Operation Cat Drop: history or hoax?

Many accounts of Operation Cat Drop were accompanied by comics, so it’s only fitting, I guess that this one should as well.  (Sketch by HT)

Originally posted on The Sieve.

Once upon a time in Borneo, everybody was dying of malaria, so they sprayed a lot of the insecticide DDT (dichlorodiphenyltrichloroethane), which killed the mosquitoes that transmitted the disease. Cases dropped, but inexplicably, peoples’ roofs started caving in. DDT had also killed wasps that kept the caterpillar population in check, so the caterpillars ate the roof thatch. Geckos ate the wasps, and cats ate the geckos. Cats started dropping dead, and the rat population flourished, which lead to an outbreak of the plague. So, to solve the problem, health officials parachuted cats into Borneo.

Or, at least that’s how the story goes.

I first heard of this ecological fable — nicknamed “Operation Cat Drop” — from a friend who liked to break it out at dinner parties. Frankly, it sounded a bit ridiculous. So, ridiculous in fact, that somebody could very well have made it up, and some have argued that the tale is just that: fiction. The cat story started popping up in print in the 1960s, making appearances in The New York TimesTime, and Natural History magazine. In the late 1960s and early 70s, biomagnification and the ecological impacts on avian species took center stage in the public debate over the safety of DDT. But, I’ve always wondered whether there was any truth to the cat story, which did come up in congressional hearings on DDT use. Turns out, there’s more than you’d think. Patrick O’Shaughnessy, an environmental engineer at the University of Iowa, did some digging and found kernels of truth from which the cat drop myth probably grew. His work was published in the American Journal of Public Health. Here’s what we know…

In the 1950s, the World Health Organization (WHO) launched a global effort to eradicate malaria, following successful campaigns in the United States, Europe, and Venezuela. Resistance to the insecticide had popped up in some mosquitoes, but they were very optimistic. Perhaps a little too optimistic. From 1952-55, in the Sarawak region of Borneo, malaria control teams sprayed DDT, benzene hexachloride, and briefly dieldrin twice a year inside local long houses with thatch roofs. At first, the program enjoyed some success. From 1953 to 1955, the fraction of local mosquitoes carrying the disease fell from 35.6% to 1.6%.

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The Salt’s Top Posts Of 2012

Credit: Stephan Kuhn/Creative Commons
Credit: Stephan Kuhn/Creative Commons

One of my stories made the 2012 top ten list for NPR’s fabulous food blog, The Salt.

The piece actually ran last Friday, so it’s fairly recent. It’s about the debate over how humans evolved lactose tolerance — quite the mystery in the scientific community. Basically, 10,000 years ago most babies could drink milk because they had the gene for lactase, but the gene turned off in adults. Milk and dairying came with ancient agriculture, and several mutations for lactose tolerance became more frequent — people were passing them down to children. But if milk gave them diarrhea, then what made them drink it, and what gave milk drinkers a survival advantage? Turns out the answer is a bit of a can of worms. For more on that, here’s the original story. It ranked #3 on the list, so not too shabby.

And now…*celebratory dancing*!

Oh the things a curious Dane can do with a used CT scanner…

Recently, there’s been a lot of ho-ing and hum-ing about recreating stradevarious violins and discovering the medical secrets of mummies from of all things CT scans. But, WaPo finally gives us a look at one of the guys behind the curtain: the Smithsonian’s Bruno Frolich.

“Oh, the things Bruno Frohlich can scan. Ancient whale skulls. Smashed human ones. Stradivarius violins. Violas. Cellos. Guitars. Stringed instruments from Mongolia. Apollo spacesuits. Eagle feathers. Mummified birds from Egypt oddly missing their heads. Dinosaur leg bones, fossilized. Thigh bones, hip bones, arms bones, teeth. An infant’s iron casket dug up in the District. Live turtles. Dead crocodiles. Mummy after mummy from Egypt. And one from Peru. The Smithsonian Institution owns 137 million things. Over the past 15 years, Frohlich, it seems, has scanned them all. Okay, not quite. But if he had enough time, he would. ‘This is my hobby,’ Frohlich says of his job.”

What a cool dude. Click to read the excellent article by Brian Vastag.