Today, we learn a hard lesson about compensation in
nature. The University of Houston's College of
Engineering presents this series about the machines
that make our civilization run, and the people
whose ingenuity created them.
It was 1982. I was looking
at an empty house with house-hunting friends,
moving into town. We stood in the yard to look at
the roof. Suddenly pain bathed my lower leg. I
looked down. It was crawling with ants. By the time
I'd run into the house and stripped off my shoes,
socks, and pants, they'd stung me in 40 places. I
was out for the day. My leg took weeks to heal.
That was my first meeting with an insect called
Invicta, -- Latin for invincible. He's better known
as the fire ant. First he bites into you to form a
grip. The bite's harmless; but then he stings you.
He injects a mixture of venom and bacteria. It
leaves a nasty, painful, and slow-healing little
wound.
We've spent millions for a chemical assault on fire
ants. The chemicals have done more to clear out the
fire ant's natural insect enemies. They've killed
birds. They've left carcinogens in human tissue.
And the fire ants have prospered.
The ants that stung me came out of a single queen
mound. Unpleasant as that was, it was only a bother
-- not a real threat to my life. Meanwhile, the
species has mutated under attack. Now Invicta has
learned to create mounds with many queens.
The mutant creates vast burrows with millions of
workers. The females are the gatherers and they're
omnivorous. They go after other insects, crops,
even highway expansion joints. Veterinarians at
Texas A & M have treated dozens of young deer
for fire ant bites. Electric fields draw the ants.
They've knocked out relays, traffic lights -- even
airplane altimeters.
Entomologists are working on two lines of battle.
One is chemical. They've given up on insecticides.
Now they look for chemicals that miscue the mating
process or sterilize the queens.
The other attack is not chemical at all. It's
sociological. We're looking around for the fire
ant's natural enemies. Invicta mounds in Brazil
offer clues. Many are shared by other insects.
Maybe some of those bugs keep Invicta in check.
One insect is a sure enemy of the new fire ants.
His identity is the crowning irony in the whole
business. It turns out that the old single-queen
colonies are vicious enemies of the multiple-queen
mounds. In the end, we might find ourselves using
the old ants to fight the new ones.
If it's any consolation, the old single-queen fire
ant isn't entirely bad to have around. He's a tough
natural enemy of other pests -- like corn worms and
boll weevils. And he'll really control the flea
population in your back yard.
I'm John Lienhard at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
