According to a survey conducted in 2009 by the Pew Research Center for the People & the Press in collaboration with the American Association for the Advancement of Science (AAAS), only 32 percent of Americans think that evolution causes change, and about half (49 percent) think that Earth is getting warmer because of human activity. Less than half (46 percent) know that electrons are smaller than atoms, and 52 percent know that stem cells can morph into different types of cells. When it comes to issues covered in major news stories, the public's understanding of scientific issues increases. Fully 91 percent know that aspirin can help prevent heart attacks, 82 percent know that global positioning system (GPS) technology is dependent on satellites for information, and ...