Bugs. Just say the word, and people get squeamish. "To bug" is a metaphor for pestering, for irking. When someone "bugs out," he could be freaking out or getting the heck out of dodge. Maybe you've had a nasty "stomach bug." Flying, crawling, scuttling, scurrying, creeping, crawling, dangling, swinging, swimming bugs. Why would people want to spend their lives in close contact with these critters?
Well, as it turns out, bugs aren't as alien as you may think. Sure, they may have six legs (or more), but just like everything else on this blue marble we call home, bugs are inseparable members of our ecosystem.
Before we get into the nitty-gritty, let's get one thing as straight as a yellow jacket's stinger: Just what are we talking about when we mention the word bug? To answer that question, we need to talk about taxonomy, or the naming and classification of living things.
Basically, a "bug" is one of two distinct kind of animals, casually speaking: an arachnid or an insect. An arachnid is an animal with four pairs of legs and a body divided into two segments — think spiders, scorpions, mites or ticks. An insect, on the other hand, has three pairs of legs and a body divided into three segments (a head, a thorax and an abdomen). Maybe throw in a pair or two of wings and you've got a complete insect.
Both insects and arachnids belong to the arthropod phylum, which also includes a few other animals we might call bugs, such as centipedes, lobsters and crabs. For the purpose of this article, "bugs" refers loosely to all arthropods, but we'll mostly be talking about insects. So now that we know what we're studying, we need to get to the good stuff: Why?
Aside from the occasional spider or cockroach sighting inside your house, you probably don't think about bugs too much. Yet they play a vitally important role in our ecosystem — for better and for worse — and the better we understand them, the better off we'll be.
Some insects are helpful. For example, you may know that the bee population is on the decline, and that this has serious consequences for our food chain. Entomologists want to understand the cause and consequences of the decline because this free pollinating service has a direct connection to our agricultural economy — to the tune of $15 billion [source: Holdren]. Bees and other insects are responsible for pollinating many of the crops we depend on, like most nut and fruit species.
On the other hand, many bugs are responsible for the destruction of crops. An obvious example is the damage done by an insect feeding on a plant's fruit, roots or body. For instance, a cucumber beetle's appetite does not discriminate. Adult cucumber beetles eat the fruit, leaves, shoots and blossoms of their favored plant, while their larvae prefer to munch on a cucumber's roots. Insects like aphids can also introduce viruses, infections and diseases to crops, leading to widespread devastation.
And to make this relationship even more complicated, in the early 20th century we developed chemical pesticides to mitigate the devastation of the problem insects. But the real problem is self-imposed: In destroying harmful insects, we also destroy the beneficial ones — much like chemotherapy kills cancer cells but also wipes out healthy cells and tissues. If entomologists can learn how to effectively target harmful pests, the beneficial insects could have a chance at restoring a balanced ecosystem.
Insects are not just a problem in the field. They also invade stored foods, eating and/or nesting in a cozy silo of wheat or in that forgotten box of Bisquik in the back of your pantry. Of course, a bug's interest is not limited to the vegetarian. Some species of blowflies spend their first weeks of life in the flesh of their host, living off the surrounding meat. Fleas and ticks can cause anemia, while horn flies target cattle and can consume up to a pint of blood every day. Entomologists help us understand insects' life cycles and behaviors, which in turn helps us protect our own food supply and prevent foodborne illnesses.
Ups and Downs of Living with Bugs
Bugs may eat and maim our own grub, but we can strike back — by eating them. Maybe you've seen Travel Channel host Andrew Zimmern jet to Taipei or Ecuador and snack on some cocoons and worms, cooked or raw and wriggling. To the squeamish Western viewer, it's downright disgusting to watch. But economically (and historically), it just makes sense: Bugs are easily the most abundant and nutritious source of protein available, yet almost all of Western civilization has yet to catch on. Bugs are not the answer to global food shortages, but they are an effective supplement.
While our relationship with bugs and our food has always been obvious to us, our relationship with bugs and diseases has not. Malaria has afflicted humans for many hundreds if not thousands of years, but it was not until 1880 that a French army surgeon named Charles Louis Alphonse Laveran discovered parasites in the blood of a malaria patient. Seventeen years later, in 1897, a British officer by the name of Ronald Ross successfully demonstrated that mosquitoes transmitted the malaria parasite. With concrete evidence that insects can carry disease, a fascination with bugs was no longer a hobby; it was a necessary science integral to our survival.
Or how about a sexier example? Have you heard of the kissing bug, aka the assassin bug? While there are dozens of species of the so-called kissing bug, those native to Central and South America can carry Chagas disease, responsible for the deaths of 50,000 people each year and the infection of some 18 million people altogether [sources: CDC, University of Wisconsin-Madison]. The transmission of Chagas disease really is the "kiss" of death: A deadly parasite lives in the kissing bug's digestive system and is then excreted by the bug after feeding, often near the victim's mouth at night. The unwitting victim may sleepily wipe or scratch the bite, introducing the parasite into her bloodstream. If left undiagnosed, the parasite may cause mild, nonspecific symptoms like vomiting or diarrhea and eventually more severe complications like an enlarged heart or cardiac arrest. For the hellish, sci-fi story of the kissing bug and Chagas disease alone, bugs are certainly worth studying.
Bugs Are Cool
Let's get real here — bugs are just cool. Why wouldn't we want to study them?
Take the social structure of a termite colony for example. Termite colonies are organized in castes, and each caste has its own function. Any termite you encounter is a member of the reproductive, soldier or worker caste. And regardless of whether a termite is male or female, if it's a soldier or worker, it's sterile. Only a member of the reproductive caste can do just that: reproduce. If a particular caste is over-populated, the termites will resort to cannibalism to restore balance.
But studying something just because it's cool often does not attract research grants. The most important lessons we as humans can learn from the natural sciences is humility. The problems we encounter in everyday life may very well have a simple solution in the insect world.
Imagine trying to drill a hole in concrete: You're leaning into the drill, trying to leverage your force against the solid, unwelcoming mass. It's hard. So how does a horntail wasp, an insect as light as a feather, drill into trees with such little effort? To find out, entomologists took a closer look at that "horn tail." The tail is really two needles, inching into the wood by "pushing off and reinforcing each other like a zipper" [source: Goldenberg and Vance]. Turns out, this very design could theoretically help astronauts drill into the surface of Mars or even an asteroid — where leveraging your weight won't work because there's little to no gravity. When entomologists study the insect world, they may resolve a problem we didn't even know we had.
Despite some pretty scary bugs out there, an overwhelming majority of insects and spiders are beneficial to human beings — or at the very least, they're harmless. According to the Smithsonian Institute, "at any given time there are some 10 quintillion (10,000,000,000,000,000,000) individual insects alive." Recent estimates suggest there are more than 200 million insects for each person on the Earth. And while that statistic may immediately conjure up horror-movie images of maggots and swarms of mosquitoes, take comfort in this: Butterflies are bugs too, as are rolly pollies and those friendly little ladybugs.
Above all, take comfort in the fact that you are many times larger than the largest bugs on Earth. New Zealand's giant weta bug grows as long as 3 inches (7.62 centimeters) and weighs as much as 1.5 ounces (42.5 grams). While giant for a bug, that's still a lot smaller than your average shoe or rolled-up newspaper. And an entomologist will confirm that a weta bug cannot (and will not) carry your child off to Middle Earth, nor will it eat you alive. At least, probably not.
Author's Note: Why do we study bugs?
As a liberal arts undergrad at the University of Georgia, I was required to take two science courses: one in the "physical" discipline and another in the "biological" discipline. I eagerly took the geology course first semester my freshman year, but I really dreaded fulfilling that biological science requirement. I'm not sure what originally compelled me to take Intro to Entomology, but each class from the first day was endlessly fascinating. I remain a lifelong amateur "bug" enthusiast, unless one of them is crawling on me.
More Great Links
- Biodiversity Explorer. "Why do we study insects?" (April 10, 2015) http://www.biodiversityexplorer.org/insects/why.htm
- Centers for Disease Control and Prevention. "Parasites - American Trypanosomiasis (also known as Chagas Disease)." July 19, 2013. (May 6, 2015) http://www.cdc.gov/parasites/chagas/gen_info/detailed.html
- Centers for Disease Control and Prevention. "The History of Malaria, an Ancient Disease." Nov. 9, 2012. (May 21, 2015) http://www.cdc.gov/malaria/about/history
- Cornell University Department of Entomology. "Top 10 reasons to study bugs." (April 10, 2015) https://entomology.cals.cornell.edu/sites/entomology.cals.cornell.edu/files/shared/documents/top-10-reasons.pdf
- Encyclopedia Britannica. "Assassin Bug." Feb. 11, 2015. (May 4, 2015) http://www.britannica.com/EBchecked/topic/39144/assassin-bug
- Goldenberg, David and Eric Vance. "10 Technologies We Stole From the Animal Kingdom." mental_floss. Sept. 7, 2013. (May 21, 2015) http://mentalfloss.com/article/22702/10-technologies-we-stole-animal-kingdom
- Holdren, John P. "Announcing New Steps to Promote Pollinator Health." The White House, Office of Science and Technology. May 19, 2015. (May 22, 2015) https://www.whitehouse.gov/blog/2015/05/19/announcing-new-steps-promote-pollinator-health
- Krishna, Kumar. "Termite." Encyclopedia Britannica. June 5, 2014. (April 30, 2015) http://www.britannica.com/EBchecked/topic/588027/termite
- Purdue University Department of Entomology. "Importance of Entomology." 2014. (April 10, 2015) http://extension.entm.purdue.edu/radicalbugs/default.php?page=importance_of_insects
- Smithsonian Institution. "Numbers of Insects (Species and Individuals)." (May 5, 2015) http://www.si.edu/encyclopedia_si/nmnh/buginfo/bugnos.htm
- Texas A&M Agrilife Extension. "Insects/Pests." (May 5, 2015) http://livestockvetento.tamu.edu/insectspests/
- United States Department of Agriculture Forest Service. "Insect Basics." (April 19, 2015) http://www.fs.fed.us/wildflowers/pollinators/animals/insectbasics.shtml
- The University of Arizona Department of Neuroscience. "Basic Kissing Bug Facts." 2013. (May 4, 2015) http://neurosci.arizona.edu/kissingbugs/basicfacts
- University of California Davis. "UC Pest Management Guidelines: Cucurbits." June 2012. (May 22, 2015) http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/PESTS/cucumberbeet.html
- University of California Museum of Paleontology. "Introduction to the Arthropoda." 2006. (May 5, 2015) http://www.ucmp.berkeley.edu/arthropoda/arthropoda.html
- University of Wisconsin-Madison School of Veterinary Medicine. "Chagas Disease (Trypanosomiasis): Introduction." (May 6, 2015) http://www.vetmed.wisc.edu/pbs/zoonoses/Leishtryp/Chagindx.html
- Wigglesworth, Vincent Brian. "Insect." Encyclopedia Britannica. July 20, 2014. (April 30, 2015) http://www.britannica.com/EBchecked/topic/289001/insect
- Worldometers. "Population." (May 4, 2015) http://www.worldometers.info/world-population/