Rowena's and Sarah's posts brought up some interesting points about gender, sex and culture - no, not those points - and started me thinking. Those who haven't already run screaming may wish to stay to find out what I'm thinking about.
See, there are a whole lot of misconceptions about the differences between human male and human female, from - at one extreme - there being no more difference than whether it's an innie or and outie, all the way through the spectrum to the toxic notion that one gender or the other isn't fully human. Being presented with either pile of bovine excrement hits my hot buttons so hard I start shredding before I've settled on a target, usually with the sarcasmometer pegged out and ready to explode.
Starting with the uber-basics: at conception, the successful sperm is carrying either an X chromosome or a Y chromosome (yes, this is a very large simplification and doesn't include things like XXY, triple X, chimerism and the like. I'm trying to keep it simple). Eggs are always X chromosome. If the sperm has an X chromosome, if nothing goes wrong that egg will grow into a girl. If the sperm has a Y chromosome, the egg grows into a boy.
Each chromosome type (X or Y) carries a whole bunch of information that gets used as something rather like the 'recipe' for boys (Y) or girls (X). It's not as simple as "snails and puppydog tails" or "sugar and spice and all things nice" - it's more like sensitivity to certain hormones (males are relatively less sensitive to changes in the level of estrogens and progesterones, where females are relatively less sensitive to changing testosterone levels), skeletal development (female hip bone structure is quite different from the male version, partly to accommodate the requirement that the female incubate the offspring for 9 - 10 months and partly to lower the center of balance so those big fleshy bumps higher up don't cause problems. No, that's not why those changes happened - they happened because the females with them survived to have kids with them). Sex organs are involved, of course - the aforementioned innies and outies plus all the supporting tackle, and - probably the most influential when it comes to sexual differentiation - brain structure and chemistry.
That's right. Male and female brains are structured differently, and their brain fluid contains a different chemical mix. Obviously it's not a simple either/or thing - it's more that there are two partially overlapping normal distributions, one male, one female. The overlap is where the most effeminate men and least feminine women can be found.
Here's where things get fun: it's a known fact that psychotropic drugs alter brain chemistry. That's why they're used - they're a kind of blunt instrument to temporarily correct maladjusted brain chemistry (yes, even the illegal drugs. It's complicated, so I'm not touching that particular aspect of drugs expect to say that I personally take several prescribed psychotropic drugs and I know people who've found that they don't want or need the illegal drugs once diagnosed and prescribed legal ones. Of course, the plural of anecdote is not data, nor is it knowledge). There's also a whole lot of evidence that non-psychotropic drugs do the same thing: if it can cross the blood-brain barrier, it can affect brain chemistry, and therefore mood and how people think.
Given that, it's simple logic that male thought processes are different than female thought processes. The different balance of estrogens, progesterones, and testosterones alone would be enough to explain that. Even without any cultural programming, you'd get differences.
It's also well-established fact - and taught as such in every teacher ed class I know about (mostly in Australia, about 20 years ago) - that male and female development rates are different. Girls usually learn language and social skills before boys, and boys usually learn math and spatial skills before girls. Again, it's well-established that an early differentiation usually leads to a much larger differentiation later, so it's not exactly surprising that males tend to show a much greater preference and ability with physical, spatial skill sets, where females tend more towards social and verbal skill sets.
Where does that translate to Rowena's observation that college-age young men are disinterested to hostile about whether movies and games misrepresent women, or young women being reluctant to raise any kind of concerns about how women are represented? I don't think it's systemic gender-based discrimination - it's more a function of the differences in thinking styles and the prevailing culture - which in Australia is strongly biased towards stoic acceptance, not whining or complaining, and 'making do'. And culture, as the saying goes, tends to change one funeral at a time.
To start with, at college age, young males haven't finished developing yet (neither have young females). They're still trying out techniques for dealing with the rest of the world, and hostile to anything not 'of the tribe' - which at that age is the same sex, similar age bracket, and similar interests. The opposite sex is undiscovered, unconquered, and possibly dangerous despite the exploratory forays not causing anything more than a temporary limpness. Males that age are also typically anxious to prove that they're adults, and to prove their masculinity (this is one of the reason teens and early twenties is such an obnoxious age). Young females do something similar, although there the emphasis is more on belonging and on being more equal than others. The teen-girl-collective is a terrifying thing, especially from the outside.
An evolutionary digression here: evolutionary psychology has got itself a bad name because of the very human tendency to wrap everything into stories (which itself is a function of the damn near universal pattern recognition ability - predators that were better able to distinguish easy prey from dangerous prey, other predators, or stuff they couldn't eat were more likely to survive and pass that ability to their offspring. Prey animals that were better able to recognize nutritious food and distinguish approaching predators from everything else were more likely to survive and pass the ability to their offspring. It doesn't take many generations for abilities that make surviving more likely to become damn near universal). Stories are effectively uber-patterns that make it much easier to pass on knowledge - which in turn makes the recipient more likely to survive and pass their abilities and stories on to their offspring.
The thing to remember about evolution of any type is that there's no "end goal". What survives and breeds is what's better suited to the environment of the time. Evolutionary psychology seems to be an attempt to understand cultural evolution as compared to physical evolution. Along the way, some interesting aspects of sexual differentiation emerged, and humans being human and intensely interested in sex - instantly hit popular consciousness. Which promptly got a lot of it bass ackwards, not least because the disseminators of the interesting stuff are scientifically illiterate.
Here's the uber-simplified version. Biologically speaking, absent major tech advances women have to carry the babies and then be primary caregiver for a long period of time (up to five years, depending on when and where). That means they're physically vulnerable at the same time as they're protecting the next generation. The physical differences that allow a woman to carry a pregnancy from a microscopic egg to quite a few pounds of baby also reduce strength and speed so that even without pregnancy or children, a woman can't outrun or overpower a man of similar size (and most men will be bigger, because women are also generally smaller than men). If she's pregnant or has a small child to carry with her? Forget it.
So... the females who survived and whose children survived were better than their fellow females at 1) making alliances with other females to share child-watching and predator-watching duties; 2) moving themselves up the female hierarchy so their children had a higher priority than the children of low-status females; and 3) being chosen by a high-status male (which earned them better protection). All of these things take - you guessed it - language and social skills. It doesn't take all that many generations in a dangerous and highly competitive environment (most of them, absent modern technology) before skills like this are the norm, and a female subculture that continuously develops and reinforces those skills has arisen.
Meanwhile, the males who survived and sired lots of offspring were often the biggest, strongest, and best hunters - because while it's possible to live entirely on gathered food, meat packs a much bigger nutritional punch. He who brings home the big steaks has the best fed children, who grow up to be the biggest and strongest and best hunters. The abilities that were advantageous in that situation included mono-focus (the old jokes about men not being able to talk and pee come to mind), spatial awareness, and physical coordination (the latter two sharing a domain space with - ta da! - math).
Big surprise, over generations the mental and physical differences between male and female got more pronounced, and the male and female subcultures moved further apart. Add on the overall culture that evolved around male-female interaction and the local circumstances, fast forward a few thousand generations, and you get where we are today.
In Western cultures there's some reintegration - especially with single-sex schools becoming less common - and traditionally male and female domains no longer exclusive - but the process is a long way from complete and it may never be complete. Those biological differences will always be there.
So, men and women are still very different, and male and female subcultures are still very different from each other, complete with massively different priorities. That's universal - although the rules for interaction between male and female subcultures vary hugely around the world.
Ultimately, men and women are still going to think differently, no matter how close the subcultures get. If we treat that as "discrimination", we're headed for trouble. And yes, being writers we should be using this knowledge. Unfortunately it hasn't found its way to the gatekeepers yet - gatekeepers are like all authorities: they generally belong to the older generation and haven't adjusted to more recent cultural evolution - even when they think they have.
So... we write it, and we stealth it. But if we want to please the ultimate consumer - readers - we need to know what they're seeing when they look at the world. If we can understand it as well, we're more likely to catch their interest and attention.
In short - get the sex right!