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Termite Biology
Short Reading
A termite is a type of insect. Insects have three body parts — head, thorax, and abdomen — and six legs, all attached to the thorax. Termites also have antennae
attached to their head that look like they are made up of tiny beads. Termites are about the size of ants, and look a lot like ants, except that ants have skinny "waists"
and termites do not. Ants also have bent antennae and termite antennae are straight.
Termites are sometimes considered pests because they eat wood, and some don't care if the wood is in a forest or a house! They use their hard, chewing mouthparts to destroy wood,
twigs, roots, leaves, paper, cardboard, and cotton fabric. All of these things contain a substance called cellulose, which the termites digest with the help of microorganisms
living in their digestive track. If these protozoa, bacteria, and fungi were removed, the termite would die of starvation!
Since termites spend most of their lives underground or inside wood, they cannot see or hear. Instead, they detect vibrations through their legs. When a termite colony is
disturbed by a predator, soldier termites rattle their heads against the side of a tunnel to warn the rest of the colony.
Activity — Intruder Alert!
At the beginning of a school day, arrange with a neighboring classroom to play Intruder Alert! Identify one student or teacher in each class to be a predator, but keep
their identity secret from the other classroom. Sometime throughout the day, each class should plan to send their predator into the other classroom. Each classroom should not
know when the other classroom's predator is coming. While the predator is walking between classrooms, the predator's home class should warn the neighboring classroom that a predator
is approaching by stomping their feet in unison for 5-10 seconds.
While the students will probably hear the noise of the stomping feet, they should also feel the vibration through the floor. Audible sound is produced when an object vibrates at
high frequency, transporting energy via a wave, through a medium such as air. Human eardrums are designed to sense these high frequency vibrations and translate them into sound.
How are the legs of a termite similar to a human eardrum?
Termite Distribution & Habitat
Short Reading
Termites are found all over the world and are very abundant in the tropics. Of the 2200 species known to exist, 45 of them are found in the United States. Not all termite species
infest buildings. In fact, fewer than 5% of all termite species are known to feed on the wood of buildings.
Termites require a very unique habitat. They live in dark, cool, and moist passages within and/or connected to their favorite food — wood. They have very thin skin and easily dry
out if they are exposed to the outside environment, and therefore require a constant source of moisture. Once a termite colony is formed, it is sealed by members of the colony to
maintain constant temperature and humidity levels.
Activity — Wetter is Better.
Explore how different environments affect moisture loss using dampened sponges. First, label and weigh several dry sponges. Then saturate the sponges and wring them out so that
they are equally damp, but not dripping wet. Weigh and record the weight of each wet sponge. Place each wet sponges on a small plate or margarine container lid (anything
nonabsorbent will do) in a different environment. Place one in a sunny windowsill, one in a dark closet, and one inside a shoebox in a dark closet. Brainstorm other locations
to place sponges where factors such as temperature, air movement, and light will be different. After about four hours, retrieve the sponges and weigh them again.
Determine how much water was in each sponge at the beginning of the experiment by subtracting their dry weight from their wet weight. Now determine how much water is left in
each sponge by subtracting their ending weight from these figures. How much water did each sponge lose? Which one(s) lost the least? The most? Why? How is a sponge similar
to a termite's body?
Termite Life Cycle
Short Reading
Most insects are solitary creatures. They may hang out with others of their kind, but they are responsible for their own care. Termites, however, are social creatures.
They live in large colonies where each member has a role in ensuring the success of the colony and keeping each other alive. These roles are determined by the needs of the
colony and by the termite life cycle.
Termites begin life as eggs, produced by the king and queen of the colony. The eggs hatch to become nymphs, which are immature termites. Nymphs may develop into any of three
kinds of adult termites - soldiers, workers, or reproductives. Soldiers have extra large, helmet-like heads used to defend the colony. Workers are the most numerous members
of the colony and do most of the eating! Reproductives continue the life cycle by supplementing the king and queen's egg production. At certain times of the year, reproductives
develop wings, leave the colony in great swarms (during this stage they are actually called 'swarmers') and those that survive start new colonies. Most swarmers get eaten by
birds, bats, ants, spiders, frogs, toads, and lizards! If something happens to the original king and queen of the colony, a new pair will arise out of the reproductives.
Activity — Junkyard Termites.
Study the termite life cycle and have students use miscellaneous classroom and household recycleables to create three-dimensional models of the termite life cycle. Encourage
students to be creative and bring in objects from home that would normally be recycled or thrown away. Create teams and limit the time given for each team to construct their
termite life cycle. At the end of the time period, allow each team to present their models. In addition to demonstrating their understanding of the termite life cycle,
discuss each team's creativity in design, materials, and presentation.
Termite Social Structure
Short Reading
The unique social structure within a termite colony is called a caste system. Each group of termites — soldiers, workers, and reproductives — is a separate caste.
While soldiers use their enlarged, helmet-like heads and jaws to slash, puncture, and crush enemies of the colony, they are still wingless, blind, and soft-bodied. They are
unable to feed themselves and rely on worker termites for food. Worker termites are appropriately named, as they do most of the work of maintaining the colony. Workers care
for eggs and nymphs, construct tunnels, excavate chambers, repair damaged nest systems, obtain food and feed the young, soldiers, reproductives, and each other, groom and
assist nestmates during molting, and aid soldiers in defending the colony. They are sterile (cannot reproduce), wingless, and blind. Reproductives produce all the offspring
in a colony, but rely on workers for food.
Whether a nymph forms into a solder, worker, or reproductive is determined by the needs of the colony at any given moment. These needs are communicated to members of the
colony through the sharing and distribution of chemicals called pheromones among members of the colony. This is called trophallaxis. Through the practice of constantly
grooming one another, colony members exchange nutrients and pheromones, and are actually communicating!
Activity — Sweet Nothings.
Discuss with students the idea of non-verbal languages. What non-verbal language is widely-used among the hearing-impaired? (American Sign Language.) American Sign Language
uses the sense of site for communication, in the absence of sound. What other sense(s) could be used to communicate? Discuss trophallaxis. What human sense is most like the
sense being used by termites during trophallaxis? (Taste.) In groups, have students create a non-verbal termite language by assigning meaning to different candy types.
Challenge each group to write and act out a skit (A Day in the Life of a Termite Colony) using their language by passing candy to one another to communicate. Have other
members of the class try to guess what term or action each candy represented in each group.
Role of Termites in Nature/Food Chain
Short Reading
In nature, termites represent important members of the food chain known as decomposers. Decomposers reduce and recycle dead plant and animal matter and return the nutrients
from this matter back into the soil. Termites focus primarily on fallen and decaying wood. Without decomposers refreshing the soil, new plants and trees would not take root
and grow to provide food for other animals. The food chain would be broken.
Activity — Pest Quest.
Visit a local natural area and search for fallen wood, decaying stumps, or rotten logs. Carefully tear into the wood in search of decomposers. In addition to termites, many
types of invertebrates are decomposers. You may also find fungi and slime molds. How many different creatures can you find? Encourage the students to sketch their subject
and findings in a nature journal, carefully noting the date, time, and location of the rotten log or stump. After a few weeks or months, visit the spot again to check on the
progress made by the decomposers. Again, have students sketch the stump or log, noting the date, time, and location. What has changed? How does it look different? What will
eventually happen to the stump or log?
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