News this Week

Science  13 Jan 2012:
Vol. 335, Issue 6065, pp. 150
  1. Around the World

    1 - Bethesda, Maryland
    Acting Director Discusses New Translational-Science Center
    2 - Rehovot, Israel, and Leipzig, Germany
    Joint German-Israeli Research Center Planned
    3 - Bhubaneswar, India
    Singh Promises Windfall for India's Scientists
    4 - Ashmore Reef, Australia
    Dwindling Sea Snakes
    5 - Ellesmere Island, Canada
    Astronomy in the High Arctic
    6 - Washington, D.C.
    Report Challenges Ambitious U.S. Climate Research Plan

    Bethesda, Maryland

    Acting Director Discusses New Translational-Science Center

    CREDIT: NIH

    This month, the National Institutes of Health (NIH) launched a new $575 million center that aims to tackle bottlenecks in drug development and speed the translation of basic discoveries into therapies. In an interview with ScienceInsider, Thomas Insel, the acting director of the National Center for Advancing Translational Sciences (NCATS), discussed the aims, structure, and temporary leadership of the controversial new center.

    Insel dismissed reports that industry is skeptical: Industry leaders told NIH that they would “love to have help” with improving their R&D efforts, Insel said. Insel also clarified that he is not a candidate to become NCATS's permanent director. http://scim.ag/TomInsel

    Rehovot, Israel, and Leipzig, Germany

    Joint German-Israeli Research Center Planned

    The Munich-based Max Planck Society is teaming up with Israel's Weizmann Institute of Science to create a joint center devoted to studying archaeology and human evolution, to be based in both Rehovot, Israel, and Leipzig, Germany. The center will focus on questions such as the timing of cultural change over the past tens of thousands of years and the nature of coexistence between Neandertals and modern humans.

    On 11 January, Max Planck President Peter Gruss, and Daniel Zajfman, president of the Weizmann Institute in Rehovot, signed a contract to create the new Max Planck Weizmann Center for Integrative Archaeology and Anthropology, worth about €5 million over the next 5 years. It will be funded by the Max Planck's Minerva Foundation, which has supported German-Israeli collaborations since the 1960s.

    The money will fund up to 10 postdocs or graduate students in each city, says anthropologist Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology in Leipzig. It will also support infrastructure and equipment. Hublin and archaeologist Steve Weiner of the Kimmel Center for Archaeological Science at the Weizmann will co-direct the new center. http://scim.ag/PlanckCenter

    Bhubaneswar, India

    Singh Promises Windfall for India's Scientists

    India's Prime Minister Manmohan Singh has vowed to more than double his nation's spending on R&D over the next 5 years and build two major research facilities. The pledge, made 3 January at the annual Indian Science Congress, is expected to be a highlight of the government's new 5-year plan being finalized before its submission to parliament in March or April.

    Singh said he will seek to boost the country's R&D expenditures to at least 2% of gross domestic product by 2017, up from the current 0.9%. According to his target for the central government, over the next 5 years public R&D spending would rise to about $8 billion per year, up from $3 billion spent in 2011. The R&D windfall stems in part from Singh's belief that Indian scientists are not keeping pace with peers in China and elsewhere. “Over the past few decades, India's position in the world of science has been declining, and we have been overtaken by countries like China. Things are changing, but we cannot be satisfied with what has been achieved,” Singh said. “We need to do much more to change the fate of Indian science.” http://scim.ag/Indiaresearch

    Ashmore Reef, Australia

    Dwindling Sea Snakes

    Snake shortage.

    Sea snakes like this Stokes' sea snake (Astrotia stokesii) are becoming rarer in parts of the Pacific Ocean.

    CREDIT: EVA BOOGAARD/LOCHMAN TRANSPARENCIES

    Sea snakes could be going missing from a haven in the Pacific Ocean. Ashmore Reef, a colorful marine community off the coast of western Australia, has long been considered a hotbed of sea snake diversity. Here, 17 species, including three endemics, ply the waters. In surveys conducted throughout the 1990s, Michael Guinea of Australia's Charles Darwin University found up to 70 snakes per hectare in this reef; now there is less than 1 snake per 10 hectares, he reported last week at the annual meeting of the Society for Integrative and Comparative Biology in Charleston, South Carolina. Anecdotal evidence suggests the loss may extend at least 1000 kilometers down the northern coast of western Australia. The reef still looks pristine, with coral and sea grass intact. So it seems unlikely that climate change or increases in reef-side human activity are solely to blame. Guinea suggests seismic surveys in the area may have contributed to the decline of the sea snakes—possibly through damaging sound waves because the snakes seem to be very sensitive to minor changes in the environment—but that idea has yet to be tested.

    Ellesmere Island, Canada

    Astronomy in the High Arctic

    Astronomy in the cold.

    The Canadian High Arctic could make a good site for space viewing.

    CREDIT: PIERRE FOGAL/CANDAC

    Move over, Antarctica: A new study suggests that the Canadian High Arctic is also a good spot for ground-based optical astronomy. Both locations offer frigid temperatures, dry air, and endless nights, but the Great White North has some practical advantages over the Antarctic, according to the study, in press at Publications of the Astronomical Society of the Pacific.

    The paper describes data collected by an all-sky wide-field camera mounted under a Plexiglas dome on the roof of Canada's Polar Environment Atmospheric Research Laboratory at 80° north latitude. The Arctic site, the study found, has very clear, dark skies, making it good for high-quality photometry. It also appears not to suffer from strong low-level atmospheric turbulence found on the Antarctic plateau, which can distort images. And unlike Antarctica, the Canadian site is accessible via road and has an all-weather airstrip large enough for jet aircraft. Overall, the study found that spectroscopy can be done at the Arctic site 68% of the time and high-precision photometry about half the time. http://scim.ag/HighArctic

    Washington, D.C.

    Report Challenges Ambitious U.S. Climate Research Plan

    A National Research Council (NRC) committee has chided a federal climate change research program. The panel, which advises the 21-year-old U.S. Global Change Research Program (USGCRP), criticized the program for planning to broaden its climate activities without the expertise, governance structure, or prospect of sufficient funding to make it work.

    In its report, the NRC committee commended the USGCRP, an interagency coordinating group, for the general idea of broadening its program beyond basic climate change science. In its recent draft 10-year strategic plan, program officials write that they intend to coordinate research that would support society's efforts to reduce greenhouse warming and to adapt to any unavoidable global change.

    But, according to the report, “the USGCRP and its member agencies and programs are lacking in capacity to achieve the proposed broadening of the Program.” They're missing in-house expertise to integrate the needed social and ecological sciences or to develop the capacity to support decision makers. USGCRP officials counter that they are already working on involving social scientists and similar experts in their work and reworking the governance structure. http://scim.ag/USGCRP

  2. Random Sample

    Rhesus Pieces

    CREDIT: OREGON HEALTH & SCIENCE UNIVERSITY

    Rhesus monkeys Roku and Hex are two of the world's first lab-generated chimeric primates—each is composed of cells representing as many as six distinct genomes. Irresistible cuteness aside, the experiments that produced these monkeys are helping researchers better understand primate embryonic stem (ES) cells. For decades, scientists have used mouse ES cells to make chimeras. They add a few of these nondifferentiated cells into an early mouse embryo. The animal develops normally, incorporating the new cells into its tissues. When Shoukhrat Mitalipov and his colleagues at the Oregon National Primate Research Center in Beaverton tried the same test with rhesus ES cells, they found that the ES cells were unable to incorporate into the host embryo; the developing fetuses contained no trace of the added cells. The only way the researchers were able to make chimeric monkeys was to fuse several very early stage embryos into one. That is consistent with a growing body of evidence that primate ES cells—including human ES cells—may represent a slightly later stage of development than mouse ES cells. That may help explain why recipes that turn mouse ES cells into specific tissues don't work as well with human cells.

    Better Networking Through Chemistry on Fakebook

    CREDIT: COURTESY OF RUSSEL TARR

    If you asked hydrogen what its job is, what would it say? According to hydrogen's “Fakebook” profile, its job is to be “rocket-ship fuel.” Furthermore, its relationship status is “bonded.” And carbon, nitrogen, and oxygen are its friends.

    Fakebook (http://classtools.net/fb/home/page) is a Facebook-look-alike Web site created in January 2011 by Russel Tarr, a teacher at the International School of Toulouse, France. The Web site is rapidly becoming a popular teaching tool for science, history, and other school subjects, with a quarter of a million hits per week, Tarr says. In December alone, 14 Hydrogen profiles appeared on the site. “Kids love Facebook, and you always have to latch on to what they're enthused about and channel it into the classroom,” he says.

    Each of the students in Forest Grove, Oregon, teacher Tammy Johnson's biology class wrote a profile for a different cell organelle—and then Johnson had them post on one another's walls as a way to think about how the cell parts interact. “It puts it into a context that they're more familiar with,” Johnson says.

    Students in Lee Ferguson's Advanced Placement (AP) biology class in Allen, Texas, meanwhile, made profiles for animals. Gerald the giraffe, for example, notes that he sleeps only 20 minutes a night—“sort of like an AP student.” Writing on Gerald's wall, an acacia tree complains about being eaten. “I'm really stressed,” the tree writes. “I've just got a lot of things eating at me right now.”

    Other Fakebook friends run to the geometric. The rectangle laments that its birthday is “disputed” because it doesn't know if it was invented or discovered. It also notes, ruefully, that it “can be a bit square sometimes.”

    By the Numbers

    15% — Improvement in cars' average gas mileage from 1980 to 2006. Although average fuel efficiency increased by 60% in that time, bigger and more powerful cars account for the disparity, according to a report in American Economic Review.

    54% — Percentage of clinical trials that were still unpublished 30 months after they ended, according to a survey of 635 trials described last week in the British Medical Journal.

    16% — Increase in toxic chemicals released into the environment from 2009 to 2010, reversing a previous downward trend since 2006, according to a 5 January report by the U.S. Environmental Protection Agency.

  3. Newsmakers

    That's ‘Professor Sir’ to You

    CREDIT: U. MONTANA/© THE NOBEL FOUNDATION 2010 (2)

    In a New Year's tradition dating back to the days of Queen Victoria, the British monarch handed out 27 knighthoods on 31 December. This year, a number of scientists can now address themselves as “Sir” or “Dame.” The new knights include three Nobel laureates: University of Manchester physicists Andre Geim and Konstantin Novoselov, who received the 2010 physics Nobel Prize for their work on graphene, and structural biologist Venki Ramakrishnan of the MRC Laboratory of Molecular Biology in Cambridge, who shared the 2009 Nobel Prize in physiology or medicine for discovering the structure of the ribosome. Queen Elizabeth II will also be knighting American-born climate researcher Robert Watson, who formerly headed the Intergovernmental Panel on Climate Change and now serves as scientific advisor for the U.K. Department for Environment, Food and Rural Affairs, as well as several clinical researchers and a mathematician. Royal Society of Chemistry President David Phillips and two other scientific researchers are receiving a different honor, Commander of the Order of the British Empire. The knighting ceremonies will take place later this year.

  4. Archaeology

    The Peopling of the Aleutians

    1. Michael Balter

    Few Aleuts still live in their ancestral homeland, but their genetics and archaeology offer a rare glimpse into one of humanity's last great migrations—and into the mysterious peopling of the Americas.

    Refuge from the winds.

    A narrow isthmus separates Adak's Clam Lagoon (left) from the stormy Bering Sea.

    CREDIT: MASAYUKI TORII

    ADAK ISLAND, ALASKA—Clam Lagoon, at the northern edge of this volcanic island, is a peaceful refuge from the wind-ravaged tides of the Bering Sea. Sea otters do the backstroke in its tranquil waters, and puffins and murrelets roost on the treeless shores. About 7000 years ago, kayak-paddling humans arrived here, setting up housekeeping on a bluff overlooking both the lagoon and the sea. Exceptionally well-adapted to maritime life, these first colonists promptly set about exploiting the local riches: They ate the otters and the birds, as well as seals and sea lions. They fished for cod and greenlings with hooks made from the birds' wing bones, and they made tools using obsidian brought from another island hundreds of kilometers away. Before long, a smaller group left Adak to colonize yet more islands to the west.

    These people, the ancient Aleuts, began exploring the 2000-kilometer Aleutian archipelago—the world's longest—at least 9000 years ago. Because they had the islands to themselves for thousands of years, researchers say the archipelago is a living laboratory for studying human migratory behavior. “I don't think there is a better model than the Aleutians,” says geneticist Michael Crawford of the University of Kansas, Lawrence.

    Sadly, most of the Aleuts were evacuated from their ancestral islands during World War II, never to return. And yet Adak today has become the center of intense exploration into when, how, and why the Aleutians were peopled. Many of today's Aleuts can trace their ancestry back to the islands' first inhabitants, so “the Aleutians are a perfect storm of deep time depth,” says Anna Kerttula de Echave, director of the National Science Foundation's (NSF's) Arctic Social Sciences Program, which funds much of the work in the islands. “Only in a few places on the globe do you find such a continuous record of human occupation.”

    The Aleuts' story also opens a window into the peopling of the Americas as a whole. The Aleuts descend from ancestors who lived in Asia at least 13,000 years ago, making them part of the great migrations across the now-submerged Bering Strait land bridge into North America. Their history is obviously distinct from that of the groups who continued farther south into continental North and South America. But because the Aleuts have been relatively isolated for so long, researchers can more clearly read their ancient prehistory from their genes and archaeology, a task more difficult farther south where internal migrations may have blurred the earliest records.

    To some, the Aleuts' maritime adaptations strengthen the idea that the first Americans were sea travelers (Science, 4 March 2011, p. 1122). “The Aleutians show that a coastal route is entirely reasonable,” says archaeologist Lucy Johnson of Vassar College in Poughkeepsie, New York. Others counter that the Aleutians were settled too late to have a bearing on the land-versus-sea debate. “I have great difficulty with this notion,” says archaeologist Don Dumond of the University of Oregon, Eugene.

    Either way, the story of the Aleutians reveals how maritime migrations work. “We are coming to understand the dynamics of island colonization,” Crawford says.

    Two waves

    The written history of the Aleutians starts in 1741, when Russian explorers led by Vitus Bering discovered the Aleuts and changed their lives forever. At the time, the Aleuts were hunting sea mammals and living in rectangular huts. The Russians turned the Aleutians into a fur factory, pressing the Aleuts into servitude and moving them from island to island. Historians estimate that they numbered up to 16,000 in 1740, but by 1900, disease, starvation, and suicide had slashed their population by up to 90%.

    Digging deep.

    Archaeologists are finding clues across the Aleutians, including at Adak's Clam Lagoon (left) and on Kiska, where Veronica Lech of the Memorial University of Newfoundland holds an ancient sea cow rib.

    CREDITS (TOP LEFT TO RIGHT): LYN GUALTIERI; COURTESY OF VERONICA LECH

    The Americans who took over in 1867 were apparently more benign: By 1920, Aleut numbers began to bounce back, and they grew from about 3000 to 8000 by 1980.

    Beginning in the late 1800s, scientists began to visit the Aleutians, and in the 1930s famed Smithsonian anthropologist Aleš Hrdlička gathered dozens of skeletons. Hrdlička concluded that the Aleutians had been settled by two consecutive groups: the original settlers, the Paleo-Aleuts, who had high and narrow skulls (dolichocranic), and the Neo-Aleuts, who had wider, rounder skulls (brachycranic).

    That basic idea has been confirmed by more recent research. In new studies of 86 of Hrdlička's skeletons, ranging from 3400 to 380 years old, anthropologist Joan Brenner Coltrain of the University of Utah in Salt Lake City found that the skulls did indeed separate into these two groups, and that all skulls older than 1000 years were dolichocranic. The groups “appear genetically distinct,” Coltrain says. “Paleo-Aleut [skulls] are typical of the earliest people to occupy the New World, like the Kennewick Man and the Spirit Cave Woman. They all look more European than Asian, perhaps because they descend from European populations that occupied the Siberian region.”

    Recent genetic work confirms the distinction: Mitochondrial DNA (mtDNA) from 69 of Hrdlička's skeletons showed that Neo-Aleuts, like most modern Aleuts, descend from a common ancestor that carried genetic markers known as haplogroup D, according to recent work by University of Utah geneticist Dennis O'Rourke. But most Paleo-Aleuts were members of haplogroup A, as are most groups now living in Arctic North America.

    Island arc.

    The Aleutian archipelago, the world's longest, stretches for 2000 kilometers.

    Hrdlička argued that the Neo-Aleut populations came from the Alaskan mainland and replaced the Paleo-Aleuts. But Coltrain and others have found that the newcomers in fact coexisted with the original settlers. “The long-headed Paleo-Aleuts were still very much around” for several hundred more years, says anthropologist Richard Davis of Bryn Mawr College in Pennsylvania. About two-thirds of living Aleuts belong to haplogroup D and one-third to haplogroup A, according to work by Crawford and his co-workers, and they are presumed to be the result of admixture between Paleos and Neos. Crawford's research with modern Aleuts also suggests that they carry some Paleo-Aleut DNA, because their ancestors branched off from other Arctic peoples about 13,000 years ago—long before they colonized the islands, perhaps when they were still in Asia or Beringia.

    The Neo-Aleuts were not only physically but also culturally distinct. For example, Davis says, after 1000 years ago, the archaeological record reflects a shift to more sophisticated stone tool types as well as changes in house styles from single to multiroomed structures. The Neo-Aleuts ate more big marine mammals such as sea lions and seals, while Paleo-Aleuts dined more on smaller animals such as birds and sea otters, according to an isotopic study of their bones that Coltrain published in the journal Arctic in 2010. “The Neo-Aleuts may have been more sophisticated technologically or more hierarchical in social organization,” Coltrain says, possibly because they came from a “more complex and populous Alaskan peninsula setting.”

    Archaeologists are working all across the islands, and additional burials that might yield more ancient DNA are turning up as climate change accelerates coastal erosion, says archaeologist Debra Corbett of the U.S. Fish and Wildlife Service in Alaska. However, the Aleuts, like other Native American groups, are sometimes hesitant to allow research on skeletons (Science, 8 October 2010, p. 166). “Our policy is that if human remains are found, they must be immediately reburied,” says Melvin Smith, archaeology coordinator for the Anchorage-based Aleut Corp., which represents native interests.

    Nevertheless, Smith, who grew up on two of the islands, says archaeology helps native Aleuts to “better understand our own history and culture.” And sometimes the corporation makes exceptions. For example, in a new edited volume, Corbett and her colleagues report on the 350-year-old remains of a child from one of the central islands, who was a member of haplogroup D like the Neo-Aleuts. Isotopic studies show that the child ate shellfish and sea birds and was infected with roundworms and tape-worms that often contaminate sea mammal meat.

    From east or west?

    Such recent burials offer clues to the lives of the Neo-Aleuts, but what of the ancient Paleo-Aleuts? Where did they come from, and when did they get here? For much of the 20th century, such questions went unanswered, as few researchers reached the remote archipelago. Then in 1942, after the attack on Pearl Harbor, the Japanese invaded the western islands of Attu and Kiska and put the inhabitants in concentration camps in Japan. In response, the Americans built a military base on Adak and evacuated nearly all the Aleuts to abandoned canneries in southeast Alaska. Only a few dozen families subsequently made it back to their native islands. “The Aleuts suffered tremendously,” says archaeologist Dixie West of Kansas State University, Manhattan.

    Bounty from the sea.

    With kayaks, the Aleuts colonized islands and exploited maritime riches, as seen in this 19th century painting by Henry Wood Elliott.

    CREDIT: NATIONAL ANTHROPOLOGICAL ARCHIVES, SMITHSONIAN INSTITUTION [IMAGE 7119_13]

    Investigations into Aleut prehistory came to a standstill. Then after WWII, the islands were caught up in the Cold War. Adak housed up to 6000 soldiers and sailors, and civilian access to the island was limited.

    The old ways.

    Colonization disrupted Aleut culture (seen in painting, left), and WWII forced the children in this 1938 photo to leave their island. But some traditions, such as dancing regalia (right), have been preserved.

    CREDIT: PHOTO BY HULTON ARCHIVE/GETTY IMAGES; V. B. SCHEFFER/LIBRARY OF CONGRESS; LAURA GRABHORN

    Finally, in the late 1990s, the base closed. Although no Aleuts had lived on Adak since the 1800s, some now settled there. Beginning in 1998, Corbett, West, and other archaeologists began to visit, eager to uncover the story of one of the last great peoplings of the world.

    They began to tackle one of the most basic and yet controversial questions about the settling of the Aleutians: Were they colonized from west to east, or the reverse? If they came westward from Alaska, then they must first have crossed the Beringian land bridge to the Americas, making them part of that great migration. But if they came from Russia, then their southerly shortcut across the Bering Sea may have been independent of the larger Beringian migrations.

    Some Russian archaeologists had argued that the first Aleuts entered the archipelago from the west, via the Commander Islands near Russia's Kamchatka Peninsula. (The far-western Commander Islands belong to Russia, while the rest of the Aleutians are U.S. territory.) But American archaeologists pointed out that the earliest known Aleutian archaeological site was radiocarbon-dated to 9000 years ago—and it is located in the east, on Anangula Island.

    To resolve the issue, West, Corbett, and a handful of others began excavations and radiocarbon dating on the islands. They found that the western islands were first occupied about 3500 years ago, relatively late. Then in 2005, dates from radiocarbon and volcanic ash put fish bones on Adak, at site ADK-171 overlooking Clam Lagoon, at nearly 7000 years ago. This demonstrated a clear east-west pattern of migration. “It looks as though the Aleutians were occupied from the east,” agrees paleoecologist Arkady Savinetsky of the A. N. Severtsov Institute of Ecology and Evolution in Moscow.

    Recent genetic studies bolster the archaeological evidence. Despite the fact that few today live in the islands of their grandparents, Aleuts remember where they came from, and their memories have helped create a remarkably sharp portrait of geography and genes. Each island community had distinctive dance regalia, and an Aleut's origins can still be identified from the ceremonial costumes he or she wears today, explains Mike Swetzof, who was born on St. George Island and is now mayor of Adak.

    Crawford's team has now analyzed mtDNA from more than 250 Aleuts from 11 islands as well as displaced Aleuts living in Anchorage and compared them with mtDNA from people elsewhere in the Arctic. The Aleuts bear little genetic resemblance to people of the Kamchatka Peninsula, as might have been expected had the islands been colonized from west to east. And the data show a striking correlation between the island that families originally came from and their maternally inherited mtDNA. “The Aleut populations are distributed spatially like beads on a necklace,” Crawford and his co-workers wrote in 2010 in Human Biology. Indeed, the mtDNA haplogroups can be further subdivided into three groups, corresponding to the eastern, central, and western Aleutians, regions that also differ somewhat in cultural traditions, according to recent archaeological work. “This really blew my mind when you consider everything that has happened to the Aleuts,” Crawford said. “The correlation between genetics and geography was phenomenal.”

    Ripan Malhi of the University of Illinois, Urbana-Champaign, agrees that there is a “very clear pattern from east to west in the mtDNA haplogroup” profiles. But he questions whether that is a relic of migrations that took place as early as 9000 years ago or perhaps reflects more recent movements along the Aleutian chain. (The paternally inherited Y chromosomes don't show such a clear geographic pattern, probably because Russian men had children with Aleut women, researchers agree.)

    Who are the Aleuts' closest relatives today? To date, no one has sequenced the whole genome of an Aleut, although researchers are working on it. But the mtDNA data cluster them with Siberians and the people of Russia's northern Chukchi Peninsula, which was once part of the Bering Strait land bridge. Aleuts show little mtDNA resemblance to Alaskan Eskimos, possibly refuting earlier assumptions that these groups separated relatively late, Crawford says. Comparisons of mtDNA from Aleuts, Eskimos, and Asian groups suggest that the Aleuts and Eskimos originally shared a common ancestor in Asia but went their separate genetic ways at least 11,000 years ago, probably while still in Asia; they may even represent separate migrations. “This suggests that there have been a lot of population expansions out of Beringia” and into the Americas, Malhi says (Science, 23 September 2011, p. 1692). “These populations had a dynamic history of extinction, admixture, and expansion.”

    Colonizing by kayak

    One foggy Thursday last June, a team of archaeologists led by Diane Hanson of the University of Alaska, Anchorage, boarded the 3.5-hour flight to Adak, only to circle the island and turn back to Anchorage because of low visibility. They made it out the following Sunday, then hopped aboard the U.S. Fish and Wildlife Service ship the Tiglax—which provides a ferry service for researchers in the Aleutians—to a remote spot in western Adak, where they camped for 2 months, excavating prehistoric Aleut houses. This latest work, at an inland site, provides new evidence that the versatile ancient Aleuts exploited habitats all over the islands, not just on the coasts.

    But there's no denying the power of the sea in Aleut life. And there's no doubt that whoever came to the Aleutians, and when, must have done it by boat. During glacial times, the easternmost islands were part of Beringia. But the rest of the Aleutians, including Adak, have been in open sea for more than 20,000 years.

    The Aleuts encountered by the Russians were traveling between islands in kayaks and umiaks (larger open boats) made from driftwood or whalebone frames and covered with seal skins. Remains of such boats have been found at numerous Aleutian sites dating back about 2000 years; researchers assume that the first Aleuts had similar boats, although the evidence does not preserve over time. “The fact that we find obsidian on Adak that comes from an island 1000 kilometers to the east indicates that these folks were moving around and they weren't doing this by swimming or walking between the islands,” West says. “Those seas were treacherous.”

    It's no surprise that the Aleutians were colonized after the rest of the Americas: Massive ice sheets blocked the way from the Alaskan peninsula to the Aleutians until about 9000 years ago, according to work in the 1970s. The Paleo-Aleuts “probably could have landed on glacial shores and spent the night,” Johnson says. “But it wasn't a place they could live.” Once the sea route was clear, however, the ancient Aleuts moved swiftly. “The earliest inhabitants we know of, at Anangula, camped virtually right on top of glacial till,” Davis says. “This suggests that as soon as those small islets were clear of ice, hunters from the mainland came to exploit available resources right away.” Indeed, some researchers say, the islands' abundant maritime resources might have provided sustenance as good as or better than that available on the mainland. “The Aleuts became adapted to a kind of life that was quite rich, richer than most of the terrestrial areas,” Dumond says. “As the population grew, it dug itself in to that way of living.”

    Frigid waters.

    Cold-loving cod (inset) hint that the Aleutians were colonized during cold spells.

    CREDITS: MASAYUKI TORII; (INSET) KITTY MECKLENBURG/NOAA

    New evidence suggests that the pulse of migrations from east to west may correlate with times when the sea was coldest and most productive. Three western Aleutian islands were apparently first occupied during a long cold spell that started 3350 years ago, according to a paper by Savinetsky in a 2010 edited volume. In a second volume just published, Savinetsky, West, and others report that about 13% of the fish species at Adak's 7000-year-old ADK-171 site were cold-loving saffron cod. This suggests that Adak, too, was first settled during a cold period.

    Cold periods might also have dampened the wicked winds of the Bering Sea, say Savinetsky and West, who point to earlier work suggesting that cooling in the north Pacific may have occurred during periods of weakened cyclonic activity. “Did cooler temperatures mean weakened cyclonic activity, thus less high waves, and greater marine productivity?” West asks. If so, she says, “then perhaps folks were more likely to explore and find new places.”

    When the ancient Aleuts did go exploring, Crawford says, they probably did so in family groups, splitting off from larger island populations and setting up residence on islands farther west.

    But why did they keep trekking westward, exploring new territory? No one knows for sure. Some researchers chalk it up to human nature—our “constant search for new lands and endless curiosity,” says archaeologist Christine Lefevre of the National Museum of Natural History in Paris. Corbett says she wonders about it all the time. “I was on Adak one cloudless, sunny day. I climbed a mountain where I could look out at the other islands. I imagined all those villages and the people living in them, boats on the water, smoke coming out of the houses. This was really a populated landscape. And yet there was lots of elbow room on the Alaskan peninsula and in the eastern Aleutians. But people still kept aiming for the horizon. They kept moving forward.”

    Additional Reading

  5. MATERIALS RESEARCH SOCIETY’S FALL MEETING AND EXHIBIT

    New Lease for Leftover Light

    1. Robert F. Service

    Researchers reported at the meeting that they've devised polarizing filters made from organic solar cells that recycle some of the absorbed light from liquid crystal displays.

    Solar harvest.

    Light shines through two polarizing filters oriented parallel to each other (above). But most is blocked when one is turned 90 degrees (left).

    CREDITS: YANG YANG LAB/UCLA

    Today's thin TVs and computer monitors have the cool factor, but they're energy hogs. The most common monitors, liquid crystal displays (LCDs), waste about 75% of the backlight they use to light the screen. Most of it is absorbed by polarizing filters that control how much light passes through each point on the screen in order to produce the desired image. Researchers in California reported at the meeting, however, that they've devised polarizing filters made from organic solar cells that recycle some of this absorbed light. With further improvements, energy captured by the new solar cell filters could noticeably improve lifetimes of cell phones, laptops, and other battery-driven technologies that rely heavily on displays.

    LCDs take advantage of the fact that the electromagnetic waves that make up light oscillate in different directions. Unlike waves in the ocean that rise and fall vertically, light waves can oscillate side to side as well. To control what light comes through a screen, LCDs use two polarizing filters. The first blocks all the light waves except those that oscillate up and down, and the other blocks all the light waves except those that oscillate left and right. Virtually all light that encounters both filters is absorbed, and the spot remains black.

    In between these filters sits a layer of liquid crystals, rod-shaped molecules that stack like logs in a pile all oriented in the same direction. When given a jolt of electricity, the rods in the pile twist like a spiral staircase so that the rods at the top of the pile are perpendicular to those at the bottom. This helical twist rotates the polarization of photons of light passing through, allowing them to emerge from the display.

    This technology is more energy-efficient than many rival technologies, but it's still wasteful: In many modern electronic devices, 80% of the total energy they use goes to lighting the display. But researchers led by Yang Yang, a chemist at the University of California, Los Angeles (UCLA), thought they might be able to recapture some of this lost energy, much as the regenerative brakes in a hybrid car reclaim energy to recharge the car's battery. They replaced the two conventional polarizing filters with organic solar cells. At the heart of these cells are rod-shaped polymers made from the most common organic light absorber, known as P3HT. Yang and his colleagues oriented these rods in the same direction in each solar cell by simply brushing them with a soft cloth. They added additional material films to help convert the captured light to electrical charge and shuttle the charges to wires that could be connected to a battery. They then oriented the two solar cells so that their light-absorbing polymers were perpendicular to one another. These polarizers absorbed 90% of the light, converting about 3% of it to electricity, which in a real device would be used to recharge the battery. Even better, the new solar cell filters continue to harvest light even when the LCD screen is not in use. So such displays could serve not only as an energy saver but also as an energy supply. The UCLA results were also reported in the 22 September 2011 issue of Advanced Materials.

    Marc Baldo, an organic solar cell expert at the Massachusetts Institute of Technology in Cambridge, calls the new work “a good thing.” But Baldo and Yang point out that to be useful commercially, organic polarizing filters would need to block more than 99% of the light in order to create black on the screen. “That's an all-around big issue for organics” because organic light absorbers typically don't do a good job of blocking red light. But at the meeting, Yang reported that his group has developed a novel polymer that absorbs red and infrared light. The group is currently using it to make solar cells. Yang notes that if the new IR polymer pans out, it might improve not only future displays but also plastic solar cells in general. Because the polymers absorb IR light but let visible light pass through them, they could be layered atop conventional visible light-absorbing cells to boost the amount of light captured and converted to electricity. That could add an extra cool factor to solar cells as well.

  6. MATERIALS RESEARCH SOCIETY’S FALL MEETING AND EXHIBIT

    Snapshots From the Meeting

    1. Robert F. Service

    Snapshots from the meeting include organic photovoltaics that break the 10% barrier, heat-stable stretchable electronics, a nanowire-based optical probe that can peer within individual cells, large-scale nanocarbons, and a light-sensitive protein that can turn a transistor on and off.

    Organic PVs break the 10% barrier. Researchers from Mitsubishi Chemical Group Science and Technology Research Center in Yokohama, Japan, reported that they've created the first organic photovoltaic device that's more than 10% efficient at converting sunlight to electricity, but they offered few details on the new device.

    Stretchable electronics beat the heat. Researchers would love to use flexible organic-based integrated circuits (ICs) as implantable electronics for sensors and other health-monitoring devices. But they've had trouble making them robust enough to withstand the high temperatures needed to sterilize them. At the meeting, a team from the University of Tokyo reported that it has now created heat-stable organic ICs.

    Lookie here. Researchers at the University of California, Berkeley, have created a new nanowire-based optical probe able to peer within individual cells.

    Large-scale nanocarbons. Researchers in Japan reported that a new pilot-scale production plant is producing 100 grams of carbon nanotubes per hour and said they're on track to open a commercial-scale facility in 2014 capable of producing 50 tons per year. Another team, meanwhile, reported being able to synthesize single-atom-thick carbon sheets of graphene in a roll-to-roll setup like those used in printing.

    Can you see me now? Researchers in California reported using a light-sensitive protein to turn a transistor on and off. The proteins in this case were ion channels able to ferry protons from one side of a cell membrane to another when exposed to light. They were embedded in a lipid coating around a nanowire electrode in the device; when light hit the proteins, they pumped protons away from the nanowire, thereby changing the pH nearby and triggering the transistor to turn on. Down the road, arrays of such devices might be used to make an artificial retina.

  7. MATERIALS RESEARCH SOCIETY’S FALL MEETING AND EXHIBIT

    Al Bids to Vie With Li in Battery Wars

    1. Robert F. Service

    At the meeting, researchers described materials that could pave the way for making rechargeable batteries from aluminum, which could lead to cheaper and safer rechargeables.

    We love our rechargeable lithium-ion batteries. They drive our cell phones, laptops, power tools, electric cars, and countless other gadgets. And their numbers are rising. The global market for lithium-ion batteries has risen five-fold to $10 billion a year over the past decade. Still, lithium-ion batteries may face tough times ahead. Lithium supplies are limited, and the cost of the metal has skyrocketed in recent years. So researchers are on the lookout for novel battery chemistries. At the meeting, researchers from New York described materials that could pave the way for making rechargeable batteries from aluminum. Because aluminum is one of the most abundant elements on the planet, and is less prone to catching fire than lithium is, it could pave the way to cheaper and safer rechargeables.

    Batteries work by shuttling ions back and forth through an electrolyte that sits between two electrodes. At the electrodes, the ions either give away extra electrons during discharge or sop them up during recharging. Numerous researchers have dabbled in making aluminum batteries before. But aluminum ions are larger than lithium ions, and they tend to clump together inside batteries. These aluminum clumps move more slowly between electrodes than lithium ions do, which reduces their conductivity. So in the past, research teams ran their aluminum-ion cells at high temperatures to boost their conductivity. But high-temperature cells aren't useful for most applications that run at or near room temperature.

    Cheaper rechargeables?

    New aluminum-ion batteries store about the same amount of energy as lithium-ion versions, and they should be safer.

    CREDIT: ADAPTED FROM L. ARCHER/CORNELL UNIVERSITY

    In 2010, researchers at Cornell University, led by chemical engineer Lynden Archer, began searching for a way to boost the room-temperature conductivity of aluminum-ion cells. Previous aluminum-ion batteries had used conventional ion-conducting electrolytes, which were poor aluminum-ion conductors. So Archer and his colleagues turned to an electrolyte made from an ionic liquid that sped up the shuttle time for the aluminum ions. They also synthesized vanadium-oxide nanowires for their cathode that were able to harbor more aluminum ions during charging. At the meeting, Archer's postdoctoral assistant Navaneedhakrishnan Jayaprakash reported that the new cells made with these improvements were rechargeable at room temperature at typical recharge times. After 20 charge-discharge cycles, they had a capacity of 273 milliamp-hours per gram, on par with lithium-ion cells sold today. The results were also published online on 3 November in Chemical Communications.

    “It's quite intriguing,” says Paul Braun, a chemist and battery expert at the University of Illinois, Urbana-Champaign. One advantage, Braun says, is that each aluminum ion can ferry three electrons every time it moves between electrodes, whereas lithium ions can carry only one electron. That could help boost the energy-storage capacity of aluminum batteries. But both Braun and Archer note that the new aluminum-ion cells aren't ready to go up against lithium cells. The ionic liquid electrolyte is too expensive for commercial use. And the anode in the new battery is pure aluminum metal, which after repeated charge-discharge cycles can form tiny metal spears that can damage key parts of the battery. Archer says he and his colleagues are now turning to these and other challenges in hopes of turning one of the most abundant metals into a better battery.

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