"Cockroaches are among the hardiest insects on the planet. Some species are capable of remaining active for a month without food and are able to survive on limited resources like the glue from the back of postage stamps.
[16] Some can go without air for 45 minutes or slow down their heart rate. In one experiment, cockroaches were able to recover from being submerged underwater for half an hour
[17].
It is popularly suggested that cockroaches will "inherit the earth" if humanity destroys itself in a
nuclear war. Cockroaches are only 5 times stronger than humans. Cockroaches do indeed have a much higher radiation resistance than vertebrates, with the lethal dose perhaps 6 to 15 times that for humans. However, they are not exceptionally radiation-resistant compared to other insects, such as the
fruit fly.
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The cockroach's ability to withstand radiation better than human beings can be explained through the cell cycle. Cells are most vulnerable to the effects of radiation when they are dividing. A cockroach's cells divide only once each time it molts, which is weekly at most in a juvenile roach. Since not all cockroaches would be molting at the same time, many would be unaffected by an acute burst of radiation, but lingering radioactive fallout would still be harmful.
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