Popular views about gender influence everything, from how we dress our babies to who sits in the boardroom. The only problem is much of what we understand to be true about gender is not supported by science. Melbourne University academic Cordelia Fine dismantles the many myths about gender in her new book, Testosterone Rex, including the following five:
Myth 1: Sex is binary
Everyone is either a man or a woman, right? Wrong!
The popular understanding is that all humans are neatly divided into two sexes: one with female genitals and XX chromosomes, the other with male genitals and XY chromosomes. While it’s true that most of the population fit into either category, a “small but significant percentage” do not.
There are a “few people in a hundred whose genes, gonads and genitals don’t all neatly align on either the male or female side,” writes Fine, who cites biologist Anne Fausto-Sterling’s observation that “there are actually half a dozen or so sexes.”
Myth 2: Men are promiscuous, women prefer monogamy
The idea that men are programmed to sow their seed far and wide while women desire the stability of one partner is an old one. Promiscuity, so it goes, is an evolutionary impulse caused by men’s vast reproductive potential. Sperm is cheap, eggs are expensive. One man, it is claimed, could produce as many as 100 babies in a single year, while an average woman with no access to birth control could produce 15 offspring in her lifetime.
This concept of sexual behaviour doesn’t stack up. Taking into account things like the availability of fertile women and probability of conception (around three per cent a pop), Fine calculates that a man is more likely to be hit by a meteorite than sire 100 children in 12 months, making it unlikely that reproduction-fuelled promiscuity has become a dominant adaptive trait among human males.
Sexual decision-making among humans today has more to do with social factors than with evolutionary biology.
The philandering male/chaste female trope does not reflect the complexity of human sexuality. Just as many men would rather a relationship than casual sex, and there are countless examples of female promiscuity among both humans and the animal world. Sexual decision-making among humans today has more to do with social factors than with evolutionary biology.
Myth 3: Men are from Mars, women are from Venus
Then there is the notion that men and women possess essentially different natures. This outdated view argues that a “prenatal gush” of testosterone creates a distinctly male brain, and in its absence, a female one. These brains, hardwired differently, leave women unable to read maps and men unable to emote.
Today, Fine writes, sexual differentiation of the brain is understood differently, as an “untidily interactive process, in which multiple factors - genetic, hormonal, environmental, epigenetic - all act and interact to affect how sex shapes the entire brain”.
Small sex differences are evident in the brain, but there are no clear links between specific brain features and behaviour. While sex does matter in brain development, Fine writes, it is not the basic, determining factor for the reproductive system.
Myth 4: Boys will be boys
The much-quoted epithet ‘boys will be boys’ is frequently trotted out to explain aggressive behaviour in males of all ages. It assumes that hormones – in this case testosterone – directly cause behaviour. Not true, writes Fine. Much of the behaviour we attribute to hormones is social in origin.
Fish tell an interesting story. In the past, the typically masculine behaviour displayed by male cichlid fish has been attributed to high levels of testosterone. However new research has found that it isn't testosterone that directs the male fish’s behaviour, it’s social conditions.
“Whether a male develops into a dominant fish… depends on his social situation and real estate conditions,” writes Fine. “A fish placed in a tank with a smaller fish will become dominant, a fish without breeding territory will remain subordinate, and hormones will follow. Cichlid fish testes are a social construction.”
Other studies of different species – humans included - have made similar findings. It’s often social context that affects hormone levels, not the other way around. Behaviour that is considered ‘testosterone-fuelled’ could be better described as ‘testosterone fuelling’, writes Fine.
Myth 5: Men don’t have the right hormones for taking care of babies
Childcare is seen as a traditionally feminine pursuit. Testosterone-rich men, capable in many other areas of life, are somehow inferior when it comes to looking after children. Hunting and mowing the lawn they can manage. Changing nappies – too difficult.
But high levels of testosterone do not preclude men from taking on care-giving roles. Male rats, who do not typically care for infants, will “mother” pups in the absence of females. In humans, fatherhood has been shown to affect testosterone levels. The more time a father spends caring for an infant, the lower his level of testosterone. This is not because lower-testosterone men were more likely to be nurturing fathers, writes Fine. Rather “intimate care-giving itself lowered testosterone”.
One experiment illustrating this principle, as published in the book, required men to care for a crying doll. The testosterone levels of men who were unable to quiet the (pre-programmed) doll, or were unresponsive to it, remained unaffected. In men who successfully stopped the crying, testosterone levels were lower. It was their ability to deal with the situation, rather than the stimulus, that was the significant factor in determining their testosterone levels.
“Consider the fact that, outside the laboratory, the confidence and experience a person brings to the challenge of a crying baby is likely to be shaped by gendered expectations and experiences around childcare,” writes Fine. “Claims that men don’t have ‘the right hormones’ for taking care of babies are cast in a whole new light.”
Love the story? Follow the author here: Twitter @nicoheath