Carol Hoevenan evolutionary biologist and expert on TestosteroneHe devoted his career to investigating how this hormone affects biological and behavioral differences between men and women.
In conversation with Peter Attia For podcast driveHoven analyzed the mechanisms of sexual differentiation and the social and cultural implications to understand or deny these facts.
Hoffen reported in drive podcast that her interest in testosterone and sexual differences stemmed from growing up with three older brothers and noticing different behavioral patterns between them and her.
This interest expanded through travel and observing how different cultures construct sexual roles. Your experience Study chimpanzees In Uganda He ended up directing it towards evolutionary biology, where he saw that the sex differences in these animals, especially in energy and aggression, were similar to human differences.
For an evolutionary biologist, Testosterone forms the explanatory link between humans, chimpanzees, and other mammals: “Males have much higher levels than females, and this helps understand why the sexes are different.”
Hoven stressed that in humans, Sex determination depends on chromosomesalthough gender is not defined only by them. “What really determines sex is the type of gametes the organism is designed to produce.He explained: sperm or egg.
He described the embryonic process: “Until the fifth or sixth week, XX and XY embryos are almost identical. The SRY gene located on the Y chromosome leads to the differentiation of gonads into the testes.Which then produces testosterone.
The hormone that is manufactured by Leydig cellspromotes the development of male internal ducts and, through the enzyme 5-alpha reductase, is converted into Dihydrotestosterone (DHT)necessary to remind the external genital organs.
“Without DHT, an XY individual could be born with female external genitalia; However, upon puberty he will develop male characteristics Hoven explained that these cases allow us to understand the impact of small genetic mutations.
From an evolutionary point of view, he said:Testosterone regulates neural development and sex differentiationThis explains why boys and girls are not equal.” Although hormone levels in early childhood are similar, Behavioral differences arise from exposure to prenatal hormones during critical stages of development.
“Children tend to play more Surprising and competitiveWhile girls prefer games Focused on care“, said the biologist, emphasizing the biological root of these trends, which are also observed in other mammals, but making it clear Socialization and environment can be modified.
Regarding aggression, he distinguished between male and female types: “Men tend to have more Direct and physicalWhile women appear Indirect aggression, such as social exclusion or shaming“.
He mentioned that Men are overrepresented in violent crimesBut female aggression is not necessarily less harmful, but rather manifests itself in other ways.
Hoven thought about the interaction between the modern environment and ancestral motivations. “We were designed to seek out caloric foods and compete for status, but today these drives can become maladaptive,” he explained in his book. drive Podcast.
He noted that male aggression is sometimes channeled through sports and ritual contests. “Men tend to look for specific achievements and invest hours in mastering skills, as happens in sports. This reflects evolutionary adaptation related to competition for resources and mates.“, suit.
Regarding culture, beware of this Denying biological differences Gender creates consequences that must be addressed with evidence and empathy. “Culture can amplify or weaken biological tendencies, but it cannot completely eliminate them,” Hoven defended.
Hoven shared her experience after surgical menopause, which prompted her to start hormone therapy. “Everything changed after the surgery: my hair fell out, my libido disappeared. Even with the decrease in hormone levels, the effect was enormous,” he said.
Currently, use Testosterone, estrogen and progesteroneIt is believed that the treatment improved his health condition in combination with Strength training. “My personal experience has shown me the true impact of hormones on health,” he said.
Regarding hormone replacement therapy in men, he warned of the danger of its use in young men and the need for regulation: Testosterone can be addictive and permanently affect fertility, especially at a young age.. He stressed the importance of evaluating each case individually and prioritizing non-pharmacological approaches when possible.
Biologist They expressed concern about narratives that deny biological differences And to reduce the value of masculinity. “I am writing a book about masculinity and the consequences of denying sexual differences,” he said.
He also warned of the crisis of masculinity and the decline of men in areas such as education, which requires an integrated analysis between biology and culture. “If we think that men and women are equally interested in all areas, we ignore real differences with social implications,” he said.
He defended the need for discussion Knowledgeable and compassionate: “Biology is not fate. Variation is enormous and it is completely normal not to be typical of your species. Understanding science helps to accept diversity and face reality with empathy“.