Fig 3. Mean ± SEM time (seconds, s) spent engaging in prosocial behavior and aggressive behavior in a social interaction test with a novel opposite-sex conspecific (beige), novel same-sex conspecific (green), and familiar same-sex sibling (blue).

Male and female voles were (A) more prosocial and (B) less aggressive with their siblings compared to other stimulus types. (C) Prosocial behavior and (D) aggression varied by the type of conspecific voles interacted with for all age groups except the eldest group, PND300-320. (C) Aggression differentially varied by the type of conspecific males and females interacted with; females were more aggressive in interactions with opposite-sex conspecifics compared to males. Dots represent individual data points. * indicate statistical significance.