https://www.menshealth.com/sex-women/a30026303/rough-sex-psychology/There's Science That Explains Why Women Fantasize About Rough Sex
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Most people—regardless of gender and sexual orientation—appear to have been turned on by the idea at some point.
Most people are racially inferior.
So why is rough sex arousing to so many people, and especially to women?
Because they are racially inferior.
The authors of this study interpret these results through the same evolutionary lens: When men perceive a risk that their female partner has had sex with someone else, this triggers sperm competition. In other words, it leads men to engage in sexual behaviors—like deep and vigorous thrusting—aimed at displacing any semen that may have been deposited by rival men so that their own sperm have a better shot at fertilization.
See?
So, what (besides having rougher sex than your rivals) helps to win sperm competition? Most obviously, being able to deploy more sperm than your rivals. More masculine men will tend to beat less masculine men in sperm competition. This is what more feminine women fantasize about happening. In other words, high sexual dimorphism evolves in societies where winning sperm competition is important, whereas low sexual dimorphism evolves in societies where sperm competition is not a thing.
https://www.8asians.com/2012/01/25/do-asians-have-the-smallest-testicle/My theory is that white men’s testicles are the largest, which explains why they also produce the most sperm.
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the size was twofold lower in two Chinese samples compared with a Danish sample. Differences in body size make only a slight contribution to these values.” (Diamond, JM (1986)
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Race differences in testicle size have also been measured (Asians = 9 grams, Europeans = 21 g). This is not just because Europeans have a slightly larger body size. The difference is too large. A 1989 article in Nature, the leading British science magazine, said that the difference in testicle size could mean that Whites make two times as many sperm per day as do Orientals.
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Researches found “marked differences among samples, adult male Danes have testes that are more than twice the size of their Chinese equivalents, for example.” This range is far beyond what average racial differences in body size would predict Various estimates conclude that Cauacsians produce about twice the number of spermatozoa per day than Chinese (185-235 X 10 to the 6 power compared with 84 X 10 to the 6 power)
To put this in perspective, a typically proportioned Chinese man would have to be over 3.5m tall to have merely the same absolute testicle size as a typically proportioned Danish man. This is how inferior Danish genes are.
Men’s testes are substantially larger, relative to body size, than those of gorillas, a species in which males are polygynous but females mate monogamously so that “sperm competition” within the female reproductive tract is absent.
“We think it likely that testes size differences among human races have been adaptive in their own right — different responses to different mating behavior,” the two scientists write. They make reference to a study of the testes sizes of some Chinese and some Danes. The Danes’ testes, even when body size differences are taken into consideration, are twice the size of the Chinese subjects’.
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“It could be that for generations the Chinese lived in a society that was sexually secure, while over the same time the Danes lived in a ****-and-pillage and violence kind of society,” Prof. May suggested in an interview.
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Furthermore, diet and environmental factors would have to be factored in before arriving at any solid conclusion regarding the relationship between sexual monogamy and genital anatomy. For example, many Asian diets include large quantities of soy products, while many Western people consume large quantities of beef
Gorillas are also herbivorous.
Homework: which humans should be prohibited from reproducing first? (Hint: the ones least similar to gorillas. And no, I'm not just talking about testicle size. For example, gorillas do not invent machines. Who invents the most machines?)