Table 2.

Operational definitions of general (nonsocial), social behaviors, and vocalizations^a

Behavior	Description
General (nonsocial)
Locomotion	Walks, runs, climbs or jumps
Manipulation	Handles, chews, licks, moves, or smells objects or cage parts
Passive while alone	Inactive, stays in one location
Self-directed	Engages in self-directed behaviors, i.e., self-grooms, hugs head, self-grabs and bites, presses face with hands, self-holds, closes fists, self-clutches, sexually self-stimulates, prone, or head on chest
Motor stereotypies	Repeatedly paces, somersaults, circles, swings
Social
Approach	Initiates social contact; moves body or head toward the conspecific
Mounting	Mounts the conspecific
Aggression	Makes threatening gestures (i.e., mouth threat, head or body lunge, cage shake) toward or hits, grabs, or bites the conspecific
Isolation	Sits alone
Contact	Touches or holds the conspecific
Play	In contact with the conspecific, includes chasing, wrestling, and “rough and tumble” behaviors
Groom conspecific	Subject grooms the conspecific
Solicitation of grooming	Subject presents for grooming
Receives grooming	Subject is groomed by the conspecific
Withdrawal	Moves away from the conspecific when approached
Total social contact	Includes contact, dominance, grooming, and play
Vocalizations
Affiliative vocalizations	Coo, grunt, girney
Defensive vocalizations	Bark, scream

^aThe behavioral category and description for each of the general (nonsocial), social behaviors, and vocalization behaviors analyzed in the manuscript.