If you’re an orthodontist looking for a new challenge, I recommend you look no further than the dental disaster that is the babirusa. Beauticians, I extend the same chance to prove your skills. Whether it’s a form of wild pig, which it’s currently classified as, or some sort of pig-deer, as its Malaysian name suggests, or is actually a distant relative of the hippopotamus, as some taxonomists believe, one thing we know about the babirusa: it is all ugly. Sporting a pair of fearsome lower tusks for stabbing opponents, and a pair of upward-growing canines that grow through the skin and curve all the way to the eyes, which aid in grappling and butting, the male babirusa’s unique headgear makes it extremely attractive to lady babirusas, and has the opposite effect on everyone else.
The footlong upper tusks are actually quite brittle and exist mainly for show, as they seem correlated with age and testosterone levels. They also provide a handy way to weed out the older babirusas who have too much testosterone.
But it’s not the babirusa’s teeth that make it the subject of today’s post, but its diet. Like a wild boar, the babirusa is an omnivore that is primarily a vegetarian and a frugivore. And like any pig, it enjoys wallowing in mud, as a healthy clay facial keeps it cool in the jungles of Sulawesi, and helps with parasites to boot. (As for the complexion, it does little in this case.) But the babirusa also eats the clay. The act of eating earth is called geophagy, and it’s practiced by many animals, including apes, birds, and elephants. And why would you want to eat dirt?
Zoopharmacognosy. “Zoo” = Animal, “Pharma” = Drug, “Gnosy” = To Know. Zoopharmacognosy is the process of animal self-medication, by which an animal knows to use a certain plant or soil to cure its ailments. In the babirusa’s case, the clay it eats provides it with essential minerals it doesn’t get in its diet, particularly sodium. But it also neutralizes the pH in its three stomachs: by consuming an alkaline soil, the babirusa counteracts the acids and toxins of some of the leaves it eats, allowing it to extend its diet to plants it couldn’t otherwise digest. The babirusa uses clay — and only certain clay at that — the way we use multivitamins and antacid tablets. The wisdom to know to eat one particular clay over another to ease its stomach pains is an inheritance of millenia upon millenia of culture, instinct, and ecological street smarts.
A common and valid argument for biodiversity and conservation is that the wilderness is our pharmacy. Medicines that cure cancer may exist among the undiscovered orchids of the tropical canopy, they say, if only we can find it. And how could we find these elusive chemical compounds on which modern medicine may soon depend? By watching the animals, of course. It’s what we’ve done all along.
Panax pseudoginseng, a plant used to treat bleeding even through the Vietnam War, was supposedly discovered by a Chinese man who beat a snake within an inch of its life, and then watched it heal its wounds by eating the weed’s leaves. Gorillas use ginger for upset stomachs, just as we do. And if you’ve ever warded off mosquitoes with a citronella-based insect repellant, you can thank a monkey. Over a dozen species of monkey rub plants from the Citrus family into their fur to discourage mosquitoes and fleas, as well as other plants with antiseptic, anti-microbial properties to heal stings and bites. Knowledge of these plants is shared among families and troupes, passed down from old to young, the way medicine men and curanderas have passed down their understanding of herbs to daughters and apprentices.
In fact, removal of parasites is one of the primary uses of natural medicine by animals. Starlings will line their nests with wild carrot leaves to prevent mites, and packrats often place bay leaves at the entrance of their middens to deter fleas. In India, house sparrows will line their nests around hatching time with a tree leaf rich in quinine, which not only acts as an insecticide, but treats the symptoms of malaria.
Often, an animal’s best way to repel insects is to use insects themselves. Venezuelan capuchins will rub themselves with centipedes during the rainy season; the centipedes exude a benzoquinone toxin that repels bugs. And most songbirds engage in behavior called “anting,” in which they either rub their feathers with crushed ants, or sit on an anthill and let the ants swarm over them. They are picky about which ants, however: only ants that produce formic acid, the primary ingredient in ant venom, will serve their purpose. It happens that formic acid is also great for killing and repelling feather mites, so much so that it’s worth a few ant stings to get it.
Slightly more difficult to avoid are internal parasites, but animals sometimes prescribe the right medicine for those, too. In 1987, Michael Huffman, one of the first scientists to study zoopharmacognosy, observed a female chimpanzee cure herself of intestinal parasites by ingesting the pith of a Vernonia fruit. By isolating the phenolic compounds in the pith, which were entirely new to biochemistry, he discovered that they contained anti-microbial, anti-parasitic, and anti-tumor properties. Huffman also witnessed chimps cure themselves of worms by eating whole the woolly leaves of a certain plant called Aspilia, which, in addition to its anti-fungal, -parasitic, -bacterial, and -viral compounds, also catch intestinal worms like patches of velcro and take them on a magic carpet ride out of the digestive tract.
Reproductive control is another powerful incentive to self-medicate. Pregnant African elephants will walk for miles to consume the leaves from a particular tree in the Borage family which helps induce labor; native Africans learned by their example, and now use it for the same purpose. Horny Goat Weed, used as an aphrodisiac by horny goats, is now used as an aphrodisiac by horny men. And the muriqui monkeys of Brazil will consume a plant with a compound that mimics estrogen during non-mating seasons, potentially to decrease the risk of pregnancy, and when the season is right, will consume another plant whose compounds mimic progesterone in order to increase fertility.
These are just a few of the many ways in which animals use the pharmacopeia of nature, without the need for doctors or scientists to prescribe corporate drugs. The most interesting part of zoopharmacognosy, for me, is the “gnosy;” how do they know which plants to eat and when? Monkeys may pass their pharmaceutical knowledge down as part of a cultural tradition, but what about bears and coati, which also make their own insect repellent but are generally antisocial animals? How do birds, which do not teach their young which reeds or berries are antimicrobial, know to eat this or line their nests with that?
There’s not much we know for sure, and that means it’s irresponsible conjecture time. I’d wager that the knowledge of local medicine in animals is often instinctual, sharpened by natural selection. Animals with a taste for certain plants stayed healthy, while pickier or unluckier eaters languished, and over time the taste became hereditary and innate. And the force by which the animal came to know to eat a certain food for its health is the phenomenon known as a craving. Or maybe a jonesing. Or maybe…
…a pica. That’s what pregnancy experts call the craving for non-food items. And nobody knows cravings like a pregnant lady. Named for the magpie, Pica pica, which will eat just about anything, the pica phenomenon will extend to a hunger for dirt, ashes, clay, chalk, ice, laundry starch, baking soda, soap, toothpaste, paint chips, plaster, wax, hair, coffee grounds, and even cigarette butts. No one is sure exactly what causes pica, but it’s been suggested that the craving for dirt — geophagy, you’ll remember — is caused by an iron deficiency, or the lack of another mineral in the diet. Your ob/gyn will strongly warn against eating laundry starch and cigarette butts — heck, it’s not healthy to indulge every craving you have for jalapeno poppers, either — but geophagy has been in practice among pregnant women since time immemorial, and science is now figuring out that eating dirt might have benefits for humans similar to the benefits it affords the babirusa.
So while we thin the living medicine cabinets of the forest, forget our tradition of herbal folk remedies, and put our health in the hands of secretive corporations who may not have our best interests in mind, it is comforting to know that humanity may not have entirely lost our instinctual, evolution-born knowledge of medicine. The craving, our body’s way of telling us what we need, can be our bond with the Earth when we know how to properly listen to it.