Rats live wherever people live, with one exception: the Canadian province of Alberta. A rat sighting in Alberta is a major local event that mobilizes the local government to identify and eliminate any hint of infestation. Rat sightings makes the local news. Alberta prides itself on being the sole rat-free territory in the world, but in order to achieve this feat, it had to go to war with the rat. On this episode of Decoder Ring we recount the story of how Alberta won this war, through accidents of history and geography, advances in poison technology, interventionist government policy, mass education programs, rat patrols, killing zones and more. The explanation tells us a lot about rats and a lot about humans, two species that are more alike than we like to think.   If you love the show and want to support us, consider joining Slate Plus. With Slate Plus you can get ad free podcasts, bonus episodes, and much more. Learn more about your ad choices. Visit megaphone.fm/adchoices