You and Your Students!
Vicki Cobb, Education World Science Editor
Do a taste test with ants: sugar vs. aspartame.
Chemistry, Nutrition, Biology
Setting the Scene (Background)
One of my earlier experiments, Sweetness and Lite, demonstrated the difference in density between regular and diet soda. Manufacturers of diet soft drinks depend on fooling people. They are counting on the fact that drinks containing artificial sweeteners taste pretty much the same as those flavored with sugar.
Are ants as easily fooled as people are? That's what this experiment is all about!
As soon as spring comes, ants get active. It shouldn't be hard to find an anthill in your schoolyard or a nearby park. That's all you need to do this experiment.
Use two cans of the same kind of soda -- one "regular" (with sugar) and the other diet (with aspartame or NutraSweet). Find an anthill. That shouldn't be too hard -- ants are almost everywhere. Put a few drops of the regular soda on one saucer; put a few drops of the diet soda on the other saucer. Place the saucers near the anthill. (You can also put the drops on another hard surface -- such as a concrete walkway, a rock, or a patio stone -- near the anthill. There should be at least six inches between soda samples.)
Now wait It won't be long before the first ant scouts discover your sweet temptations.
Ants definitely prefer the "real thing" (the "regular" soda with sugar). Within a few minutes the word on the hill is that the sugared drink is the one to visit. Talk about effective advertising!
This experiment also demonstrates communication in a group of social insects. Ants somehow communicate their discoveries to each other. Your students might want to learn more about ants to find out how they communicate.
Behind the Scenes
The molecules of natural sugars fit into an ant's taste receptors, which are located on its antennae and in its mouth. Ants don't have receptors that "fit" aspartame molecules, so the artificial sweetener doesn't taste sweet to them. Since ants are not trying to lose weight (they do have waistlines, after all), they correctly pass up the diet drink in favor on the one that will nourish them.
Ants are not foolproof! They can be tricked by drinks sweetened with saccharine. Put some saccharine in water to test this idea.
Article By Vicki Cobb
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