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A termite (also known as a white ant) is any member of the order Isoptera,
a group of social insects that eat wood and other cellulose-rich vegetable matter. Most termite species
are tropical or subtropical,
but a few live in temperate regions. They are of great biological and economic
interest.
Formosan subterranean termites
Termites have biting mouthparts and are soft bodied, of moderate to small size. They live in dark nests and tunnels, except when
the winged alates emerge to leave their parent
colony. The bodies of flying individuals are dark, but termites which remain in the nest are whitish with only their heads being
heavily pigmented. The temporary wings of termites are long and slender, in two pairs that are similar to each other. The veins
near the anterior margin of the wing are strong and the rest are faintly marked. The wings are shed after the swarming termites
find a new nest site.
Termites do not physically resemble ants, their "white ant" name probably being due to
their similar social habits. The termite colony contains workers, soldiers, and reproductive individuals of both sexes. The
workers are developed in subordinate castes in several species. The soldiers have large
heads and strong jaws, and in some species are highly specialized. Many have jaws so overdeveloped that they cannot feed
themselves without the assistance of workers, and varieties are known that squirt noxious turpentine-like liquid through a horn-like nozzle. In some colonies, the queen becomes enormous and quite
helpless through the expansion of her abdomen as eggs develop. The workers feed and groom her and carry away her eggs to nursery
chambers. Termites undergo incomplete metamorphosis, with their freshly-hatched young taking the form of small termites that grow without
significant morphological changes.
Termites cannot themselves digest the wood that they consume. Instead they rely upon symbiotic protozoans in their intestines to digest cellulose for
them, absorbing the products of the protozoan symbionts for their own use. This relationship is one of the finest examples of
symbiosis among animals.
Because of their wood-eating habits, termites sometimes do great damage to buildings. Their habit of building tunnels wherever
they go and of remaining concealed within the wood where they work often results in their presence being unknown until the
timbers, riddled with tunnels until spongelike inside, give way. Once they have entered a building they do not limit themselves
just to wood, also damaging paper, cloth,
carpets, and other materials. In regions where termites are plentiful, no timber in
construction should be left in contact with the ground. Exposed timber can be made resistant to attack by impregnation with
creosote or other chemicals, but the most effective defence is a masonry foundation. Even so, termites are able to build tunnels with walls of packed earth
over several feet of masonry or work through small cracks to reach wooden parts of a building. When termites have already
penetrated a building, removing their means of access and destroying the colony with fumigation are usually effective means of
stopping further damage.
In some regions, notably arid tropical savannas, termites construct extremely
large and elaborate mounds to house their colonies. These termite mounds can have very distinctive forms, such as the compass
termite which build tall wedge-shaped mounds with the long axis oriented north-south for maximum solar heating, and are as hard
as concrete. Some mounds can reach heights of 20 feet (6 m) or more. The internal
structure of these mounds can be quite complex, with ventilation chimneys for active temperature control, nursery and
waste-disposal chambers, and a well-defended internal fortification containing the queen.
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Sometimes misspelled for Thermite, an aluminium mixure with another metal that
if burned generates very high temperatures.
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