Once, for four or five weeks, I was a fly nest.
This happened when I was ten years old, during a vacation with my maternal grandparents, on a farm in San Carlos de Alajuela. Those were days of getting up early and milking cows next to spotted horses, small calves and even smaller botfly larvae.
The botfly larva is the Latin American version of Alien: the extraterrestrial with an elongated head that incubates its embryos in the body of those who are unlucky enough to cross its path. In addition to parasitizing cows, bulls, and calves, the botfly larvae of my childhood laid their eggs through other insects on dogs, pigs, and children vacationing with their grandparents.
So when the itching and contortions of barbed wire on my head began, my grandfather cut my hair around the watery hole in my crown, put a tape on it, pressed it, waited a few seconds, and forcefully pulled back the fabric. When I burst into tears, without taking my eyes off the bloody worm writhing on the plaster, my grandfather hugged me and promised me that the next day we would go for ice cream.
We often link flies with disease and rot. It is not strange then that they are monstrous, especially if one came out of our body in the larval stage. At the beginning of the eighties, we fought them with a viscous strip of paper that we hung from the ceiling. The flytrap paper was a massacre that we lived in real time. The way we faced what seemed monstrous to us.
The detective fly
The Forensic Science Department of the Judicial Investigation Agency houses a laboratory for non-human genetics, DNA testing, microscopes, and fly larvae.
John Vargas, the entomologist who directs the Biology section of that department, does not hide his pride when he shows me the bedrooms where his detective larvae sleep.
The process is simple. The smells given off by a decomposing corpse attract the bluish flies of a family with an exuberant name: the caliphorids. Once the eggs are deposited in the body, the larvae begin a cycle that allows the time of death to be calculated. The first record of this alliance appeared in China eight centuries ago, when a judge solved a crime thanks to a fly that landed insistently on the culprit’s weapon.
Half an hour later, in a Caribbean restaurant, John tells me that the main pollinators of the cocoa flower are tiny flies. In other words, without their work, we would not have chocolate. He also mentions that, within a few years, the black soldier fly could be a superfood and an ecological fuel. Very few, besides John, could justly claim the title of Lord of the Flies.
Later, over coffee, he discusses a medical treatment that cleans wounds and stimulates the growth of healthy tissue through the use of sterile larvae of the fly Lucilia sericata. The cinema had told us something about this, in that scene in Gladiator (2000) in which Máximo discovers that the infected wound on his shoulder has been treated with a handful of worms. Today, larvatherapy makes it possible to deal with antibiotic-resistant bacteria.
The philosophical fly
The painter Salvador Dalí was fascinated by flies. He lured them by smearing honey and date oil on the corners and whiskers. He considered them the main a source of inspiration for Greek philosophers, perhaps because he understood that in the small there is a radical form of truth: everything that lives, even what makes us uncomfortable, is temporary.
I think about this on the way back and I realize that we don’t get to talk about the philosophical fly. That forgetfulness seems unfair to me: his life is brief, but his presence is constant. Generation after generation, they survive our repugnance and our attempts at extermination with a patience that the Stoics would have admired.
Guatemalan Augusto Monterroso wrote that flies carry the souls of our dead. Thus, the metamorphosis of the fly has allowed it to go from egg to larva and from pupa to adult, but also from monster to detective and spiritual companion.
The next time we pray to the guardian angel, we might do so thinking of a creature with transparent wings and compound eyes that sees everything. We don’t know if our prayer will reach the right place, but it doesn’t hurt to try. Just in case.