Who would have ever thought that the Teenage Mutant Ninja Turtles would have such staying power? I remember when they launched back when I was in about third or fourth grade. They'd probably been around since long before that even, but I just didn't know about them. Perhaps their brand of mutantry even preceded nuclear mutation? If that's the case, then they'd be mutants of some kind of natural selection, but that seems unlikely. Even more unlikely than a franchise based on teenage mutant ninja turtles thriving for 25 years.