Sex differences in serial killers

Research directly comparing empirical data of the behaviors and crimes of male serial killers (MSKs) versus female serial killers (FSKs) within one study is nonexistent. This study sought to make such a direct comparison. We examined sex differences in serial murder that may be byproducts of ancestral tendencies. Specifically, we proposed and tested a "hunter-gatherer" model of serial murder. Using the mass media method to collect archival data, we obtained information about 55 MSKs and 55 FSKs (matched for age of first murder) who committed their crimes in the United States from 1856 to 2009. We found that MSKs more frequently act as "hunters," stalking and killing targeted strangers in dispersed areas, while FSKs more frequently are "gatherers," killing those who are around them and familiar to them and gaining profit from their crimes. We also documented other sex differences between serial murderers. We discuss these findings from an evolutionary psychological perspective.