By JAMES GORMAN
Published: June 22, 2004
The New York Times
Elizabeth Willott is the kind of professor who gives the ivory tower a good name.
She is an entomologist and environmental ethicist at the University of Arizona, and I called her to ask a simple question: What good are mosquitoes?
Dr. Willott seemed like a good person to call because she has spent some time thinking about these issues. She has an article in the current issue of Restoration Ecology titled "Restoring Nature, Without Mosquitoes?"
In it she notes that in planning wetland restoration, people sometimes fail to give enough thought to one inevitable consequence - more mosquitoes. In the bad old days, not all wetlands were drained to build hotels. Another motivation was the real fear of death and disease, as spread by mosquitoes.
So, I asked, what about mosquitoes? Would everything really collapse if we got rid of them? Well, she said, no. The web of life is not that fragile. "If you take a snip, it won't unravel."
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In fact, she said, there is "quite a bit of ecological research now showing that removal of a species doesn't make a huge difference." If the species of mosquitoes that are intimately connected with human beings were made to disappear, there might be some ecological disturbance, but "you probably could remove them without catastrophe."
Do they do anything of value, then? That depends on your point of view, she said. The philosophical arguments about intrinsic value versus instrumental value can get quite complicated. In essence they ask whether a mosquito, or a tree, or anything, has a value in and of itself, apart from what human beings think.
This is the sort of discussion that may be intriguing in an air-conditioned classroom, but seems absolutely incomprehensible at dusk near a marsh. If there's a chance that our children might get encephalitis, then we're ready to wipe mosquitoes off the face of the earth.
One small step beyond this "me, me, me" approach is to think about the value of any given organism to environmental balance. This is still not intrinsic value, since environmental balance is useful to people, but it is a bit less self-centered. Step outside the anthropocentric view of life and one possible value of mosquitoes is population control. Mosquitoes have historically kept human populations down worldwide, and still do in much of the third world. The problem is that they do this by facilitating pestilence and death, so this is not going to enhance their status, among human beings at least.
Mosquitoes may also keep some other animal populations down by spreading disease - something we might be able to see the value of. And other creatures - some fish, frogs birds and bats - eat them. It's possible that if we were able to wipe out mosquitoes, some other species might either suffer from lack of food, or explode in numbers because the burden of disease was lifted.
Another value of mosquitoes, perverse to some, obvious to others, is that they "keep out the riffraff," meaning human beings. Concentrations of pests offer protection to wilderness areas. The tsetse fly, which causes livestock disease as well as human sleeping sickness, has kept humans away from some wildlife refuges and has been called "Africa's best conservationist." Of course, this view has been described by others as ecological imperialism.
In any case, the reality, said Dr. Willott, is that "we're not going to get rid of the mosquitoes." It's just impossible, particularly if we want to use methods that don't kill off everything else. DDT is very effective at mosquito control, but it can be disastrous for birds of prey.
When I asked Dr. Willott if she thought it was immoral to try to make a species go extinct, assuming you could do it without hurting other organisms, she thought the question was significant enough to require a formal statement. "Striving for the unachievable is not an appropriate use of resources," she said. "If one acknowledges that eradication is highly unlikely to work or might have serious side effects, the moral thing to do would be to find another way." In other words, don't be stupid.
What she suggests is that we take the middle ground and try to kill some of the mosquitoes some of the time.
I mentioned to her at the end of our conversation that although mosquitoes were not that much fun to be around in reality, I shared her fascination with them. As a subject to talk and write about, they are irresistible.
Yes, she said, "and they find us the same."
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