Issue Date: August 3, 2003

Six Bugs You'll Learn to Love

We worked with the Smithsonian to discover decent insects that get a bad rap. These bugs help humans in more ways than you can imagine.

By David Marino-Nachison

They may be bugs, but Jiminy Cricket and Flik -- the pint-sized stars of "Pinocchio" and "A Bug's Life", respectively -- are cute and lovable. And a few real insects are enjoying their day in the sun: Investigators on TV's "CSI" routinely use bugs to help determine time of death; museums use carpet beetles to clean off old bones.

For the most part, however, insects have a serious image problem. That's not surprising: With an estimated 10 quintillion (that's 10 followed by 18 zeros) insects on the planet at any given time, chances are the bad ones will hog most of the publicity. That's especially true during summer, when mosquitoes, bees, ants, gnats and other bugs ruin lots of picnics. But now some scientists have discovered -- or are working to discover -- ways insects can be harnessed to help humanity.

Our investigation of insects for human use has been slow in comparison with our widespread use of plants, which probably have been used for as long as humans have existed, says Gary Hevel of the Smithsonian Institution's National Museum of Natural History. That's partly because plants were readily available to early humans. Fortunately, we now have a far greater understanding of insects. For example, it's estimated that every insect carries 100 different chemicals, each of which could conceivably warrant study. And with some 900,000 known species of insects worldwide, Hevel says, "we're talking big numbers."

And big opportunity. To help give insects some better PR, USA WEEKEND Magazine collaborated with the Smithsonian to put together a list of insects (besides the occasional conscientious cricket or friendly ant) that hold great promise for the world of science -- and for you.

Mosquitoes

The tropical disease malaria is still a major problem worldwide. Extremely deadly if not properly treated, it kills nearly 3 million people each year, mostly in Africa.

Malaria is transferred only by mosquitoes, perhaps the world's least popular insect. When they bite an infected person, parasites infect the mosquito, and then it infects the next person it bites.

Currently there is no vaccine, and tactics to fight it range from insecticides to drug treatments to simple mosquito netting. But one day, mosquitoes may help combat the very disease they spread. Scientists are studying ways to genetically modify them so it's more difficult for the disease to grow in their digestive systems. The altered mosquitoes could be released into the wild to mate and produce offspring less effective at carrying malaria.

Honeybees

Land mines are inexpensive weapons, according to the United Nations' Mine Action Service, but their cost to the world community is much higher. As many as 20,000 people a year are killed or injured by land mines, estimates the International Campaign to Ban Landmines. Mines can render roads, farms and other land useless. They sometimes remain active decades after a military conflict has ended. The United Nations estimates there are more than 100 million active mines, and new mines are buried more quickly than old ones are safely unearthed.

That's where honeybees come in. They don't have noses, but they do have a strong sense of smell. With the support of the Defense Department, which has funded a project to study potential uses for creatures such as lobsters and geckos, researchers have trained honeybees to associate the smell of TNT -- short for trinitrotoluene, the high explosive -- with food. Scientists then track the bees' flight; if they bring traces of TNT back to the hive, there's a good chance a land mine is nearby. The research is still in its early stages, but it could lead to honeybees being used to search for other compounds as well.

Phorid flies

There are approximately 3,000 species of phorid -- or humpbacked -- flies, which scavenge for decaying plant and animal matter. The tiny bugs generally are considered pests, but they're actually doing their part to get rid of an even more dangerous insect.

The Department of Agriculture says fire ants, accidentally imported from South America in 1918, infest more than 300 million acres in 14 Southern and Western states and Puerto Rico. They force farmers to use pesticides or risk attacks on livestock and wildlife as well as damage to farm and electrical equipment. They also sting humans, leaving behind clumps of painful red welts that can take two weeks to heal. South American fire ants have flourished in the United States without their natural predators, phorid flies.

These "ant-decapitating flies" now are being released in Florida and Texas, sending fire ants on the run. But that's nothing compared with what happens when the flies catch them.

"They hover over the ants," explains Brian V. Brown, associate curator of entomology at the Natural History Museum of Los Angeles County. "In a split second -- faster than you can watch -- they swoop down, briefly land on the ant, jab an egg into the ant's head and take off again." Their larvae use the ant head for food before springing forth from their dead host to find further victims. "The head," Brown says, "sometimes falls off before the rest of the body dies."

Jewel beetles

These beetles are a kind of heat-seeking missile: When they detect a forest fire, they flock to the scene, because the females of the species like to lay their eggs in burned tree bark. The beetles find their targets, say researchers at the University of Bonn in Germany, by using two tricks: sensing the smoke forest fires create, and sensing the heat they generate. Jewel beetles, which can detect chemicals found in smoke rising 50 miles away, have infrared sensors finely tuned to detect the heat given off by forest fires.

Scientists and the Defense Department are interested in these natural heat-seeking sensors. Modern infrared detection systems, used mostly by the military, require powerful cooling systems, which can make them expensive, complicated and difficult to produce. Jewel beetles, however, don't require such systems, so the military hopes it can learn from the efficient way in which the insects sense infrared radiation, eventually creating man-made infrared sensors that are smaller, lighter, simpler and easier to maintain.

Cathedral termites

There are more than 10 times more species of insects than plants worldwide, says Stephen Trowell, chief scientific officer of Entocosm, founded by the Australian government in 2002 to work with its library of more than 1,000 Down Under insects and other invertebrates. Humanity long has viewed the plant kingdom as a medical resource, from ancient herbal remedies to drugs discovered using modern techniques. "But insects," Trowell says, "have hardly been looked at in terms of their ability to provide us with medicine."

Entocosm's research already has turned up some promising leads, particularly from a type of insect better known for its appetite for destruction. The so-called cathedral termite (Nasutitermes triodiae) isn't the kind that lives in and devours the wood in your home. Instead, this type houses its colonies in enormous mounds that can be more than 23 feet high.

Their bodies carry compounds that have shown the ability to kill infectious bacteria. These chemicals are part of a defensive secretion carried by the "soldiers" of the colony; they squirt it out of nozzles on their heads. Entocosm hopes that one day this finding can help produce antibacterial drugs.

Stoneflies

Drinking water in the United States is among the safest in the world, boasts the Environmental Protection Agency. But we still have to monitor the quality of our water supply, especially given the diversity of the sources -- including lakes, rivers, reservoirs and wells -- from which Americans get their daily fix.

For example, a healthy stream, according to the Water Environment Foundation, is a vibrant community in which moss, bacteria and algae are food for the insects that are, in turn, food for fish. When pollution changes a stream's water quality, the organisms that depend on it for life can suffer -- or die off.

Collecting insects from a pond or stream, says the Smithsonian's Hevel, can show researchers how much pollution exists in the water and can be a useful indicator of the increase in pollution over time. Stoneflies, which are particularly sensitive to pollution, now are helping humans test water supplies. These long-antennaed, two-tailed bugs are a favorite food of coldwater fish such as trout, and the EPA considers the insects a leading indicator of a stream's oxygen supply. Researchers can track changes in the bug's populations; if they continue to dwindle (or disappear) over the course of several checks, they can clue us in to not only the presence of water pollution, but also to how quickly the quality of a given stream has degraded.

David Marino-Nachison isn't looking forward to the return of the cicadas on the East Coast next summer.

Photos Beetle: Nathan Schiff, U.S. Forest Service, SRS. Stoneflies: Joe McDonald, CORBIS.