A Little Bit More
I think it goes without saying that the idea of having maggots crawling about on one's body is repulsive to almost anyone. However, if maggots can provide medical assistance that you can’t find elsewhere, most of us would be much more favorable to these creepy-crawlies. Antibiotics, once heralded as the cure for mankind have not proven as dependable in recent decades and the medical community is going back to some older techniques for healing.
The medical profession has known for hundreds of years about the benefits of using maggots to help heal infected wounds. Doctors used maggots during the Civil War and reported that wounds healed more quickly and with fewer complications using this technique. The technique is called maggot debridement (deh-BRIDE-ment) and involves the removal of dead tissue from a patient’s wounds.
Only a few species of flies are used for this procedure since some fly maggots do more damage, than help, to patients. But the Green Bottle Fly maggots, along with a few other species, feed only on dead tissue and do not harm the living cells surrounding a wound . Five to ten maggots are placed on each centimeter of wound and then covered to keep them in place. As the maggots squirm about on dead tissue, they produce strong chemicals that help them break down dead tissue into a semi-liquid, which is then absorbed and digested.
In nature, there are many different kinds of blow flies, many with green or blue metallic coloration. Most blow flies are scavengers that locate and then lay their eggs on dead animals, providing their young with plenty of food. Not a very pretty picture, maybe, but the cleanup squad’s decomposing lifestyle is an invaluable part of the environment.
Activities
Make it Shiny
Objectives: Hone artistic skills
Materials: Some kind of coloring material (colored pencils, paint, chalk), color reference picture of Blow Fly
The flies discussed in this unit are especially colorful and their iridescence, if you can overlook their immature form, is particularly beautiful. Coloring in something that looks iridescent (or at least very shiny) is not easy but this activity will hone your students’ observational and technical skills. There are both Green and Blue Blow Flies so your students can choose which of these two colors they want to use. (Don’t use the color illustration in the unit for help – I’m restricted on the amount of color I can use online so the iridescence of the fly isn’t very convincing)
Although a Blow Fly’s body is basically blue or green, its hard body covering reflects a variety of colors when in strong sunlight. Make a copy of this ink-line illustration for each member of your class and have students see if they can create an iridescent look on their fly.
(HINT: You’ll find that going from a very dark color to a very light color within a small area will help convey the iridescent look more convincingly. Good Luck!)
Iridescence - (a play of colors producing a rainbow effect as in soap bubbles)
Key Concepts
Behavior and Regulation, Growth and Development, Identification
Questions
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Posted by Nathan Houser on August 28, 2005 at 02:49 PM
Q: I have a compost container where I compost fruit and vegitable scraps. For several years there has been a large family of red worms living in and no doubt under the composter (it sits on the ground). A few days ago I noticed great masses of larvae of some kind (either maggots or grubs I suppose—they are about half an inch long, possibly just a bit longer) swarming in the composter. I have no Idea what is going to hatch and wonder if I should try to eradicate them (but I'd hate to kill the worms). Any thoughts on this? Thanks.
A: I'd leave the larvae (maggots?)alone. For one thing, they're helping to breakdown the foods you've placed there so they're really "helping" you. My guess is that you placed some food product in your compost that simply coincided with an insect's time to lay its eggs. This might explain why you haven't seen them before. Of course, insect populations do wax and wane so this may simply be a good year for this particular insect.
I do have an idea that you might want to try. Keep an eye on the larvae and when they advance into their pupal stage, put a few into a container(jar with a screen on top works well). Then when they emerge, you'll get to see exactly what they are. Incidently, if they're grubs (beetle larvae) you should be able to see a definite head and tiny legs. If they're maggots (fly larvae), they have no legs nor an obvious head.
Hope you're able to ID the larvae so you'll know if it ever happens again. Thanks for a good question.
Posted by Travis Isreal on August 09, 2005 at 09:31 PM
Q: Why can the Blow Fly maggot survive eating dead tissue only,but most other maggots Can't.
A: Each species (kind) of fly has its own way of surviving. Some eat only plants, some eat only animal material, some eat both, and some eat dead things. We don't like the idea of eating dead animals but if you think about it for awhile, it does make sense. Dead meat is often easy to find (there are animals dying all the time) and as it rots, the meat is easy to digest for maggots - it's really a good food source even though it seems yucky to us.
Posted by Hannah Bailey on March 09, 2005 at 11:21 AM
Q: What is an amphibian? I found this word in the frog article. Thanks
A: Amphibians are animals like frogs, toads, and salamanders. These are animals that live part of their lives in water and part of their lives out of water. Have you ever heard of an amphibious vehicle in the army? These are vehicles that can go on land or go in water and these were named after amphibians. Hope that helps you remember.