What Do 3 Million Myopes Have to See About That?
I recently happened upon an old VICE article about a lovely feminist who tried to introduce International Castration Day. Her utopian vision involved castrating 90% of the world's male population as that, in her opinion, would solve most of the world's problems, including males' rapy tendencies — since the remaining 10% would each get to enjoy their own small harem.
Even though the whole thing strikes me as a hoax, her thoughts are well laid out and argued, and I bet many a male would very much like to live in her ideal version of the world, though in their place I wouldn't bet on it to happen.
Putting a utopia inside a crystal ball is improbability squared.
Source: maxpixel w/ CC0 Public Domain license.
I decided to write this short post (though note that my 'short' is other people's 'long') to look at whether males might indeed be more rapy than women, and other related stuff, but mostly just expanding a bit on my last two posts where I talked about hormones and what they do to us and how they separate the sexes. The VICE article is really just a springboard-excuse for me to talk some more about stuff that I find interesting!
Are We a Polygynous Species?
The bigger the polygynouser.
Source: Jim Richmond w/ CC BY-SA 2.0 license.
I won't treat this exhaustively. But I will note that there's probably a good biological reason why many males would enjoy the Femitheist's utopia as laid out in the VICE article — as long as they ended up in the 10%, that is!
Just looking at an average male and female human, there is something that immediately screams "polygynous" to a biologist — and he doesn't even need to wear his glasses if he needs them, a fuzzy picture will do just fine — and that is our size discrepancy:
Large male size relative to female size (sexual size dimorphism) is observed in animals with a high degree of male sexual competition, that is, polygynous species
You see, males need their large size to fight other males, the prize being females. That our size difference is small compared to some other species means that "ours is a moderately polygynous species".
Blood Spiked with Androgens: Do Androgens Cause Rape?
Source: pastel100 w/ Pixabay License.
In a report that did a combined analysis of studies of humans, nonhuman primates, and nonprimate mammals, the results — although they were couched in fancier names in the report — were basically separated into very strong, strong, and suggestive. Under very strong they listed "Assertive erotic sexual behavior".
In case you take "assertive" to mean something less sinister than what it really means, let me pull your fears out of bed by noting that it includes rape. Specifically:
persistent attempts to mount and/or copulate, even when the recipient animal is noncooperative and possibly even actively resisting the attempts.
No wonder they grouped that together with "forcible rape or attempted forcible rape" in humans.
Note that those who lean more toward sociological rather than biological explanations of behavior, will often claim that sex differences between males and females are the result of learned behavior. But what if actually lack of rape is the result of learned behavior? In our current cultural climate we are very actively trying to dissuade people (mostly men) from raping. What if, in our natural condition, rape was much more prevalent and much more comparable to what we see in all other mammals?
And I do mean all:
on average, there is no mammalian population in which males fail to be more forceful and/or persistent in their erotic sexual behaviour than females..
This of course is concordant with a number of posts I've written lately investigating whether men are more sexual than women. (Spoiler: They are.)
Note that sexual behavior can be enhanced by chemically administering androgens to a subject (regardless of the subject's sex), and that lowering androgens (either by drugs or by castration) lowers assertive sexual behavior. Yes, International Castration Day has some science to back it!
Are Men More Tenacious SBD?
Source: Sven Mandel w/ CC BY-SA 4.0 license.
Other areas in which there is "beyond reasonable doubt" evidence (i.e. strong evidence) are status-related aggressive behavior (i.e. aggression between males for rank and dominance).
Under "very well established" the paper lists the ability to rotate an object in one's head and to navigate space.
Also, to procure, mark, patrol, and defend said space.
Also, pain tolerance.
Also, an interesting thing called "retarded acquisition of aversive conditioning (RAAC)", or what I prefer to call "Skinner-be-damned (SBD)". Basically, a person with RAAC/SBD is a person who keeps performing an action despite significant punishment being contingent upon doing it.
So yeah, men are more "retarded" that way ("stubborn" is another possible adjective). But it also explains their single-minded pursuit of subjects, which might explain why they may excel at them and why there's so many more men in the genius category compared to women (see a previous article of mine).
A related sex difference (but one categorized under "strong evidence outside the human species") is "task control-oriented tenacity", which is:
The tendency for animals to stick to a task long after all ‘external’ reinforcement has been terminated.
Again, stubbornness is an apt synonym. Note that although the evidence for humans is not strong, it's still corroborative of the studies from other mammals: "human males have been found to display greater tendencies to persist at long tasks to completion than females".
In case you're wondering whether we're still on the topic of hormones, I'll remind you that all these categories involve studies that manipulate androgens, and increasing them increases the behavior in question, while decreasing them decreases it.
An example of androgen manipulation in humans is a study of 22 female-to-male transsexuals that were tested twice, once shortly before and then 3 months after their androgen treatment. Their spatial performance abilities improved while their verbal fluency diminished. This jibes with the spatial and verbal cognitive differences between men and women as revealed in the rest of the literature, but here the cause is more directly teased (as there are other differences between men and women besides hormones that could explain the differences), though strictly speaking it's still correlation rather than causation at this point.
Note that the researchers, in order to make sure the performance of the subjects was not influenced by possible stereotypical beliefs the subjects might have held about cognitive differences between the sexes, also tested them in a topic in which the literature finds no sex difference, but which the subjects might believe there is: verbal reasoning. The results?
As expected, the treatment did not influence verbal reasoning performance..
Maps, Spatial Abilities, & the File Drawer Problem
The file drawer problem.
Source: OpenClipart-Vectors w/ Pixabay License, modified.
Spatial ability and map-ability are quire related, and one of the reasons @lordnero loves maps might be because he's a male:
Map-learning and spatial ability appear to be related in the present study, and a male advantage is found for both abilities.
"In the present study"? Give me a break. I need more than one to believe that...
The male advantage in spatial ability is well-documented, as is the female advantage in verbal ability
"More than one" was rhetorical. I meant I need quite a few to be convinced that....
The overall analysis of 286 studies revealed a mean weighted d of 0,37 (z = 2.61, p < .01), which demonstrates that sex differences in spatial abilities favoring males are highly significant.
286 is indeed quite a few. But then again, who knows how many null finding papers go unpublished...
The fail-safe analysis indicated that 178,205 studies with nonsignificant results would be needed to offset the significance of the results at the .05 level.
Oh boy. Believing that 178,205 studies have been shelved is quite a stretch.
The impossible file drawer problem.
Source: OpenClipart-Vectors w/ Pixabay License.
This deserves a longer quote:
The results of the present analysis strongly suggest that sex differences in spatial abilities do exist. The astronomical overall fail-safe number of 178,205 is much larger than the criterion suggested by Rosenthal (1980), that is, 5(286) + 10 = 1,440. This finding makes it obvious that the file drawer problem is not plausible as an alternate explanation. It is unlikely that over 170,000 studies on sex differences in spatial abilities with nonsignificant results are gathering dust in file drawers around the world.
But what's the evolutionary reason men are better at navigating (map + spatial ability)? The most common suggestion is that males had larges range sizes than females, due to the males being the hunters and the females being the gatherers, as well as the rearers:
Early hominid males may have had naturally larger ranges than females due to the division of labor, as the men would hunt for food in the traditional hunter-gatherer society [...] Females may have stayed closer to the home base, in order to care for infants, effectively making their ranges smaller.
Sounds reasonable enough, but what's the evidence for it? Science is not just about coming up with theories, but mostly about coming up with ways to test those theories, to see whether they're right or wrong. Unless some prediction can be deduced from the assumption laid out in the quote above, it's just a just-so story. Or it was, until this happened...
What Do 3 Million Myopes Have to See About That?
Source: Bonhams w/Public Domain license.
Two researchers decided to deduce a prediction from a model much similar to the one quoted above. "We sought to deduce a hypothesis that could be falsified", they wrote. They reasoned that, "Selection pressures for clear vision across moderate distances on a nonwooded, open savannah would pertain more to males than to females." This led them to formulate the following prediction:
Based on these assumptions we predicted that deficits in distance vision (defined as myopia) would be more prevalent in contemporaneous women than in men. That is, over generations, men with myopia would tend to have been filtered out of Homo’s gene pool. Women with myopia who fulfilled traditional feminine roles would be less subject to such filtration.
So they undertook to find sources where this could be ascertained. It proved to be more difficult than they expected, since most literature didn't seem to think it important to indicate the sex of the eye patient. But finally they located several sources that included the sex of the sampled subject, and they came from several countries. These studies tested for several vision problems, and among them were almost 3 million people with myopia. The results?
The data supported the hypothesis: For the 2,982,000 cases of refractive myopia in the DA sample, 58.0% were females and 42.0% were males
The DA was a specific US sample. Other samples, from countries like Israel, Japan, and Finland, gave similar results, often more extreme (almost twice as many female myopes compared to men), and sometimes less (the smallest being ~ 11%).
Alternative explanations of the data were quickly disposed of. For instance the idea that women outlive men, and vision issues arise at older ages, therefore the women will be overrepresented, was destroyed by the mere fact that the median age of the subjects was 24 yo. Furthermore, many of the studies were conducted on prepubescent children, and showed the same results.
Another alternative explanation—that the culture may be more solicitous toward women compared to men—was deflated by noting, again, that the school data was collected based on the condition that a person was a student, not a sufferer of eye problems; and secondly, the authors assessed visits to eye doctors due to eye injuries, and found that only about 20% of them were women. This of course could be because men are more likely to get injured because of their more dangerous lifestyle, but it does shift the onus of proving that the culture is more solicitous toward women to the other side.
Indeed, a priori, the expectation would be that males would suffer more from myopia, seeing as "the males’ greater vulnerability to a host of maladies might well lead a theorist to expect a greater male incidence of myopia." (For an explanation of why males are prone to more adverse mutations, see a previous article of mine).)
Two ways to being partial.
Source: Guido Gerding w/ CC BY-SA 3.0 license.
A strong undercurrent of this post has turned out to be about science method and bias rather than hormones. I would like to end it by reminding the reader that bias can go both ways, one of which we often don't expect. Plenty of scientists today are complaining about PC culture, are actually worried of getting fired for reporting what the science says (listen to this sex differences researcher for instance). This might lead to null findings actually getting published, while positive findings go unreported:
results found in the literature may not accurately reflect findings obtained in psychological research because of selectivity among scientists as to which findings to report. For example, findings that males are more assertive than females, if deemed "politically incorrect," may more often go unreported than findings of no gender differences in assertiveness, thus resulting in an artifactually deflated effect size in the results from a metaanalysis of studies in the literature.
Reporting the truth, apparently, can be politically incorrect.
But not reporting it is scientifically incorrect! And we all know science > politics.
Weisfeld, G. (1997). Puberty Rites as Clues to the Nature of Human Adolescence. Cross-Cultural Research, [online] 31(1), pp.27-54. Available at: https://doi.org/10.1177/106939719703100103.
Ellis, L. (1986). Evidence of neuroandrogenic etiology of sex roles from a combined analysis of human, nonhuman primate and nonprimate mammalian studies. Personality and Individual Differences, [online] 7(4), pp.519-552. Available at: http://psycnet.apa.org/doi/10.1016/0191-8869(86)90131-5.
Van Goozen, S., Cohen-Kettenis, P., Gooren, L., Frijda, N. and Van de Poll, N. (1994). Activating effects of androgens on cognitive performance: Causal evidence in a group of female-to-male transsexuals. Neuropsychologia, [online] 32(10), pp.1153-1157. Available at: https://doi.org/10.1016/0028-3932(94)90099-X.
Galea, L. and Kimura, D. (1993). Sex differences in route-learning. Personality and Individual Differences, [online] 14(1), pp.53-65. Available at: https://doi.org/10.1016/0191-8869(93)90174-2.
Sanders, B. and Soares, M. (1986). Sexual maturation and spatial ability in college students. Developmental Psychology, [online] 22(2), pp.199-203. Available at: http://dx.doi.org/10.1037/0012-16188.8.131.52.
Voyer, D., Voyer, S. and Bryden, M. (1995). Magnitude of Sex Differences in Spatial Abilities: A Meta-Analysis and Consideration of Critical Variables. Psychological Bulletin, [online] 117(2), pp.250-270. Available at: http://dx.doi.org/10.1037/0033-2909.117.2.250.
Mackey, W. and Johnson, J. (1994). Gender Dimorphism of a Visual Anomaly: A Deductive Prediction Based on an Ethological Model. The Journal of Genetic Psychology, [online] 155(2), pp.219-231. Available at: https://doi.org/10.1080/00221325.1994.9914773.
Feingold, A. (1994). Gender differences in personality: A meta-analysis. Psychological Bulletin, [online] 116(3), pp.429-456. Available at: http://dx.doi.org/10.1037/0033-2909.116.3.429.
Some earlier Sex Differences episodes: