Would You Squash This Bug?

Many people would say there’s nothing wrong with killing that fly—or any bug for that matter. Scientists estimate that there are about 10 quintillion insects wriggling, fluttering, and skittering around our planet. (That’s 10 followed by 18 zeros!) Does one person squishing one insect really matter?

Besides, squashing bugs can be a way to protect ourselves. About a quarter of Americans are afraid of insects like flies and cockroaches and arachnids like spiders and scorpions, according to research from Chapman University in California. Scientists say one reason humans have a fear of bugs is for protection: Some bugs can make us ill.

Take that fly trying to snack on your Popsicle. Annoying? Sure. But it can also be dangerous. Houseflies lay eggs on and eat rotting garbage, animal feces, and roadkill, and they can pick up harmful germs as they go. When a fly lands on our food, it can pass those germs on to us.

“Flies in our kitchen can spread diseases, so I would argue it is OK to kill houseflies,” says Matan Shelomi, an entomologist (a scientist who studies insects) in Taiwan. The same, Shelomi says, goes for mosquitoes that suck our blood, which can also spread diseases.

Then there are bugs that can cause serious damage to the environment. Take the spotted lantern fly. These insects are native to Asia. But they were accidentally brought to the U.S. about a decade ago. Since then, they have been spreading from state to state, devouring everything from walnut trees to rosebushes—and causing many millions of dollars in damage. That’s why government leaders have urged Americans to stomp on any lantern fly they see.

Of course, not all bugs cause harm. Less than 1 percent of insect species pose a threat to people or the environment, according to the U.S. Department of Agriculture.

In fact, insects play an essential role in the web of life, explains entomologist Michelle Trautwein of the California Academy of Sciences. Without honeybees and other pollinators, for example, about 150 kinds of fruits and vegetables—from watermelon to squash—wouldn’t be able to grow. Cockroaches play a key role in turning food scraps, dead leaves, and other waste into rich soil. And flies? They’re a major food source for birds, reptiles, and other creatures.

So maybe we shouldn’t be so eager to squash every bug that buzzes our way—especially because insect populations have been declining in recent years. Indeed, a 2020 report published in the journal Science revealed that the global insect population is dropping by about 9 percent each decade.

On the other hand, scientists say the decline is likely due to factors like climate change and the pesticides and fertilizers used in large-scale farming. Killing a gnat hovering around your fizzy drink isn’t really the problem.

Still, some people believe it’s wrong to harm any living thing, no matter how small the impact of killing it might be. All insects and arachnids are living creatures, like us, Trautwein points out. “If you see a beetle or bee stuck in the water, you can see it’s struggling to survive. It’s trying to live, just like every other living thing is,” she says. “It’s important to have a respect for life.”

There are certainly plenty of ways to get rid of bugs that don’t involve killing them. For mosquitoes, you can use bug spray. You can sweep up crumbs to make your kitchen less appealing to ants. And if you find, say, a stink bug in your bedroom, you can put a glass on top of it, slide a piece of paper underneath, then release it outside.

So what about that fly buzzing around your Popsicle? It is potentially disease-spreading, and squashing it isn’t likely to harm the environment. So if it’s really bothering you, you might go ahead and squash it—if you can catch it!

Then again, you might simply shoo it away so it can live to buzz another day.