I was standing in the checkout line at the grocery story with one of my sons who was young at the time. As I was unloading the cart onto the belt, I looked over at my son who was staring at a magazine cover. I certainly don’t expect much in the way of morality from tabloids, but the one that my son was looking at had a particularly revealing image of a woman on the front. Trying to play it cool and not make the incident worse than it had to be, I patted him on the shoulder and said, “Look at this toy over here, pretty neat, huh?” My son didn’t move. In fact, like a deer glued to the headlights of a car, he was motionless in front of the magazine rack.

“Is she a mommy?” he asked, looking at the busty figure.

Oh boy. How do I respond to that? I patted him on the back again and said a bit more forcefully, “Come on bud, let’s not look at that.” But he didn’t budge—totally frozen to the floor. This time I grabbed his shoulder and started pulling him away and tried to explain how we shouldn’t look at that kind of thing. And as I was dragging him from the tabloid he just stared at the magazine and said, not in a voice of defiance, but of pitiful sadness, “But I want to look!”

While I was struck with how honest and open my child was being, I couldn’t help but wonder what was going on under the surface. Where did that come from? Why was my son—who normally couldn’t sit still if his life had depended on it—standing there in a catatonic state of visual consumption? What I now know is that he was encountering something that all adult men intuitively come to experience; my son was seeing something that was visually stimulating coupled with a sensation of testosterone. This surge of hormone—which men experience at a rate tenfold that of women throughout their lives—pulled him toward the tabloid stand. And much like a game of tug of war at a family reunion, he was caught between a dad who wanted him to look away and a body that wanted to stay right where it was.

He was far too young, but if he only knew the destructive power that those images can bring and where his urges came from then he could more easily reorient his actions toward healthier—and holier—living. Is simply having knowledge about where we come from a perfect shield from sin? Of course not. But one first has to know where they come from before they can get to where they want to go.

Knowledge Is Power to Change

An essential benefit of adopting an integrative understanding of evolutionary theory and our Christian faith is that we become better able to recognize who we are and why we tend to have certain behaviors. And this knowledge of our biological and environmental pasts may actually lead us to becoming more whole—and holier—individuals.

Not long ago I was at the doctor for a regular checkup and he noticed a weird blemish on my skin. He started to ask mild questions that became more and more serious as the conversation went on: “Have you noticed this spot on your back changing?”

“Yeah, I guess so.”

“How long has the spot been there?”

“Uh, I don’t know.” (I’m terrible at caring about my health). Then I noticed the questions began to change.

“Is there a history of cancer in your family?”

“Well, I guess so. My brother had melanoma on his leg.”

“Matt,” my doctor said, “Why didn’t you tell me that from the beginning?”

What I wasn’t aware of at the time, but I am painfully aware of now, is that my family’s medical history—not just mine, but my relatives’ and ancestors’—really mattered for assessing current problems in my health. Thankfully, everything worked out fine, but this interaction with my doctor was a tangible example to me of how important is my past. When we come to have knowledge of our roots, we come to have knowledge of our current situation. When thinking of how our ancestry affects our lives today, evolutionary biologist David Sloan Wilson—in his book, Evolution for Everyone: How Darwin's Theory Can Change the Way We Think about Our Lives (Delta, 2007)—observes:

Our unique attributes evolved over a period of roughly 6 million years. They represent modifications of great ape attributes that are roughly 10 million years old, primate attributes that are roughly 55 million years old, mammalian attributes that are roughly 245 million years old, vertebrate attributes that are roughly 600 million years old, and attributes of nucleated cells that are perhaps 1,500 million years old. If you think it is unnecessary to go that far back in the tree of life to understand our own attributes, consider the humbling fact that we share with nematodes (tiny wormlike creatures) the same gene that controls appetite. At most, our unique attributes are like an addition onto a vast multiroom mansion. It is sheer hubris to think that we can ignore all but the newest room. (70)

If we indeed come from a long history of ancestors—some of whom include animals that, right now, seem very distant to us—then just as a medical doctor might ask us if cancer runs in our family, we might ask questions about behavioral traits that run in our lineage. In a strange but understandable way, it actually matters what the nematode appetite was like. It matters that our hunter-gatherer male relatives had frequent sex and abandoned families in search of more mates. And it matters that our ancient female relatives decided to feed their offspring at the expense of other hungry children. Thus, a major step in developing a vibrant Christian life is recognizing that our biological and environmental proclivities that express themselves in negative and positive ways are steeped in our ancestral history.

Michael Dowd, author of Thank God for Evolution! How the Marriage of Science and Religion Will Transform Your Life and Our World (Council Oak, 2007), has a helpful way of presenting why understanding our roots and teaching it to our children is of the utmost importance for Christian development. Dowd discusses his idea of mismatched instincts—the concept where one’s natural tendencies don’t align with modern life—coupled with what evolutionary psychologist Deirdre Barrett calls supernormal stimuli—the notion of unnatural and exaggerated temptations (Supernormal Stimuli: How Primal Urges Overran Their Evolutionary Purpose [Norton, 2010]). Together, this is what Dowd and Barrett are saying: Many of our instincts, from the desire to eat to the drive to have sex, were incredibly important to our ancestors—both human and pre-human. It’s because of those instincts that we are alive today. We should be thankful for them.

Sometimes I remind my classes, most of which are made up by nineteen- to twenty-one-year-olds, that they should be thankful that their grandparents got frisky forty years before they were born. When I make that pronouncement, their reaction is unanimous: “Ahh, Dr. Hill, we don’t want to think about that!” If I’m being honest, half of the reason I say it is to get that reaction. The other half is that I’m very serious. If our grandparents didn’t have a strong libido, we wouldn’t be alive today to be disgusted at the thought of their sex drive. Those drives and desires, from base urges to complex inclinations, are what fueled human development and allowed us to out-compete other organisms who didn’t possess the same instincts. In other words, the ancestors of those who didn’t want to eat all the time and have sex all the time are not here to tell their story. Humans, by cultivating some proclivities from natural selection, can develop a practice of restraint. Here I use food and sex as main examples because they are, quite obviously, two drives that are common and prominent among us. Indeed, there are a host of other instinctual drives we could also discuss, be it feelings of empathy, acts of altruism or self-preservation, and violence.

While it’s obvious that we have these instincts, sometimes they seem out of place given contemporary circumstances. For instance, child mortality rates have plummeted in just the last 150 years, making unnecessary, from a reproductive standpoint, the need to conceive as often as possible. Yet this doesn’t mean that the incessant drive to try to conceive a child has gone away. It’s like a retired race car driver who—still recalling the days when he needed a powerful engine for racing—drives around his block in his Bugatti. The desire to race is still part of his identity, but the need to race has long passed.

While not all drives that we have are antiquated like this—as some evolutionary drives are positive in nature, even today—the same logic applies to the consumption of food today. While famines and starvation are very real for many people in the Majority World—a concern we ought not overlook—most of the problem with contemporary hunger has to do with food distribution not food shortages. Humankind is producing an amount of food that far surpasses what history has seen before. A few hundred years ago, people had to be able to retain fat so that when winter or droughts came, they wouldn’t become emaciated or starve. Today we have immense storage structures and methods to protect against this threat. Before modern advances in agriculture, our food storage was put away in our stomachs, waists, and thighs. In other words, being able to get “fat for the winter” was a real thing. Now we just get fat.

It cannot be overstated that the instincts of Homo sapiens who were living ages ago were incredibly necessary in helping us survive to reproductive age. But now, in the twenty-first century, many of these instincts are mismatched, given advances in human technology, agriculture, and medicine. We simply don’t need to eat all the time or have sex all the time. As a result of such changes, there is now a need for temperate behavior—a behavior that, in an ironic way, does not come naturally to us.

Fries are the Pornography of Food

Many of our mismatched instincts, when combined with supernormal stimuli, are a recipe for moral and spiritual disaster—i.e., for unholiness. If you’re wondering what Barrett means by “supernormal stimuli,” let me explain it with an example.

Burger King french fries are the pornography of food. Here’s what I mean: Have you ever walked by a room where someone was cooking bacon? It’s absolutely irresistible. You start salivating and looking around to figure out where the smell is coming from. There are good reasons for this. Bacon is high in protein and fat and has the calories to provide energy for a long time. And our ancestors were selected after generations had lived and died for such sustenance. So, in a sense, we are hardwired to love fatty foods. We’re almost—and this word is important—imprisoned by fatty foods. And Burger King french fries are our food-warden. I remember when my friend and I were sixteen years old and Burger King had just put out a new style of french fries. They figured out something about evolution and capitalized on it. Instead of having more potato as their new ingredient, they had more oil and fat—a nearly irresistible temptation to our sixteen-year-old instincts. They capitalized on the fact that we were hardwired to search after fat, salt, and sugar.

I say that french fries are the pornography of food because both fries and pornography work on similar human desires. French fries are food-like substances that are ultimately unhealthy for us; pornography is a sex-like icon that is likewise unhealthy for us. French fries have all the glamorous and seductive parts of food—the fat, the salt, the sugar—but none of the substance that provides long lasting enjoyment or health. Pornography, in much the same way, possesses the glamorous and seductive aspects of a sexual relationship, but is at its core shallow and vapid—it is neither sex nor a relationship. It shouldn’t surprise us then that both french fries and pornography are highly addictive. As a pastor and a professor working with college students, I can’t tell you how many times I have had to counsel people who have dependencies on food or pornography. Whether it be health complications or broken families, the supernormal stimuli that contemporary humankind faces are very destructive.

Remember, these supernormal stimuli are just that: supernormal. They aren’t “natural.” They’re conjured up in a lab full of people who know how to manipulate in us these ancient but no longer necessary proclivities. Advertising agencies know that Homo sapiens have evolved to desire copious amounts of sex and be attracted to visual stimuli. So sex is used to sell everything from blue jeans to bicycles. The fast-food industry knows that Homo sapiens have needed fat, salt, and sugar to survive—that we fall into a kind of trance when we smell bacon or fries—so they sell food products that are nearly irresistible. Humans are in a predicament. We exist in a world in which we encounter both our mismatched instincts from ages ago and the supernormal stimuli of the twenty-first century. Deirdre Barrett expresses the problem in this way:

The most dangerous aspect of our modern diet arises from our ability to refine food. This is the link to drug, alcohol, and tobacco addictions. Coca doesn’t give South American Indians health problems when they brew or chew it. No one’s ruined his life eating poppy seeds. When grapes and grains were fermented lightly and occasionally, they presented a healthy pleasure, not a hazard. Salt, fat, sugar, and starch are not harmful in their natural contexts. It’s our modern ability to concentrate things like cocaine, heroin, alcohol—and food components—that turns them into a menace that our body is hardwired to crave. (Waistland: A (R)Evolutionary View of Our Weight and Fitness Crisis [Norton, 2007], 26)

See, our problem is a chimera of sorts—a Greek mythical multi-faceted creature composed of mismatched instincts combine with supernormal stimuli. It is a cocktail of temptation unprecedented in humankind’s history. This chimera is difficult to combat, and—besides contributing to our gluttony, lust, self-indulgence, and other negative proclivities—it leads us to develop habits in our lives that pull us away from Christian virtues, from holy living. But combat it we must, and the more we learn about where we come from, the more we are able to do so. We believe God’s Spirit dwells with us, that we can be transformed and renewed; we can become better than we are. We are not prisoners to our instincts, no matter how strong negative instincts seem to be.