Function
Soldier termites are so named because their sole purpose in life is to defend their colony from predators. Because soldier termites do not reproduce, they rely on the queen and king termites of their colony to perpetuate their species. This is not a thoughtful, altruistic decision on the part of the termite. Rather, it is a behavior governed by genetics and biology.
Significance
All termites look the same when they first hatch from the egg. As a termite matures, it assumes the form of its social position, or caste, within the colony. According to caste, the termite will eventually be a worker, soldier, queen or king. The physical and behavioral differences between castes are thought to be determined by a combination of genetics and environmental influences on the termite as it matures.
Features
As with other insects, the bodies of all termites are composed of an abdomen, thorax and head. Three legs are attached to each side of the thorax. The head is ovate and features antennae, eyes and mandibles at the mouth. Termites are white or light yellow and resemble ants somewhat; but whereas an ant's abdomen is differentiated from the thorax by a narrow "waist," termites are thick-waisted.
Identification
Soldier termites have large, dark heads with powerful mandibles for crushing predators that threaten the colony. In some species, soldiers are twice as large as worker termites, and may spray noxious chemicals from a snout on the front of their head. Soldier termites of species common to North America are roughly the same size as worker termite: about 7/16 to 3/8 inch. North American soldier termites do not emit toxins.
Considerations
For all its physical might within the termite colony, the soldier termite is relatively helpless. Because they don't reproduce, soldier termites have no need to fly away from the colony, so they don't have wings. Soldier termites sometimes have eyes, but in most species, they are blind. And though its mandibles are impressive to look at, the soldier termite is incapable of feeding itself, and is fed by worker termites. The soldier termite can bite, but it is not aggressive or poisonous.