JANUARY
2004

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

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Check out these books by Tom Turpin:

Flies in the face of fashion

What's Buggin You Now?

 

 

 

01-08-04

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Insects Bite and Sting for Good Reasons


Most people understand that some insects bite and some insects sting --just two of the reasons that many folks don't like insects. In fact, biting and stinging might be the main reasons that humans hate insects in general.

Insects haven't taken to biting and stinging humans just to be mean. Biting and stinging behavior is associated with survival of these six-legged creatures. Such activity is generally related to food for the insect or its offspring. Take, for instance, the bite of a mosquito. It has to do with getting a blood meal. The same is true for horse flies, deer flies and stable flies when they bite.

Stinging can be related to procuring a meal for the offspring. Many wasps use a stinger to paralyze an insect as food for their babies. That is why a cicada killer wasp stings a cicada and drags it to a hole in the ground for the offspring.

In other instances, the sting functions to defend the insect or its colony from harm. Wasps will sting for that reason although they also use their stingers to procure food. Bees, on the other hand, only use their stingers as defensive weapons.

Insect stings cause pain and suffering to recipient animals. And that is the way the insect wants it to be. The sting is designed to get the animal to let go of the insect or run away from the nest.

So which insect has the worst sting? It probably depends on whom you ask. There really hasn't been much research on the subject. But, a few years ago, Christopher Starr wrote an article entitled, "A Pain Scale for Bee, Wasp and Ant Stings." In the article, Starr concludes that the severity of stinging is related to "the number of potential defenders of the colony, their readiness to attack, and the effectiveness of a single sting."

The first two stinging severity categories, numbers and willingness to attack, are easy to understand. Especially by any of us who at some time in our misspent youth intentionally disturbed a bumble bee or hornet nest in order to incite a human and insect war. This, I have been told, is primarily an activity of young boys! Rest assured, though, that the human participants quickly learn that insect numbers and willingness to attack have a direct relationship to pain from insect stings.

The third category, the one dealing with the effectiveness of a single sting, is difficult to define. The reason is that the severity of an insect sting is related to the type of poison, the amount of poison, the structure of the stinger and the reaction of the animal to the sting. For instance, some people are allergic to the poison used by insects in stings. In this case, the person will show such a severe reaction to the poison that they could die without medical treatment.

For most people, though, the response to an insect sting is local pain and swelling. As a true scientist, Starr ranked insect stings on a pain scale of 1 to 4 where 1 is slight pain and 4 traumatically painful. On this scale, the sting of a honey bee, bumble bee or yellow jacket is rated a 2. A paper wasp, like those that build nests under the eves, was given a 3 -- sharply and seriously painful. South American bullet ants were ranked 4.

However, we know that the pain of a sting varies among people. Sometimes, in individuals, the pain gets less as you get stung more often. Bee keepers can become tolerant to honey bee stings during the summer season. On the other hand, some people become more susceptible as they get more stings and, at some point, might exhibit such a severe reaction that medical treatment becomes necessary.

Insect bites also vary from person to person in the amount of pain they inflict. For instance, when a mosquito bites, there may be little or no pain experienced by the victim. That is the way the insect wants it to be since it would like to take a blood meal without the donor noticing. However, the chemical it injects to keep the blood from clotting causes the irritation we know as mosquito bites and the amount of irritation varies from person to person.

So the severity of insect bites and stings depends on the insect and on the reaction of the person. But rest assured that insects have a reason for bites and stings -- and it's not just to make us suffer!

 

 

Writer: Tom Turpin
Editor: Olivia Maddox