Table 1. Science knowledge questions used in studies 1 and 2.

Total correct responses were summed; 7b was displayed only if 7a was answered correctly.

Study 1: GSS

1. It is the father’s gene that decides whether the baby is a boy or a girl. 2. Electrons are smaller than atoms. 3. The center of the earth is very hot. 4. Lasers work by focusing sound waves. 5. All radioactivity is man-made 6. Antibiotics kill viruses as well as bacteria 7a. Does the Earth go around the Sun, or does the Sun go around the Earth? 7b. How long does it take for the earth to go around the sun?

Study 2: LSAY

1. Antibiotics kill viruses as well as bacteria. 2. Nuclear plants destroy the ozone layer. 3. More than half of human genes are identical to those of mice. 4. Ordinary tomatoes, the ones we normally eat, do not have genes whereas genetically modified tomatoes do. 5. For the first time in recorded history, some species of plants and animals are dying out and becoming extinct. 6. Which travels faster: light or sound? 7a. Does the earth revolve around the sun, or does the sun revolve around the earth? 7b. How long does it take the earth to revolve around the sun?