Don’t know much about…

Over the past two decades, science literacy — an estimate of the share of adults who can follow complex science issues and maybe even render an informed opinion on them — has nearly tripled in the United States. To a meager 28 percent.

U.S. adults had to answer such questions as What is a stem cell? What is an experiment?  True or false: Nuclear power plants contribute to the destruction of Earth’s ozone layer. To be deemed literate, people had to get at least 70 percent of the answers right, explained Jon Miller of Michigan State University in East Lansing.

The new U.S. rate, which he reported February 21, is based on questionnaires administered in 2008. Sweden, the only European nation to exceed U.S. science literacy, ranked seven percentage points higher on a 2005 survey. The U.S. figure exceeds slightly the 2005 science literacy in Denmark, Finland, Norway and the Netherlands and is double the rate in the United Kingdom.

U.S. improvements do not reflect better pre-college science education, Miller contends, since scores on tests of kids’ science achievement have remained stable — and low. A better explanation, he says, is the undergraduate curriculum.

“The United States is the only country in the world, right now, that requires all of its university students take a year of general education,” Miller said, “which means they all have a year of science.” Successful learning also has to do with expectations, he maintains. And unlike in U.S. high schools, college professors insist students learn — or fail them.

Science literacy may also climb as adults encounter relevant issues, said sociologist Jeong-Ro Yoon of the Korea Advanced Institute of Science and Technology in Daejeon. Farmers may take notice, for example, if a genetically modified crop was suddenly slated to be planted upwind of their fields.

Miller concedes that some of the rapid increase in U.S. science literacy may reflect such self-education by adults, aided by the Internet. For instance, as soon as a loved one develops cancer, he noted, parents or spouses often immerse themselves in anything and everything available on likely causes of the disease and treatment options.