Identifying
Features
Appearance (Morphology)
- The body of an ant is clearly divided into three sections: the head,
the thorax, and the gaster. (The narrow waist is actually within the abdomen, so the part of the abdomen behind the waist
is called the gaster.) The waist can be made up of one or two small segments, depending on the species.
- Ants are social
insects living in colonies comprised of one or a few queens, and many workers. The queen generally stays deep and safe within
a nest. Most ants that you see are workers and these are all females. Depending on species, workers may be similar in size,
or come in a range of sizes.
- Ants tend to come in dark or earth tones. Different species are black, earth-tone reds,
pale tans, and basic browns.
- Caveat: Ants are very diverse and it is difficult to generalize about them. Therefore,
if ants you collect don't quite fit these generalizations, consult such books as The Ants (Hölldobler
and Wilson) and/or local experts.
Adult Males and Females
When ant colonies reproduce, the new
queens and males may be found in the colony. These are "flying ants" and
have two pairs of wings. Males generally have small heads, large eyes, large thoraces, and a pair of claspers at the end of
the gaster. Once they fly (and mate), males do not live very long. After mating, new queens break off their wings and never
fly again. Without wings, they can generally be distinguished from workers by their larger body size, larger thorax and larger
abdomen. All workers are females.
Immatures (different stages)
Ant larvae are white and grub like.
They have no legs and don't move about much on their own. You can generally see a large, dark stomach through their cuticle.
Ant pupae look like white adult ants, with their legs and antennae pressed close to their bodies.In some species, larvae spin
silk and the pupal stage is inside a cocoon. Newly emerged adult ants are often paler than older ones. It may take them several
days to reach their final color.
Natural History
Food
Most ants that are
easy to keep in the classroom are generalists, eating a variety of small insects that they capture, dead insects they happen
to find, nectar, or honey dew. They need a balance of carbohydrates and protein. Protein is especially needed for the queen
to make eggs and for the larvae to grow.
Habitat
Most ant species live in the soil. Some, like
the carpenter ants, also live in wood (they excavate, but do not actually eat the wood). Some ants live in cavities made inside
plants, such as acorns, twigs, and galls.
Predators
A variety of reptiles or amphibians (particularly
toads and lizards), spiders, other insects such as assassin bugs, and other ants may prey on workers. Bats, birds, and occasionally,
people capture and kill or eat the flying males and females.
Interesting Behaviors
Since ants
are social they display many behaviors that remind us of our families and society. For example, worker ants take care of larvae
by feeding and washing them. Ants are able to communicate with each other. They are able to communicate, among other things,
directions (to where the food is) and alarm.
Impact on the Ecosystem
Positive
World wide, ants are one of the most important predators on small invertebrates, including other insects. Leafcutting ants
in the American tropics are the most important herbivores (plant consumers), outranking grazing mammals. In many ecosystems,
ants are important dispersers of the seeds that they harvest. In desert regions, they are one of the principle consumers of
seeds. Wherever ants live, they turn over and aerate the soil as much or more than earthworms (depending on the specific ecosystem).
(For more information, see Hölldobler and Wilson's book).
Negative
A few ant species are
considered pests, because they live in and protect territory that we consider ours or because they want to consume resources
that we need. For example, leafcutting ants (see "Positive" section above) compete with us for crop plants in the
American tropics. Fire ants colonize damp grasslands (including lawns!) with alarming ease. Carpenter ants, adapted for living
in dead wood, consider the dead wood (lumber) in houses fair game, especially if it is damp. A number of opportunistic ant
species can overrun kitchens, pantries, and pet food areas in search of suitable food items. Also, some ants (like their relatives
the wasps and bees) have a potent sting. As with bees, some people can become hypersensitive to ant stings.
Collecting
Live Insects
Where to find
Ants are found under logs, particularly rotting logs that
pull apart easily. In some parts of the U.S., ants live in acorns or twigs on the ground. Catch new queens near porch lights
in warm months. If you are lucky, you may see new queens before they have found a place to dig. Worker ants and vertical dirt
ant farms can be purchased from: Carolina Biological Supply Company, WardÍs Biology, Connecticut Valley Biological
Supply Co., Inc., Nasco Science, Science Kit and Boreal Laboratories. Some states (AZ, HI and TN) have restrictions to importing
different species of ants and require you to apply for a USDA permit.
How to collect
By gently
turning over rocks on warm spring days you may find a colony with the queen and brood. Since the light and air will disturb
the ants, work quickly to gather the queen and as much brood as possible before they go underground. Use an aspirator or small
shovel to remove the ants and brood from the colony. If you use a shovel to dig, take care when placing the dirt and ants
into a container with light oil or Vaseline around the rim so that the ants can't escape. Let the dirt dry out slowly. Place
the test tubes with water and cotton plugs in the box on top of the soil. As the soil dries out, the ants will move into the
tubes. When most of the ants are in the tubes, transfer them to a dirtless nest. (Place an incandescent light over the container
to make the ants move faster).