Regarding testosterone, yes, this is indeed a trait that affects sperm mobility and fertility, which are linked to testosterone levels. This is an important trait that seems to be spreading, suggesting that selection against it is weak. However, this raises the question of whether decreased testosterone is inherently bad or if it is a recent phenomenon tied to our civilization or if it has been happening for a long time, possibly even before Homo sapiens.
I used to believe in the mainstream view that higher testosterone in men was better, that masculine, alpha-male behavior was adaptive and preferred by women. The idea was that women would choose such men and that weak, feminine men were less desirable. This perspective suggests that in a group setting, women would be drawn to the stereotypical alpha male. However, research and real-life experiences contradict this.
For example, in my group of friends, there was a guy who wore glasses and was into photography, the kind you'd call a typical introverted libertarian. Despite being passive and having what’s known as a "dad bod" (chubby and not muscular), he ended up sleeping with most of the women in our social circle. The women approached him, not the other way around.
This prompted me to look into evolutionary biology, and it turns out that women often prefer such men. These men might even be more sexually attractive than heavily muscled, high-testosterone men. Consider that women generally aren’t interested in bodybuilders or competitions like Mr. Olympia. This preference has deep evolutionary roots.
Our ancestors evolved from gorilla-like beings with pronounced sexual dimorphism, where males had large canines and muscular builds due to aggressive hierarchies. Over time, as dimorphism decreased, so did these extreme masculine traits. Testosterone and aggressive masculinity started to become less advantageous. This trend may have led to our evolution towards monogamy and the civilization we have today.
Furthermore, this shift could be beneficial. It may explain why chimpanzees, with their strong sexual dimorphism and hierarchical aggression, didn’t evolve the way humans did. Reducing testosterone might preserve cognitive plasticity, allowing for extended learning periods and more adaptable behavior.
For women, choosing less aggressive, more cooperative men has advantages. Human offspring require significant parental investment, and a reliable partner is more valuable than one with merely strong genes. Unlike some animals where alpha males dominate, human society values cooperative parenting, influenced significantly by female choice.
Ultimately, whether one aims to be attractive to men or women, it’s worth considering these evolutionary and social dynamics and what price one is willing to pay for certain traits.
