The social environment shapes the individual behavioural profile during early phases of life. In guinea pigs the behavioural profile of daughters whose mothers experienced social instability during pregnancy and lactation (UE-daughters) are behaviourally masculinised. Since guinea pigs are domesticated the question arises whether this phenomenon was brought about by domestication or whether it represents an adaptive behavioural mechanism inherited from their wild ancestor, the wild cavy. This study, therefore, investigates the effects of an early unstable social environment on the biobehavioural profile of daughters in wild cavies and compares these effects with the findings in the domestic form. Our results show higher frequencies of aggression and play behaviour in UE-daughters, indicating a comparable behavioural masculinisation as in guinea pigs. Thus, the observed behavioural changes in UE-daughters cannot have been brought about by artificial selection during domestication. Rather they represent maternal effects evolved through natural selection.