Table 1. Sequential Partner Preference.

Behavioral Ethogram.

Subject's behavior	Description	Measure per trial
Contact	Subject touches test cage (with any part of the body except tail)	Frequency
Latency to contact	Latency to first contact with the test cage or stimulus animal during each trial	Duration*
Location	Subject's location in the home cage	Frequency
Subject initiated behavior	Description	Measure per trial
Lipsmack	Lip movement with smacking sound	Presence/Absence
Chest rub	Rubbing chest area with hand or cage	Presence/Absence
Tail-lash/Arch back	Animal arches back, wags tail	Presence/Absence
Vocalization	Animal engages in calling behavior	Presence/Absence

^*Time in seconds, approximation was obtained by multiplying interval number by 15