ABSTRACT
This chapter looks at psychopaths, the quintessential criminals, and the quintessential cads. Such individuals really highlight the tight fit between high mating effort and criminality. The Psychopathy Checklist-Revised is the gold standard for defining a psychopathic personality. Psychopathy is widely considered an alternate evolutionary adaptation, for there is no evidence that it is the result of early social or environmental factors. It is a fast life history strategy that is apparently biologically rather environmentally induced. Many lines of neurological and physiological evidence support this, including ventromedial pre-frontal cortex and amygdala impairments, and metabolite ratios of the dopaminergic and serotonergic systems. All of this evidence points to a reward-dominant brain. The oxytocin and testosterone ratios found in psychopathy also point to a callous personality lacking in empathy. Sociopathy is also explored. Although overt aggression, impulsivity, and criminality are hallmarks of sociopathy, they are less closely related to psychopathy, and sociopathy is less tied to genetics than psychopathy. Thus, the developmental environment can produce sociopaths but not psychopaths.
