Health & Science

Intelligence to crow about

In fact and in legend, crows are extremely clever. One of Aesop’s fables tells the tale of a thirsty crow who cannot reach the water in a half-filled pitcher. The bird solves his problem by dropping stones into the pitcher until he displaces enough fluid that the water rises to the top, where he can take a sip. British researchers have proved Aesop wasn’t just telling tales, says the Los Angeles Times. The researchers set up four rooks—members of the crow family—with some pebbles and an upright tube; the tube held a small amount of water on which a wax worm floated. The rooks immediately figured out what to do: By dropping in stones, they raised the water level until they could reach the worm. More impressive still is the fact that the birds quickly learned to select larger stones because they displace more water than smaller ones. And the crows waited to dip in their beaks until they’d dropped in enough stones, “as if they were estimating the number of stones they needed right from the start,” said researcher Nathan Emery of Queen Mary, University of London. The only animal with a remotely similar skill set is the orangutan, and its brain is far bigger. The study is “remarkable,” primatologist Frans de Waal says, as it shows rooks to be spontaneous problem solvers.

Where clouds begin

Subscribe to The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

SUBSCRIBE & SAVE

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Sign up

Clouds are as common as day, but scientists don’t fully understand how they form. One theory is that water molecules attach to floating particles of pollen or dust, and then gather by the trillions to form clouds. But a prominent Danish physicist suggests that clouds may actually have their origin in outer space. Henrik Svensmark argues that water molecules in Earth’s atmosphere are stripped of their electrons by cosmic rays—fast-moving atomic particles from deep space—and turned into electrically charged ions. Like little magnets, these ions then attract other water molecules and eventually form clouds. Three years ago, Svensmark demonstrated the effect in the lab; recently he bolstered his case by analyzing 22 years of weather-satellite data. Svensmark found that Earth’s cloud cover dropped significantly during certain solar storms, when the sun blasts a wave of superhot particles at Earth and temporarily shields the planet from cloud-forming cosmic rays. The finding is “astonishing,” Norwegian geoscientist Jón Egill Kristjánsson, who has pursued similar research for years, tells ScienceNOW. If other observations back them up, “Svensmark’s new results would greatly strengthen the case for a cosmic ray–

cloud connection.’’

Gays can’t be ‘converted’

Can gays and lesbians willfully change their sexual orientation? A few organizations, often founded by religious conservatives, contend that so-called reparative therapy can indeed help gays go straight. But after examining more than 80 studies on sexual orientation change, the American Psychological Association concluded that the treatments didn’t work and urged psychologists to steer gay clients away from them. At best, “certain studies suggested that some individuals learned how to ignore or not act on their homosexual attractions,” Judith Glassgold, who led the group’s investigatory panel, tells CNN.com. At worst, the treatments backfire, leaving patients depressed, filled with self-loathing, and even considering suicide. But at the same time, the APA said, therapists cannot just disregard patients’ religious faith. To reduce the conflict between their sexual orientation and spiritual outlook, therapists can suggest alternatives to gay patients, such as embracing celibacy or finding a church that welcomes homosexuals. “Secular therapists have to recognize that some people will choose their faith over their sexuality,” Glassgold says.

Long live optimism

If you look on the bright side, you’re more likely to live longer than pessimists, a new study says. University of Pittsburgh researcher Hilary Tindle surveyed nearly 100,000 women, ages 50 to 79, about their outlook on life, then tracked their health for several years. Women who answered yes when asked such questions as, “In unclear times, I usually expect the best” were categorized as optimists; pessimists were those who affirmatively answered questions such as, “If something can go wrong for me, it will.” All were healthy at the start of the study. After eight years, the most optimistic women were 9 percent less likely to have developed heart disease, 30 percent less likely to have died of heart disease, and 14 percent less likely to have died of any cause. Women who scored high in “cynical hostility” were at even greater risk of dying in general. “When you look at all of the risks, pessimists had everything in the wrong direction,” Tindle tells CNN.com. “The question is, can we take these ingrained attitudes and teach that individual to modify them?