Oy.

There’s a new paper out by Marissa Harrison (of Penn State) et. al. collected historical data on the crimes of 112 murderers who killed 3 or more people with at least one week between each murder (killing more quickly did not disqualify one so long as there were at least 3 periods of single/multiple murder that were separated from all other periods of single/multiple murder by a full week on each side). 55 of the killers were women. This is the all but 9 of the women serial killers in the US from 1821 to 2008 – at least that they could find. From the men serial killers during that period they selected “matches” of the women subjects. “Matches” here means that they were approximately equivalent to their women counterparts on certain variable which the researchers wanted to control.

Then they ran some criminological statistics on the gender-separated populations & looked for differences. The resulting research was published in the Journal of Forensic Psychiatry & Psychology. NewAtlas, reporting on the study, tells us that:

The majority of female serial killers came from middle or upper class backgrounds and were college-educated, while the majority of male serial killers were less educated and from lower class backgrounds. The method of killing also dramatically differed between the sexes, with nearly half of the women using poisoning to murder their victims, while men preferred asphyxiation or shooting.

… A stunning 90 percent of female serial killer victims were someone familiar to the killer, whereas men were much more likely to target strangers. In fact, 85 percent of male serial killer victims were strangers compared to less than 15 percent of female serial killer victims.

Ah, but this isn’t dramatic enough, of course, to gain the media attention that the study seems to be attracting. No, the study is attracting attention because Harrison is an evolutionary psychologist and she has herself a theory which is a theory which is hers. And it is that women serial killers are “gatherers” and men serial killers are “hunters”:

Furthering the hunter-gatherer thesis distinction, 65 percent of male serial killers were found to stalk their victims before murder, while only 3 percent of female killers did the same.

Now, I don’t have access to the whole paper right now, but holy maroney, Batman, the truth of this observation seems to be heavily dependent on the study’s operational definition of “stalking”. It seems to me that if the person is familiar with the killer, “stalking” can be done in the course of one’s normal routine. Some of these killers, for instance, are likely to be nurses as the briefest of searches for women serial killers quickly turns up multiple instances of killer caregivers. For example, this list of 10 “most famous” women serial killers includes 2 US nurses who killed patients (and one nurse from Europe). Others like Dorothea Puente were non-nurse caregivers (she ran a boarding house for elderly persons & those with disabilities, killing many of her boarders). Still others like Nanny Doss & Waneta Hoyt killed their own children. Doss also killed 4 husbands and 2 of her sisters.

Harrison et. al. contend that only two women killers “stalked” their victims, which would seem to mean that the authors must have concluded some of these women were not hunter-killers, but rather gatherer-killers who did not stalk anyone (though I can’t say for sure until I know whether or not these examples were or were not included in the study sample). Yet given the circumstances of the murders attributed to them, is it fair to say that killers like these 5 women did not “stalk” their victims? Tracking their victims’ whereabouts and habits to determine vulnerable moments before striking would be easily accomplished as part of daily home or work life. But does this make it not stalking? Wouldn’t it be just as reasonable an interpretation to say that women serial killers were much more invested in the hunt, to the point that they only killed after months or years of stalking?

And what is the difference between stalking and hunting in this context anyway? The authors have some thoughts on that:

the researchers note that female serial killers were three times more likely to be motivated by financial gain compared to male killers. It is suggested in the study that this is, “in line with the “gatherer” hypothesis, female serial killers seem to be gathering resources as a result of their killings.”

But that makes no sense. What is the point of hunting, after all, except to gain resources? “Resource gain” is then not expected to be correlated more with hunting-style killings or with gathering-style killings, even if the authors could be trusted to have correctly identified which killings fall into which category. You can’t say that this is “in line with the ‘gatherer’ hypothesis” if it is to be equally expected under each of two mutually exclusive hypotheses, only one of which is a “gatherer” hypothesis.

On the other hand, male serial killers are 10 times more likely to have a sexual motivation underpinning their crimes. The researchers hypothesize this to be a kind of “aberrant form of mate-seeking.”

And… so this is hunting behavior? We don’t actually hunt our mates. I’m also not aware of any research showing that chimps or bonobos or gorillas engage in literal “hunting” for mates in the sense of stalking them and then grabbing them, even if we exclude killing potential mates as “aberrant” and maladaptive.

So, the research shows that women spend more time familiarizing themselves with the locations, movements, habits & patterns of their victims, yet Harrison et. al. categorize them as “gatherers” who don’t stalk. Men who kill serially, on the other hand, are “hunters” who don’t prolong the hunting aspect and instead are frequently motivated by sexuality or sexual associations, even though mating is not shown to be accomplished via “hunting” of any duration in humans or their closest evolutionary relatives.

Seriously, what kind of weird shit is this?

And of course, there is no neurological structure, much less any developmental pathway that creates such a structure, much less any specific gene or pattern of gene expression regulating that developmental pathway that can currently account for preferentially murdering as a “gatherer” or as a “hunter” (under the operational definitions of “gatherer killer” and “hunter killer” used in this paper). And even if we had those, we would still have to show that those structures, pathways, and genes function differently in female-bodied persons from the way that they do in male-bodied persons. And even if we had that, we’d still have to confirm that just becoming a serial killer isn’t so far outside the norm that the average patterns for such structures, pathways & genes among female-bodied serial killers don’t differ so greatly from the averages for all female-bodied persons that research on the data set becomes useless for drawing conclusions about female-bodied serial killers.

In short, once again a small group of evolutionary psychologists have taken data about historical hunter-gatherer societies, assumed that those data accurately reflect pre-historical societies of homo sapiens and even of all social groups of pre-homo sapiens hominins more closely related to homo sapiens than to bonobos. Then they assume that since these characteristics must have been present and stable over evolutionary time, they must have been acted on by natural selection over that time. Then they assume that since some gender differences in behaviors can be observed in that data, natural selection must have acted on the different human sexes separately for all those currently gender-different behavioral patterns. This, of course, requires them to assume that the behavioral differences are all or largely determined by heritable genetic and/or epigenetic factors. But it also requires that traits that make one a better hunter make one a worse gatherer, and vice versa, or there would be no selective pressure to eliminate in one sex a trait that was beneficial to another. Finally, it assumes that it was evolutionarily possible to limit the expression of that trait in only a single sex.

…and in doing all this, they still can’t even recognize basic truths about the data upon which they are relying or they wouldn’t distinguish the “gatherer hypothesis” of serial killing from the “hunter hypothesis” of serial killing on the basis of whether or not one ends up with resources after the murders in question.

I actually really want to gain access to this article (and will probably arrange it soon – maybe I’ll just head back to the university & browse it in the library, or maybe it will be available through my public library) but not because it looks particularly promising or informative. This looks like just incredibly bad science, though I can’t be sure until I read the whole thing. If I have time, I’ll acquire it & write more on it for you later. In the meantime, though, remember never to hunt if you want to end up with resources! Also, don’t depend on any males in your life for providing resources. Cis men are really, really bad at acquiring resources. That’s just evolution!

On the other hand, they’re highly prone to confusing the impetus to mate with the impetus to kill. We can be relatively sure this is because they used to fuck the same antelope they hunted in Africa or something and the whole mate/kill thing got evolutionarily confused. So don’t blame the poor dears. But on the other hand, make sure all your sex partners are trans folk, intersex folk, or cis women. Really, evolutionary psychology tells us this is the only wise choice.

PS. Avoiding Marissa Harrison might not be a bad idea either.