Table 1.

Operational definitions of observed behaviors.

Behavior	Description
Defense-associated vocalizations	Calls consisting of barks and screams[this excludes affiliative vocalizations, such as coos]
Cower	Withdrawal to the periphery of the cage in a crouched or recoiled position with an upward directed gaze
Escape	Sudden movement/startle response, typically consisting of moving explosively from one side of the cage to the other
Attack of inanimate objects	Bitting, hitting, or throwing objects such as toys and/or ratting cage bars
Motor/postural asymmetry	Quadrupedal circling, head deviation greater then a45 degree from the midline

Behaviors that were coded from video-records.