to a final product, for example), as well as larger scale discourse and language processing.

    Follow-up experiments in which Bruce Bradley, an archaeologist at the University of Exeter in the United Kingdom, wore a data glove to record left hand finger movements suggested that it was the cognitive demands of making Acheulean tools—not left hand manipulation—that lit up the right brain.

    The results “establish plausible evolutionary links” between specific toolmaking skills and language processing, Stout and Chaminade concluded in a review that appeared in Philosophical Transactions of the Royal Society B in January 2012.

    But another step was needed to go from a language-ready brain to language. To see if teaching toolmaking had a role, Stout and colleagues used functional magnetic resonance imaging to capture brain activity of subjects as they watched an accomplished knapper at work. When observing Late Acheulean toolmaking, only those observers themselves skilled at toolmaking activated the intention-reading areas of the brain. They understood the ultimate goal of the craftsman, while the neophytes did not. The drive to bridge this gap in understanding “could have provided an adequate scaffold for the evolution of intentional vocal communication,” Stout and Chaminade wrote in their review.

    Whatchamacallit?

    Randomly generated syllable strings acquired languagelike properties as subjects used them to pick images from an array.

    CREDIT: ROB CLARK

    Although neither Stout nor Chaminade attended the recent meetings, their work was at the center of many discussions. The co-opting of existing capabilities for new uses “is the way that evolutionary biologists typically explain major evolutionary innovations,” said evolutionary biologist Russell Gray of the University of Auckland in New Zealand during his talk. Gray and others gave tantalizing glimpses of work under way that builds on the Stout-Chaminade work to suggest that, among other things, the origins of abstraction and syntax might lie in toolmaking pedagogy.

    But not everyone was convinced. Massimo Piattelli-Palmarini, a biolinguist at the University of Arizona in Tucson, later told Science that a more genetic basis for language “will one day be discovered.” For now, evo-devo thinkers seem to have the upper hand.

    The cultural factor

    Those working on the cultural side of language evolution are also embracing experiments. Kirby argues that our modern use of language results from a dual inheritance. On one side, genetics gave us the cognitive and physiological capabilities for language. But language itself is passed from generation to generation by teaching and learning, a cultural process. “The language faculty evolved biologically, but languages themselves evolved culturally,” Kirby says. Kirby is particularly interested in the structure of language, specifically how meaningless syllables can be combined to make meaningful words, what he calls combinatoriality; and how words combine into phrases, compositionality. Thanks to these two properties, “I can produce sentences I've never said before and you've never heard before and yet you can understand me,” Kirby says.

    Kirby and colleagues wanted to investigate how language acquired these structural aspects. Or, as his University of Edinburgh collaborator Hannah Cornish puts it, “What happens when you have some loose ideas of concepts and some ability to produce signals, but no preexisting system of combining these things together.” They hypothesized that the transmission of a language from generation to generation played a critical role. To test this idea, they recruited volunteers to learn a fictitious “alien” language. (Calling it “alien” attracted participants.) Working at computer terminals, they were shown a series of words and the images they referred to. The words were actually randomly generated strings of syllables. Each of the images had a unique combination of color, shape, and patterning. The participants were then shown images and asked to type in the appropriate words. They were also asked to produce words for images with color, shape, and patterning combinations they hadn't specifically learned. The words as given by one participant were used to train the next in line, a process called iterated learning that resembles the cultural transmission of a language among generations.

    Tuning up.

    By passing through a succession of learners playing slide whistles, random notes became musical phrases.

    CREDIT: TESSA VERHOEF (2)

    Researchers tested different scenarios of that basic approach. In one, instead of individuals in each generation, there were pairs of participants who used the alien language to “communicate,” picking images from an array. (The pairs were separated and interacted via computer terminals so they could not point or gesture.) The words they recalled after the communication exercise were used to train the next pair in the chain. Other pairs simply did the communication task, again via computer terminals, over and over without the “language” being passed to a new generation.

    When pairs of humans learned the words, used them to communicate, and then passed them on through several generations, a compositional structure emerged. Parts of the words—the prefix, for example—consistently corresponded to color, and other parts became associated with shape or pattern. Succeeding pairs found the language progressively easier to learn and use accurately. Pairs at the ends of the chains could even recombine the parts of the words to accurately label images they had not specifically learned. When the language passed through a chain of individuals, thus skipping the communication step, it became ambiguous, with one “word” having multiple meanings. The pairs that worked just on the communication task eventually agreed on linking words with images, but the language remained an idiosyncratic pairing of syllables and meaning with no standardization or compositional structure. To get structural properties and improve learnability, “what is really crucial [is] a combination of naive learners and communication,” Kirby says.

    Kirby admits that the linguistic structure they're seeing may be an artifact from people who already have language. But Tessa Verhoef and Bart De Boer of the University of Amsterdam in the Netherlands, devised an experiment that avoided language altogether: Participants use slide whistles to produce whistling sounds unconnected to any meaning. The whistles produced by one participant were used to train the next. Again, structural elements—down-up and up-down whistles, repeated notes—emerged that were systematically reused and combined in various ways. And after several iterations, the whistles “become more learnable [and] more reproducible,” Verhoef says.

    In addition to experiments with human subjects, Kirby and his colleagues ran computer simulations of populations acquiring language through iterated learning. Their computer model allowed them to test whether the tendency toward structure was likely to be innate—that is, genetically hard-wired—or the result of cultural transmission. Their work suggests that the structural properties seen in languages are more likely produced by the dynamics of cultural transmission. (The group's computer simulations were reported in the Proceedings of the National Academy of Sciences in 2007, and the results of the initial laboratory experiments appeared in the same journal in 2008. More recent work has yet to be published.)

    The Kirby and Verhoef–De Boer experiments were “quite impressive and clever,” says Robert Van Valin, a linguist at Heinrich Heine University in Düsseldorf, Germany. That the computer simulations and human experiments agreed is significant, he says; it argues for the importance of cultural factors in the evolution of language. But there were still questions about what the experiments say about an ancient phenomenon. “It demonstrates one plausible path” for the emergence of language structure, says Sotaro Kita, a psychologist at the University of Birmingham in the United Kingdom.

    Name that tune.

    Domesticated Bengalese finches (left) outsing wild white-rumped munias (right).

    CREDIT: MAKI IKEBUCHI

    Kirby says certain of his group's hypotheses are bolstered by other studies. They have done some experiments using spoken words and have gotten the same results—with structure emerging after passage through several generations. Also, he says their experimental findings suggest that languages used by larger and more diverse groups, with more transmission to naïve learners, tend to be simpler. More complex languages appear to arise when user groups are smaller and more cohesive. That is consistent with what Gary Lupyan of the University of Wisconsin, Madison, and Rick Dale of the University of California, Merced, found in a survey of 2000 languages reported in PLoS ONE in 2010. “The analyses suggest that languages spoken by large groups have simpler inflectional morphology than languages spoken by smaller groups as measured on a variety of factors,” the pair wrote. Like organisms, language structures appear to adapt to their environment.

    More evidence that complex language arises in close-knit, stable communities comes from a study of songbirds presented at the Tokyo Evolutionary Linguistics Forum by biopsychologist Kazuo Okanoya of the University of Tokyo. He reported that long-domesticated Bengalese finches have much more complex songs than their close cousins that live in the wild, white-rumped munias. Okanoya says that in the wild, the song needs to be simple and distinct so females can find males of their own species. But in a birdcage full of Bengalese finches, females take mastery of a complex song as a sign of male fitness. “Domestication freed songs from the function of species identity and female choice promoted complexity in Bengalese finches,” Okanoya concludes in a paper now in press at Interaction Studies. By extension, Okanoya says human self-domestication could have set the stage for human language to gain complexity.

    No one line of investigation is going to answer all the questions, Kirby says. Understanding the evolution of language “requires a convergence of evidence from an extraordinarily diverse set of disciplines,” he says.

    That conciliatory tone echoed throughout Evolang9. People spoke of fitting together the pieces of a very complex puzzle. A new generation of language researchers “is more interested in an interdisciplinary approach and more tolerant of complexity,” says Rafael Núñez, a cognitive scientist at the University of California, San Diego. That bodes well for the Evolang conferences, which were founded on the notion that all those studying language evolution should have something to say to one another.

    • * Ninth International Conference on the Evolution of Language, Kyoto, 13–16 March. Tokyo Evolutionary Linguistics Forum, 19 March.

  7. Evolution of Language

    Where Time Goes Up and Down

    1. Dennis Normile

    At the Tokyo Evolutionary Linguistics Forum, researchers presented an example of a different way of thinking—and gesturing—about time: topographically.

    In Western cultures, the future lies ahead; the past is behind us. These notions are embedded in both gestures and spoken metaphors (looking forward to next year or back over the past year). A forward hand motion typically accompanies talk of the future; references to the past often bring a wave over the shoulder.

    It is hard for most Westerners to conceive of other ways of conceptualizing time. But in 2006, Rafael Núñez, a cognitive scientist at the University of California, San Diego, reported that for the Aymara, an ethnic group of about 2 million people living in the Andean highlands, in both spoken and gestural terms, the future is unseen and conceived as being behind the speaker; the past, since it has been witnessed, is in front. They point behind themselves when discussing the future. And when talking about the past, Aymara gesture farther in front of them the more distant the event (Science, 23 June 2006, p. 1723).

    Heads up.

    This Yupno man of Papua New Guinea points downhill when speaking of the past, whether facing uphill (left) or downhill (right).

    CREDIT: R. NÚÑEZ, K. COOPERRIDER, AND J. WASSMANN

    At the Tokyo Evolutionary Linguistics Forum, Núñez presented another example of unusual thinking—and gesturing—about time: The Yupno people, who inhabit a remote valley in Papua New Guinea, think of time topographically. No matter which way a speaker is facing, he or she will gesture uphill when discussing the future and point downhill when talking about the past. “It can only occur in small societies that share an ecological niche,” Núñez says of their finding, in press at Cognition. These different abstractions of time, including gestures, indicate the importance of the cultural aspects of language evolution, he contends.

    Núñez's “very interesting” Yupno study “provides a tiny glimpse into the way one group of people relates to their world linguistically and cognitively,” says Erica Cartmill, a psychologist at the University of Chicago in Illinois who studies the use of gesture by great apes and children. She says more such comparative studies would help clarify the relationship between gesture, speech, and cognition in different cultures.

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