Psychopathy has been historically associated with a lack of emotion. However, some authors argue that psychopathy may represent a tendency to externalize the experience of unpleasant emotions, including shame, what could be seen as an adaptive strategy within an evolutionary framework. Nevertheless, empirical research investigating this hypothesis is scarce. Using community (n = 295) and forensic (n = 300) male youth samples and a set of self-report measures, this study tested an evolutionary model involving pathways linking the impact of harsh rearing experiences (traumatic shameful experiences and warmth and safeness experiences) to psychopathic traits, as well as the indirect effects of external shame and shame coping strategies in that association. In addition, this study tested the invariance of this model across samples. Results indicated that the impact of harsh rearing experiences was directly and indirectly (through external shame and shame coping strategies) linked with psychopathic traits. The model explained psychopathic traits in forensic and community samples, though differences in some of the pathways were found across groups. Findings offer support for conceptualizing psychopathic traits as an adaptive strategy to cope with the impact of harsh rearing experiences, opening new pathways to prevention and intervention efforts.