By Richard Gambino
One day this summer, I was taking ultra-close photos of flowers in my front yard. Suddenly, an interesting insect landed on a dandelion at my feet, and seemed to all but invite me to take its picture. The creature had a dark, almost figure-eight body, with a sharp white line along each of its sides. Its transparent wings had intricate patterns of thin lines. Its eyes were big and dark, set on a bubble-like head that seemed almost transparent. I’d never seen such a critter, so I brought my photo of it to my friends at the SoFo Museum of Natural History in Bridgehampton. They identified it as “a fly mimicking a bee.” That is, the genes of some flies have adapted a kind of protective camouflage that make them look like bees, and thus gives them a survival advantage. Predators that normally feed on flies would not risk getting stung by attacking a bee.
I’m not too disappointed in myself for not being able to identify the bee-mimicking fly. You see, it isn’t just my knowledge of insects that’s very incomplete, but this in fact is true of all humanity. Yet what we know greatly challenges my imagination, and opens fantastic possibilities.
And your imagination and sense of fantasy? Let’s see. For each of 7 billion humans today, there are 200 million individual insects. If all the world’s insects were put on a gigantic scale, there would be 300 pounds of insect flesh for each pound of human flesh in all humanity. The 900,000 known species of insects comprise some 80 percent of all living species. Insects have been around for 400 million years; our species of Homo sapiens came to maturity only 200,000 years ago. Many new species of insects are discovered each year. And it’s estimated that as many as 30 million more insect species exist than have been identified.
In the U.S., there are “only” 91,000 known species of insects, and perhaps almost as many unidentified species. More, I can’t wrap my mind around the potentials for explosive growth in the numbers of insects. Consider deer ticks, which carry Lyme disease. A female tick hangs on a plant until a warm-blooded creature, e.g., a mouse, deer, rabbit, human, chipmunk or bird, brushes by. It attaches itself to the animal using backward-turned “teeth,” drinks its blood, then falls to the ground and lays literally thousands of eggs. These hatch in about a month, turning first into blood-sucking larvae, then into blood-sucking adults, and the new female adults start the cycle all over again, each of them in turn producing thousands of eggs. Fortunately, most insects, including ticks, don’t survive long enough to reproduce. How many deer ticks do we have this year? Well, “Mathematics are well and good,” as Albert Einstein reportedly said, “but nature keeps dragging us around by the nose.” Ditto for how many bee-mimicking flies.
With short reproduction times, countless species of insects evolve rapidly, some to become more impervious to predators, and some more impervious to insecticides. What may we be facing in the insects we encounter next spring and summer? Consider a report by entomologists at the University of Illinois that says that already some insects, e.g., individual honeybees, “actually differ in their desire or willingness to perform particular tasks,” and draws the conclusion: “Insects have personalities too.”
One last point. My insect friends tell me they would like us humans to keep in mind our place in the world as a relatively recent, relatively sparse and relatively slow-evolving species.
But not to worry. In a few months it’ll be winter, so we’ll get some reprieve from evolution going buggy. At least for a while.
RICHARD GAMBINO learned a long time ago that nature — both in its realities and its possibilities — is far more fantastic than science fiction.