If the unthinkable ever happens, it may just be cockroaches and programmers left. From Coffee could provide shield from radiation:
Researchers at India’s Bhabha Atomic Research Centre (BARC) discovered mice injected with caffeine survived high doses of normally lethal radiation.
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Mr George and his team injected 471 mice with caffeine and exposed them to rays of gamma radiation, enough to kill most mice.But 25 days later, 70 per cent of the mice that received 80 milligrams of caffeine per kilogram of body weight were still alive.
In contrast, all 196 mice which had been exposed to the same radiation but had not been given any caffeine died.
The researchers said the caffeine reacts with hydroxyl radicals produced by the radiation.