Engines of Our Ingenuity

No. 441:
THE INSECT EMPIRE

by John H. Lienhard

Click here for audio of Episode 441.

Today, we look for emissaries to send to the insect empire. 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.

Entomologists, the people who study insects, tell about a professor who once said that DDT would put an end to their field. When entomologists met in Washington for their hundredth anniversary in 1989, they showed us the grim outcome of that 40-year-old story. Dr. Thomas Eisner, from Harvard, remarked,

Bugs aren't going to inherit the earth. They already own it. It's time to make peace with the Landlord.
To make their point, insect scientists give us biomass figures. The social insects alone -- ants, bees, and the like -- outweigh vertebrates 7 to 1. Don't forget, that means weighing termites and wasps against people and whales. That's a lotta bugs! We've identified 750,000 species so far, but ten million insect species are still unclassified. We can identify only one bug out of 13.

So, what about DDT? Forty years ago, bugs ate seven percent of our crops. Now they're eating 13 percent. Does that make sense? It does when you consider two facts. One is that insects quickly adapt to chemicals. We've created whole new taxonomies of DDT-proof bugs. Our farmers also grow far more hybrids today. And hybrids don't have the same Darwinian talent for survival. They need more protection from bugs, and we can't provide it.

Disease-carrying bugs are also on the rise. Malaria mosquitoes have found their way around insecticides. Malaria deaths are back up to a million a year. River blindness hits 40 million Africans annually. Elephantiasis affects 400 million people.

So what's to be done? Experts tell us we should quit trying to exterminate Earth's largest species. The time has come to start forging a peace with them. We don't need soldiers. We need diplomats. We need far more entomologists to help us coexist with the insects. And entomologists are becoming rare.

Our schools graduated 170 PhDs a year in the 1970s -- not a whole lot. Now that's down to 130 a year. So the fellow who predicted DDT would do away with entomologists was close to right after all. The problem is, DDT left the insects themselves stronger than ever.

Like any good crisis, this one hides opportunity. Insects offer vast untapped possibilities. They secrete every kind of potential healing drug, repellent, fungicide, and even foodstuff. Honey is only one. The bugs are ready to show us how to survive among them.

So if you're still young, and you're looking for a field, give it a thought. Insects are coinheritors of the Earth. It could be fun getting to know them.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)


Holden, C., Entomologists Wane as Insects Wax. Science, Vol. 246, 10 Nov., 1989, pp. 754-756.


The Engines of Our Ingenuity is Copyright © 1988-1997 by John H. Lienhard.

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