Genetic selection for avoidance behavior in the rat.

Long-Evans rats were selectively bred for over 20 generations using two behavioral criteria: (1) limited responding to the warning signal during ten pretest trials and (2) either good or poor avoidance behavior during 60 avoidance training trials in a two-way shuttlebox. The results suggest that avoidance behavior in the rat is a heritable characteristic that may be selected independently of activity level.