More on TV Violence
An unusual longitudinal study has strengthened the case that children who watch violent TV become more aggressive adults, but agreement is still elusive on this long-smoldering issue.
L. Rowell Huesmann and colleagues at the University of Michigan, Ann Arbor, studied 557 young Chicago children in the 1970s and found that over a 3-year period their TV habits predicted childhood aggression. Now they've done a 15-year follow-up on 329 of their subjects. In this month's issue of Developmental Psychology, they report that people who watched violent shows at age 8 were more aggressive in their 20s. Men who had been in the top 20% of violent TV watchers as children were twice as likely to push their wives around; women viewers were more likely to have thrown something at their husbands. The differences persisted, the researchers say, even when they controlled for children's initial aggression levels, IQs, social status, and bad parenting. Study co-author Leonard Eron thinks the association is now airtight—“just as much as smoking causes lung cancer.”
Some researchers agree. The study “shows more clearly than any other that TV is more than just an amplifying factor: It alone can cause increases in aggression,” says Duke University biologist Peter Klopfer. But skeptics remain unconvinced. “We already know that exposure to media violence is associated with aggressive behavior,” says biostatistician Richard Hockey of Mater Hospital in Brisbane, Australia. And the most plausible explanation is still that “aggressive people like violent TV.” Hockey adds that if causation exists, the effect is modest: Correlations of childhood violent TV viewing with adult aggression hover around 0.2, which means that TV contributes just about 5% of the increase in aggressive behavior.
Messing With a Shrimp's Head
Many parasites have life cycles that involve hopping from one host to another. A Toxoplasma parasite, for example, can make its rat host unafraid of cat odors, making it easier to get to its final feline host. Now researchers think they've figured out how another parasite makes the leap from a shrimp to a bird.
The sand shrimp, Gammarus insensibilis, is one host of a parasitic fluke, Microphallus papillorobustus. Normally, the crustacean tries to evade predatory birds by turning away from the sun and diving into the water, note parasitologists Frederic Thomas of the University of Marseilles in France and Simone Helluy of Wellesley College in Massachusetts. But in parasitized shrimp, the escape reflex appears to be reversed, sending it toward the light, where birds can see it more easily.
To understand how the parasite short-circuits the shrimp's behavior, the researchers used a dye that binds to the neurochemical serotonin. In the 22 March issue of the Proceedings of the Royal Society of London, they report that parasitized shrimp had damaged serotonin-producing neurons. And serotonin levels in their brains' visual centers dropped by 62%.
The study is one of the first to document how parasites alter host behavior through sophisticated changes to brain chemistry, Thomas says. And Joanne Webster, a parasitologist at the University of Oxford, U.K., calls the study “very nice … particularly for explaining” a mechanism—altered serotonin levels—that many parasites may use to manipulate their hosts.
Berlin Builds Frogways
Every spring, people around Germany build little fences to funnel migrating frogs into buckets so they can be carried safely across busy highways to their spawning grounds. Now Berliners plan to build little tunnels so frogs can cross one of their main roads in peace. Construction started last week on a low wall that will guide frogs into 12 tunnels—to fit anything up to the size of a fox—under the heavily traveled Schönerlinder Strasse.
The Berlin taxpayer association opposes the $450,000 project. “It seems inappropriate to spend so much money for a safe toad path at a time when Germany is facing the financial abyss,” says association president Günther Brinker. But Naturschutzbund Deutschland, the nongovernmental organization in charge of the project, says the road lies in a nature preserve and that the money comes from funds earmarked for environmental protection. Once completed, the tunnels will channel 3000 amphibians to safety every spring.
Designer Baby a Chimera?
“The Achilles' heel of genetic enhancement will be the rarity of single genes with consistent effects on complex traits like intelligence and personality. … We haven't even found one [in] schizophrenia, where a simple genetic defect is at least plausible. …
“What's more, even the effects of an entire genome are at best probabilistic, as we see in the [differences between] identical twins. … Neural development is a staggeringly complex process. … There is an enormous and generally unacknowledged role of chance in the development of a human being.”
MIT cognitive scientist Steven Pinker talking about “Human Nature and Its Future” at the 6 March meeting of the President's Council on Bioethics Arlington, Virginia
Science Goes Sailing
As a soccer and tennis player growing up in Sweden, polymer scientist Jan-Anders Manson admits that sports often took precedence over his studies. But as project leader of a Swiss university team that helped design and test a boat that this month captured sailing's most prestigious prize, Manson doesn't have to choose.
“Sports is a fantastic vehicle to transmit basic knowledge to students,” says Manson, who works at the Swiss Federal Institute of Technology (EPFL) in Lausanne. He led a group of 15 institute professors and 20 students who partnered with Swiss billionaire Ernesto Bertarelli and skipper Russell Coutts as their boat, Alinghi, wrested the America's Cup away from Team New Zealand in a series of races off Auckland. “I was inspired by space exploration,” says the 51-year-old Manson, who worked with Boeing Co. in Seattle, Washington, before coming to EPFL. “But quality of life is what's important to today's generation, and sports is a part of that.”
So is speed. The Alinghi partnership demanded answers in a matter of hours from scientists accustomed to spending months on a problem. “We would be given a CAD [computer-aided design] of a new boat shape or new components at 8 a.m. [which was 8 p.m. in Auckland],” explains EPFL mathematician Alfio Quarteroni, who led the modeling and computing team, and by the end of the day his team had rendered a geometric description, solved a complicated series of equations, analyzed the results, and shipped its findings back to New Zealand in time for the next day's sea trials.
Stefan Casticas, EPFL's vice president for research, says the free publicity has been invaluable. “The only thing better would have been putting our logo on the boat,” he jokes. And Manton is eager to help Alinghi defend its title in 2007, should Bertarelli come calling. “It was very rewarding,” says Manton, “and a lot of fun.”
STAR pupil. Her doctoral work is in ecology, but Cornell's Gretchen Gettel is also learning an important lesson in U.S. civics. Thanks to efforts by Gettel and others, the Environmental Protection Agency (EPA) has resurrected its Science to Achieve Results (STAR) fellowship program.
The $10 million program, which typically supports about 110 graduate students a year, was zeroed out in President Bush's 2003 budget request (Science, 29 March 2002, p. 2345), dashing the hopes of Gettel and many other applicants who had received top marks from reviewers. Students at Cornell helped lead a nationwide lobbying campaign that convinced Congress to put back the full $10 million in the EPA budget approved last month. “I was really excited to see democracy working,” says Gettel, who says the victory is “bittersweet”: She may now be too close to finishing her degree to qualify for the fellowship.
The right chemistry. After a 28-year stint as a researcher at Bell Labs, chemist Mark J. Cardillo has retired from industry to head up the $120 million Camille and Henry Dreyfus Foundation, a nonprofit that supports research in the chemical sciences. The 59-year-old Cardillo, who was director of Bell Labs' Broadband Access Research division, says the “humanistic goals” of the New York City-based foundation will be a nice change from profit-oriented industrial research. Cardillo succeeds Robert Lichter, who retired after leading the 57-year-old foundation for 14 years.
Industrial strength. Michel Spiro, the new director of France's National Institute of Nuclear and Particle Physics, wants his scientists to do a better job of sharing their “unique know-how” with industry. The government provides three-quarters of the institute's $55-million-a-year basic research budget, spent at 20 university-based labs around the country. But Spiro, a 57-year-old particle physicist, believes that companies are missing a golden opportunity to tap the institute's particle accelerators and other facilities to solve more applied problems.
At The Movies
Core issues. Geophysicist J. Marvin Herndon hopes that a new science-fiction thriller, The Core, will draw attention to his long-unsung theory that Earth's center is molten uranium. The 58-year-old Herndon offered to be an unpaid consultant after seeing a trailer for the movie last year, and he participated in its final editing. In the film, to be released 28 March, Earth comes close to doom when its core stops spinning, causing its geomagnetic field to collapse. Herndon says his theory, which so far has fallen on mostly deaf ears among scientists, forecasts a similar scenario, although from a burnout of the radioactive fuel inside Earth. “The makers of the movie had a much better attitude towards science than many scientists I know,” says Herndon, whose most recent salvo appears in the 3 March issue of the Proceedings of the National Academy of Sciences.