Table 1.

A list of the observed behaviors divided into four categories: affiliative, aggressive, dominant and submissive behaviors

Affilative Behaviors
Co-threatening/solicit co-threatening	alternating threats and glancing at the partner, who may or may not join in the threatening.
Grooming	manipulation, brushing, or licking of fur (or eyes, wounds) of another animal with the mouth and/or both hands.
Lip-smacking	bringing the lips together rapidly, resulting in a smacking sound; teeth are covered.
Mounting through the panel	common usage, with or without pelvic thrusting and penetration and with or without foot clasp.
Playing	Non-aggressive, lively actions performed with another individual with or without direct physical contact. Play should not be accompanied by pilo-erection. Play can be accompanied by a play face and/or laughing or other vocalizations.
Aggressive Behaviors
Aggressive contact	physical contact that may or may not result in injury ( (e.g. mouth fight, pushing, pulling, grabbing, minor scratching).
Lunging	high-speed aggressive intentional movement toward another animal.
Threatening partner	at least one of the following: 1) stare (visual fixation in an aggressive context. Body appears rigid. Often accompanied by pilo-erection. May also include ears flattened against the head, brow retracted, round mouth, teeth partially exposed [open-mouth stare]). May also include head bobbing 2) threat gesture: slap surface while oriented toward partner or slap at the partner without making contact.
Dominant Behaviors
Displaying	vigorous shaking, slamming, or bouncing off of the cage.
Supplanting	animal approaches within proximity of another individual, resulting in the latter's movement away from the current space.
Submissive Behaviors
Avoiding	immediate movement away from an approaching animal once the approach begins.
Cowering	cringe in a crouched position with limbs held beneath the body and head lowered.
Eye Averting	avoidance of eye contact with animal with whom one is directly engaged in a social interaction (may include an approach, threat, grooming bout). Body of the actor is typically oriented toward the social partner while the gaze is oriented away.
Fearful grimacing	grin-like facial expression involving retraction of the lips, exposing teeth. May be accompanied by vocalizations, such as: shrill, high-pitched calls, including screeching, squealing, and squeaking.
Rump presenting	a posture involving a stance on all fours with the hind quarters elevated and the tail raised. In some animals the tail may be lifted to the side rather than raised. In some instances, animals may place their heads between their legs.