Familiarity enhances moment-to-moment behavioral coordination in zebra finch (Taeniopygia guttata) dyads.

An individual's ability to respond to and align with the behavior of others is a fundamental component of social behavior. Zebra finches form lifelong monogamous pair bonds; however, zebra finches are also gregarious and can form strong social bonds with same-sex conspecifics. Here, we quantified behavior during brief 10-min reunions for males and females in five types of social conditions: monogamously bonded opposite-sex partners, familiar same-sex, familiar opposite-sex, novel same-sex, and novel opposite-sex dyads. We analyzed these interactions in three ways. First, we quantified overall activity levels (call and movement rates) for each individual. Second, we measured how coordinated calls and movements were by calculating (a) the percent difference in activity rates as an estimate of how similar calling and movement activity were between individuals within a dyad, and (b) the sliding correlation coefficients for time-stamped calls and movements for each dyad. Finally, we described multimodal behavioral profiles of coordination using principal component analyses. Overall, females were more active than males. For both females and males, activity levels as well as the coordination of calls and movements were significantly affected by social condition. In general, monogamous partners, female familiar same-sex dyads and familiar opposite-sex dyads were the most coordinated. This effect of familiarity shows that moment-to-moment behavioral coordination can be influenced by prior social experiences. Quantifying patterns of coordination or social synchrony may prove valuable for understanding the effects of social experience on brain and behavior. (PsycInfo Database Record (c) 2020 APA, all rights reserved).