I was skimming through some old Straight Dope articles when I came across the one about the cockroach in the microwave. There was one possibility which immediately came to mind: I have always heard that cockroaches survive nuclear testing. Could it just be that they are such a hardy race as to withstand this sort of torture? If they can withstand a nuclear explosion, I doubt a microwave oven could pose a threat. Any thoughts?
A link to the column is appreciated. I nuked a roach! He didn’t die! Why?
A cockroach cannot, repeat cannot, survive a nuclear blast. However, they probably wouldn’t mind a full-blown nuclear war. The reason for this discrepancy is that even in a full-out war, most of the planet probably wouldn’t be in range of a blast. It’s the fallout that is the wide-area killer, but that takes years to affect an organism, in most cases. Since roaches are so short-lived anyway, this doesn’t really matter.
So this is where the mensa folks hang out. 
Anyway, I too have attempted insect murder by microwave.
In the early 70’s I worked at a Rockwell test facility as a tech, imaging and plotting radar signatures of the B1 bomber.
Being aerospace workers, we had a lot of time on our hands. So, a few friends and I snagged a poor fly, installed it into a waveguide, and cranked up the power. We could see it walking (and flying, I assume) around on the TDR. We left the sucker in there for over six hours.
When we opened up the waveguide, he (the fly) seemed no worse for the wear. I figured “Hey, this fellow deseves his freedom”, but freakin’ Mike smashed our little hero. Mike sucks. 
Peace,
mangeorge
There’s one more reasson that cockroaches and flies don’t die too easily in a microwave oven or waveguide.
The microwave energy is zero at the metal surfaces of the oven. If the oven was an older or cheaper model, it had a metal floor. The better ones have a ceramic or plastic floor that lifts the food up above the zero-microwave floor.
A cockroach or fly is not very tall, so if they stayed on the floor or wall, they’re not going to stick up very far into the microwave-infested space. They’re not exposed to much, maybe 5% as a rough guess. And they’re not too moist, so they’re not going to absorb much. And they’re insects, which unlike us warm-blooded creatures, don’t require a steady temperature.
This is just the sort of research I would expect the straightdope team of researchers to be tackling. I remember having a similar experience with an ant one time. Since no one else seems to be volunteering, I have prepared a plastic jar with airholes for the next neffarious creature that I see skitter under my counter. Unfortunately, this doesn’t happen too often, so don’t expecting any broad base opf experiments with controls and error analysis.
Excellent point about microwave energy being zero at the walls. I forgot about that.
Another thing to keep in mind when making comparisons between nuclear radiation (i.e. from bombs) and microwave ovens.
Microwaves do little more than heat up wet things. If you heat a wet thing up enough, it will make changes to that wet thing and it can stop working right. I.e. a living thing will get cooked and the biological processes can’t proceed. Living thing no more. As has already been mentioned, insects are not very wet (anybody know the approx % of cockroach weight that is water? Is the oft-repeated 98% for humans accurate?) and therefore don’t absorb much microwave energy, especially when close to the metal walls. Plus, cockroaches might be particularly resistant to death by heat. (Anybody volunteer to put one in a conventional oven at 200 degrees F and time its survival?)
As for nuclear energy, assuming that you aren’t including the blast damage, bombs are dangerous because of the radiation they spread around. Nuclear radiation is dangerous because it is ionizing. I.e. when an alpha, beta, or gamma ray passes through a medium, that particle gives up some of its energy to the atoms it encounters, and ionizes many of them. A biologically important molecule that has had one or more of its atoms ionized will usually not work right (at least for a while) and will often break apart and be ruined (for biological purposes). Radiation sickness happens when you are exposed to large amounts of radiation and your organs receive so much ionization damage that the organs themselves don’t work well.
I assume that cockroaches can get radiation sickness if exposed to extremely intense radiation, but it is also quite possible that their organs (such as they are) are very forgiving of damage and can continue to limp along (so to speak) long after our large and complex organs have shut down. Also, just given the small size of cockroaches and their general desire to stay hidden most of the time, their exposure is going to be smaller. And I suspect that they will generally ingest less fallout than humans, partly because of what and where they eat, and partly because of how they breath.
At lower doses of radiation, you aren’t worried about radiation sickness any more, you’re worried about longer-term cancers. Here is where the cockroach’s short lifespan is a huge advantage. A cockroach can hatch, mature, lay eggs, and die of old age in far less time than it takes most cancers to develop. This is going to be true of all insects; I don’t know that the cockroach has any special claim to fame on that count.
What about the long-period cicadas, which live for 17 years? Since it’s possible for an organism younger than that to develop some forms of cancer, it can’t be categorically ruled out. Of course, most of a cicada’s lifespan is spent in a dormant state, but cancer cells are notorious for not following the rules set by their host.
Darn you! Darn you to Heck for finding such an obvious flaw in my Sweeping Generality. But I can still probably rescue my main point…
Anybody know how deep underground cicada larvae burrow for their long slumber? I assume that for Northern climes they at least need to get below the frost line, so call it several inches. This would protect them from a fair amount of external radiation. And external radiation is a relatively minor contributor to cancer deaths, at least to humans.
I think that most of the radiation-induced cancers are caused by ingesting radioactive isotopes that have a long biological half-lives like Strontium-90 (parallels calcium), cesium-137 (parallels potassium), iodine-131 (enters thyroid) and Plutonium-239 (parallels calcium). These isotopes enter the body by being eaten or breathed and stay there, giving your internal organs a nice long radiation bath from the inside.
During a cicada’s dormant state, its ingestion of radioactive fallout would be near zero. Even for active larvae that are eating up a storm before they go dormant, they don’t have bones or thyroid glands, so the above mentioned isotopes might not have as long a biological half-life.
Some of the above info was taken from http://www.larryelectric.com/books/Worldwide_Effects_of_Nuclear_War-Some_Perspectives/RADIOACTIVE_FALLOUT.shtml
I thought it said: “I puked a roach! He didn’t die! Why?”
And I wondered what the heck the questioner was doing eating cockroaches??! And how he thought that would kill one?