A farmer is being troubled by coyotes eating his sheep. In an attempt to solve the problem, he kills a sheep and laces its body with a nausea-inducing drug. He leaves the sheep out where he knows the coyotes roam

The lissencephalic individual in the chapter's opening vignette had a brain that lacked:

a. Gyri b. Sulci c. Convolutions d. All of the above

Causation cannot be inferred from correlational studies because

a. they are so low in external validity. b. they do not involve the manipulation of variables. c. they are always conducted outside of the research lab. d. researchers have too much control over the variables in correlational research.