Washington Post has a summary of a new study on American female serial killers. Its headline is "The surprising but curiously logical differences between male and female serial killers."
Astonishingly, those differences don't seem to include the vast difference in the numbers of male and female serial killers, at least the ones who are caught. Well, the summary doesn't mention that.
The study uses evolutionary psychology to explain why female serial killers have apparently different motives for killing and different modi operandorum (m.o.s).
Thus:
Although female serial killers, like unhappy families, are each horrifying in their own way, Harrison found some striking similarities among her subjects. Most of them came from fairly mundane backgrounds, their primary weapon was poison, and nearly all of them killed people they knew, often their own family members. By comparison, most victims of male serial killers are unknown to their murderer.
“Female serial killers gather and male serial killers hunt,” Harrison said. “That was very interesting to me, as an evolutionary psychologist, that it reflects kind of ancestral tendencies.”
Harrison also saw evidence of evolutionary influences in what drove women to kill. While most murders by male serial killers tend to involve sex in some way — a 1995 study found that male serial killings are characterized by a desire for domination, control, humiliation and sadistic sexual violence — women are more likely to kill for money or power.Bolds are mine.
“It struck me that women would kill for resources, which was their primary drive in the ancestral environment, and men kill for sex,” she said.
That's really neat! At first glance it's simple and somehow fitting. But then I started thinking more about all that gathering vs. hunting and resources vs. sex business, and I realized that it's far too simple, even simplistic.
The reasons are pretty obvious, in my view. Take that gathering vs. hunting distinction:
First, we don't actually have information on the exact division of labor in some presumed ancestral era of evolutionary adaptation. Did the men go out every single day to hunt, without fail? Did the women never go? When the berries were all ripening at the same time, did the men just hang out somewhere telling stories or where they out hunting? What if hunting was sporadic? Who hunted small animals and fished? What if men gathered, too? One study of more recent gatherer-hunter societies found that most of the calories the tribe consumed came from gathering, and that suggests to me that men gathered, too.
Second, it's hard to see why one form of serial killing is like gathering and one form like hunting. Gatherers probably had to walk long distances (and, indeed, the usual assumption is that the evolutionary adaptations happened in small nomadic family groups so everybody moved). That the female serial killers were more likely to know their victims doesn't make their form of killing like gathering, or at least I cannot see why that would be the case.
The only way I can imagine such a semblance is by thinking of the victims of the female serial killers as staying put in one place, so that the killer "harvests" them. But the victims of male serial killers might also stay in one place where he goes to kill them?
I'm confused on that, especially given that I haven't read the original article (forty dollars).
Third, the differences between male and female serial killers in the US from 1821 to 2008 cover a lot of years when certain types of women, "respectable ones," just didn't go out alone that much and probably not at all late at night. Couldn't it be equally likely that female serial killers selected their victims on the basis of access to victims or opportunity, as defined by the gender norms of the society?
What about the motives of resources vs. sex? To remind you, this is the relevant quote:
Harrison also saw evidence of evolutionary influences in what drove women to kill. While most murders by male serial killers tend to involve sex in some way — a 1995 study found that male serial killings are characterized by a desire for domination, control, humiliation and sadistic sexual violence — women are more likely to kill for money or power.Bolds are mine.
“It struck me that women would kill for resources, which was their primary drive in the ancestral environment, and men kill for sex,” she said.
How do domination and control (assumed male traits) differ from power (assumed female trait)?
What Harrison probably refers to in those primary drives is the Evolutionary Psychology (EP*) argument that women look for resources in their male mating partners while men look for youth and health (fertility) in their female mating partners. I've written about the problems with that simplified theory before. If evolutionary adaptations indeed happened when our prehistoric ancestors lived in small family-based nomadic tribes, the form resources would take is quite different from a fat bank account or even from a barn full of grain.
Indeed, the resources a person "owned" were probably embodied. Women would have looked for young, healthy, strong and skilled men to father their children. When you define resources from that angle the choices of men and women begin to look more similar.
Even if we ignored that and the long history of women not having equal access to resources through inheritance and the labor market (which would increase the relative number of women who would take to crime to get them), there's a logical problem with the basic argument. In the EP story it is men who are assumed to want to acquire resources so that women will then choose them to have sex with. In other words, men, too, would want to have resources.
So why don't male serial killers have that goal, you might mutter?
But they do! If we define a serial killer the way the WaPo summary suggests (anyone who kills three or more people with a “cooling-off period” of a week or more between each murder), the Chicago gangsters of the 1930s would qualify and so would today's Mexican drug lords. In fact, many types of criminals kill serially for resources.
Perhaps the study defined a serial killer differently. But if it did, it may have overestimated the types of murders based on desire for domination and sadistic sexual violence in the overall count of serial killings carried out by men.
Then there's the intricate question about the meaning of this evolutionary explanation: Do the researchers argue that men kill for sex because that is an evolutionary adaptation? It cannot be the case, because killing the woman you have just raped makes passing any genes to the next generation impossible.
Or is the idea that these patterns are distortions of evolutionary adaptations? If so, why have they survived?
I am asking that question seriously, given that some Evolutionary Psychologists seem to look for an evolutionary advantage in suicides, say.
Granted, Harrison left the exact meaning of all that open in the interview WaPo quoted. But she does argue (without proof as there can be no proof) that looking for resources was the primary drive for women** in the unspecified ancestral environment, and contrasts that with men's drive for sex.
It's not that those theories aren't interesting. But there are alternative theories*** not based on simple evolutionary hypotheses and there are probably even more complicated (and realistic) evolutionary psychology hypotheses.
The topic of the study, horrendous as it is, is also thought-provoking. Why are men so much more likely to be sexual serial killers than women? Why are there many times more male serial killers than female serial killers? Are there ethnic or racial differences in the total numbers of serial killers, in the percentages of male serial killers and of female serial killers? And to what extent is it meaningful to apply evolutionary hypotheses to those types of serial killers who clearly should be discussed under the title abnormal psychology, psychopathy and so on?
Sigh. My apologies for not spending money on the article itself. Should anyone desire to donate the price to me I promise to read it and amend anything in this post that needs amending.
----
*I use capital letters for the weird kind of evolutionary psychology which I most often criticize on this blog. I should stress that I'm not criticizing Dr. Harrison's arguments themselves but the manner in which they are reported in the WaPo summary.
** In one sense the primary drive of everyone is for resources (necessary for survival), if we define those to include getting food and water as often as needed. But I think Harrison means something different here.
***The impact of social norms on the opportunities for murder, the impact of body strength differences on the choice of the instruments of murder and on the types of victims selected. The victims should be weaker than the killer which limits female serial killers more than male serial killers.