I blame it on the collard greens. While we're pointing fingers, I blame it on a recipe for black-eyed pea collard rolls. Don't get me wrong, the rolls were delicious. But the recipe led to the purchase of a small tub's worth of collard greens, initiating a week of giant leaves: steamed, sliced, diced, wrapped, and rolled. It was towards the end of that week that I spotted the Darmera peltata growing on the side of the road.
The leaves were jagged and glossy, dinosaur-sized cilantro. For all I knew they were poisonous, or tasted of bitter card stock. But my first thought as I walked down the street, collards still working their way through my small intestines, was "food."
Yes, this is a confession.
I confess to an alarming appetite for greens. I confess to coveting plants beyond the sanctity of the produce aisle. I confess to a newfound fascination with roadside planters, with median strips and with landscaping. My better judgment prevents me from a spree through the overgrown gardens of Berkeley, pruning the salvias and nibbling on succulents, but it's a fine line between Swiss chard and the neighbor's Verbascum longifolium.
Explaining my condition requires a bit of autobiography — some highlights on the road from omnivore to herbivore. It also requires a brief detour through the psychology of food, a topic often neglected despite our national obsession with dieting and the politics of food.
Global warming, widespread obesity and concerns about sustainability have upgraded food decisions to the moral realm for growing numbers of people. But few appreciate the primitive commingling of palate and principles, the silent mechanisms that establish the boundaries of food.
The distinction between "food" and "non-food" is one we typically take for granted. Your typical 21st century adult can sort corn flakes, broccoli and almonds into one pile, and magazines, assorted plastic and batteries into another. But our evolutionary ancestors didn't have it so easy; food didn't come with labels in the savannah.
Humans are a generalist species, adapted to eating a wide variety of different foods. The ability to extract nutritional value from diverse sources has virtues, but it also has risks. Plant foods can be riddled with toxins; meat with dangerous pathogens. Our ancestors faced a more basic version of the same question we ask ourselves each day: what to eat?
So how do we decide what's chewed and what's eschewed? Other than a penchant for sweets, humans come to the world with food preferences remarkably unformed. Nature endows the notoriously picky Koala with a life-long passion for eucalyptus. But our diet is largely the product of experience. Fortunately we have more than our own experience to guide us: we have the accumulated wisdom of those around us. A rat's food preferences are guided by the choices of others, and human children are no less receptive to the social transmission of what counts as food.
Some items have an easier time making it into the food category than others.
When it comes to meat, humans are conservative. The default is not to eat what you don't see eaten by others. As a result, Americans see dogs and cats as non-food, while no-less sentient pigs and cows grace many households on the dinner plate. Most Americans wrinkle their noses at the thought of eating ears, but ears compete with brains and tongue as a taco filling at street vendors popular in Mexico. And if some animal or animal product is seen as non-food, the thought of eating it is disgusting.
Consider the difference between finding a marble and finding a dead cockroach in your half-eaten salad. You might be relieved to learn the marble was sterilized before joining the arugula. But learning the same thing about the dead cockroach wouldn't do much to ease your disgust. Not everything we reject as food is seen as disgusting, but among potential foods — and in particular among animal products — disgust patrols the border between food and non-food.
After becoming vegetarian about 15 years ago, some of the items I had previously regarded as "food" became non-food. Within a year, meat had ceased to be food, and the idea of eating animals had reverted to its default status: disgusting. Initially I felt disgust only when directly confronted with meat preparation, but this gradually spread to anything in direct contact with meat. In terms of immediate, visceral reaction, finding a piece of chicken in my salad was not so different from finding the cockroach.
Many vegetarians I've spoken with report the same experience, and research confirms we're not alone. Interestingly, it's the moral commitments behind vegetarianism, and not merely abstention from meat, that retrains the appetites and summons disgust.
In a clever study by Rozin and colleagues at the University of Pennsylvania, vegetarians for ethical reasons were compared with vegetarians for health reasons. The findings suggested that the former group found meat more disgusting, and there's evidence to suggest that this was the result and not the cause of their decision to embrace ethical vegetarianism. (Ethical vegetarians did not necessarily report the taste of meat disgusting, which helps explain the popularity of fake meat products.) The upshot: it's committing to vegetarianism for ethical reasons that leads to meat-induced disgust.
When I transitioned to veganism a few years ago, food and non-food shifted once again. In the first few months, I was dazzled by the diversity of food still open to me. I discovered new grains, rare vegetables, exotic spices and new techniques for food preparation. On the flip side, the universe of non-food items grew to encompass milk, butter and other animal products. Eggs and cheese joined chicken and cockroaches on the blacklist for my salad.
As the boundary of "food" restricted its embrace to plants (and the occasional fungi), I developed a newfound appreciation for greens. I admired the beautiful bunches of collards and kale and chard, wrapped like bouquets at the farmer's market. And I fancied the luscious Darmera peltata by the side of the road, leaves beckoning in the wind. Which brings us, at last, to my present condition: voracious herbivore with leafy tendencies.
Call me eccentric for salivating at median strips, but really, what could be more reasonable than recognizing the kinship between decorative plants and the salad bar on the one hand, and human and non-human animals on the other? Becoming vegan makes you a reader of ingredient labels, and as such you realize that the path from soil to snack can be an indirect one. Look closely, though, and you'll see the corn behind the xanthan gum and the roots and sunflowers behind inulin.
Fortunately my peculiar fondness for inappropriate greens seems to be a personal quirk, and not a general condition induced by plant-based dining. This is a good thing. If veganism flourishes in the years to come (and I hope it does), the landscaping will still be safe, and the animals and planet will be safer.
You can keep up with more of what Tania Lombrozo is thinking on Twitter: @TaniaLombrozo