Science of Sex: Why Do Genitals Look Like That?

October 27th, 2018

In this installment of Science of Sex, we take a look at why genitals look the way they do. Surprise: it’s for reproduction. Keep reading if you want to learn a bit more, however.

Originally I was just going to focus on testicles, which are surprisingly more interesting than I had been lead to believe. However, I couldn’t help myself from going down the rabbit hole and touching on other genitals.

Note: The language in this post is cisnormative because I am focusing on reproduction alone.

science of sex - why genitals look that way

Testicles and ovaries are the two types of gonads or reproductive organs; although, the scrotum is more analogous to the labia. Both split down the middle, and the scrotum even has a “seam.”

Anyone who has seen a certain Seinfeld episode is familiar with shrinkage, which occurs when the body is cold, and the genitals retract closer to the body. It’s the cremasteric muscle that’s responsible for pulling in the testicle.

The muscle doesn’t just pull the testicles up and down. Each testicle has its own orbit, so they’ll hang unevenly. Apparently, the right testicle usually hangs higher than the left. Some suggest that this is also a defense mechanism should one testicle become harmed; the other may remain safe. But anatomist Stany Lobo suggests that testicular orbit maximizes space for each testicle, allowing it to remain cool enough.

The current theory is that testicles and the sperm inside them remain slightly cooler than the man’s body by about 3 degrees Celsius (cooler temperatures at night lead to descended scrotums, which may play into why humans so often have sex after dark), but the heat of a woman’s vagina and uterus reactivates the sperm, which are able to survive at those temperatures for the amount of time it would take to fertilize an egg (approximately 50 minutes to 4 hours). Voila!

As best as we can tell, the comparatively-large human penis is designed mostly for pleasure. A larger penis may attract and keep more mates.

The shape of the penis also aids conception. The large, contoured head acts a bit like a shovel as it thrusts into a vagina. This doesn’t necessarily benefit conception by a man’s sperm, but it does displace sperm for any previous partners a woman may have had. A larger corona and more vigorous thrusting can also increase the sperm-displacing effect.

The refractory period prevents a male from re-entering his partner and displacing his own sperm, aiding the continuation of his lineage.

The vagina and uterus are obviously shaped for penile penetration. However, the position of the organs aids reproduction in another way. Before our ancestors walking upright, the uterus tilted to aid “doggy” style sex. When our ancestors did become bipedal, the uterus tilted. One theory posits that to aid face-to-face sex, female lips became more pronounced and darkened in color (mimicking her labia) to attract a mate. I imagine those same characteristics attracted mates to female partners, especially when swollen and darkened due to arousal.

Interestingly, I have yet to come across a lot of information about the shape of the vulva. Perhaps the penis does most of the work when it comes to reproduction. And researchers have yet to come to a conclusion on whether female orgasm aids or hinders conception.

Like the foreskin protects the glans, clitoral foreskin protects the clitoral shaft (which extends deep below the surface). The labia also provide protection for the vagina, which is further protected by the hymen, stretchy tissue around the vaginal opening that can sometimes cover it.

The vagina itself balloons outward during arousal, a process known as vaginal tenting, that makes intercourse easier. The elongation of the vagina reduces penile impact against the cervix, which many women find uncomfortable or painful. No one wants to reproduce if it hurts, after all.

It’s interesting that despite all these adaptations, sex can still be so uncomfortable, especially for women. But perhaps nature’s focus on reproduction is why issues of pleasure, comfort, and connection are so often overlooked.

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The Mysteries of Female Sexuality

April 19th, 2009

The female body, ever mysterious; men have been trying to divine its meaning and function for years to no avail. This fact is often a point of laughter among those who wear said body and a point of frustration among groups of men who share their foibles. Sadly, the mystery of the female body, while alluring, is not one to just the lesser sex (I kid) but to those who have spent their entire life in the body as well.

I can’t tell you the number of times a woman my age has shown ignorance about her own body. Worse yet, woman the age of my mother and grandmother seem to know even less and these are the women who are passing on knowledge to the woman who will come after them. Fortunately, sex and body education is growing increasingly more helpful and accurate but it means not all women have the same information regarding their bodies. Indeed, some women even have inaccurate information which was fed to them as a means of deterring them from sex. They believe their genitals and even their sexuality is something which is dirty and shameful and should be treated with such regard. They are not encouraged to explore or enjoy themselves. They are simply a receptacle for production and while I could never belittle the strength it takes to be a mother, I can also never stress enough how important those same parts and systems are to female sexuality and how beneficial it can be. Thus, it’s no surprise that I do encourage healthy sex education.

I am surprised, however, when I hear from people near my age who still carry with them inaccurate or incomplete sexual information. After all, my own sex education, while not the best ever, seemed to be far ahead of the pack in many aspects. So, when a female peer looks at me in shock when I mention that, yes, females can masturbate, I tend to return just the same look. Why is it that women seem strangers to their own bodies? What is the big gender difference that makes being a man and having a penis more acceptable than being a woman with a vagina?

I think a large portion of our misunderstanding when it comes to the female body is due to the fact that it is simply less accessible than the male body. Whereas males can easily find and manipulate their sexual parts, location and successful stimulation for females can be much more difficult. Consider that there is a generally acceptable mode of masturbation for men but not so much for females; perhaps this is simply due to the fact that it is easier to understand what we can see. After all, fear of the unknown is nothing new to humankind. Our internal parts are not the only ones difficult to spot; even our external genitals are less obvious than those of our male counterparts.

I have read, on multiple occasions, that females should take the time to get to know their body with their eyes. For those of us who are not astounding gymnasts, I would suggest using a small hand or makeup mirror to become more familiar and comfortable with our parts. If a mirror is out of the question, it would also work to take a picture. If you have a digital camera, you can examine and delete it without anyone else discovering it.

However, there’s one big disadvantage to being female and knowing your body well and that is menstruation. While I know there are some women who feel blessed to be female and are ecstatic over menstrual bleeding, I am not one. And I’m not alone in dreading the one week a month when my body seems to want to work against me and my hormones fluctuate without warning.

The drawback to knowing your body is knowing what it can do and not all of those things are pleasant. When bleeding is a prominent component, it’s easy to apply the word “dirty” to female sexuality. Even if no one around us holds those negative attitudes, it’s easy enough to think negatively about ourselves. When you add in moodiness and irritability that menstruation frequently causes, it can easily become a downward spiral and add negative overtones to our sexuality. Shame is only a short step away, especially if those about us enforce those attitudes.

Of course, this alone does not have to be a road block to exploration and understanding of our sexual selves. While I do not relish menstruation, I do not hate my body or sexuality either. If nothing else, I grew tolerant of the way my body worked despite its differences from my male peers.

Those differences can also enforce negative attitudes and the proliferation of false truths about female sexuality. Men and women have always had their differences and only in the recent past has the idea of “different but equal” arose. True, men and women excel in different ways but for too long these differences were seen as irrefutable proof that the male gender exceeded the female gender. These differences were used to control and own people in a way that most would now agree is unethical.

For thousands of years, women were told they could not work outside the home, be members of the military or even vote. For thousands of years, women were taught to be subservient and to please their husbands. Their wants and their needs always coming in second place, if they even placed at all. It took many generations for these ideals to become ingrained in countless societies and I have no doubt it will take just as many generations for new ideals to be adopted, no matter how contemporary we may think ourselves to be.

And these differences? These inequalities? They must exist for a reason. Women must suffer with the “monthly curse” for a reason. Instead of our differences being used to further society, women dealt with the stigma that they were intrinsically inferior to men because of some historic sin (perhaps the forbidden fruit?), rendering them less important, less human than men. Why would they explore these differences when they represent such shame?

At surface level, I am shocked by just how far we have to go in understanding the female body and by association, female sexuality. Still, when I consider all the contributing factors, such as how women have been regarded for thousands of years, the attitudes which have become second nature to us and how our bodies can sometimes feel like our enemies by “hiding” our most sexual parts or bleeding once a month, the mystery begins to unravel. When we see that, we can also see that there is nothing wrong with exploring our bodies and sexuality.

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