Random Samples

Science  04 Jan 2008:
Vol. 319, Issue 5859, pp. 15

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    The Tunguska explosion, which in June 1908 leveled trees over a 5000-square-kilometer swath of Siberian forest, may have come from a much smaller meteorite than scientists had thought. A supercomputer simulation by scientists at Sandia National Laboratory in Albuquerque, New Mexico, showed that a much higher proportion of the total blast energy was transported to the surface than had been assumed. As a result, the team reported at last month's meeting of the American Geophysical Union in San Francisco, California, the explosion was likely between 3 and 5 megatons instead of the 10 to 20 megatons estimated earlier. Principal investigator Mark Boslough says the results suggest that small meteorites pose a greater threat to Earth than experts believed.


    Disgraced stem cell scientist Woo-Suk Hwang is seeking to restart his human cloning research in South Korea.

    No one in South Korea has worked in the field since Hwang was dismissed from Seoul National University in March 2006. But on 17 December, the Ministry of Health and Welfare announced that the Suam Biotechnology Institute outside Seoul has applied for permission to begin studies on cloning human embryos for research. Hwang is on the eight-member team but is not the principal investigator.

    Suam received approval from the ministry in September as a “designated institute” qualifying to do human nuclear-transfer studies. Under the recently strengthened bioethics laws, women may not donate eggs directly; scientists have to use leftover eggs from fertility clinics. Hwang, still on trial for alleged embezzlement, bioethics violations, and fraud, began research on animal cloning at Suam in July 2006. He has recently been doing human-cloning research at a lab in Thailand.

    “We're not sure if we will allow such research, in light of recent discoveries of more ethically safe alternatives and Hwang's reputation,” said Byung-guk Yang, head of the ministry's bioethics safety department. The ministry must decide within 90 days of receiving the application.



    Archaeologists have identified what they think are the remnants of a bag of tools used by a Natufian about 13,000 years ago for both hunting and harvesting.

    Natufians were sedentary hunter-gatherer people who are of intense interest to archaeologists because they lived in the Mideast when people first started farming.

    Phillip C. Edwards of La Trobe University in Victoria, Australia, who led excavations of the site—Wadi Hammeh 27—in the 1980s, reported in the December issue of Antiquity that a cluster of artifacts found there was probably all part of one Natufian's gear. The centerpiece was a sickle made of goat horn for cutting wild grains, with grooves in which sharp pieces of flint had been laid end to end like razorblades. There was also part of a bone handle, five beads made from gazelle foot bones, seven polished pebbles, 21 small flint crescent-shaped projectile points, and a core of the same flint.

    The assemblage indicates that one person would set out for the day carrying materials for hunting, reaping, and toolmaking—evidence, Edwards says, that both sexes might have engaged in both hunting and gathering. “Natufian society was going through a profound change that encompassed every aspect of human life,” says archaeologist Anna Belfer-Cohen of Hebrew University in Jerusalem, who agrees that probably included “gender role[s] and division of labor.” Harvard University archaeologist Ofer Bar-Yosef calls the work a “major contribution to what we want to know about Natufian culture.”


    Surfer Mike Ehlon found a chunk of beeswax in 2005.CREDIT: RICK ROGERS/THE BEESWAX WRECK PROJECT

    For the past 300 years, chunks of amber-colored beeswax, some reportedly weighing as much as 54 kilograms, have occasionally washed up on the shores of Oregon's Nehalem Bay after a storm. In a few instances, exceptionally low tides have revealed a wooden hull. But the “beeswax wreck” has long been shrouded in mystery.

    Now, a team of archaeologists, geologists, and historians intends to find the ship and excavate it. From radiocarbon dates of some of the wax and analyses of pieces of Chinese porcelain that have also washed up, they believe the vessel was a Spanish galleon that sank between 1650 and 1700 while plying the historic Manila-Acapulco trade route. Project leader Scott Williams of Washington state's Department of Archaeology and Historic Preservation says beeswax was a big trade item at the time, as the Catholic Church used only that substance for its candles. Because the New World lacked native honey bees, merchants shipped tons of wax made by bees in the Philippines.

    Team members are now using remote sensing to look for the hull of the ship, which they believe is either the Santo Christo de Burgos, which sank in 1693, or the San Francisco Xavier, which disappeared in 1705. Progress is being tracked at http://www.archaeologychannel.org/. Jon Erlandson, director of the University of Oregon Museum of Natural and Cultural History, notes approvingly that instead of wanting to ransack Spanish galleons for gold, this team wants “to really scientifically explore it.”