Evolution and food: it's all in our minds

Posted on October 31, 2018

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Evolution doesn’t necessarily create the best solution; just a solution that allows you to have more kids. In the case of Homo sapiens – us – evolution shaped our minds but left vulnerabilities and quirks that everyone from governments to marketers can exploit.

A case in point is some people’s tendency to fear new foods – particularly those borne of hard-to-understand processes. “Eat nothing your grandmother wouldn’t recognize,” is a mantra in some circles. It’s also a common logical fallacy called the “appeal to antiquity.”

From an evolutionary perspective, this is a perfectly reasonable, perhaps the best, standpoint. It’s safer to eat what you remember eating as a child and more risky to try something new.* Presumably, those bold individuals who tried a bevy of possible new edibles died more often. Their more wary cousins survived to become our ancestors and passed along their native caution to us.

When potatoes were first introduced to Europe from South America, people would have nothing to do with them, rejecting them as unhealthy and even un-Christian (in Russia, they were suspiciously called “the Devil’s apples.”) Perhaps not an unreasonable reaction – potatoes are part of the nightshade family and parts of the plant contain toxic alkaloids. Yet with a little knowledge on how to prepare them, potatoes proved their value and eventually became the fourth largest food crop in the world, after rice, wheat, and corn (another crop from the Americas).

As people became comfortable with new crops, they were not only accepted, but taken for granted. Eventually, they gained the tested-by-tradition stamp of Grandma’s kitchen.

As science progressed, naturalists observed plants and animals and put them into neat slots based on their characteristics. Those able to breed and have viable offspring were put in discrete categories called species. Certainly, there were hybrids such as mules, geeps and ligers, but these were exceptions to what became accepted as the natural order of things.

This setup served humanity well for hundreds of years. Agriculturalists could breed different kinds of sheep to produce varieties with finer wool or wheat with shorter stems and more seeds. Without realizing it, we were practicing a sort of forced evolution: those animals and plants with traits humans wanted got to survive and reproduce.

Then we learned about genetics and everything changed. Plant breeders learned how to “speed up” evolution, using radiation or chemicals to cause changes, or mutations, in DNA, the molecule that stores the chemical blueprints for all life on Earth. Most mutations are either benign or harmful, but some are useful. For example, one set of mutations produced grapefruit with flesh that was pink and sweet rather than yellow and bitter.

Later, humans learned how to take the next step – genetic engineering. Rather than cause a bunch of random mutations and hope for the best, we could identify the genes we were interested in and move only those genes into our target plant or animal. With this method, we created crops that can fight off insect pests all on their own and fish that grow faster, using less feed and energy to grow to market weight.

Of course, people freaked out. Moving genes from bacteria to corn and eggplant? From an ocean pout to an Atlantic salmon? That’s unnatural! (Although, truth be told, cross-species gene transfer happens in nature all the time).

Again, we might blame it on our own evolutionary baggage. Nature is perceived as good, wholesome, familiar. Even natural hazards such as poisonous snakes aren’t terribly scary – we just know to avoid them. But unknown hazards are a different story.

Consider a couple of early Homo erectus out on the African savanna. That rustle in the grass? It might be the wind; it might be a lion. Keep on walking and you might get eaten. Sprint for the nearest tree and climb to safety and the worst that happens is you feel silly for being spooked so easily. But fraidy-cats survive to have kids. We are the descendants of fraidy-cats.

Of course this leaves us vulnerable to savvy activists and marketers that know how to use our fear of the unknown to separate us from our money. “X causes cancer!” “GMOs are bad!” “Vaccines aren’t safe!”

Evolution has shaped our minds and left flaws, but these minds also have the ability to reason. It is this quality that allows us to examine our fears. We can discover if our fears are real or simply imaginary monsters under our beds.

*H/T to James Wong (@botanygeek) for this idea.

Michael Robin
Saskatoon writer