RENEE MONTAGNE, host:
Food scares and bugs can disrupt a good picnic. This is the time of year when many of us find ourselves spending time - and not because we want to - with certain very irritating buzzy little critters - mosquitoes. Nobody likes mosquitoes. Nobody except perhaps other mosquitoes, and well, one guy that talked to our science correspondent Robert Krulwich.
(Soundbite of buzzing)
ROBERT KRULWICH: Yes, they are irritating. Very, very irritating. There's so many of them, carrying god knows what diseases.
Mr. DAVID QUAMMEN (Science Writer): Well, there's a whole list of diseases they transmit. They can transmit malaria, yellow fever, dengue, encephalitis, filariasis.
KRULWICH: And so I asked David Quammen, a well-know science writer who's well aware of the suffering the mosquitoes can cause, is there anything nice that we can say about mosquitoes? Anything at all? And David, who's a very kind guy...
Mr. QUAMMEN: I was sitting in the backyard this morning and a mosquito came flying by, and I found that I didn't have the heart to swat her. I shooed her away and she came back about four times. I just didn't have it in me to squash her.
KRULWICH: Because as it happens, in an essay he wrote more than 20 years ago, David Proposed three nice things to say about mosquitoes, things is did not know. Like...
Mr. QUAMMEN: Fifty percent of all mosquitoes that are flying around are completely harmless.
KRULWICH: Because 50 percent of all mosquitoes are guys. And says David...
Mr. QUAMMEN: My understanding is that the guys don't bite.
KRULWICH: So every time you go...
(Soundbite of slapping)
KRULWICH: ...you're slapping the lady?
Mr. QUAMMEN: Almost certainly, because the male mosquito has no reason whatsoever to land on you.
KRULWICH: Well then, but who do the male mosquitoes land on? Is it flowers?
Mr. QUAMMEN: No, they're doing - the guys are doing what guys do. They're looking for females.
Mr. QUAMMEN: They're looking for sex. And the females - yes, they want sex but they also want blood.
KRULWICH: And they want blood because mosquitoes are wonderful mommies. They need protein to feed their babies. And how many babies do they feed?
Mr. QUAMMEN: Oh, let's see. I think 200 - roughly 200 in a clutch. And in the course of a reasonable summer, I think that they can produce about 10 clutches - about 2,000.
KRULWICH: Two thousand babies. So that means you have to have a lot of protein if you're going to build 2,000 babies, don't you think?
Mr. QUAMMEN: Yeah.
KRULWICH: Which is why lady mosquitoes are so good at finding warm mammals to feed on. How they do it nobody's sure, but one guess is they can sense body heat. Which bring us to an Old Italian folktale.
Mr. QUAMMEN: That if you slept with a pig in the bedroom, it would offer you some protection against mosquitoes. And the reason for that, I think, was that the pig was operating at a higher body temperature, say 101 or 102 degrees Fahrenheit instead of 98.6.
KRULWICH: So the mosquito then zips right by you and heads right for the pig.
Mr. QUAMMEN: Yes. That apparently was the concept.
(Soundbite of laughter)
Mr. QUAMMEN: Now we have mosquito nets and screened windows.
KRULWICH: The point is, they're so good at finding warm bodies, they've been biting us for hundreds of thousands of years, which leads to perhaps their single greatest achievement, says David.
Mr. QUAMMEN: So when we emerged as a species and then started moving around, we plowed the fields and cut down the trees and created cities and agricultural landscapes.
KRULWICH: But the hot, wet equatorial rain forests that are still hosts to more species and more variety of life than any other places on Earth. Humans mostly avoided those places because if you entered a rain forest, chances are you'd get bit and then you'd get sick.
Mr. QUAMMEN: By way of malaria and dengue and yellow fever and some of these other disease that I've mentioned.
KRULWICH: So while most habitats have been invaded by humans, when it comes to tropical rain forests...
Mr. QUAMMEN: We didn't do that. Why didn't we? Well, one of the reasons, I'm convinced, is that mosquitoes were there standing guard, making those places difficult...
KRULWICH: Safe for all the butterflies and the bugs and the lovely leaves. I can hear the music now building in the background.
(Soundbite of music)
Mr. QUAMMEN: There it is. I can hear it too.
Unidentified Man: Hail the lady mosquito, fiercely protecting beetles and orchids, ferns, butterflies, biting mankind to save the last true wildernesses on Earth. Nature's hero, the lady mosquito, we thank you.
KRULWICH: So one: the boys don't bite. Two: the ladies make great mommies, great providers. And three: mosquitoes defend the Earth's rain forest. That's your essential argument.
Mr. QUAMMEN: That's my essential argument. That's my story and I'm sticking to it.
(Soundbite of laughter)
KRULWICH: I'm Robert Krulwich, NPR News.
MONTAGNE: Well, of course you'll have to provide the music, but David Quammen's original essay on mosquitoes appeared in his collection "Natural Acts."
(Soundbite of music)
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