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Human Mating and Aggression—An Evolutionary Perspective

1650 words

One of the many oft-repeated statements from feminists is “Who commits over 80 percent of all violent crime?! MEN!!!!” This is true. No one denies this. Is this stark disparity due to biology or culture? Anyone who reads this blog knows the answer to that question, however, a lot of people (mostly feminists and other radical leftists) disagree and, of course, believe that all differences within and between people are explainable by environmental factors.

Men commit 80 percent of all crimes. Feminists may point to this stat and say that men are more dangerous than men, and, for instance, use the crime argument for separation from men the way some people use the black crime argument as a point to argue for separation. It’s clear that people who say these things don’t understand biology, because things such as this are easily explainable.

Men average 270-1,070 ng/dl on average compared to women’s 15-70 ng/dl.This large variation in testosterone between men and women is an indication that the testosterone ‘gap’ (which should be there, biologically speaking) is the main factor in explaining the crime disparities between males and females (Dabbs et al, 1995; Batrinos, 2012).

Testosterone regulates morphological traits which are then sexually selected for (Hillgarth, Ramenofsky and Wingfield, 1997). So, in a way, testosterone itself was being selected for, as it is the mediator of all of the morphological characteristics that make Men men.

These same differences in testosterone between men and women also explain the huge variation in muscle mass and strength between men and women. Muscle mass was, potentially, a way to attract mates. Though muscle mass itself is a sexually selected trait, in terms of natural selection it is a negative. This is because the more muscle mass you have, the more calories you need to consume. Men have 61 percent more upper body strength than women and 75 percent more arm mass, which translates to 90 percent greater upper body strength in men. 99.9 percent of females fall below the male mean here, which is to be expected with what we know about anatomy and physiology in regards to the human sexes. The effect was almost as large when it came to lower body mass, with men having 50 percent more muscle mass while being 65 percent stronger than women (Lassek and Gaulin, 2009). Muscle mass is also a feature in men that gets sexually selected for (Puts, 2016)

When women are ovulating, they “show a weakness” for men with “good genes” when they are at their most fertile. This shows a causal mechanism through sexual selection for high levels of testosterone to be selected for in men, which then causes the differences in fat-free mass and aggression rates, among other variables. Indeed, we do know that, on average, women want a mate that is successful, good looking, has money, has a desire for home and children, and being a loving partner. Women, obviously, secure a man’s genes when she bears his child. So a woman would always attempt to secure the best combination of these traits in the same man (Buss and Shackelford, 2008). Sexual selection explains sex differences in aggression (Archer, 2009). So, as you can see (evolutionarily speaking), it’s women that are the cause for the so-called aggression that feminists complain about—they sexually selected us for higher levels of aggression and testosterone, then complain about it in the modern world. 

Sexual and natural selection are the causes for increased aggression/testosterone rates in men when compared to women. These traits were clearly advantageous during in our ancestral habitat, as a more aggressive mate would provide better protection and food acquisition. When organisms compete for scarce, nutritious food, mates, and space, competition increases between organisms. This can lead to injury or death (the less-able being naturally selected out of the gene pool); chronically elevated levels of testosterone associated with aggressive competition may suppress the immune system and have negative effects for health and fitness (elevated cortisol levels, which triggers fight or flight is also a negative); it may increase risk of predation since a high testosterone organism won’t notice predators around them; aggressive contests tend to be physically demanding, sapping energy; and it may damage social relationships, for instance if a male is aggressive to a female that male won’t mate and thus get selected out of the gene pool (Georgiev et al, 2013).

A study in Sweden looked at the frequency and how often men committed acts of violent crime compared to women (Trägårdh et al, 2016). They discovered that in the two decades from 1990 to 2010, there were 1,570 cases of deadly violence with men accounting for 1,420 of the cases (90.4 percent) while 150 women committed violent crime (9.6 percent). Women accounted for one-third of crimes committed against children, however, which has its basis in evolutionary psychology as well.

The risk of being killed is highest in your first year of life (Friedman and Resnick, 2007). Why? Infanticide. The mean age that mothers commit filicide at is 29.5 while the mean age of the babe is 3.5 years (Rouge-Maillart et al, 2005). The evolutionary explanation for this is that the mother still has time to conceive more children, so the fitness hit is not too large. Further, women are more likely to commit filicide if they have a second child under the age of 20 (Bourget, Grace, and Whitehurts, 2007). So obviously, the older a woman is the less of a chance there is that filicide will be committed since it would be a fitness hit since older women have less of a chance to conceive children, along with a higher chance for the child to have birth defects (Stein and Susser, 2000; Lampinen, Vehviläinen-Julkunen and Kankkunen, 2009; Jolly et al, 2000). So from an evolutionary perspective, it doesn’t make sense for a woman to kill her child if she’s about to hit the age-40 wall (Reproductive Endocrinology Infertility Committee et al, 2011; O’Reilly-Green and Cohen, 1993; van Katwjk and Peeters, 1998; Yaniv et al, 2010).

Male infanticide is associated with social monogamy in primates; male infanticide may be what causes females to stay and mate with one male (Opie et al, 2013). This is caused by females choosing to stay faithful to mates, which then drives monogamous relationships. Serial and social monogamy is the norm for humans (Brandon, 2016). This, then, goes back to what a woman looks for in a man, and has her want to stay with that one man who has all of the qualities necessary to be a good mate and father.

In sum, when feminists complain about male aggression and crime, there are substantial evolutionary underpinnings behind them. They do not even realize that even when they are fighting for ‘equality’ between the sexes, that they are directly helping our arguments that there are inherent biological, physiological and morphological differences between the sexes—driven by sexual selection—which is then a cause for a large amount of the variation in crime (and other variables) between men and women. These intrinsic differences between men and women are why we are so different from each other.The sexes also differ in the brain. There are numerous biological explanations between differences in aggression between men and women, and they come down to sexual selection and what propagated our species in during our ancestral evolution. A large cause for these differences is mate selection—which would, technically, make women the culprits, as they  selected us for these traits. The fact that these differences are still so profound in modern-day society is not at all surprising.


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