Social instability has negative effects on various social behaviors and social traits, but some are still understudied and the way they are affected is still not well understood. This is the case for courting behavior and social bonding, which are understudied when the exposure is during adulthood. Here, I studied the effects of social instability (SI) on aggressive behaviors and female courting receptivity. To do this, 12 female adult guinea pigs were separated into four groups: two were socially stable and two were exposed to social instability. Social instability was induced by changing group composition every three days for a month. Once the treatment finished, I created 4 groups with different behavioral phenotypic compositions. Then, I introduced a male during the first two days (acute effects) and days 8-9 (medium-term effects). The results suggest that SI significantly increases aggression rates, but not courting rates; meanwhile, group composition significantly affects courting rates, but not aggressive rates. Individuals exposed to SI had overall less successful courting rates and higher aggression rates, the latter being related to a lower capacity to form and maintain social bonds. In conclusion, exposure to SI led to an increase in aggression rates and possibly to a lower capacity to form social bonds, but doesn’t directly lower female receptivity, although changes in group composition do. These results show how social instability may affect social bond formation through increased aggressive behaviors and how exposure to social instability affects courting receptiveness through changes in group behavioral dynamics.
