Now, with a post title like that I'd entirely forgive you for thinking I was making some kind of a joke. But the story I'm about to relate is true: Here is a link to the original story from the award winning RIA Novosti newspaper.
Super 'roaches arrive from space:
In 2008 the Russian space agency launched an unmanned spaceship called 'Foton-M':
Above: A Soyuz rocket launches with a Foton-M spaceship as it's payload to orbit.
It was unmanned, but it wasn't uncrewed: The capsule contained a host of terrestrial life forms, including two cockroaches.
The ship had no specific destination, it just went into orbit, circled the Earth for a few weeks, and then came home. The point was to test the effects of the space environment on these animals. This was partly to help protect future cosmonaut launches from unwanted effects, and partly just for s**ts and giggles... uh, I mean scientific curiosity.
When the capsule returned to Earth the researchers discovered that the roaches had got it on in space, and one was pregnant.
I'll let you mind dwell on that lovely mental image for a moment......
This was actually pretty exciting for the researchers: The effects of microgravity on reproduction are still poorly understood.
But, when the children of the 'roach-o-nauts arrived, the researchers got a B-movie style shock: The cockroaches conceived in space grew at a colossal rate, quickly becoming three times as big as normal roaches of the same age. They moved remarkably fast, were more aggressive, and were even tougher than normal roaches. Given that Earth roaches can survive massive doses of radiation, resist extreme heat and cold, go for hours with out oxygen, and even survive decapitation, it's easy to see that the researchers might have gone home a bit worried.
Especially when they asked each other the question : "What will happen if these b*****ds get out of the lab?"
As it turned out there were to be no trillion strong swarms of indestructible space 'roaches sweeping across Russia: The children of the space roaches were perfectly normal - like Superman loosing his powers on his native planet Krypton, super-cockroach's kids loose their powers when conceived on Earth.
Exactly what it was on that space flight that caused the cockroaches to develop differently has never been identified. But 'roaches aren't the only scary organism to have been made scarier by exposure to space: Salmonella (a leading cause of infant mortality worldwide), for example, is much more virulent in space - and working out why actually led to a better vaccine for the terrestrial variety.