Quote of the moment: Jonathan Weiner’s Pulitzer-winning explanation of mosquitoes developing immunity to DDT


When evolutionists study these worldwide resistance movements, they see four classes of adaptations arising, because an insect under attack has four possible routes to survival.

Jonathan Weiner, author of The Beak of the Finch

Jonathan Weiner, author of The Beak of the Finch, a story of evolution in our time

First, it can simply dodge. Strains of malarial mosquitoes in Africa used to fly into a hut, sting someone, and then land on the hut wall to digest their meals. In the 1950s and 1960s health workers began spraying hut walls with DDT. Unfortunately in every village there were always a few mosquitoes that would fly in through the window, bite, and fly right back out. Millions of mosquitoes died, but these few survived and multiplied. Within a short time almost all of the mosquitoes in the villages were hit-and-run mosquitoes.

Second, if an insect cannot dodge, it can evolve a way to keep the poison from getting under its cuticle. Some diamondback moths, if they land on a leaf that is tainted with pyrethroids, will fly off and leave their poisoned legs behind, an adaptive trick known as “legdrop.”

Third, if the insect can’t keep the poison out, it may evolve an antidote. A mosquito species called Culex pipiens can now survive massive doses of organophosphate insecticides. The mosquitoes actually digest the poison, using a suite of enzymes known as esterases. The genes that make these esterases are known as alleles B1 and B2. Many strains of Culex pipiens now carry as many as 250 copies of the B1 allele and 60 copies of the B2.

Because these genes are virtually identical, letter by letter, from continent to continent, it seems likely that they came from a single lucky mosquito. The mutant, the founder of this particular resistance movement, is thought to have lived in the 1960s, somewhere in Africa or Asia. The genes first appeared in Californian mosquitoes in 1984, in Italian mosquitoes in 1985, and in French mosquitoes in 1986.

Cover of Jonathan Weiner's book, The Beak of the Finch, a story of evolution in our time

Finally, if the insect can’t evolve an antidote,it can sometimes find an internal dodge. The poison has a target somewhere inside the insect’s body. The insect can shrink this target, or move it, or lose it. Of the four types of adaptations, the four survival strategies, this is the hardest for evolution to bring off — but [entomologist Martin] Taylor thinks this is how Heliothis [virescens, a cotton boll-eating moth] is evolving now.

“It always seems amazing to me that evolutionists pay so little attention to this kind of thing,” says Taylor. “And that cotton growers are having to deal with these pests in the very states whose legislatures are so hostile to the theory of evolution. Because it is evolution itself they are struggling against in their fields each season. These people are trying to ban the teaching of evolution while their own cotton crops are failing because of evolution. How can you be a creationist farmer any more?”

Jonathan Weiner, The Beak of the Finch, a story of evolution in our time, Alfred A. Knopf 1994, pp. 254-255. The book won the Pulitzer Prize for general non-fiction in 1995.

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7 Responses to Quote of the moment: Jonathan Weiner’s Pulitzer-winning explanation of mosquitoes developing immunity to DDT

  1. [...] stuff, but instead weakens the population through reducing diversity.’  Absolutely wrong.  Turns out the new alleles mosquitoes pick up that makes them resistant and immune to DDT, are ALSO the alleles that make mosquitoes resistant to [...]

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  2. [...] that overuse of DDT in agriculture had bred mosquitoes that are resistant and even immune to DDT.  Jonathan Weiner noted in his Pulitzer Prize-winning book, The Beak of the Finch, that today every mosquito on Earth carries at least a few copies of the alleles that allow [...]

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  3. [...] partly because DDT use itself now requires rather extensive testing to make sure it works.  As Jonathan Weiner noted in his Pulitzer Prize-winning The Beak of the Finch, nearly every mosquito on Earth today carries at least one of two alleles which make them resistant [...]

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  4. Chris S. says:

    On a similar note it has been determined that the trait for pesticide resistance (I forget which pesticide – possibly pyrethroids) in aphids is closely linked to the gene for cold tolerance. Ergo if an aphid is resistant to pesticide it is susceptible to extended cold events, something that has helped to ‘keep a lid’ on resistance in the temperate zones so far…

    [More here] (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T5T-41J6698-1V&_user=10&_coverDate=09%2F12%2F2000&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1373298467&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=333618185ebf081804115b69d21ca419)

    Weiner’s book should be a must-read for anyone interested in biology.

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  5. [...] It appears Tren and North make a brand-spanking new junk science claim: That DDT’s value was in repelling mosquitoes. Not so. It does appear to have some repellent character, but it’s not so good as DEET, which is much less toxic, and it’s only a tiny fraction as effective as a bed net, which is dramatically less toxic, longer-lived in effectiveness, and dramatically cheaper than DDT in safe-and-effective use. DDT was valuable because it could knock down mosquito populations for six months or so, while medical professionals could wipe out malaria in humans. But it is impossible to eradicate mosquitoes; the idea was that when mosquito populations roared back, as they always will with DDT, there would be no infected humans from whom the bugs could get malaria to spread. Mosquito resistance and immunity killed that. [...]

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  6. Ed Darrell says:

    You should read the book. Weiner offers up several examples of new species evolving now, and evolved within the past few centuries.

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  7. Jono says:

    “Taylor thinks this is how Heliothis [virescens, a cotton boll-eating moth] is evolving now.”

    So a new species is coming into being! Nar , just adaptions to environment. Hardly random at that! Creationism lives on still.

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