Science Confirms the Obvious

It takes real proof to back up even the simplest theories--these 10 studies show that the obvious can have not-so-obvious implications

Sometimes it takes long, hard study to pin down what we thought we knew all along—and to reveal surprising findings beneath the surface of common sense. Ducks like water? Gamblers don't learn from their mistakes? Shocking!

Launch the gallery for our latest roundup of bafflingly obvious studies from the world of science.

And for much more, see our Science Confirms the Obvious posts archived here and our previous Science Confirms the Obvious roundups from the magazine here and here.

Gamblers Don't Learn From Their Mistakes

The Study "Executive Function Abnormalities in Pathological Gamblers,a€_ Clinical Practice and Epidemiology in Mental Health,_ March 2008 The Findings A trip through Las Vegas will reveal plenty of two-time (and 20- and 100-time) losers who haven't learned when to walk away. Although scientists suspect that a mix of genetic and environmental factors causes compulsive gambling, they haven't pinned down what's going on in an addict's mind that keeps him at the table. Researchers at the University of Pisa in Italy put 20 diagnosed compulsive gamblers through several tests, including a card-sorting exercise. The gamblers displayed normal verbal and memory skills but had difficulty solving problems and took longer than average to learn from their mistakes or look for alternative solutions. Instead of changing strategies, the persistent gamblers showed signs of a€œcognitive rigiditya€ and repeatedly tried ineffective solutions. Why Bother? The goal is to find a cure for compulsive gambling, and although the sample group is small, this study suggests that a root cause might be abnormalities in the prefrontal lobea€”the gamblers' problems were similar to those of people who had suffered minor brain damage. It's not a cure, but neurologists now at least know where to poke and prod.Tom Nick Cocotos

Potato Chips are Bad for You

The Study a€œChronic Intake of Potato Chips in Humans Increases the Production of Reactive Oxygen Radicals by Leukocytes and Increases Plasma Ca€“Reactive Protein: A Pilot Study,a€_ The American Journal of Clinical Nutrition,_ March 2009 The Findings For four weeks, researchers at the National Institute of Food and Nutrition in Warsaw, Poland, and others fed 14 healthy men and women 5.6 ounces of potato chips each daya€”roughly half a family-sized bag. They monitored the effects of acrylamide, a compound that forms while cooking certain starchy foods like chips and fries. After 28 days, the subjects had higher acrylamide levels and related inflammation that can lead to atherosclerosis, a cardiovascular disease involving hardening of the arteries. Why Bother? Acrylamide was first detected in junk foods in 2002, and it could be a menace on the order of trans fats. The researchers say their study a€œindicates that high-acrylamide ingestion may constitute a new dietary risk factor for atherosclerosis progression, both in a healthy population and in patients with coronary artery disease.a€Tom Nick Cocotos

People Binge-Drink on their 21st Birthday

The Study a€œ21st Birthday Drinking: Extremely Extreme,a€_ Journal of Consulting and Clinical Psychology,_ June 2008 The Findings Researchers at the University of Missouri wanted to determine just how crazy things get on a person's first booze-legal birthday. They interviewed more than 2,500 college students and found, among other things, that half of birthday drinkers drank more than they ever had before. Some 49 percent of birthday boys and 35 percent of birthday girls reached a blood-alcohol level of 0.26 percent, which can lead to unconsciousness and vomiting. Fully 12 percent went a€œ21 for 21a€a€”that's 21 drinks in one night. Why Bother? The study takes on a tradition that contributes to the 1,400 alcohol-poisoning-related deaths in college-age kids per year. Led by alcohol researcher Kenneth Sher, who says that a€œextreme bingeing can rapidly lead to brain damage,a€ it concludes, a€œit is imperative that we acknowledge the danger."Tom Nick Cocotos

Girls Like Pink

The Study a€œBiological Components of Sex Differences in Color Preference,a€_ Current Biology,_ August 2007 The Findings Studies have shown that both genders like the color blue, but science has never proven that girls like pink. Then Anya C. Hurlbert and Yazhu Ling of Newcastle University in England devised a rapid, a€œforced-choicea€ test in which subjects view color choices on a computer display and must instinctively decide which shade they prefer. It turns out that while blue and green hues have universal appeal, men hate pink, and women love it. Why Bother? The study's authors hope it will shed light on human evolution. Hunter-gatherer women may have developed an eye for red hues to help find ripe fruit or to discern a€œsubtle changes in skin color due to emotional states and social-sexual signals,a€ which would help them spot potential mates and facilitate social interaction.Tom Nick Cocotos

Husbands Create More Housework

The Study _ Panel Study of Income Dynamics (ongoing), Institute for Social Research_ The Findings The University of Michigan's panel study, which has been tracking income and demographic changes since 1968, analyzed the number of hours men and women spent on housework. On average, married women did seven more hours of weekly housework than single gals. For men, however, having a wife reduced housework by one hour compared with their bachelor buddies. Why Bother? While the top-level findings make husbands sound like a raw deal, it turns out marriage is getting easier for the modern woman. According to the PSID, in 1976 women spent 26 hours a week on housework compared with 17 in 2005. Men had it easy in '76, clocking six hours. In 2005 they were doing chores 13 hours a week, meaning they were almost pulling their weight around the house. Economist Frank Stafford, who directs the study, notes that demographics skew the results: Husbands tend to work outside the house, while wivesa€”especially mothersa€”are more often at home.Tom Nick Cocotos

Scrawny or Fat Boys Don't Like Gym Class

The Study a€œHealthy Bodies, Boys, and Body Image,a€_ Ongoing three-year study_ The Findings Michael Kehler, an associate professor of education at the University of Western Ontario, is conducting interviews, observing gym classes, and monitoring blogs created for the study to figure out if there is a correlation among Canadian boys between poor body image and opting out of gym class. So far, his study has found that underweight, overweight and uncoordinated boys tend to avoid the bravado and humiliation of dodgeball any way they can. Why Bother? Kehler points out that gym can be traumatizing. Skipping it might be an early sign of trouble in boys, creating habits that can lead to obesity or social isolation, and educators need to account for that potential. a€œThe long-term health impact of the experiences... significantly contributes to participation in healthy practices later in life,a€ he says.Tom Nick Cocotos

Ducks Like Water

The Study a€œWater Off a Duck's Back: Showers and Troughs Match Ponds for Improving Duck Welfare,a€_ Applied Animal Behavioral Science,_ July 2008 The Findings Everyone knows that ducks enjoy a dip, but the 18 million meat ducks reared in Great Britain have no legal guarantee of even a puddle. During a three-year study, researchers at the University of Oxford's department of zoology set out to discover how access to water affects the health of commercial quackers. The outcome? Ducks with access to a clean bath were tidier than those without, although many ducks preferred a shower. Why Bother? Baths, it turns out, are a bad idea. a€œCommercial duck producers would very much like to provide ducks with bathing water, buta€”and this is what is so often misunderstooda€”doing so brings health and welfare problems with it,a€ wrote one of the researchers, Marian Stamp Dawkins, after her study was ridiculed by British papers. Stagnant ponds can lead to bacterial and fecal contamination that can work its way up the food chain. Showers are better for the fowl and their keepers. a€œTheir health was good,a€ Dawkins writes, a€œand they spend even more time in showers...when given the choice.a€Tom Nick Cocotos

Faceshields Protect the Face

The Study a€œOptical Quality and Impact Resistance Comparisons of Two Football Helmet Faceshields,a€_ Optometry: Journal of the American Optometric Association,_ August 2008 The Findings The American Academies of Ophthalmology and Pediatrics recommend that football players wear Plexiglas face shields in their helmets to help prevent some of the 2,200 eye injuries players suffer every year. But the shields have no regulated performance standards. So researchers at Ohio State University and elsewhere took Oakley- and Nike-brand shields and smashed baseballs into them at 148 miles an hour, simulating the force of an elbow or a placekick, to see if the shields would shatter or reduce visibility. The verdict? Both models took their lickings like champs. Why Bother? Although new masks did well, used masks tended to shatter or lose visibility. Aaron Zimmerman, one of the researchers at the Ohio State University College of Optometry, hopes this study will help set a standard. a€œWe now know that polycarbonate breaks down with light exposure and impact,a€ he explains. a€œThat's why this study needed to be done.a€Dirk Hansen

Toothpaste is a Luxury in Poor Countries

The Study a€œGlobal Affordability of Fluoride Toothpaste,a€_ Globalization and Health,_ June 2008 The Findings Tooth decay is the world's most common noncommunicable disease, and as Western diets proliferate, teeth are getting worse. A panel of public-health researchers from the World Health Organization and others studied the affordability of fluoride toothpaste. They found that in the U.K. it takes 0.02 percent of a family's annual household budget to buy enough toothpaste for the year, while in Zambia it takes far morea€”4 percent. Why Bother? Tooth decay is a winnable public-health problem. The researchers suggest tax breaks, producing toothpaste locally, and reducing packaging to bring down costs and get more people brushing. The study points out that cavity-related childhood malnutrition and infection can impair mental and physical development and a€œsince the poor are most vulnerable to the impacts of illness, they should be afforded a greater degree of protection.a€Mauren Veras

Violence Occurs Near Bars and Liquor Stores

The Study a€œA Longitudinal Analysis of Alcohol Outlet Density and Assault,a€_ Alcoholism: Clinical and Experimental Research,_ June 2008 The Findings This study by Michael Livingston, a research fellow at the AER Centre for Alcohol Research near Melbourne, Australia, analyzed nine years of the connection between locations issued liquor licenses and the incidence of alcohol-related violence in his city. He found that suburban alcohol-related violence happened near liquor stores, while bars and clubs led to trouble in the city. Why Bother? Livingston says that because the patterns are different in cities and in the a€˜burbs, a€œthere is a need for greater control over the proliferation of alcohol outlets across a wide range of communities.a€ Municipalities should pay attention to the liquor licenses they issue, and particularly to whether the outlet in question is in an urban or suburban area. Cities could perhaps spread the clubs and bars around a bit to ward off fights, while surrounding towns might want to put some driving time between liquor stores.Harry Heng