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Agustín Fuentes Ph.D.
Agustín Fuentes Ph.D.

Why Is Sex So Complicated?

Humans have a distinctive, messy, and elaborately cognitive way of having sex.

Sex can lead to fun, fights, babies, break-ups, make-ups and sometimes even disease. Why is a basic biological behavior like sex so complicated for humans? Is that just part of our nature?

Well, yes and no. Sex is complicated for nearly all organisms that engage in it, but “sex” in humans is not exactly the same as sex in other organisms. For humans sex is not confined to genitals or even to purely physical contact. Human sex can be had in conversation, over the phone, while dancing, over a well cooked meal, in one’s mind, as well as physically between two (or more) people. For humans sex is a seriously complicated and totally biocultural act. It is never just about biological processes, ever.

A bit of evolutionary and anthropological context helps us get a better handle on why sex is so complicated for humans.

Our basic mammalian biology drives us to have sex of some form so we encounter all of the problems (and benefits) other animals have with sex. Our primate history of social sex shows us that we have all the complexities of other organisms coupled with the fact that much of our sexual activity pulls double or triple duty as being a core part of the way we get along (and don’t get along) with each other. But, humans can talk about sex, we can use our big brains to reason through it--does this make it easier to navigate and negotiate? No, but it makes it much more interesting.

The word “sex” at the most basic level just refers to the process wherein two organisms exchange gametes (sperm and egg) for reproduction to occur. But even for the simplest of critters, sex is always more than the tradeoff of gametes. To get to the point where you can exchange gametes you have to begin some form of negotiation. An organism has to navigate the local ecology to find a potential mate, convince the mate to exchange gametes and then, once the exchange is made, it does the best it can to set up another exchange or move along and find another potential mate. All this is done while trying to ensure that searching for, and engaging in, sex does not also make one more likely to be eaten or less likely to find food, encounter dangerous diseases, or expend so much energy such that one keels over after (or during ) the sex itself.

So, even for the simplest animals, sex is more than an act, it is a series of events and negotiations with hard to predict results. However, it’s also a very good system for producing and maintaining biological variation, the stuff organisms need to keep them in the game of evolution. So in spite of the complications and unpredictability, evolutionary processes have generated a number of physiological systems that ensure that organisms keep seeking sex, even when it seems a little precarious to do so.

Since we are naturally interested in humans, we can move along to the other primates as a comparison closer to home (in an evolutionary sense). It turns out that in many primates sex is not only complicated, it is also frequently not associated with reproduction. Many primate species (especially our closer relatives, the apes) use sexual activity as part of their social repertoire. Social sex can make friends, break friends, end fights, start fights, all in addition to the fact that sometimes it also ends up in reproduction. Social sex is an important part of being a primate. It is no wonder that primates have more sexually transmitted infections than most other mammals…they have more sex.

But does this tell us anything about ourselves? About our nature? Yes, it tells us that because we are primates and amongst the most social of the primates, we are evolutionarily saddled with a complicated social system in which sex, beyond the exchange of gametes, is a central part. But wait, it gets even more complex.

The fact that sex can result in offspring is a central feature of our biology, but humans have known how to wiggle around that aspect of sex for a long time… reproduction underlies the physiology of sex, but by no means is it the main influence in most human sexual activity.

Sex for human beings, in addition to being biological and social, is deeply cultural and thus extremely psychological. Every human brings with her or him a suite of embodied experiences to every sexual encounter and even to every thought, consideration, or fantasy about sexual encounters. At a minimal level this includes one’s gender, the current gender expectations of his/her society and all the subdivisions in that society s/he belongs to, personal life history and past experiences and exposure to sexual activity, sexual orientation, and age, health, body image, religion, politics, economics, computer access, etc…

With all of this mess it is amazing we continue participate in, and enjoy, sexual activities…but we most certainly do. This tells us something about human nature: sex is really important in spite of its complexity and potential for social and physiological danger. Why? Because human nature is all about social intercourse, about connection and interaction between people, exchanges of thoughts and feelings, and sex is a central part of this system. Humans have a distinctively complicated, messy and elaborately cognitive way of having sex and that is part of what makes us one of the most adept, complex, and interesting critters on the planet.

About the Author
Agustín Fuentes Ph.D.

Agustín Fuentes, Ph.D, is a professor in the Department of Anthropology at the University of Notre Dame.

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