A week ago, there was a sudden eruption of tiny winged insects in our wooded neighborhood in Linwood.

Whenever you see an unusual swarm of insects, you must investigate to make sure it's not a pest destroying your home.

But last Tuesday, it was termites, which simultaneously emerged and took flight from at least three colonies within a few hundred yards of each other.

Termites are easily distinguished because their dark little bodies seem rather cylindrical to the unaided human eye. Ants have a readily observed "waist" between the thorax and abdomen.

If a termite swarm originates in or immediately adjacent to a dwelling, that almost certainly means the termites are eating the wood of the building, potentially causing very expensive damage.

An estimated $5 billion is spent each year to repair termite damage, and another

$2 billion preventing termite damage.

These termites, fortunately, were not near any buildings. But it was scary to see thousands of them take wing, looking for the right place to start new colonies of 100,000 or more termites.

Few have anything good to say about termites.

Animal rights group PETA, when asked about President Barack Obama's skilled dispatch of a fly intruding on an interview, commented on his lack of Buddha-level compassion for all living things and sent him one of its humane bug catchers.

But even PETA has kept a low profile on the war against termites, except to sympathize with someone who refused to dissect one in school and advise members on how to discourage the pests from targeting a home.

As with so many creatures, the destructive behavior of termites, in its natural setting, is also the insect's great service to the world.

Wood is strong and tough, made primarily of cellulose that is extremely difficult to digest. It allows trees to live long and grow big.

But trees, too, must die, and without the world's 2,100 species of termites - 41 in North America - to eat all that fallen wood, land would be a lot less hospitable to large, mobile animals.

Even the trees themselves would suffer, since the breakdown of their remains would take a lot longer, impoverishing the soil that nourishes the new, growing trees.

And termites are social insects, interesting animals with castes and divisions of labor that at first glance seem beyond the capabilities of their tiny mental capacity.

And unlike ants and bees, termites are not gender-biased.

Males and females are part of each caste: reproductives, substitute reproductives, workers and soldiers.

In some parts of the world, they construct mound homes several feet tall. Here, they live underground and we only see them when they swarm or destroy our wooden structures.

But just because you don't see them, don't assume they are not there. If there are trees, it's safe to assume there are termites.

Nature wouldn't have it any other way.

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