Random Samples

Science  10 Feb 2006:
Vol. 311, Issue 5762, pp. 753

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    This golden-mantled tree kangaroo, killed by indigenous subsistence hunters, was one of the surprise finds from a biodiversity survey conducted in December on the western, or Indonesian, half of New Guinea. The species was thought to inhabit only a single area in eastern New Guinea and had only been recorded once before by scientists, in 1988, says Bruce Beehler of Conservation International (CI) in Washington, D.C.

    The “rapid assessment survey” by CI scientists was the first attempt to document flora and fauna in the Foja Mountains' vast tract of unspoiled rainforest. The group cataloged an array of treasures, including a new honeyeater, a “lost” bird of paradise, dozens of new frog and butterfly species, and giant rhododendrons.



    The fingerprints below are from an Argentinian murderer, Francisca Rojas, who in 1892 became the first person to be convicted based on such evidence. The card is part of a new exhibit, “Visible Proofs,” tracing the history of forensics that will open on 17 February at the National Library of Medicine in Bethesda, Maryland. Among its curiosities are the instruments used for President Lincoln's autopsy, a human heart pierced by a bullet, early medical treatises, and film clips of autopsies. More leisure, less time.


    More leisure, less time.CREDIT: ROYALTY FREE/CORBIS

    Americans may always be complaining about having too much to do, but the fact is they have enjoyed a phenomenal increase in leisure time over the past 40 years, according to two economists.

    Based on surveys of self-reported time use through the decades, Erik Hurst of the University of Chicago reported last week that those in the U.S. job market had 6 to 8 hours more leisure time per week in 2003 than they did in 1965. Total hours devoted to leisure in the narrowest sense—activities pursued solely for enjoyment—rose from 31.04 to 35.65 a week. Speaking at the American Enterprise Institute in Washington, D.C., Hurst also said that although 74% of women were in the job market in 2003—compared with 48% in 1965—leisure time for both men and women in the 21-to-65 age range had increased “dramatically.”

    While hours worked per week have remained stable, there's been a huge time savings—about 12 hours a week—in housework, according to Hurst. TV watching is devouring two-thirds of the time gained, while time spent reading and churchgoing is down.

    Economist Valerie Ramey of the University of California, San Diego, who reported on data from the entire U.S. population, said that there's a “higher fraction of harried people now,” which may have led to a “myth” that people are working more. In reality, “we're doing more things,” she said. Both economists predicted that leisure time will continue to increase, because people are living longer and have fewer children to care for.



    An unusual study of old skulls has revealed that human heads have gotten significantly bigger than they were just a few centuries ago.

    Led by orthodontist Peter Rock of the University of Birmingham, U.K., researchers measured 30 skulls from male and female victims of London's Black Death epidemic of 1348-'49 and 54 male skulls brought up from a warship, the Mary Rose, which sank in England's Portsmouth harbor in 1545. The team compared the old skulls with x-rays from 31 modern young adults of both sexes. The height of the modern group's cranial vaults exceeded that of both historic samples by about 15%, the team reported last month in the British Dental Journal. Although it is well known that body size has increased over the centuries as diets have improved, Rock says he found hints that brain size might have increased independently: Faces have become less prominent in relation to foreheads over the centuries, he says, and the part of the skull that holds the brain's frontal lobes—the part associated with intelligence—was proportionally larger in modern skulls.

    “I think it's a very exciting study because they have two very interesting samples from the past,” says primatologist Robert Martin of the Field Museum in Chicago. But the significance of the brain change can't be determined, especially because there are no bones available to reveal the relationship to body size.