Invite Ants to Lunch
by Sue Smith-Heavenrich
Ants may be tiny-but they're serious eaters! Try these neat experiments to find out what ants in your backyard like to eat.
Ants love a picnic. And just like you, they have favorite foods. For example, harvester ants from the southwestern United States collect seeds. Carpenter ants like to eat insects and juicy fruits. Leafcutter ants munch on fungus salads that they grow in underground gardens.
Want to find out what the ants in your neighborhood like to eat? Place small amounts of different foots on the eds of an upside-down plate. You can use peanut butter, honey, mashed banana, grated apple or cheese, and seeds (such as barley, sunflower seeds without shells, or sesame seeds).
Put this feeding station where there are lots of ants. Wait three minutes and count the number of ants feeding on each food. Count how many there are every three minutes. (You can keep track of the info by writing it down in a notebook).
What happens if two different kinds of ants come to your picnic? Watch and find out! (Most likely you'll get just one kind though.)
Fussy Eaters?
Ants don't always take the first food they find. Instead, they may investigate, touching many pieces of food with their antennae. What does this bit taste like? Exactly how big is it? Those are the kinds of things ants are checking out. When they finally choose a food, the ants carry it back to their nest.
Do your ants prefer big seeds or smaller ones? Sweet crumbs or less sweet ones? Here's a test: Give ants a choice between full-strength honey and honey-water mixture (add one teaspoon of honey to five teaspoons of water). Offer a few drops of each choice side-by-side at a feeding station. Then every three minutes count the number of ants you see near each site.
How Far Will They Go?
Want to see how far ants travel when they go out to collect food?
First find and ant nest. You can do that by following some ants when they carry food home. Now you know how far the ants traveled to get to your food station. Next, move the food station about one foot (30 cm) farther from the next. Do the ants find it? If so, move the station again. Keep moving the station until the ants no longer show up.
Spreading the News
Once ants find a food they like, they work quickly to collect it. Usually they try to get their nestmates to help. How long does it take an ant to tell others that there's food nearby? To find out, offer their favorite food at a feeding station. After the first ant finds the food, begin counting the ants at the food source every minute. Also, watch their behavior. When the first ant heads home, what does it do when it gets near one of its nestmates? Does it feed the other ant a bit of food? Or do the two touch their antennae together? Is the ant with the food dragging its back end on the ground? It may be leaving a trail of smelly chemicals that leads to the food.
Can you think of other cool "ant-picnic" experiments to try? How about offering a second picnic in a different place? Do the ants there act differently? Whew - enough questions! Go outside and start asking some yourself!