Artwork by Michael DiMilo
By Geoff Carter
We humans are the greatest of Earth’s parasites.
–Martin H. Fischer
Anyone who’s studied high school biology—or spent a summer evening outdoors in Wisconsin—is familiar with the concept of parasitism, an association between two organisms in which one benefits, or survives, at the expense of another. Mosquitoes, ticks, fleas, and leeches that live by sucking the blood of other creatures are examples of this. Cowbirds are a common type of brood parasites that lay their eggs in the nests of other birds, sometimes destroying the eggs of the original inhabitants who end up feeding and raising the cowbird fledglings as their own. Social parasitism is yet another example in which an ant species depends upon another to do its work—a type of slavery. Besides leeches and mosquitoes, humans are also victimized by fungi, viruses, protozoa, and tapeworms. Parasitism is a part of the natural cycle; so are mutualism and commensalism.
Creatures in the natural world live in whichever niche the evolutionary process has placed them. Some are herbivores or carnivores or omnivores. Plants produce their own food. Some are parasites. Other creatures scavenge, but whatever they do to survive, each creature only takes what it needs—except man, the ultimate parasite.
Human civilization as we know it began only about six thousand years ago. Before then, people lived hand to mouth, hunting and gathering (living paycheck to paycheck as it were). The advent of agriculture and cities enabled people to specialize and begin to build and create at the expense of the natural world. They cut down forests, built great cities, mined gold, silver, and other precious metals, and started accruing knowledge, all noble pursuits. But instead of replacing the resources they took from the world, mankind simply shrugged and, in their unfettered arrogance, took even more.
Today, agricultural corporations and farmers have used—and still use—pesticides that have decimated the world bee population to the point where the process of pollination is at risk. And if flowers are not pollinated, fruit and vegetables cannot grow, and people will starve. Insecticides, fungicides, and other soil additives are deadly to fish, earthworms, butterflies, and other links in the food chain. Because of the wholesale extermination of mosquitoes, bird, and bat populations, who depend on those pesky bugs for their diets, are plummeting and throwing the entire food web into chaos. And these deadly chemicals are used to increase crop yield—read profits. This human benefit—money—is reaped at the expense of other living creatures, and very possibly, our own survival. Human parasitism.
Herbicides are another example of a sort of abstract parasitism. We don’t need to kill weeds to survive, but we don’t hesitate to do so in order to make our lawns neat and orderly. This is an even more pernicious type of parasitism, sacrificing organisms (yes, even weeds are alive) to make our lawns neater and greener—and to impress our neighbors.
Humans have never hesitated to overfish, to overwork the soil, to pollute our rivers and streams, and to pump enough greenhouse gases into our atmosphere to eventually destroy our climate as we know it. Rampant development in Arizona, Nevada, and southern California has nearly dried up the Colorado River.
In the past, hunters decimated the vast buffalo herds of the Great Plains in order to deprive Native Americans of their food supply. They harvested the hides and left the carcasses to rot in the sun. Mankind also has a sordid history of enslaving our fellow humans. In almost every aspect of our existences, be it social, economic, political, or environmental, we are the very definition of parasites. We are the Ur-Parasite.
But there is hope. Activists are clamoring for restrictions on greenhouse gases and other measures to safeguard our environment. “No Mow May”, a movement urging homeowners to not cut their lawns during the month of May to ensure the bee population a food source is burgeoning—much to the chagrin of the lawn maintenance industry. Organic farming has been making some inroads in the agricultural industry as well as with small farms and home gardeners. To help the embattled bird populations, more and more people are putting up feeders. The Monarch butterfly population, whose Mexican home habitat is being threatened by overdevelopment and whose main food source—milkweed—is being eradicated, has been supported by thousands of American citizens planting milkweed for them.
Citizens across the world are attempting to repair the damage done by parasitic humans to their own planet because of their unbridled greed. This begs the question of where these parasitic tendencies arise. Is the human race, like mosquitoes or leeches, biologically engineered to take advantage of lesser creatures for their own benefit? Of course, predation is a natural instinct; some species will pray on others to survive, as do parasites. But human parasitism has reached new heights. Is it part of our biological makeup to take advantage of the Earth’s forests, creatures, oceans, and atmosphere to a point where their very existence is imperiled?
Can we evolve? It seems as if we may be moving toward forms of mutualism (interactions between two organisms that benefit both) and commensalism (an interaction between two organisms in which one benefits and the other is neither harmed nor helped). Organic farmers who use ladybugs and praying mantises to control pest populations are providing those insects a steady food supply as they clean the garden, an example of mutualism. Treehouses do not harm the tree but provide shelter to humans, an example of commensalism.
The health and survival of non-human inhabitants of Earth are necessary to our own survival. This is basic biology. We’ve known about the dangers of greenhouses and climate change since the nineteen sixties. Yet there are segments of our society that continue to ravage the planet, to succumb to the worst of our parasitic instincts.
As Henry David Thoreau stated in Walden, “Wildness is the preservation of the World.” The natural world can be our refuge, our classroom, and our salvation. Today I was a brood of robins nesting on our front porch. The patience, stalwartness, and dedication of the mother to her young brood, who leave the nest after only two or three weeks should be an education for us all. This mother robin is demonstrating the most basic survival instinct in the animal kingdom, one that the human race, in its manufactured distractions and obfuscations, has sometimes lost sight of—family is all. Sacrifice and caring are all that matters. We too often forget that.
Surviving in the wild is extremely difficult. Some songbird broods have only a twenty-five percent survival rate. Yet they persevere without complaint or resentment. They do not envy, they do not covet, they do not unnecessarily hurt each other.
We, the parasites, have the power to overcome our natural inclinations. We have the means and the knowledge to do better. All we need is the will.